See discussions, stats, and author profiles for this publication at: https://www.researchgate.

net/publication/336471493

Hidden Active Cell Phone Detector

Article · January 2017

CITATIONS READS
0 3,692

5 authors, including:

Raj Kumar Mistri

Iiit ranchi
22 PUBLICATIONS   14 CITATIONS   

SEE PROFILE

Some of the authors of this publication are also working on these related projects:

synthesis of antenna array using artificial intelligence View project

All content following this page was uploaded by Raj Kumar Mistri on 12 October 2019.

The user has requested enhancement of the downloaded file.

IJSART - Volume 3 Issue 5 – MAY 2017 ISSN [ONLINE]: 2395-1052

Hidden Active Cell Phone Detector

Rajkumar Mistri1, Goutam Mahto2, Babita Kumari3, Kritika Keshriyar4, Dhiraj Kumar5
Department of ECE
1, 2
Assistant Professor,RTCIT Ranchi, India
3, 4, 5
B.Tech Scholar,RTCIT Ranchi, India

Abstract-As increase in the technology in the world using the microphones, internet, 802.11 wireless, and memory cards are
electronic equipment are being used in a wrong way like, in added every year. Also, the communication technology a
the examination halls and confidential rooms. To avoid this cellular phone uses such as CDMA, GSM, 3G and 4G are
we are introducing a project called hidden active cell phone rapidly changing.
detector. This handy, pocket size mobile transmission detector
or sniffer can sense the presence of an activated mobile cell B. Concept
phone from a distance of one and a half meters. So it can be
used to prevent use of mobile phones in examination halls, When a GSM (Global System of Mobile
confidential rooms, etc. It is also useful for detecting the use of Communication) digital phone is transmitting, the signal is
mobile phone for spying and unauthorized video transmission. time shared with seven other users. That is at any one second,
The circuit can detect the incoming and outgoing calls, SMS each of the eight users on the same frequency is allotted 1/8 of
and video transmission even if the mobile phone is kept in the the time and signal is reconstituted by the receiver to form the
silent mode. The moment the Bug detects RF transmission speech. Peak power output of a mobile phone corresponds to 2
signal from an activated mobile phone, it starts sounding a big watts with an average of 250 mW of continuous power. Each
alarm and the LED blinks. The alarm continues until the handset with in a ‘cell’ is allotted a particular frequency for its
signal transmission cases. Assemble the circuit on a general use. The mobile phones transmits short signals at regular
purpose PCB as compact as possible and enclose in a small intervals to register its availability to nearest base station. The
box. network data base stores the information transmitted by the
mobile phone. If the mobile phone moves from one cell to
Keywords-Intelligent detector, GSM signal, Cell phone, another, it will keep the connection with the base station
restricted areas having strongest transmission. Mobile phone always tries to
make connection with the available base station. That is why,
I. INTRODUCTION the back light of the phone turns on intermittently while
travelling. This will cause severe battery drain. So in long
In recent years, there has been increasing focus on journeys, battery will flat within a few hours. AM Radio uses
issues relating to the use of mobile phones in restricted, frequencies between 180 KHz and 1.6 MHz, FM Radio uses
prohibited, and unauthorized areas. The reason for this 88 to 180 MHz, TV uses 470 to 854 MHz Waves at higher
increased interest in largely due to disturbance, as well as frequencies but within the RF region is called Micro Waves.
wrong and inappropriate uses of mobile phones by the owners Mobile phones uses high frequency RF wave in the
and users alike. Other areas like churches, offices, and prisons, microwave region carrying huge amount electromagnetic
just to mention a few, are not left out. There is need for the energy. Thai is why burning sensation develops in the year if
detection of mobile phone signals in areas like these. Efforts the mobile is used for long periods. Just like a microwave
have been in place in tackling this issue but they all have their oven, mobile phone is cooking the tissues in the ear. RF
own shortcomings. Mobile phone uses RF with a wavelength radiation from the phone causes oscillation of polar molecules
of 3.3 to 10 cm at ranges from 0.9 to 3 GHz that is, the signal like water in the tissues. This generates heat through friction
is high frequency with huge energy. When the mobile phone is just like the principle of microwave oven. The strongest
active, it transmits the signal in the form of sine wave which radiation from the mobile phone is about 2 Watts which can
passes through the space. The encoded audio or video signal make connection with a base station located 2 to 3 Km away.
contains electromagnetic radiation which is picked up by the
receiver in the base station. II. PROPOSED DESIGN

A. Cellular Phone Technology Our proposed model consists of four parts i.e., the
capturing RF transmission stage, the current to voltage
Cellular phone technology is changing rapidly. converter, the trigger stage and the timer stage. The capturing
Features like Bluetooth, USB, high resolution cameras, stage consists an antenna can captures all frequencies in the

Page | 631 www.ijsart.com

IJSART - Volume 3 Issue 5 – MAY 2017 ISSN [ONLINE]: 2395-1052

mobile communication spectrum from 0.9 to 3 GHz. The the trigger input falls below the trigger level , the flip-flop is
transmission stage consists of a 0.22µF disk capacitor which set , and the output goes high If the trigger input is above the
receives the RF signal from the mobile phones. The current to threshold level , the flip-flop is reset and output is low . The
voltage converting stage consists of IC3130 which converts reset input can override all other inputs and can be used to
the current received from the previous stage into the initiate a new timing cycle . When rest goes low , the flip-flop
corresponding output voltage. The trigger stage transistors the is reset and the output goes low when the output is low , a low
timer from one state to another state(i.e., from stable to quasi impedance path is provided between discharge and ground .
stable state). The timer stage is responsible for period of
sounding the buzzer Table2: Pin Details of NE555
PIN PIN DESCRIPTION
A. IC DESCRIPTION NO.
1 Ground
CA3130: CA3130 is op-amp that combine the 2 Trigger
advantage of both CMOS and bipolar transistors .Gate – 3 Output
protected P channel MOSFET (PMOS) transistors are used in 4 Reset
the input circuit to provide very high input impedance , very 5 Control voltage
low input current and exceptional speed performance .The use
6 Threshold
of PMOS transistors in the input stage results in common
mode input voltage capability down to 0.5v below the 7 Discharge
negative supply terminal ,an important attribute in single 8 Power supply
supply applications .A CMOS transistor pair capable of
swinging the output voltage within 10mv of either supply BC548: This is general purpose silicon, NPN, BJT. It is used
voltage terminal , is employed as the output circuit. The for amplification and switching purposes. The current gain
CA3130 series circuits operate at supply voltages ranging may vary between 110 and 800. The maximum current gain is
from 5v to 16v . They can be phase compensated with a single 800. BC548 is used in common Emitter configuration for
external capacitor ,and have terminals for adjustment of offset amplifiers.
voltage for applications requiring offset – null capability .
III. CIRCUIT DESCRIPTION AND WORKING
Table1: Pin Details of CA3130
PIN NO. PIN DESCRIPTION The transmission frequency of mobile phones ranges
from 0.9 to 3 GHz with a wavelength of 3.3 to 10 cm. so, a
1 Offset Null
circuit detecting gigahertz signals is required for a mobile bug.
2 Inverting Input
Here the circuit uses a 0.22µF disk capacitor (C3) to capture
3 Non- inverting input the RF signals from the mobile phone. The lead length of the
4 V- capacitor is fixed as 18mm with a spacing of 8 mm between
5 Offset Null the leads to get the desired frequency. The disk capacitor
6 Output along with the leads acts as a small gigahertz loop antenna to
7 V+ collect the RF signals from the mobile phones. This system
8 NC comprises the capturing RF transmission stage, the current to
voltage converter, the trigger stage, timer stage. The capturing
NE555: The NE 555 operates over a range of (0-70) degree C stage consists antenna can captures all frequencies in the
.The important features of the 555 timer are :it operates from a mobile communication spectrum from 0.9 to 3 GHz. This
wide range of power supplies(+5V to +18V).These devices are transmission stage uses a 0.22µF disk capacitor , this capacitor
precision timing circuits capable of producing accurate time (C3) connected between the inverting and non-inverting inputs
delay or oscillation . In the time delay or mono-stable mode of of the op-amp. This capacitor stores energy and transfers the
operation , the timed interval is controlled by a single external stored energy in the form of minute current to the input of the
resistors and capacitors network . In the astable mode of current to voltage converting stage.
operation , the frequency and duty cycle can be controlled
independently with two external resistors and a single
capacitor. The threshold and trigger levels normally are two -
thirds and one - third , respectively , of VCC . These levels
can be altered by use of the control voltage terminal . When

Page | 632 www.ijsart.com

IJSART - Volume 3 Issue 5 – MAY 2017 ISSN [ONLINE]: 2395-1052

Fig .1 Circuit Diagram

The current to voltage converting stage converts the Fig.2 PCB Layout
minute current from the previous stage into the corresponding
output voltage by using a current to voltage converter Fig 3 represents artwork layout structure of PCB
operational amplifier (CA3130). Capacitor C4 along with
high-value resistor R1 keeps the non-inverting input stable for
easy swing of the output to high state. R2 provides the
discharge path for capacitor C4. Feedback resistor R3 makes
the inverting input high when the output becomes high.
Capacitor C5 is connected across ‘strobe’ (pin 8) and ‘null’
inputs (pin 1) of IC1 for phase compensation and gain control
the frequency response. When the cell phone detector signal is
detected by C3, the output of IC1 becomes high and low
alternately according to the frequency of the signal as
indicated by LED. The output of the IC1 will activate the
transistor Q1 and hence LED will glow. This also triggers
monostable timer IC2 through capacitor C7. When the
monostable timer IC2 is triggered, this will sound the buzzer.
Capacitor C6 maintains the base bias of the transistor Q1.
Fig.3 Artwork Layout of PCB
IV.PCB PREPARATION FOR PROPOSED MODULE
V. APPLICATIONS
Fig 2 represents the PCB Layout of our proposed
module. This has been developed in the Circuit Wizard There are several use of this proposed system. Some
Software. of which are (a) To avoid fault or any type of cheating in
examination halls. (b) To avoid accidents at petrol pumps. (c)
to avoid miscommunication in conference hall. (d) to avoid
video transmission in a secret or private meeting. (e) can be
used in military and civil defence for security purpose (f) can
be to maintain silence in religious places like temple , church ,
etc.

VI. CONCLUSION AND FUTURE SCOPE

This project is very useful for the private meetings ,

examination hall , defense establishment , military camps ,
petrol pumps, etc ., where the use of an active mobile
communication devices are prohibited . With the aid of this
system one can detect the active mobile phone device like
Page | 633 www.ijsart.com
IJSART - Volume 3 Issue 5 – MAY 2017 ISSN [ONLINE]: 2395-1052

objects and GPS systems from the range of few centimeters to

few inches depending upon the objects transmission strength
and other useful parameters . This device can detect objects
within a radius of 1.5 meters of radius and operating in the
frequency range of 0.9 to 3.3GHz .The system has no way of
discriminating between two phones within the same frequency
range .Therefore it is expected that future research will look
into this area .
REFERENCES

[1] D.Roy Choudhury and Shail B.Jain“linear Integrated

Circuit”,4th Edition,2012,PP-37-40&207-209
[2] J.B.Gupta“Electronic Devices and Circuits”,5th
Edition,August2012,PP-610-611&487-488
[3] http://projectsstrore.com
[4] www.phonejammer.com/home.php

Page | 634 www.ijsart.com

View publication stats