Internet-Of-Things (Iot) - Based Smart Agriculture: Toward Making The Fields Talk
Internet-Of-Things (Iot) - Based Smart Agriculture: Toward Making The Fields Talk
0:
RESEARCH CHALLENGES AND OPPORTUNITIES
Received July 7, 2019, accepted July 19, 2019, date of publication August 1, 2019, date of current version September 23, 2019.
Digital Object Identifier 10.1109/ACCESS.2019.2932609
  ABSTRACT Despite the perception people may have regarding the agricultural process, the reality is that
  today’s agriculture industry is data-centered, precise, and smarter than ever. The rapid emergence of the
  Internet-of-Things (IoT) based technologies redesigned almost every industry including ‘‘smart agriculture’’
  which moved the industry from statistical to quantitative approaches. Such revolutionary changes are
  shaking the existing agriculture methods and creating new opportunities along a range of challenges.
  This article highlights the potential of wireless sensors and IoT in agriculture, as well as the challenges
  expected to be faced when integrating this technology with the traditional farming practices. IoT devices
  and communication techniques associated with wireless sensors encountered in agriculture applications are
  analyzed in detail. What sensors are available for specific agriculture application, like soil preparation, crop
  status, irrigation, insect and pest detection are listed. How this technology helping the growers throughout
  the crop stages, from sowing until harvesting, packing and transportation is explained. Furthermore, the use
  of unmanned aerial vehicles for crop surveillance and other favorable applications such as optimizing crop
  yield is considered in this article. State-of-the-art IoT-based architectures and platforms used in agriculture
  are also highlighted wherever suitable. Finally, based on this thorough review, we identify current and future
  trends of IoT in agriculture and highlight potential research challenges.
  INDEX TERMS Food quality and quantity, Internet-of-Things (IoTs), smart agriculture, advanced agricul-
  ture practices, urban farming, agriculture robots, automation, future food expectation.
VOLUME 7, 2019       This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see http://creativecommons.org/licenses/by/4.0/   129551
                                                                       M. Ayaz et al.: IoT-Based Smart Agriculture: Toward Making the Fields Talk
are playing important roles in the economies of many nations.       constantly with higher accuracy and are able to, most impor-
Furthermore, the food-crops-based bioenergy market started          tantly, detect early stages of unwanted state. This is the reason
to increase recently. Even before a decade, only the produc-        why modern agriculture involves the usage of smart tools
tion of ethanol utilized 110 million tons of coarse grains          and kits, from sowing to crop harvesting and even during
(approximately 10% of the world production) [7], [8]. Due           storage and transportation. Timely reporting using a range of
to the rising utilization of food crops for bio-fuel production,    sensors makes the entire operation not only smart but also cost
bio-energy, and other industrial usages, food security is at        effective due to its precise monitoring capabilities. Variety of
stake. These demands are resulting in a further increase of         autonomous tractors, harvesters, robotic weeders, drones, and
the pressure on already scarce agricultural resources.              satellites currently complement agriculture equipment. Sen-
   Unfortunately, only a limited portion of the earth’s surface     sors can be installed and start collecting data in a short time,
is suitable for agriculture uses due to various limitations, like   which is then available online for further analyses nearly
temperature, climate, topography, and soil quality, and even        immediately. Sensor technology offers crop and site-specific
most of the suitable areas are not homogenous. When zoom-           agriculture, as it supports precise data collection of every site.
ing the versatilities of landscapes and plant types, many new          Recently, the Internet-of-Things (IoT) is beginning to
differences start to emerge that can be difficult to quantify.      impact a wide array of sectors and industries, ranging
Moreover, the available agricultural land is further shaped by      from manufacturing, health, communications, and energy
political and economic factors, like land and climate patterns      to the agriculture industry, in order to reduce inefficiencies
and population density, while rapid urbanization is constantly      and improve the performance across all markets [12]–[16].
posing threats to the availability of arable land. Over the past    If looking closely, one feels that the current applications are
decades, the total agriculture land utilized for food production    only scratching the surface and that the real impact of IoT and
has experienced a decline [9]. In 1991, the total arable area       its uses are not yet witnessed. Still, considering this progress,
for food production was 19.5 million square miles (39.47% of        especially in the near past, we can predict that IoT technolo-
the world’s land area), which was reduced to approximately          gies are going to play a key role in various applications of the
18.6 million square miles (37.73% of the world’s land area)         agriculture sector. This is because of the capabilities offered
in 2013 [10]. As such, the gap between demand and supply            by IoT, including the basic communication infrastructure
of food is becoming more significant and alarming with the          (used to connect the smart objects—from sensors, vehicles,
passage of time.                                                    to user mobile devices—using the Internet) and range of
   Further examination showed that every crop field has dif-        services, such as local or remote data acquisition, cloud-
ferent characteristics that can be measured separately in terms     based intelligent information analysis and decision making,
of both quality and quantity. Critical characteristics, like soil   user interfacing, and agriculture operation automation. Such
type, nutrient presence, flow of irrigation, pest resistance,       capabilities can revolutionize the agriculture industry which
etc., define its suitability and capability for a specific crop.    probably one of most inefficient sectors of our economic
In most of situations, the differentiations of characteristics      value chain today. To summarize this discussion, figure 1 pro-
can exist within a single crop field, even if the same crop is      vides the main drivers of technology, while figure 2 highlights
being cultivated in entire farm; hence, site-specific analyses
are required for optimal yield production. Further, adding the
dimension of time, specific crops in the same field rotate
season-to-season and biologically reach different stages of
their cycle within a year in areas where locational and tempo-
ral differences result in specific growth requirements to opti-
mize the crop production. To respond to these demands with a
range of issues, farmers need new technology-based methods
to produce more from less land and with fewer hands.
   Considering the standard farming procedures, farmers
need to visit the agriculture sites frequently throughout the
crop life to have a better idea about the crop conditions.
For this, the need of smart agriculture arises, as 70% of
farming time is spent monitoring and understanding the crop
states instead of doing actual field work [11]. Considering
the vastness of the agriculture industry, it incredibly demands
for technological and precise solutions with the aim of sus-
tainability while leaving minimum environmental impact.
Recent sensing and communication technologies provide a
true remote ‘‘eye in the field’’ ability in which farmers can
observe happenings in the field without being in the field.
Wireless sensors are facilitating the monitoring of crops           FIGURE 1. Key drivers of technology in agriculture industry.
to 75% e.g. Brazil, further in some underdeveloped countries,                movement [38]. Any sort of nutrients deficiency or apply-
even it exceeds 80% [34]. The main reason for this high water                ing them improperly can be seriously harmful for the plant
consumption is the monitoring procedure as even in 2013,                     health. More importantly, excessive use of fertilizer not only
crops visual inspection for irrigation decision-making was                   results in financial losses but also creates harmful impacts
very common, as nearly 80% of farms in United States were                    to the soil and environment by depleting the soil quality,
observed by this [10], [35]. According to the UN Convention                  poisoning ground water, and contributing to global climate
to Combat Desertification (UNCCD) estimates in 2013 show                     changes. Overall, crops absorb less than half the nitrogen
that there were 168 countries affected by desertification and                applied as fertilizer, while remaining either emitted to the
by 2030, almost half of the world population will be living                  atmosphere or lost as run off. Unbalanced use of fertilizer
in areas with high water shortages [36]. Considering the fig-                leads to an imbalance in both soil nutrient levels and global
ures of water crises around the globe, same time its increasing              climate as, reportedly, around 80% of the world’s deforesta-
demands in agriculture and many other industries, it should be               tion has occurred due to agricultural practices alone [39].
provided to places only where it is needed, most importantly,                   Fertilization under smart agriculture helps to precisely
in required quantities. For this purpose, increased aware-                   estimate the required dose of nutrients, ultimately minimize
ness has been implemented to conserve the existing under-                    their negative effects on the environment. Fertilization
stress water resources by employing more efficient irrigation                requires site-specific soil nutrient level measurements based
systems.                                                                     on various factors, such as crop type, soil type, soil absorption
   Various controlled irrigation methods, like drip irrigation               capability, product yield, fertility type and utilization rate,
and sprinkler irrigation, are being promoted to tackle the                   weather condition, etc. The reason is that the measurement
water wastage issues, which were also found in traditional                   of soil nutrient level is not only expensive but also time
methods like flood irrigation and furrow irrigation. Both the                consuming, as, typically, investigations of soil samples at
crop quality and quantity are badly affected when facing                     each location are required. To better depict this discussion,
water shortage, as irregular irrigation, even excess, leads to               figure 4, summarizes the major inputs, processes and resul-
reduced soil nutrients and provokes different microbial infec-               tant outputs of smart agriculture.
tions. It is not a simple task to accurately estimate the water                 New IoT-based fertilizing approaches help to estimate
demand of crops, where factors like crop type, irrigation                    the spatial patterns of nutrients requirements with a higher
method, soil type, precipitation, crop needs, and soil moisture              accuracy and minimum labor requirements [40], [41].
retention are involved. Considering this fact, a precise soil                For example, the Normalized Difference Vegetation Index
and air moisture control system using the wireless sensors not               (NDVI) uses aerial/satellite images to monitor crop nutrient
only makes an optimal use of water but also leads to better                  status [42], [43]. Basically, NDVI is based on the reflection
crop health.                                                                 of visible and near-infrared light from vegetation and is used
   The current situation of irrigation methods is expected                   to estimate the crop health, vegetation vigor, and density,
to be changed by adopting the emerging IoT technologies.                     further contributing to assess the soil nutrient level. Such
A significant increase in crop efficiency is expected with                   precise implementation can significantly improve the fertil-
the use of IoT based techniques, such as crop water stress                   izer efficiency, simultaneously reducing the side effects to the
index (CWSI)-based irrigation management [10], [35]. For                     environment. Many recent enabling technologies, like GPS
this, attaining crop canopy at different periods and air tem-                accuracy [44], geo mapping [45], Variable Rate Technology
perature are needed for the calculation of CWSI. A wireless                  (VRT) [46], [47], and autonomous vehicles [48], are strongly
sensors based monitoring system where all the field sensors                  contributing to IoT-based smart fertilization.
are connected to collect the mentioned measurements, further                    Other than precision fertilization, fertigation [49] and
transmit to processing center where corresponding intelli-                   chemigation [50], [51] are other benefits of IoT. In these
gent software applications are used to analyze the farm data.                methods, water-soluble matters, such as fertilizers, soil
Not only this but information from other sources including                   amendments, and pesticides, can be applied through the
weather data and satellite imaging is applied to CWSI models                 irrigation system. Although, these methods are not new to
for water need assessment, and finally specific irrigation                   agriculture and have been applied over last three decades,
index value is produced for each site. A prominent example is                their precise use with real results has been witnessed only
VRI (Variable Rate Irrigation) optimization by CropMetrics                   with IoT integration [52], [53]. Based on recent outcomes,
[37], which works according to topography or soil variability,               fertigation is considered as the best management practice to
ultimately improves the water use efficiency.                                improve the effectiveness of many agriculture matters; most
                                                                             importantly, it can be integrated with IoT-based smart farming
C. FERTILIZER                                                                infrastructure seamlessly.
A fertilizer is a natural or chemical substance that can
provide important nutrients for the growth and fertility of                  D. CROP DISEASE AND PEST MANAGEMENT
plants. Plants mainly need three key macronutrients: nitrogen                The Great Famine, also known as the Irish Potato Famine,
(N) for leaf growth; phosphorus (P) for root, flowers, and                   in which approximately one million Irish people died
fruit development; potassium (K) for stem growth and water                   around 1950, resulted due to crop failure and yield
not only helps to maximize the crop quality and production                   and pesticides. Soon it was realized that these conven-
but also provides an opportunity to adjust the management                    tional ways were not adequate enough to fit this demand
strategy. Although, harvesting is the last stage of this process,            gap; hence, agriculture scientists have begun thinking of
proper scheduling can make a clear difference. To obtain the                 other alternatives, like bioengineered (BE) foods. BE foods,
real benefits from crops, farmers need to know when these                    also known as genetically modified (GM) or genetically
crops are actually ready to harvest. Figure 5 represents a                   engineered (GE) foods, are foods produced by introduc-
snapshot of a farm area network (FAN) that can portrait the                  ing changes into their DNA using the methods of genetic
whole farm to the farmer in real time.                                       engineering. However, several studies highlight their serious
                                                                             effects on human health, including infertility, disruption in
                                                                             immune system, accelerated aging, faulty insulin regulations,
                                                                             etc. [75], [76]. All these and many other similar technologies
                                                                             did not receive much popularity and acceptance in society
                                                                             because people prefer bio and organic food. In this regards,
                                                                             massive research has been conducted for decades in which
                                                                             sensors and IoT-based technologies are helping to improve
                                                                             conventional agriculture processes to enhance yield produc-
                                                                             tion without, or with minimum, effect on its originality.
                                                                             For this purpose, new sophisticated and more controlled
                                                                             environments are projected to tackle the above-mentioned
                                                                             issues. The importance and involvement of new technologies
                                                                             is more critical, as we are moving toward more cultured and
                                                                             urban farming. In fact, it would not be incorrect for one to
                                                                             say that the success of these advanced practices is in doubt
                                                                             without using sensor-based technologies.
B. VERTICAL FARMING                                                 When combining hydroponics with VF, a farm of 100 sq.
The world needs more farmable lands to fulfill increased            meters can produce the crop equivalent to 1 acre of traditional
food demands, but reality is that one-third arable land was         farm, most importantly upto 95% less water and fertilizers
lost during the last four decades due to erosion and pollution      utilization and without pesticides/herbicides [87]. Currently,
[80], [81]. Unfortunately, current agricultural practices based     available systems and sensors e.g. [88], [89] are not only
on industrial farming are damaging the soil quality far faster      used to monitor a range of parameters and take readings at
than nature can rebuild it. Overall, it is estimated that erosion   predefined intervals but, also, the measurements are stored so
rates from cultivated fields is 10 to 40 times greater than the     that can be used to analyze and diagnostic purpose later on.
soil formation rates [82]. Considering the reduction of arable         Under this application, the precision of nutrient measure-
land issues, it could be a disaster for food production in the      ments is crucial, as such, a highly reliable wireless control
near future with current agriculture practices. Further, as we      system for tomato hydroponics is proposed in [90] in which
mentioned, 70% of fresh water is only used for agriculture          they focused on various communication standards that are
purpose, which can increase the burden on existing limited          least effected by plants’ presence and their growth. The
water reservoirs. Vertical Farming (VF) is an answer to meet        monitoring of solution contents and their precision is most
the challenges of land and water shortages.                         critical under this method; for this purpose, many systems
   VF in the form of urban agriculture offers an opportunity        are offered to check the presence of contents considering the
to stack the plants in a more controlled environment result-        plant demands. In [91] a wireless-sensor-based prototype is
ing in, most importantly, significant reduction in resource         proposed to deliver a turn-key solution for the hydroponic
consumption. By following this method, we can increase the          cultivation which offers real-time measurements for soilless
production multiple times, as only a fraction of ground sur-        indoor growing. Further, a compact sensor module is pre-
face is required (depending on the number of stacks) as com-        sented in [92], which uses oscillator circuits to measure the
pared to traditional agriculture practices. Not only for ground     presence and concentrations of various nutrients and water
surface, this system is highly efficient in terms of other          levels.
resources, as well. For example, according to Mirai, a Japan
based indoor farm developer presented the figures regarding         D. PHENOTYPING
a Japanese farm comprised of 25,000 square meters. The fig-         The previously discussed smart methods look more promis-
ures are highly encouraging, as it is producing 10,000 heads        ing for the future of agriculture, as they are already being
of lettuce per day (double the production when compared             used to produce different crop products under precise envi-
with traditional methods) and is, most importantly, consum-         ronments. Other than these, a few advanced techniques are
ing 40% less energy and up to 99% reduced water consump-            under experiment to further enhance the crop capabilities by
tion compared to outdoor fields [83]. Aerofarms, a leader           controlling their limitations with the help of advanced sensing
in VF, growing agricultural products with upto 390 times            and communication technologies. Among these methods, the
higher yields while utilizing 95% less water at Newark [84].        more prominent is phenotyping, which is based on emerging
   Under this farming method, many parameters are impor-            crop engineering, which links plant genomics with its eco-
tant, but CO2 measurements are most critical; hence,                physiology and agronomy, as shows in Figure 6. The progress
non-dispersive infrared (NDIR) CO2 sensors play a crit-             in molecular and genetic tools for various crop breeding was
ical role to track and control the conditions in vertical           significant in the last decade. However, a quantitative analysis
farms. Boxed Gascard, developed by Edinburgh Sensors [85],          of the crop behavior, e.g. grain weight, pathogen resistance,
is especially designed by considering such an environment,          etc., was limited due to the lack of efficient techniques and
which employs a pseudo dual beam NDIR measurement sys-              technologies that we can now enjoy.
tem to enhance the stability and reduced optical complexity.
Human hands are not required to touch the crops at any stage
when following the IoT-connected vertical farm; this is the
claim made by Mint Controls [86] developers who offer a
wide range of solutions, like waste containers and sensors
and their integration for various VF applications.
C. HYDROPONIC
In order to enhance the benefits of greenhouse farming, agri-
culture experts moved forward another step and provided
the idea of hydroponic, a subset of hydroculture in which
plants are grown without soil. Hydroponic is based on an            FIGURE 6. The process of phenotyping [96].
irrigation system in which balanced nutrients are dissolved
in water and crop roots stay in that solution; in some cases,          Research investigations, completed in [93], conclude that
roots can be supported by medium like perlite or gravel.            plant phenotyping can be highly beneficial to investigate
the quantitative characteristics, such as those are responsible                 Based on these facts, during the period of 2017 to 2022, the
for its growth, yield quality and quantity, and resistance                   global smart farming market is predicted to rise at a growth
capabilities to handle various stresses. Similarly, the role                 rate of 19.3% per year to touch $23.14 billion in 2022 [97].
of sensing technologies and image-based phenotyping are                      Here it is worth mentioning that UAV/drones are generating
highlighted in [94] and describes how these solutions can                    and further expected to generate the highest revenue amongst
help to boost the progress not only for screening numerous                   all agricultural robots utilized in smart farming (UAVs are
biostimulants but also their role in understanding the mode                  discussed in Section V). Evergreen demand for higher crop
of actions. Furthermore, an IoT-based phenotyping platform,                  yield, increased incorporation of information and commu-
CropQuant, is designed to monitor the crop and relevant trait                nication technology (ICT) in farming and the rapid global
measurements that can provide facility for crop breeding and                 climatic changes are some of the major drivers resulting to
digital agriculture [95]. Here, an automatic in-field control                such high market growth.
system was developed to process the data generated by plat-                     Manufacturers in the market offer a variety of products and
form. The provided trait analyses algorithms and machine-                    solutions, mostly based on sensors and efficient communica-
learning modeling help to explore the relation among the                     tion for a range of applications; a few are shown in figure 7.
genotypes, phenotypes, and environment where it grows.                       The key technologies and equipment’s that are currently
                                                                             available for this purpose are discussed in following.
11) EDDY COVARIANCE-BASED SENSORS                                            and mobile platforms worldwide [135]. Moreover, automatic
This type of sensors can be used for quantifying exchanges                   packet reporting system (APRS) is being integrated to report
of carbon dioxide, water vapor, methane or other gases, and                  telemetry data through satellite communication [136].
energy between the surface of the earth and the atmosphere.                     Table 1 lists a few sensors to provide the idea about their
This method offers an accurate way to measure surface-                       possible uses and the environment where they can be placed.
atmosphere fluxes of energy and trace gas fluxes over a
variety of ecosystems for, most importantly, agricultural                    TABLE 1. Some selected sensors and their possible uses in IoT based
                                                                             agriculture.
applications [121]. Currently, the sensors based on this tech-
nology are preferred over other similar options, like the close
chamber, due to high precision and its ability to measuring
continuous flux over large areas [122].
focusing on the grower’s requirements. With the advancement        ultimately, its success. In some crops, this is done a single
of technology, most of these manufacturers are offering trac-      time while, in some others, performed several times, even
tors with automatic-driven and even Cloud-computing capa-          on a daily basis, as crop reaches a certain stage. Harvesting
bilities. This technology is not new, as self-driving tractors     the crop at the right time is very critical, as doing so either
have been in the market even before semi-autonomous cars.          early or late can affect the production significantly. When
One of the main advantages of self-driving tractors is their       talking about the labor, it is estimated that the US faces a
ability to avoid revisiting the same area or row by reducing       $3.1 billion decline in crop production on a yearly basis due to
the overlap even less than an inch. In addition, they can          labor shortage [164]. Not only this, but, according to a study
make very precise turns without a driver’s physical presence.      conducted by the United States Department of Agriculture,
This facility offers better precision with reduced errors, espe-   overall 14 % of farm costs go to wages and labor costs,
cially when spraying insecticide or targeting weeds; those are     while it can be upto 39% in some labor intensive farms [165].
mostly unavoidable when a human controls the machinery.            Considering the worth of this stage and labor issues, farm
   Although, at the moment, no fully autonomous tractor            experts expect that involvement of agriculture robotics may
is available in market, many researchers and manufactures          not only ease the labor pressure but also provide the flexibility
are hardly working to mature the technology. Based on              to harvest whenever needed.
current progress and future demands of high-tech tractors,            In order to automate the harvesting process and make
it is predicated that around 700,000 tractors equipped with        it more precise, the role of robots has been increasing
facilities like autosteer or tractor guidance will be sold         over the recent decades. Considering the robot services,
in 2028 [158], while the same study expects that around            many researchers have done intensive research in order to
40,000 unmanned, fully-autonomous (level 5) tractors will be       mature the sensitivity of fruit detection, its shape, size, color,
sold in 2038 [159].                                                and localization [166]–[169]. Automatic harvesting of fruits
   When talking about such cultured machines, most farmers         requires deep investigation of sophisticated sensors that are
can’t afford to own them while most of the tractor service         capable of collecting precise and unambiguous information
providers and manufacturers operate well below their poten-        of that particular crop and fruit. The task of detecting the
tial. Considering the challenge, Hello Tractor has developed       right target in natural scenes is not simple since most of
a solution to sort these issues. The company has developed a       the fruits are occluded partially—sometimes even fully—
low-cost monitoring device that can be placed on any tractor,      under the leaves and branches or are overlapped with other
provides powerful software and analytics tools [160]. The          fruits [170]. Here, most of the prominent studies found in
benefits of this device are twofold- on one side it ensures        regard to this purpose are deeply based on computer vision,
that overall cost of tractor remains affordable for the most       image processing, and machine learning techniques. This
of growers while at the same time it monitors the condition        process needs very specialized and sophisticated tools to
of the tractor and reports if any problems occur. The soft-        differentiate the fruit conditions, as there are more than sixty
ware connects tractor’s owner to farmers in need of tractor        shapes, sizes, and colors for a pepper alone when it is ready to
services, just like Uber for tractors. Another major example       harvest. Considering such complexity, many robots are being
is Case IH’s Magnum series [161] tractor which uses on             developed for specific crops. Some of the leading robots
board video cameras and LiDAR sensors for object detection         being used for crop harvesting include SW 6010 [171] and
and collision avoidance. Recently, Case IH used this tractor       Octinion [172] for strawberries, SWEEPER robot [173] for
to plant soybeans by following the concept of autonomous           peppers, and FFRobot [174] for tree-based fruits like apples
tractors. In another development made by standards group           which can pick up to 10,000 fruits per hour.
ETSI where world’s first tractor connected to a car in France,        Strawberries are one of the most consumed fruits, avail-
using IoT [162] to control the accidents due to farm vehicles.     able mostly throughout the year while labor is the major
   After collecting all the important crop data, the next          contributor to the high cost of this fruit, especially during
step is pushing computing from the Cloud to the edge,              harvesting and packaging stages [175]. As the strawberry
as John Deere [163] wants. In their proposed system, an ana-       farms are grown mostly under greenhouse systems hence
lytics engine works locally on the farmer’s tractor rather than    the harvesting robots are designed to move on defined paths
in the Cloud in order to adjust the local inputs. For this         like rails where the translational motion is restricted and
purpose, they considered all the existing analytics and recom-     robots can move backward and forward only. Robots devel-
mendations to modify the current data in real time depending       oped by Agrobot are able to collect strawberries along the
on the field conditions. Based on this phenomenon, the man-        side of strawberry plant rows in the field, further packed by
ufacturer is bringing their tractors to next level by connecting   human operators [176]. For example, SW6010 by Agrobot is
their machine to the Internet and creating a method to display     a specialized and semi-automatic robot towards the specific
the information wherever farmer wants to see it.                   task of strawberry harvesting [177]. Tektu T-100 is an all-
                                                                   electric rechargeable strawberry harvester run silently with
C. HARVESTING ROBOTS                                               zero emission inside the poly-tunnels [178]. The installed
Harvesting is the most critical stage during the production        pickers are able to position over the crop rows and gather the
process, as this last phase dictates the crop’s output and,        fruit quickly and efficiently, directly into punnets.
D. COMMUNICATION IN AGRICULTURE                                              technology has its own worth but the FMS also plays a critical
Communication and reporting the information on a timely                      role which must be custom designed considering the specific
basis are considered the backbone of precision agriculture.                  application requirements. Generally, based on communica-
The real purpose cannot be achieved unless a firm, reliable,                 tion data rates and power consumption, wireless sensors for
and secure connection among various participating objects                    agriculture applications are divided in three broad categories
is provided. To achieve communication reliability, telecom                   as shown in table 2.
operators can play a crucial role in the agricultural sector.
If we truly want to implement IoT on a large scale in the                    TABLE 2. Data and power specifications of wireless sensors commonly
                                                                             used for agriculture applications.
agriculture industry, we have to provide a suitably large
architecture. Here, the factors like cost, coverage, energy
consumption, and reliability are critical and have to be
considered before choosing the mean of communication.
Low-energy networks can provide connectivity only on one
site and mostly do not offer services in remote areas where
sensed data need to be transmitted to the farm management
system (FMS). Depending on availability, scalability and
application requirements, various communication modes and
technologies are being used for this purpose, most common
are discussed here,
1) CELLULAR COMMUNICATION
Cellular communication modes from 2G to 4G can be suit-
able, depending on the purpose and bandwidth requirement;
however, the reliability, and even availability, of a cellular
network in rural areas is a major concern. To tackle this,
data transmission via satellite is another option, but, here,
the cost of this communication mode is very high, which                      2) ZIGBEE
makes it not suitable for small- and medium-sized farms. The                 Zigbee is primarily designed for a wide range of applications
choice of communication mode also depends on application                     especially to replace existing non-standard technologies.
requirements, such as some farms required sensors that can                   Depending on the application requirements, the devices based
operate with low data rate but need to work for long periods                 on this protocol can be one of three types including Coordi-
hence demand long battery life. For such scenarios, a new                    nator, Router and End User. Further, three different topolo-
range of Low Power Wide Area Network (LPWAN) is con-                         gies are supported by Zigbee networks named, Start, Cluster
sidered a better solution for cellular connectivity, not only                Tree and Mesh [34]. Based on these characteristics, and
in terms of long battery life but also a larger connectivity                 further considering the agriculture application requirements,
range with affordable rates (2 to 15 USD per year) [179].                    Zigbee can play vital role especially targeting the greenhouse
Currently, crop and pasture management are two of the main                   environment where usually short range communications are
applications where LPWAN networks are highly suitable,                       required. During monitoring the various parameters, the real
and, further considering its success, it can be utilized in many             time data from the sensor node is transferred through Zigbee
other farming-related uses.                                                  to end server. For the applications like, irrigation and fertiliza-
   Besides WAN connectivity option, many short range and                     tion, Zigbee modules are networked for communication, e.g.
medium level communications are being used in mesh net-                      in drip irrigation used to monitor soil contents like moisture.
works [180]. For example, a mesh-network of sensor nodes                     Further, SMS is forwarded to the farmer to update about the
collects data and transmits it to the gateway which is located               field data where GSM is required at long distance or Blue-
somewhere in the same area. The gateway further sends this                   tooth module can help at the shorter distances.
data to the farm management system using the WAN net-
work. The communication technologies used within the mesh                    3) BLUETOOTH
networks vary e.g. Bluetooth and Zigbee can be used to pro-                  Bluetooth is a wireless communication standard that connects
vide connectivity for peer-to-peer wireless communications.                  small-head devices together over shorter distances usually
From here, the sensed data forwarded to the FMS, which                       cooperating in a close proximity. Due to its advantages of low
gathers and analyses the information about all the activities                power requirements, easy to use and low cost, this technology
happening at different parts even the historical data regarding              is being utilized in many smart farming applications. Further,
the weather and climate updates, economic, products being                    Bluetooth making advancements in many IoT systems with
used and their specifications etc, in short making it decision               the release of Bluetooth Low Energy (BLE) or commonly
farming. It is important to mention that, the communication                  known as Bluetooth Smart. The study conducted in [181]
which tests Bluetooth and PLC (programmable logic con-             need to transmit data at the same time, as experiments done
troller) with ICS (integrated control strategy), timer control     in [188].
and soil moisture control approach for smart irrigation. The          Figure 8 gives an idea that how end-to-end communica-
target of this study is to find an optimum utilization of          tion possibilities can be divided in various layers to interact
water and energy consumption for various greenhouse or field       with each other in order to provide the services for smart
applications. A moisture and temperature sensor based on           agriculture.
BLE is developed in [182] especially focusing on the agri-
culture environments and weather conditions of crop fields.
Here the reason of choosing BLE for communication purpose
is due to its inherent support for smart phone accessibility.
Further, a similar effort is done in [183] where a new sensor
node is designed to monitor ambient light and temperature
employing BLE communication protocol preferable for IoT
based agriculture applications. Other than short range, WiFi
is utilized whenever LAN communications are required in
smart agriculture. Along short range connectivity, WiFi is uti-
lized whenever LAN communications are required in smart
agriculture. Study presented in [184] investigates a remote
monitoring system using WiFi, where the sensor nodes were
based on WSN802G modules. The deployed nodes commu-
nicate wirelessly with a central server, which is responsible
to collect and store the monitored data and further allow
displaying the information after required analysis.
smartphone crop applications. These researchers mostly                       TABLE 3. Smartphone based sensors that being used in various
                                                                             agriculture applications.
belong to developing nations, as proposed systems are
based primarily in countries like Kenya [193], [194],
Ghana [195], [196], Nigeria [197], [198], Mali [199],
Uganda [200], and Zimbabwe [201], [202]. Although,
the scope of smartphone utilization in agriculture has
been more commonly observed in Africa, experiments
in countries like Cameroon [203], China [204], [205],
Turkey [206], [207], and India [208], [209] are also increas-
ing. Analysing the success of m-services depends on many
factors. One of the most comprehensive studies regarding
the use of mobile phones for various agriculture applications
was conducted to review all the important factors [210]. This
study concludes that the service will be of no effect if the
developer of the application does not truly understand the
farmer needs.
   Obviously, the most important factor for such applications
is that the farmer should access and use them. In other words,
an easy-to-use, free or low-cost app that supports various
languages could attract the farmer’s attention. In addition,
developers should study and consider the relevant factors
before making their suggestions. For example, market prices
are of great interest to farmers, but would be of no use in
cases of bad roads and unavailability of proper transport vehi-
cles. The developers should target the problems of the wider
community instead of focusing only on farmers, considering
the transporters, brokers, and other agriculture experts as
well. Unfortunately, most of the applications are developed
on growers’ perceptions, instead of using independent and
verified market data. For this purpose, the developer should
not only focus on the data retrieved by independent investiga-
tors but also assess it under various usage patterns covering
longer durations.
   Table 3 lists smartphone based sensors that are attracting
the researchers to utilize them for various agriculture pur-
poses. While, last column provide some of the references
where these sensors have been used. Further, Table 4 includes
some of the important mobile apps developed for various agri-
culture applications along their features and achievements.                  (for example, on farming and the processing of agricultural
                                                                             products). To make it more effective, the scenario can be
F. CLOUD COMPUTING                                                           extended further to include access to consumer databases,
Precision agriculture is showing its potential and benefits by               supply chains, and billing systems.
improving agricultural operations through better data-driven                    Surely, moving towards Cloud-based services offer oppor-
decision making. However, to continue this success, precision                tunities to explore advancements, but it comes with new
agriculture not only requires better technology and tools to                 challenges, as well. First, a vast range of sensors are being
process data efficiently but also at a reasonable cost such                  developed and used in precision agriculture, each of which
that the received data can be used to make field decisions                   has its own data format and semantics. Secondly, most of
efficiently. For this purpose, farmers can use Cloud services                the decision-support systems are application-specific while,
to access information from predictive analysis institutes so                 on the other hand, a farmer can be in the need of accessing var-
that they can choose the right product available according to                ious systems for a specific application, e.g., soil monitoring.
their specific requirements. Cloud computing offers an edge                  Considering both of these cases, the Cloud-based decision-
to farmers to use knowledge-based repositories that contain                  support system not only needs to handle the diversity of data
a treasure of information and experiences related to farming                 and their formats but also must be able to configure these
practices as well as on equipment options available in the                   formats for different applications.
market with the necessary details. In most cases, all this                      An open Cloud-based system has been established by
comes along with expert advice from a wide range of sources                  AgJunction [243] which gathers and disseminates the data on
a form from different precise agriculture controllers, leading               large areas in order to harvest data for further processing
to a decrease in costs and environmental impacts. Further-                   and analysis. Furthermore, UAVs, better known as drones,
more, ‘‘Akisai’’ Cloud [244], proposed by Fujitsu, focuses on                fitted with high-resolution cameras and precise sensors, can
food and agricultural industries and incorporates information                be flown over thousands of hectares of farms.
communication technology for increasing the food supply in                      The role of surveillance in all agriculture applications is
the coming years.                                                            highly critical, especially in forestry and crop monitoring due
   Similarly, SourceTrace developed and offering Cloud-                      to the need to cover large areas [246]. Therefore, a fast, low-
based mobile applications to provide visibility and relations                cost, real-time, and large-scale surveillance supported with an
between farms and markets, further tracking the value chain at               accurate data acquisition and transmission facility is crucial
the source, e.g., ’eService Everywhere’ [245]. An important                  for agriculture production. Currently, mostly two options are
note about their applications is that, during the development,               used to obtain aerial images of a field area: satellite and
they considered the farms’ remoteness and low bandwidth                      airplanes. Both of them are good for a macro view of a
environments.                                                                landscape, but they face serious issues in terms of quality
   Figure 9 presents possible infrastructure and relationship                when it comes to micro views. These macro-view images are
scenario of fluid computing including Edge, Mist and Fog                     not good in resolution and cannot offer the image quality
for smart agriculture.                                                       which is required during the analyses and decision mak-
                                                                             ing. Secondly, not only the resolution but visiting frequency
                                                                             also matters and, through both of these, it is not simple to
                                                                             take and collect images frequently (on average, four times a
                                                                             month [247]). Another serous issue is that these operate above
                                                                             the cloud level where there is a strong possibility that both are
                                                                             obstructed in bad weather.
                                                                                When we talk about UAVs that provide an ‘‘eye in sky’’,
                                                                             we can overcome— or even eliminate— the above mentioned
                                                                             issues when we consider the micro views. The quality of
                                                                             images taken through UAVs depends on the attached camera’s
                                                                             resolution—normally dozens of times better than satellite
                                                                             images—and, most importantly, we can adjust according to
                                                                             application requirements. More specifically, UAVs supports
                                                                             faster and better NDVI to assess crop conditions, like weed
                                                                             mapping, leaf assessments, etc., and provide immediate feed-
                                                                             back so that farmers can take timely actions. Similarly, UAVs
                                                                             are better in terms of frequency, even if requires multiple
                                                                             times in a single day, and are also the option least affected by
                                                                             weather conditions, unless it is raining. Due to the mentioned
                                                                             advantages, UAVs are considered the future of precision
                                                                             agriculture, and this is the reason they are generating the
                                                                             highest revenue amongst all agricultural robots developed for
                                                                             precision agriculture. According to quoted figures by a report
                                                                             published by FAO in 2018, it is estimated that the agriculture
FIGURE 9. Fluid computing infrastructure for smart farming.                  drone-related market to be worth USD 32.4 billion [248].
                                                                                The current condition of the entire field is one of the most
                                                                             valuable pieces of information to obtain in the precision pro-
V. UAVs IN AGRICULTURE                                                       gram. With the help of this collected data, a farmer can spot
Recently, the IoT has made remarkable progress in many                       problems early and rapidly; hence, appropriate interventions
industries, including farming sectors like poultry, fishing,                 can be applied. Agricultural drones represent a new way to
etc. but when we talk about agriculture, the communication                   collect field-level data; the results are on-demand whenever
facilities like base stations or Wi-Fi are very limited, which               and wherever needed, as the drone can be easily and quickly
prevents the growth of the IoT in this sector. Such commu-                   deployed. Most importantly, it is not all about their hardware
nication infrastructure and related facilities are even worst in             but the convenience, quality, and utility they are offering,
developing counties and rural areas, which is one of the major               as the drone-enabled surveillance offers the real facility to
hurdles when introducing the IoT in the agriculture industry.                have an idea of what is happening in the farm fields at that
The data acquired through the wireless sensors cannot be                     moment.
transmitted in the absence of reliable communication infras-                    The UAVs, used for agricultural applications usually fall
tructure. In such a scenario, UAVs offer an alternative, as they             into two categories: fixed-wing and multi-rotor drones [249]
visit and communicate with the wireless sensors spread over                  (figure 10). Although both are available in various ranges
FIGURE 11. NDVI based water stress map of 160 acre walnut orchard [258].
through the long cable, is provided so that it can fly as long               like its geometry and nutrients ultimately help to optimize
as you have power backup on the ground, most importantly it                  the crop management operations.
doesn’t require to lift heavy batteries.
   Currently, agriculture is being considered one of the most                D. IRRIGATION
favorable fields where UAVs can offer solutions to resolve                   Use of drones for irrigation applications is, again, two-fold.
many dominant and long-lasting issues. Some of key areas in                  On one side, equipping UAVs with a variety of sensors
which drones are already playing key roles to assist farmers                 and cameras can help to identify areas that are under water
throughout the crop cycle are highlighted below.                             stress and conclude what irrigation changes are required.
                                                                             At the same time, they can be used for sprinkling water and
A. SOIL AND FIELD ANALYSIS                                                   pesticides on the crops precisely, especially in emergency
Drones are able to produce precise information to analyze                    cases, which would save both time and wastage. In [272],
the soil before sowing the crop, which helps to determine the                multispectral images of citrus crops were acquired using the
most suitable crop for specific land; furthermore, it suggests               fixed-wing UAV, where the retrieved data was used to assess
the seed type and its planting patterns. In [261] authors shared             and detect structural and physiological changes in the targeted
their experimental results using Sirius I, a fixed-wing aircraft,            crop. Further, [273], [274] are similar efforts in which UAVs
affixed with a Lumix GF1 digital camera by Panasonic to                      were used to estimate the crop water stress. Furthermore,
capture images from different sites to monitor the soil erosion              UAVs are not only used to analyze the irrigation properties but
issues in Morocco. Similarly, authors in [262] targeted the                  also provide solutions by sprinkling water precisely over the
issues of soil analyses where they used Lumix DMC-LX 3 to                    water stress areas as in [275]. Due to this application of UAVs,
take the images and Pix4UAV for mapping the results.                         they are being considered the newest water-saving tool,
                                                                             while their use is helping not only to increase watering effi-
                                                                             ciency but also detect possible pooling or leaks in irrigation.
B. PLANTING
                                                                             Examples like ’JT20L-606’ [276] and ’AGRASMG-1’ [277]
Millions of acres of land are currently under-utilized due                   are specialized drones that were developed and are being used
to being human inaccessible or lack of suitable workers.                     for this purpose.
Safety concerns of rough terrain are main reason not to utilize
these areas for forestry or agriculture purpose. For this pur-               E. PLANT COUNTING AND GAP DETECTION
pose, drone based planting systems are being developed that                  Precision agriculture critically needs the spatial data on crop
decrease planting costs upto 85 percent [263]. Not only cost,                density when making decisions during various applications.
but within shorter time as some recently developed drones can                The quantity and plant numbering not only reflects the field
plant 100,000 trees in a single day [264]. These systems shoot               emergence but allows better and more precise assessment
pods which include the seeds and necessary nutrients required                of the yield production, in fact, determining the crop fate.
to grow the plant. This method is found very effective for                   Again, UAVs are offering flexible solutions for this pur-
rough terrain; most importantly the success rate is more than                pose. In [278], authors performed digital counting of Maize
75% [265]. Due to the success and flexibility they offer, UAVs               plants with the help of UAVs. Further, in [279], authors
are being considered the best candidate for plantation all                   proposed a method in which they used UAVs to estimate
over the world, from NASA engineer [266] to countries like                   the density of wheat plants at the emergence stage while a
Pakistan [267] and India [268].                                              Sony ILCE α5100L RGB camera was used to take the
                                                                             images.
C. CROP MONITORING
Crop monitoring is one of tough jobs and facing low effi-                    F. SPRAYING THE PESTICIDES/HERBICIDES
ciency due to covering large area. Drones are offering the                   Similar to irrigation, UAVs can be used to spray herbicides/
solutions by allowing real-time monitoring of far farms, more                pesticides on crops, but their use for these applications is
accurately and cost-effectively comparing with previously                    more critical. Spraying application would be highly efficient
used satellite imagery. The Microdrones +m [269] is an                       compared to current procedures; herbicides/pesticides are
accessory toolkit which provides aerial imaging facility to                  usually sprayed over the entire farm, which is not required in
observe the crop nutrients, moisture levels and monitoring                   most cases. If using an UAV to spray herbicide, it can spray
of other necessary parameters. A study conducted in [270]                    directly on the unwanted weeds or can target the affected
where authors used UAVs along digital camera to monitor                      areas only. Furthermore, as spraying using drones would be
the crop conditions. The purpose of the study was to find                    highly targeted, the drone would figure out and spray as
the relationship between the crop spectral characteristics and               per requirements, helping to reduce the overall expenditures.
effect of fertilizer availability for plant health. Further, [271]           Handling the sudden environment changes like wind direc-
presents an innovative procedure to compute and map the                      tion or speed is another issue for an UAV especially when
3-dimensional geometric characteristics of trees and tree-                   being used for spraying applications. For this purpose, [280]
rows. The generated maps can be helpful to understand the                    proposed a computer based system that autonomously adopt
relation between the trees’ growth and field related factors                 the UAV control rules to keep precise pesticide deposition.
G. HEALTH ASSESSMENT                                              existing available food safely and efficiently to more people
Scanning crops with visible and Infrared (IR) light sensors       is the real subject of issue of the food industry [289].
fitted on drones can identify which plants may be infected           A comprehensive report regarding the future food require-
by bacteria or fungus. Using UAVs, this can be done fre-          ments published by World Resources Institutes (WRI)
quently and with flexibility. The early detection of any such     in 2018, highlights that we need sustainable food industry to
issues helps to prevent the disease being spread to other         feed 10 billion people by 2050. The report suggests a five-
plants or crop areas. Multispectral images can help to detect     course menu of solutions to tackle the future food issues
the disease or sickness at early stages even before reaching      where ‘‘reduction in food losses and waste’’ is declared as
the level in which it is possible to detect with the human        the first and most important course [290]. Further it conclude
eye. Experiments done in [280] present the data collection        that, reducing the food loss and waste only by 25% can
campaign performed over a sorghum crop which was severely         help to reduce the food gap by 12%, the land gap by 27%
damaged by white grubs. Further, in [281], UAVs are used to       and greenhouse gas mitigation gap by 15%. To have better
collect data from ground-based sensors, including a chloro-       idea, detailed figures about the food loss are highlighted
phyll meter, water potential meter, and spectroradiometer,        in figure 12 based on various geographical locations and
and the collected information was used to evaluate the plant      considering the stages along food supply chain where these
health and crop condition, ultimately reflecting the ground       losses are occurring.
truth.
dioxide in terms of negative effects. In short, every which way                 To provide the recommended environment, a device with
you look at it; food waste is a major culprit in destroying our              supported technology can be installed at the storage site, even
planet.                                                                      in transport trucks. Further, it is linked to an online dashboard
   Among all perishable food produced in the world today,                    that can be configured to send alerts in the event of abnormal
only 10% is preserved properly [295]. When we talk about                     temperature levels to trigger swift remedial action. Some of
most of the developed countries, a robust food cold chain                    key technologies available for this purpose and their use cases
is maintained where essential quality checks are followed,                   are mentioned here.
entailing temperature-regulated refrigerated warehouses to
refrigerated trucks to ensure that food gets from farm to                    A. COMPLIANCEMATE
market safely. On the other hand, many developing countries                  Compliance with hazard analysis and critical control points
lack such proper cold chain infrastructure, simply resulting                 (HACCP) offers a food safety and quality monitoring pro-
the majority of food spoiling when being transported to the                  gram which collects temperature data inside coolers and other
end-user. Considering this fact, there is a huge opportunity                 kitchen equipment continuously. For example, its integration
to cut food waste and improve food distribution by simply                    with Touchblock is used to capture temperatures in coolers
implementing a controlled-temperature transportation sys-                    and prep rooms at every minute [297].
tem. Based on the facts, one can conclude that increasing
food production is not sufficient to achieve food security,                  B. LAIRD’S SENTRIUS
but, rather, some practical actions are required to find skillful            A battery-powered and long-range integrated sensor platform
ways for efficient distribution of the already available food.               that leverages the benefits of LoRaWAN and Bluetooth Low
   There are different ways to monitor and control food tem-                 Energy (BLE) connectivity. It provides LoRaWAN options
perature. The manual method of checking a thermometer                        at 868/915 MHz, based on the Semtech SX1272 and Nordic
and recording the temperature has many drawbacks, where                      nRF51 silicon. Further, it offers high RF performance in a pre-
someone must actually do it and, most importantly, take                      cise temperature and humidity. Two major series, including
the readings correctly. On other side, implementing an auto-                 RS1xx and RG1xx (multi-wireless gateways), work together
matic method that uses wireless sensors to electronically                    in order to provide Cloud-based services. Most importantly,
measure and record temperatures can substantially improve                    it requires an inexpensive endpoint radio and a more sophis-
food safety. This method allows for a continuous data stream                 ticated base station to manage the network. As compared to
of temperatures simply—24 hours a day, 7 days a week.                        LoRa, Sigfox communication tends to be better if it is headed
By doing so, temperatures can be recorded consistently                       up from the endpoint to the base station. Although it supports
and on time, leaving little room for interpretation; in short,               the bidirectional functionality, its capacity going from the
the entire process is based on facts and nothing more. Further,              base station back to the endpoint is constrained, as it provides
utilizing the recent technologies, the recorded data can be                  less link width going down than going up.
stored in the Cloud and accessed via any type of internet-
connected device. Notifications can be established that will                 C. CCP SMART TAG (RC4)
send real-time alerts if the temperature strays outside preset               CCP claims to be a complete monitoring solution for the
limits, allowing for immediate action to remedy the situation.               food service and food retail industry [298]. It is capable to
Further, IoT offers predictive maintenance and indicate when                 automate the temperature environment which meets the food
the monitoring equipment itself is going to end its useful                   safety regulations suggested for various food items.
life so it can be replaced before it fails and compromises                      Further, temperature and other data are interpreted and
product quality. These are only couple of scenarios, now if                  viewed on a service provider Cloud platform via web and
we consider the figures presented in figure 12, IoT has the                  mobile applications.
potential to monitor and keep the food quality at every stage
of the supply chain, from production to consumption.                         D. TEMPREPORTER
   A research study conducted by Indian School of                            In compliance with HACCP (Hazard Analysis and Critical
Business in which students worked with a local grower to                     Control Points), it is used to monitor temperatures 24/7.
transport fruits and vegetables in refrigerated trucks from                  Further, it logs the readings automatically. Reports are auto-
Punjab to Bangalore, a distance of more than 2,500 km                        filled by considering HACCP & HPRA (Health Products
through rough roads under high temperatures. The results                     Regulatory Authority) recommendations regarding tempera-
were highly encouraging to implement the cold chain to                       ture monitoring.
transport the agriculture products. The out of conducted study                  According to Finistere Ventures report, as of 2018, around
brought benefits in three ways: (1) increased food shelf-life                $2 billion has been invested globally in AgTech. Several
from one week to two months; (2) an up to 23% higher                         investments are expected to cross these figures in 2019.
profit for everyone linked in the supply chain was observed;                 Considering the future needs of IoT in agriculture applica-
(3) a 76% reduction of food wastage (post-harvest). Besides                  tions, almost all leading technological giants are supporting
all this, another critical factor is the emission of greenhouse              this progress in their own way. Table 5 provides a list of sev-
gases was observed to be reduced by 16% [296].                               eral of the leading global organizations who have proposed
TABLE 5. Current status and future vision of major technological giants regarding the iot in agriculture industry.
TABLE 5. (Continued.) Current status and future vision of major technological giants regarding the iot in agriculture industry.
advancements in technology, including sensors, communica-         their land is. Based on recent success, it is estimated that
tion methods, machines, and even robots. In fact, technology      more than 75 million IoT-based devices will be operating in
has proved this already, as, in most developing countries;        the agriculture industry by 2020. Further, the average farm is
more than 50% of the population is somehow engaged in             expecting to generate 4.1 million data points on a daily bases
the agriculture industry yet are far behind in providing both     by 2050 [316].
the quantity and quality when compared with the developed
countries, where less than 2% of the population is perform-       B. COMMUNICATION
ing much better. The difference is clear, as countries like       Real success of IoT in agriculture largely depends on
Australia, the US, and most of Europe are pioneers to employ      advances in connectivity. From telecom’s perspective, pro-
the advanced tools and methods multiplying the crop yields        viding mainly connectivity and other value-added services
during the last five decades. These comparisons show that         has an immense potential and can influence the entire chain
recent technologies and advanced methods are making the           greatly [317]. Most of the telecom operators around the globe
farms not only highly profitable but safe and environmentally     offer connectivity services, but such services only represent a
friendly.                                                         tiny amount of the entire smart agriculture market. Consider-
   Considering this scenario, future agriculture is expected      ing its worth, especially in rural areas, the cellular operators
to evolve as a high-tech industry where interconnected sys-       have to offer a new range of services targeting the growers’
tems will enjoy the luxury of artificial intelligence and         demands. Accepting the fact that most of the community
Big Data facilities. The resultant systems will converge into     belong to this industry are not highly educated and mostly
a single unit where farm machinery and management, start-         unaware of new technologies, hence the operator should
ing from seeding to production forecasting, are combined.         provide end-to-end solutions other than just providing the
By involving the advanced technologies like agricultural          connectivity. If so, then it will certainly help to increase the
robots, Big Data, and cloud-computing artificial intelligence,    market share of mobile and telecom operators. Further, these
agriculture can create a new era of superfusion. Following are    operators need partnerships with the investors to provide end-
some of the key technologies and methods that need to apply;      to-end solutions, which demands higher investment, even
focusing to achieve sustainable future agriculture.               before advantages can be seen. The results of success when
                                                                  inviting the investors depend on the nature of the partnership
A. WIRELESS SENSORS AND THE IOT                                   and the involved bodies, like device manufacturers, solution
Wireless sensors placed strategically around fields are provid-   providers, non-cellular connectivity service providers, sys-
ing farmers with up-to-date information in real time, allowing    tem integrators, etc. On one side, the outcome of this partner-
them to adapt the care that the crops need, which results         ship would help operators to enter deeper into the industry,
in higher food production with less waste. Wireless sensor        ultimately boosting their market share. At the same time,
networks (WSNs) are also being used to inform farmers             this opportunity can create strong relationships among the
about nearly all aspects of their crop growth as well as about    organizations and farmers to help to educate them about the
the readiness state of the farm’s machinery, thus, helping in     benefits of smart agriculture.
preventing loss of crop as well as enhancing the readiness of        The success of cellular technology is only possible when
the equipment which cultivates it. WSNs with GPS capabil-         service providers leverage its real benefits like portability,
ity are helping tractors in compensating for uneven terrain       flexibility and luxury of two way communication to offer
and optimizing land preparation for growing crops. Recently,      low cost but customized solutions. They must provide what
advances in image recognition and digital signal processing       the farmer is in need, at the place they choose. Furthermore,
gave even more capabilities to WSN to accurately determine        to provide fast penetration in agriculture industry, policy
crop quality and health.                                          changes are required in order to provide access of reliable
   In order to make agriculture sustainable, the use of the IoT   and quality inputs. The research conducted in [172] which
will be at the center and forefront in agricultural operations.   considers 23 studies where mostly belong to developing
This includes everything from water and power usage, crop         countries, concludes that the cellular services and smartphone
transportation, farm machinery operation and maintenance          technology carry a promising future for smallholder farmers
alerts, and market price updates. The IoT has the capability      being capable to improve their yields.
to make these tasks streamlined and more predictable by              Furthermore, licensed LPWA (low-power wide-area) tech-
recognizing the crop’s needs at every stage. It has already       nology is expected to be a game changer for smart agri-
proved a breakthrough and is further going to change the          culture. Due to its characteristics and supported services
way we look at various agriculture activities by providing the    including low power consumption and efficient coverage are
farmer control over their land and assets in an unprecedented     well suited to the geography and economics of agriculture
way, thus, maximizing their effectiveness and efficiency.         hence expected to play a critical role in future smart farming.
Further, the future of the IoT can be shaped by the phenom-       Consequently, narrowband IoT (NB-IoT) got strong industry
enal advances in WSNs and the fifth generation (5G) of cel-       support and becoming an effective global standard for LPWA
lular mobile communication technologies to provide farmers        connectivity. It has the potential to provide major connectivity
with real-time data and information anytime and everywhere        changes in agriculture industry by changing the perceptions
about Internet capabilities. Believing in its future success,                One of them is power issue as due to its nature; smart farming
it is expected that leading cellular operators with strong IoT               requires wide use of energy. Among the main reasons of
ambitions can generate significant revenues by providing                     extensive power consumption some are including, long term
smart agriculture services when collaborating with LPWA                      sensor deployment, use of GPS repeatedly and transmission
technology providers. In order to achieve long term success of               of sensed data via GPRS. Traditionally, farmers in remote
these short, mid and long range communication technologies,                  areas have bought and utilized renewable energy sources
necessary steps for infrastructure construction are required                 randomly and at a hefty price, which has limited their ability
towards attaining the technology-based agriculture.                          to use them in farming to a great extent. However to solve
                                                                             the power issues in long term, deep analysis of power con-
C. UAVs AND OTHER ROBOTS
                                                                             sumption sources like remote data transmission can help to
Drones are being widely used by farmers for crop growth                      tackle the problem at some extent. Further, smart grids and
monitoring and as a means to combat hunger and other                         microgrids, however, lend themselves to seamless integration
harmful environmental impacts. Furthermore, they are being                   of distributed energy sources (DERs), thus, making them
used to spray water and other pesticides efficiently, consid-                appealing for adoption by farmers. The emergence of smart
ering the tough terrains, especially when the crops possess                  power meters has further given the farmers the confidence
different heights. Drones have proven their value, not only                  to invest in DER, especially since they have the option to
in terms of spraying speed but precision, as well, when                      sell the excess power to the grid. Recent advances in energy
compared with traditional machinery of same purpose. With                    storage devices, integrated electricity and heat systems will
recent advances in swarm technology and mission-based con-                   make DER even more attractive for farmers, as they will be
trol, groups of drones equipped with heterogeneous sensors,                  able to store energy and use the heat generated by cooling and
including 3D cameras, can work together to provide farmers                   heating when needed. However, healthy investment require-
with comprehensive capabilities to manage their land. With                   ments and public perceptions are two other barriers on the
the inclusion of UAVs in agriculture, farmers are able to put                way to making these solutions successful.
their eye in sky, but many challenges need to be addressed
in order to enjoy the real advantages of this technology,                    F. HYDROPONICS AND VERTICAL FARMING (VF)
especially the integration of other technologies and how to                  Other than employing the advanced technologies, new agri-
use them in poor weather conditions.                                         cultural practices can be very crucial to overcome the geo-
   Beside drones, robotics within agriculture have improved                  graphic and resource limitation challenges. On one side,
productivity and resulted in higher and faster yields. Such                  arable land is shrinking, and, at the same time, it is estimated
robots, like spraying and weeding robots, are reducing agro-                 that three million people around the globe are migrating
chemical use. Robots equipped with laser and camera guid-                    to cities, resulting in more pressure on the existing limited
ance are being used for identifying and removing weeds                       urban resources [318]. Considering this rapid migration, it is
without human intervention. They navigate between rows                       estimated that by 2030, 60% of the world’s population is
of crops on their own, ultimately increasing the yield with                  going to depend on cities, and this number is further expected
reduced manpower. More recently, plant-transplanting and                     to rise to 68% until 2050 [319]. Considering both of these
fruit-picking robots are emerging to add a new level of                      issues, it could be disaster for food production in the near
efficiency to traditional methods.                                           future with current agriculture practices. VF is an answer of
D. MACHINE LEARNING AND ANALYTICS                                            these issues, as it meets the challenges of land and water
Machine learning and analytics are used to mine data for                     shortage and, at the same time, looks highly suitable to
trends. In farming, machine learning is used, for example,                   be adopted near the cities. VF is portrayed as the answer
to predict which genes are best suited for crop production.                  to the looming shortage of food and shrinking arable land,
This has been giving growers all over the world the best seed                at least in some areas of the world. Further, hydroponics can
varieties, those which are highly suitable to respective loca-               play a key role, as this method lowers the requirements of
tions and climate conditions. Machine-learning algorithms,                   water and space to a great extent. Rapid growths in computer
on the other hand, have indicated which products are of high                 power are propelling scientific discoveries in plant nutrition
demand and which products are currently unavailable in the                   and growth that would make VF even more appealing to
market. Thus, for the farmer, this has given valuable clues for              growers.
future farming. Recent advances in machine learning and ana-                    Along VF and hydroponics, new and advanced solutions
lytics will make it possible for farmers to accurately classify              are required to increase the arable land without disturb-
their products and weed out less desirable crops before they                 ing the forests and other natural animal habitats. For this,
arrive to customers.                                                         we have to focus on the deserts as these cover one third of
                                                                             the Earth’s land surface. The solutions are started already as
E. POWER CONSUMPTION, RENEWABLE ENERGY,                                      Norwegian and Chinese firms/experts are doing efforts in
MICROGRIDS, AND SMART GRIDS                                                  Dubai, Qatar, Jordan and Chinese deserts [320]–[322].
Despite its future opportunities, smart agriculture facing                      Agriculture is not just an industry; in fact, it provides the
some limitations that are holding back the growth of IoT.                    basis of human society, as the goal is not just to grow crops,
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                                                                                    de Techniques Avancées Bretagne (ENSTA Bretagne), Brest, France. He
                                                                                    has published more than 170 refereed publications. His H-index is 27. He
                          MUHAMMAD AYAZ received the M.S. degree                    is the author of a book and the coauthor of three other books and four
                          in computer science from SZABIST Islamabad                book chapters. During his career, he had successfully supervised several
                          Pakistan and the Ph.D. degree in information tech-        postdoctoral and Ph.D. candidates and M.Sc. students. His research interests
                          nology from University Teknologi PETRONAS,                include source separation, high-order statistics, signal processing, robotics,
                          Malaysia, in 2007 and 2011, respectively. He is           telecommunication, biomedical engineering, electronic warfare, and cogni-
                          currently an Assistant Professor and a Researcher         tive radio. He was the Vice President of the IEEE Signal Processing Society
                          with the Sensor Networks and Cellular Systems             in Western Australia for two years. He has also been the Lead Guest Editor
                          (SNCS) Research Center, University of Tabuk,              of the EURASIP Journal on Advances in Signal Processing.
                          Saudi Arabia. He led various research projects
                          funded by the University of Tabuk and the Ministry
of Higher Education, Saudi Arabia, especially related to water quality
monitoring. He is the author of many research articles published by the
IEEE, Elsevier, Springer, Wiley, and other well-known journals. His research
interests include mobile and sensor networks, routing protocols, network
security, and underwater acoustic sensor networks.
                                                                                                               EL-HADI M. AGGOUNE received the M.S. and
                                                                                                               Ph.D. degrees in electrical engineering from the
                                                                                                               University of Washington (UW), Seattle, USA.
                             MOHAMMAD AMMAD-UDDIN received the                                                 He has taught graduate and undergraduate courses
                             M.S. degree in computer networks from the                                         in electrical engineering at many universities in
                             COMSATS Institute of Information Technology,                                      USA and abroad. He has served at many academic
                             Islamabad, Pakistan, the M.Sc. degree in com-                                     ranks, including the Endowed Chair Professor,
                             puter science in software engineering from Bahria                                 the Vice President, and the Provost. His research
                             University, Islamabad, and the Ph.D. degree in                                    work is referred to in many patents, including the
                             wireless sensors network form ENSTA, Bretagne,                                    patents assigned to ABB, Switzerland, and EPRI,
                             France. He is CCNA and CCAI Certified. He              USA. He is currently a Professor and the Director of the Sensor Networks
                             is currently a Senior Researcher with the Sensor       and Cellular Systems (SNCS) Research Center, University of Tabuk, Tabuk,
                             Networks and Cellular Systems Research Centre,         Saudi Arabia. He is also a Registered Professional Engineer in the State of
University of Tabuk, Saudi Arabia. He taught many graduate and under-               Washington. He has authored many articles in the IEEE and other journals
graduate computer courses in a number of universities in Saudi Arabia and           and conferences. He has been serving on many technical committees. His
abroad. He led many research and development projects in the areas of wire-         research interests include power systems, wireless sensor networks, scientific
less sensor networks, underwater sensor networks, and smart agriculture.            visualization, and neural networks. One of the laboratories, he directed won
He is the author of many research articles published in the IEEE and other          the Boeing Supplier Excellence Award. He was also the winner of the IEEE
journals. He is listed as an Inventor in a patent registered in USA. His research   Professor of the Year Award at the UW Branch. He is listed as an Inventor in
interests include routing, clustering, and localization of sensors nodes in         a major patent assigned to Boeing Company.
wireless sensor networks.