Design and Testing of a Mobile-Phone-Jammer

Dissimilar cellular-systems process signals differently, and yet, all cell-phone-networks use radio-signals that can be interrupted or, even, blocked, completely. This project highlights the design of a simple, low-cost mobile-phone-jammer and aims to present a solution for the problem of inappropriate-use of the cell-phones in restricted and prohibited-areas. The main concept of jamming is the releasing of signal (noise) of the same-frequency which is using by mobile-service-provider to overpower and destruct the user-signal. The fabrication of the jammer involved uncomplicated discrete components, resistors, capacitors, inductors and transistors to generate the required frequency ( noise ) and then amplifies the frequency generated to range of 800 MHZ to 1.4 GHZ in order to match the frequency of the mobile-phone being transmitted by the base-station. Relatively-satisfactory-jamming of a mobile-signal was confirmed by the blocking of the signals of the mobile-phones in 2G and 3G-networks (UMTS / WCDMA) operated via Safaricom, Airtell, Orange, and YU service-providers, when the phone indicated “ no network ”, thereby allowing no call to go through, with no-interference to other communication-means observed. Overall recommendation is that further and more deeper-research is needed to produce more-sophisticated and better jamming devices, as not to affect the other base-station-transmission-systems. Keywords: mobile, phone, jammer, design, signal.