Comprehensive Report: Cellular Signals Jamming System Project Analysis

This report presents a project on designing a low-cost, high-efficiency cellular signals jamming system, focusing on 2G and 3G technologies. The project aimed to create a jammer for use in environments like schools and educational institutions. The report covers the project background, objectives, and the student's role as team leader, managing workflow and technical aspects. It details the application of engineering knowledge, including FDMA and TDMA, and the use of RF amplifiers and antennas. The report also discusses challenges faced, such as RF signal generation issues, and the solutions implemented, like the use of RF power amplifiers. The project's successful outcome in disabling cell phone signals within a 1 km radius is highlighted, along with suggestions for future work on 4G networks. The report concludes with an overview of the student's contributions, emphasizing the application of circuit design and telecommunication engineering skills.

Competency
Demonstration Report
(CDR)
Career Episode 3

CE 3.1: Project Introduction
Name of the Project : Cellular Signals Jamming System in 2G And 3G
Geographical Location : [Please Fill]
Project Duration : [Please Fill]
Organization : [Please Fill]
Position in the Project : Team Leader
CE 3.2. Project Background
CE 3.2.1: Characteristics of the Project
With the sudden rise of technology applications, various areas including temple,
shopping malls, class rooms and restaurants have witnessed a rise for the use of mobile phones at
an extreme level. I have observed that the application of the mobile jamming system are used for
preventing the mobiles phone operations But, due to the development complexity and
operational cost, the mobile jammers are not widely used in commercial ways. Therefore, I
undertook this project for the design of low cost and high efficient mobile jammer that can be
widely used in schools and educational institute for reducing the mobile usage.
CE 3.2.2: Objectives developed for project
During my work in this project I have considered my significant aim to design an
effective and low cost jammer that can be used within a pre-specified area within few kilometers.
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Therefore, I have focused on the design of advanced jammers with the application of two radio
frequency amplifiers. Through the application of two amplifiers, I have aimed at increasing the
frequency range of jamming the mobile phones signals. Furthermore, during the design I have
aimed at providing a simple and low cost design of the jammer that can be used by
commercially. For the practical implementation in this project I have sub divided the total
domain of work in various objectives as discussed in the section below:
 To evaluate the various technology that can be used for jamming the mobile signals;
 To propose the appropriate design plan for the mobile jammer;
 To select the appropriate hardware components for design of the phone jammer;
 To develop the appropriate block diagram for the jammer;
 To implement the required system and conduct analysis for performance
measurement;
CE 3.2.3: My area of work
Being associated as the team leader, in this project, I had to manage the work flow and
technical work for the implementation of the jamming system. I have identified the working
principle and operational objectives for the design of the mobile phone jamming system. Apart
from that, I have worked for developing the required simulation environment for conducting the
analysis of the developed antenna jamming system.
CE 3.2.4: Project Group
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Figure 1: Team Member Associated with the Project
CE 3.2.5: My responsibilities throughout the project
In this project I had the entire responsibility of developing the appropriate technical plan
for integrating the mobile phone jamming system. I have allocated the work load equally among
the team members for ensuring timely completion of the design. Moreover, I have worked during
the selection of the technology and hardware system while developing the design for integrating
and blocking the mobile signals.
CE 3.3: Distinctive Activity
CE 3.3.1: Comprehending the Theory of the project
The criteria of the mobile jammer are to block the operation of the mobile phones with
the application of radio waves. The mobile jammer uses the same frequency of the mobile for
overriding the signals. In this project, the mobile jammer uses WCDMA 2100, PSC 1900, DCS
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1800 and GSM 900 for jamming the mobile frequencies. I have used the mobile jammer for
blocking the mobile signal through similar band width. I have used the generation of the RF
signals for jamming the mobile phones using GSM. The jamming devices provide the output of
the signal at one or more frequencies at provide input power. The output powers of the jammer
interfere with the ongoing communication between the mobile phone towers and cell phones.
The jammers developed in the project uses frequency disruption along the radius for disrupting
the operation within particular area.
CE 3.3.2: Engineering Knowledge and Skills applied in the project
I have used FDMA (Frequency Division Multiple Access) and TDMA (Time Division
Multiple Access) in the design of the required mobile jammer. For the FDMA channel, I have
divided the spectrum into 200 kHz and for TDMA I have divided the spectrum into 8 timeslot. I
have allocated 4.6 ms duration for each timeslot and integrated power supply, antenna, RF
section and IF section. I have utilized the IF signal for generating frequency intermediate signals
with hundred Kilohertz. On the other hand, I was able to generate the RF signals within the range
of GSM signals. I have further used antenna for transmitting RF signals. I have integrated the
antenna in such a way that both the downlink and uplink frequencies were transmitted through
the implemented antenna. In the IF section, I have used RF power amplifier, RF generator,
antenna and triangular wave generator. In order to produce the appropriate noise in the circuit, I
have added TLO72CP noise generator in the design. For operating the system in the reverse
mode, I have used the zener diode along with the triangle wave. In the design of the required
phone phone signal jammers, I have used power amplifier, Max 303 RF section, mixer colpitts
oscillators, 555 timer for IF section, and 230 V, 50 Hz power supply. In this project I have learnt
that VCO output produces unmodulated RF carrier in the generated noise signal. Therefore, I
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have mixed the signal with the noise signal for obtaining the required frequency for blocking the
mobile phone signals.
CE 3.3.3: Accomplishment and Task Performed
After the development of the required block diagram for the design of the mobile signal
jammer, I have involved myself with the physical design and integration of the required antenna.
I have integrated the varactor and inductor of the tan on the chip and external components for
bypassing the capacitors used in the design. I have further kept the input range for the tuning
voltage between +0.4V to +2.4V.
CE 3.3.4: Identified Issues and Their Solutions
Issue: During the generation of the RF signal, I have utilized the technology and concept
of Max2623. Through this I was able to generate the signal range between 885- 960MHz with
the application of Voltage Controlled Oscillator. I have further used 0- 4.8 V of input for the
triangular wave signal. I have observed that the frequency of the triangular wave was observed to
be 142 KHz. I have faced significant issue in the project when I have learned that the generation
of the RF signal did not ensured the communication disruption between the communicating
phones.
Solution: Further for the elimination of the issue, I have reviewed the developed
architecture and theories used in the jammer device. After analyzing the design of the proposed
system, I have learnt that RF signal amplification is required for enhancing the jammer power for
the mobile equipments. Therefore I have used RF Power Amplifier for the improvement of the
signal. In this project I have used Max2235 as the required power amplifier. Through this I was
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able to use the jammer in the frequency band of 900 MHz. after the integration of the Max2235, I
have observed the required output for the jammer was to be +32.5dBm.
CE 3.3.5: Plan for producing creative and innovative work
I have worked for providing optimum power supply in the project for obtaining
innovative and creative work. For this reason I have focused on matching the transmission
system with the antenna system. Therefore, for the implementation of the mobile jammer, I have
used monopole antennas with 1/4 wavelength and input impedance of 50 Ω for matching the
required impedance of the jammer system. Due to the onmi directional radiation pattern, I have
selected the monopole antenna and obtained the required frequency of GSM 900 and 3G 2100
MHz. I have further applied driving signal for transmitter for receiving the output signal between
the ground plan and the receiver.
CE 3.3.6: Collaborative work
I was allocated in the project as the team leader for developing the appropriate design and
criteria for the mobile jammer. I have arranges several meeting with the team members for
discussing about the plan for design and implementation of the mobile phone jamming system.
Moreover, I have assisted the team members for the proper technical design and process for
imtegrating all the hardware element and developing the testing environment for the mobile
jammer.
CE 3.4: Project Review
CE 3.4.1: Project Overview
The proposed and developed prototype model was successful in disabling the cell phones
signals within 1 km radii of the base station used during the experiment. Moreover, the system
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was successful in blocking the mobile phones with GSM and 3G connectivity. Further study
needs to be done for blocking the phone signals with 4G network.
CE 3.4.2: My contribution to work
I have thoroughly utilized my knowledge and skills about circuit design and
telecommunication engineering in this project for ensuring the appropriate standard for antenna
implementation. I have further guided the team members and provided technical solutions and
advise for appropriately designing the mobile jammer.
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