CDMA Cellular Phone Jammer EE413 – Communication Electronics Instructor: Pao-Lo Liu TA: Saurav K. Bandyopadhyay Michael D. Kaprow Justin R. Antes Adam J. Pace JAM TECH ® Version 2005 All Rights Reserved

Presentation Outline Goals of Project Description and Analysis of Circuit Demonstration of Circuit Accomplishments Questions EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Project Goals To create a device that will disrupt cellular communication with respect to the following: - Operate in the 1900 MHz band. - Disallow any communication of phones that use that band. (Denial of Service) - Have a two meter effective blocking radius. JAM TECH ® Version 2005 All Rights Reserved EE 413 Communication Electronics Spring 05’

Circuit Description JAM TECH ® Version 2005 All Rights Reserve EE 413 Communication Electronics Spring 05’

TL074 Quad Op Amp EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Square Wave Generator Generates the signal that will be manipulated to control the VCO. EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Integrator -The Integrator takes the square wave and transforms it into triangular wave. - This triangular wave is what allows the VCO to sweep the band of CDMA frequencies. EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Buffer Buffer prevents the noise from interfering with the Square wave generator and Integrator. EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Noise Generator -Operate a Zener diode in reverse bias to create noise. -Amplified with 2N3904 transistor and the LM386 audio amplifier EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve -Noisy signal is what overloads the frequencies.

Mixer -The mixer is where the triangular wave and the nose get mixed. -The tuning circuit adjusts amplitude of wave and amount of noise being coupled to signal. EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve

Voltage Controlled Oscillator (VCO) - An oscillator designed so the output frequency can be changed by applying a voltage to its control port or tuning port - Crystek CVCO55BE

Actual Circuit EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve VCO Quad OpAmp LM386 Potentiometer

Demonstration JAM TECH ® Version 2005 All Rights Reserve

EE 413 Communication Electronics Spring 05’ JAM TECH ® Version 2005 All Rights Reserve Weeks Research and Development 1.1 research technology 1.2 Develop circuit diagram 1.3 Select and order Componets 2.0 Construct Project 2.1 Build Circuit 2.2 Evaluate Circuit 2.3 Debug Circuit 3.0 Prototype Design + Evaluate 3.1Test Final Build 3.2 Demo 3.3 Documentation

Possible Improvements We can add another VCO to block the 800MHz digital roam feature on some phones. (Verizon comes standard) We can also add amplifiers that can boost the area that is affected. JAM TECH ® Version 2005 All Rights Reserve

Accomplishments We were able to block communication coming into and going out from a CDMA phone operating on the 1900MHz frequency band. We were able to reach the 2 meter blocking radius. We were able to keep the cost under 50 dollars. JAM TECH ® Version 2005 All Rights Reserve

Questions JAM TECH ® Version 2005 All Rights Reserved