Unit 3

Explain the any three 5G use cases along with the challenges and requirements

5G technology enables a wide range of applications due to its high speed, low latency, and
massive connectivity capabilities. Here are three major 5G use cases, along with their challenges
and requirements:
1. Autonomous Vehicles (Connected Cars)
Use Case: 5G enables real-time communication between vehicles (V2V), infrastructure (V2I),
and pedestrians (V2P), enhancing safety and efficiency in autonomous driving.
Challenges:
Ultra-low latency (1ms or less) is required to prevent accidents.
High reliability to ensure continuous connectivity in all environments.
Security concerns, as cyberattacks on autonomous vehicle networks could be catastrophic.
Requirements:
Ultra-Reliable Low Latency Communication (URLLC) to support instant decision-making.
Edge computing to process data closer to the source, reducing transmission time.
High network density to handle multiple vehicles in urban environments.
2. Smart Healthcare (Remote Surgery & Telemedicine)
Use Case: 5G allows doctors to perform remote surgeries using robotic systems and enables high-
definition video consultations in real-time.
Challenges:
Extremely low latency is needed for real-time robotic control.
Network downtime or signal loss could be life-threatening.
High data security is necessary to protect patient information.
Requirements:
URLLC to ensure real-time responsiveness in medical applications.
Network slicing to allocate dedicated bandwidth for healthcare services.
Redundant connectivity to avoid disruptions during critical operations.
3. Industrial IoT (Smart Factories)
Use Case: 5G enables real-time monitoring, automation, and predictive maintenance in smart
factories, improving efficiency and reducing downtime.
Challenges:
High initial deployment costs for 5G-enabled infrastructure.
Compatibility issues with existing industrial systems.
Reliable connectivity required in harsh industrial environments.
Requirements:
Massive Machine-Type Communication (mMTC) to connect thousands of IoT devices.
Private 5G networks to ensure uninterrupted operations.
AI and edge computing to analyze data in real-time for predictive maintenance .
 Unit 3

Explain 5G system concept consisting of three generic 5G services along with the four main
enablers
The three generic 5G services are:
• Extreme Mobile BroadBand (xMBB) provides both extreme high data-rate and lowlatency
communications, and extreme coverage. xMBB provides a more uniform experience over the
coverage area, and graceful performance degradation as the number of users increases. xMBB
will also support reliable communication for e.g. National Security and Public Safety (NSPS).
• Massive Machine-Type Communication (mMTC) provides wireless connectivity for tens of
billions of network-enabled devices, scalable connectivity for increasing number of devices,
efficient transmission of small payloads, wide area coverage and deep penetration are prioritized
over data rates.
• Ultra-reliable Machine-Type Communication (uMTC) provides ultra-reliable low-latency
communication links for network services with extreme requirements on availability, latency and
reliability, e.g. V2X communication and industrial manufacturing applications. Reliability and
low latency are prioritized over data rates
The four main enablers are:
1. The Dynamic Radio Access Network (DyRAN) provides a RAN that adapts to rapid spatio-
temporal changes in user needs and the mix of the generic 5G services. The DyRAN incorporates
elements such as
 Ultra-Dense Networks,
 Moving Networks (i.e. nomadic nodes and moving relay nodes),
 Antenna beams,
 Devices acting as temporary access nodes and
 D2D communication for both access and backhaul.
2. The Lean System Control Plane (LSCP) provides new, lean control signaling necessary to
guarantee latency and reliability, supports spectrum flexibility, allows separation of data and
control planes, supports a large number and variety of devices with very different capabilities,
and ensures energy performance.
3. Localized Contents and Traffic Flows allow offloading, aggregation and distribution of real-
time and cached content. Localization reduces the latency and the load on the backhaul and
provides aggregation of e.g. sensor information.
4. The Spectrum Toolbox provides a set of enablers to allow the generic 5G services to operate
under different regulatory frameworks, spectrum usage/sharing scenarios and frequency bands
 Unit 3

Explain Extreme mobile broadband generic 5G services in detail with respect to spectrum
access, radio interface for dense deployments, Spectral efficiency and advanced antenna systems,
Number of users, User mobility, Links to the main enablers.
 The Extreme Mobile Broadband (xMBB) generic 5G service extends today’s MBB
service and provides versatile communication that supports new applications requiring
higher data rates, lower latency and a more uniform user experience over the coverage
area;

 xMBB will provide extreme data rates, on the order of Gbps per user, to meet the
requirements of high-demand applications such as augmented or virtual reality, or
ultrahigh-definition video streaming. In addition to high user data-rates, lower latency is
also required, e.g. for Tactile Internet.

 In crowded areas, xMBB provides a graceful decrease of rate and increase of latency as
the number of users increases, instead of refusing service to some users  The extreme
coverage of xMBB and the DyRAN make it possible to establish reliable communication
for NSPS as a mode of xMBB, and provide connectivity when the infrastructure is
damaged, e.g. after a natural disaster.

 The xMBB service will also exhibit robustness with respect to mobility and ensure
seamless provision of high-demand applications with a QoE comparable to that of
stationary users even while traveling at high speeds in e.g. cars or high-speed trains.
Some of the key solutions to realize the xMBB are access to new spectrum and new types
of spectrum access, increased density of the network, improved spectral efficiency
including localized traffic, and higher robustness for mobile users.

 Links to the Main Enablers

Extreme Mobile Broadband relies on several 5G enablers to deliver its high performance:
 Millimeter-Wave (mmWave) Spectrum: Enables multi-gigabit speeds in urban areas.
 Massive MIMO & Beamforming: Improves spectral efficiency and network capacity.
 Network Slicing: Allocates dedicated network slices for high-bandwidth applications.
 Edge Computing: Reduces latency by processing data closer to the user
 Unit 3

Q.1With suitable diagram explain Ultra-reliable machine-type communication

➢Ultra-reliable Machine-Type Communication (uMTC) provides ultra reliable and lowlatency
communication for demanding applications.
➢ Two typical examples include road safety and traffic efficiency, and industrial manufacturing
which both have stringent requirements on low latency and very high reliability. In the road
safety and traffic efficiency applications, information is exchanged between traffic participants
using Vehicle-to-Vehicle (V2V), Vehicle-to-Pedestrian (V2P) or Vehicle-to-Infrastructure (V2I)
communication.
➢With a slight abuse of the terminology the term Vehicle-to Anything (V2X) includes V2V, V2P
and V2I, for traffic safety and efficiency applications. V2X communication includes both
periodic and event-driven messages. The periodic messages are transmitted to avoid the
occurrence of dangerous situations. A traffic participant can broadcast its position, velocity and
trajectory, etc. periodically (e.g. every 10 ms) to recipients within a certain range (e.g. 100 m).
➢The eventdriven messages are transmitted when an abnormal and/or dangerous situation is
detected, e.g. oncoming vehicles or accidents.
➢Though both kinds of messages should have high reliability, the event-driven messages are
more critical and should be received in the proximity with very high reliability and almost no
delay.
 Unit 3

Unit 2
How does the Network Function Virtualization ( NFV) framework work
• NFV aims at consolidating the variety of network equipment onto industry-standard high-
volume servers.
• These servers can be located at the different network nodes as well as end-user premises.
• In this context, NFV relies upon but differs from traditional server virtualization. Unlike server
virtualization, Virtualized Network Functions (VNF) may consist of one or more virtual machines
running different software and processes in order to replace custom hardware appliances
• As a rule, multiple VNFs are to be used in sequence in order to provide meaningful services to
the customer
• NFV requires an orchestration framework that enables proper instantiation, monitoring and
operation of VNFs and Network Functions (NFs) (e.g. modulation, coding, multiple access,
ciphering, etc.).
• In fact, the NFV framework consists of software implementations of network functions (VNF),
hardware (industry standard high volume servers) that is denoted as NFV Infrastructure (NFVI)
and a virtualization management and orchestration architectural framework.
• In order to realize real time requirements some NFV may need inclusion of hardware
accelerators.
• The accelerators take over computation intensive and time critical tasks that still cannot be
realized by NFVI.
• Hence, not only can traffic be offloaded from NFVI but also adherence of latency requirements
can be ensured.

Explain the Software Defined Networking (SDN) architecture of 5G?

 Unit 3

In a traditional network, each switch has its own control plane and data plane. Switches exchange
topology information to build a forwarding table that decides where to send data packets. In
Software-Defined Networking (SDN), the control plane is removed from switches and assigned
to a centralized SDN controller. This allows network administrators to manage traffic from a
single console instead of configuring each switch individually.
The data plane remains in the switch, forwarding packets based on flow tables set by the
controller. These tables contain match fields (like input port and packet header) and instructions
(forward, drop, or modify packets). If a packet doesn’t match any entry, the switch contacts the
controller, which provides a new flow entry to decide the packet’s path. A typical SDN
architecture consists of three layers.
 Application Layer: It contains the typical network applications like intrusion
detection, firewall, and load balancing.
 Control Layer: It consists of the SDN controller which acts as the brain of the network.
It also allows hardware abstraction to the applications written on top of it.
 Infrastructure Layer: This consists of physical switches which form the data plane and
carries out the actual movement of data packets.
The layers communicate via a set of interfaces called the north-bound APIs(between the
application and control layer) and southbound APIs(between the control and infrastructure layer).
 Unit 3

What is Functional split criteria, Functional optimization for specific applications.

Functional split criteria,
• In particular, when it comes to functional split, the following aspects should be carefully taken
into account :
• Centralization benefits: Defining whether the architectural approach would imply benefits in
case it is centralized with respect to the case of distributed implementation
• Computational needs and diversity: Some functions may require high computation capabilities
that should be provided centrally, at the same time at these locations applications with very
different types of traffic demands may be implemented.
• Physical constraints on the link: With particular reference to the latency and bandwidth
requirements on the connections between central unit pool and remote units.
• Dependencies between different NFs in terms of synchronicity and latency toward the air
interface: NFs running at higher network layers in the OSI model are considered to be
asynchronous. Two NFs should not be split if one of them depends on time-critical information of
the other
Functional optimization for specific applications
• Functionality that may be optimized based on the scenario can be identified on all RAN
protocol layers.
• On physical layer, coding plays an important role, e.g. block codes for mMTC and turbo codes
for xMBB, hard-decision decoding for resource limited nodes, carrier modulation, e.g. single-
carrier for latency-critical applications and multicarrier for high-throughput services, or channel
estimation, which may be performed differently depending on the scenario
• On MAC layer, among others Hybrid ARQ may be differently optimized depending on latency
requirements, mobility functions highly depend on the actual user mobility, scheduling
implementations must take into account user density, mobility, and QoS requirements and random
access coordination may be optimized for MTC if necessary.
 Unit 3

Explain an Interleave division multiple access (IDMA ) system with block diagram
• IDMA aims at improving the performance of Code Division Multiple Access (CDMA) systems
in asynchronous communications .A turbo type multiuser detector is proposed which includes the
simplest receiver, denoted as Elementary Signal Estimator (ESE) or soft rake detector , consisting
of a soft demodulator delivering an equivalent performance as the much more complex linear
receiver for asynchronous users. A basic block diagram is shown in Figure.
• Similar to CDMA, IDMA applies some kind of spreading to the signal by applying a low-rate
channel code, depicted in the figure as “FEC encoder”.
• The main difference with CDMA is that the channel code may not contain a repetition code and
may be the same for all users, while the distinction of the users is enabled by different
interleavers ∏k; which are anyway usually part of the system to decouple coding and modulation.
The spreading can be done either in time or in frequency domain, where frequency domain may
be preferred if a multicarrier waveform or a combination with FDMA or OFDMA is assumed
• IDMA is especially suited for the UL including unscheduled communication, as it is robust to
asynchronicity and suboptimal rate and power allocation due to the use of iterative receivers
instead of SIC. D. Due to the spreading in frequency domain, frequency diversity can be
exploited even without frequency-selective scheduling. As a special case, IDMA can be similar to
NOMA if appropriate rate and power allocation is applied. In this case, the iterative receiver
degrades to a SIC receiver

Explain Orthogonal frequency division multiple-access systems in 5G with block diagram.

 Unit 3

 Orthogonal Frequency Division Multiple Access (OFDMA) is a key multiple-access

technique used in 5G New Radio (NR). It is an enhancement of Orthogonal Frequency
Division Multiplexing (OFDM), allowing multiple users to simultaneously share the same
frequency resources efficiently.
 OFDM divides the available bandwidth into multiple orthogonal subcarriers to prevent
interference.
 OFDMA further improves this by assigning different subcarriers to different users,
making it highly efficient, flexible, and scalable for 5G networks.
Block Diagram of an OFDMA System
Transmitter Side:
 Data Input: User data is divided into multiple parallel streams.
 Modulation: Data is modulated using QPSK, 16-QAM, or 64-QAM.
 Subcarrier Mapping: The modulated symbols are mapped to specific subcarriers for
different users.
 Inverse Fast Fourier Transform (IFFT): Converts frequency domain signals into the
time domain for transmission.
 Cyclic Prefix (CP) Addition: Adds redundancy to prevent inter-symbol interference
(ISI).
 Parallel-to-Serial (P/S) Conversion: Converts parallel signals into a serial stream for
transmission.
 RF Transmission: The signal is transmitted over the wireless channel.

Receiver Side:
 RF Reception: The received signal is captured from the wireless channel.
 Serial-to-Parallel (S/P) Conversion: Converts serial data into parallel data streams.
 Cyclic Prefix Removal: Removes the CP to recover the original signal.
 Fast Fourier Transform (FFT): Converts the received time-domain signal back into the
frequency domain.
 Subcarrier Demapping: Extracts the assigned subcarriers for each user.
 Demodulation: Recovers the original data symbols from the modulated signals.
 Data Output: The final recovered data is delivered to the user

Applications of OFDMA in 5G
📶 Enhanced Mobile Broadband (eMBB): High-speed internet, 4K/8K video streaming.
🚗 Ultra-Reliable Low-Latency Communication (URLLC): Autonomous vehicles, industrial
automation.
🌎 Massive Machine-Type Communication (mMTC): IoT, smart cities, remote sensors.

Explain Filter-bank based multi-carrier (FBMC) system.

 Unit 3

Filter-Bank Based Multi-Carrier (FBMC) is an advanced multi-carrier modulation technique that

enhances traditional Orthogonal Frequency Division Multiplexing (OFDM) by reducing
spectral leakage and improving spectral efficiency.
Unlike OFDM, which uses a Cyclic Prefix (CP) to handle interference, FBMC employs filter
banks to shape individual subcarriers, providing better frequency localization and eliminating the
need for CP. This makes FBMC particularly useful for 5G, beyond 5G (B5G), and cognitive
radio applications.
Key Features of FBMC
✔ No Cyclic Prefix (CP): Reduces overhead and improves bandwidth efficiency.
✔ Better Spectral Efficiency: Reduces out-of-band emissions, allowing closer spectrum use.
✔ Enhanced Frequency Localization: Uses well-designed filters for each subcarrier,
minimizing interference.
✔ Higher Robustness to Channel Distortions: Performs better in fading and time-variant
channels.
✔ Supports Asynchronous Transmission: Allows flexible and dynamic resource allocation.
Applications of FBMC
🚀 5G and Beyond 5G Networks: Efficient spectrum usage for next-gen wireless
communication.
🌍 Cognitive Radio Networks: Helps in spectrum-sharing environments.
📡 Satellite and IoT Communications: Reduces interference and enhances connectivity.
🏭 Industrial Automation: Provides reliable communication for Industry 4.0.