Design And Construction Of An RF GSM Mobile Jammer

ABSTRACT

This work is on RF GSM mobile jammer. The main purpose of this Final Year Project is designing a mobile jammer that enables user to jam the mobile devices at undesired places such as meeting room, class room, library, and worship places. The mobile device can jam all the mobile devices nearby. Therefore, it is required to design a complete system which contents power system, IF section and RF section. Basically, this device operates at GSM frequencies which are GSM900 and GSM1800. GSM 900 is a designed for extensive radio coverage even in rural areas. DCS 1800 is designed for radio coverage in areas with very high subscriber density. Communication jamming device was first developed by military .the device was used for denying the successful transport of information from the sender (tactical commanders) to the receiver (army personal),and vice-versa. Nowadays, the mobile devices are becoming very important for our daily life. Here in Malaysia, there are three telecommunication companies such as Celcom, Maxis and Digi. All of these telecommunication companies are using dual band of frequencies such as GSM900 and GSM 1800. Even thought using of cell phone is every important for our daily life but these cell phone devices are creating some problems as the sound of ringing becomes annoying or disrupting in our environment. So the device jammer is the solution to avoid the annoying or disrupting of the cell phone devices. As I mentioned early, the device jammer consists of three sections which are power supply, IF section and RF section. The technology behind the jammer device is that, RF section transmits signals in frequency range which is quite similar to frequency range of cell phone device. These signals which are coming out from jammer device will interface cell phone signals which results in a no network available display on cell phone screen.

CHAPTER ONE

1.0                                                        INTRODUCTION

A wireless signal jammer is a device which blocks transmission by creating interference. This wireless signal jammer can be categorized into the Radio Frequency (RF) jammer and GSM jammer.

A Radio Frequency jammer is a device used to disrupt or prevent communication via a broadcasted RF signal. It is an RF and GSM frequency disrupter commonly known as wideband radio frequency (RF) and GSM cell phone jammer. Simultaneously, they can blocks all commercial FM broadcast band (87.5 MHz to 108 MHz) and GSM signal transmissions within the jammer’s transmission range. The device can possibly block these frequencies by transmitting a dirty signal (like noise) on the same frequency at which the GSM and radio system operates.

A Radio Frequency jammer is a device that transmits a radio frequency signal on the same frequency at which the radio system operates and the jamming succeeds when the radio sets in the area where the jammer is located are disabled.

A GSM jammer is a device that transmits a signal on the same frequency at which the GSM operates. The jamming succeeds when the mobile phones in the area where the jammer is located are disabled.

In recent times, where bombs are being planted and detonated by GSM or Radio Frequency signals, this device can be at an advantage by jamming the signals required for the detonation of the bomb.

Presently, the mobile jammer devices are becoming civilian products rather than electronic warfare devices, since with the increasing number of the mobile phone users the need to disable mobile phones in specific 2 places where the ringing of cell phone would be disruptive has increased. These places include worship places, university lecture rooms, libraries, concert halls, meeting rooms, and other places where silence is appreciated.

The solution to these annoying and disrupting noises is to install a device which can block the signal transmission from mobile phones and radio sets and thus, disrupt the triggering of bombs by these wireless signals.

1.2                                         BACKGROUND OF THE PROJECT

The technology being used by this device is very simple. The mobile phone transmission is being blocked and interfered by RF which creates high noise. The frequency being generated by the jamming device jams the signal being generated by the cell tower. When the signal has been blocked, the mobile phone will show “NO NETWORK” on the network bar, and radio devices will not be able to tune into any signal. Thus, all phones and radio devices in the 200m radius of the jammer will be having the same situation.

Radio Frequency (RF) and Mobile signal jammer is an illegal device in many countries. It is because the device is blocking the signal which has been approved by government agency as a legal communication transmission system. According to the National Communications Commission (NCC) in Nigeria, “The manufacture, importation, sale, or offer for sale, of devices designed to block or jam wireless transmission is prohibited”.

The reason I am developing this device is for educational purpose only. This device was developed and tested in this report just for Final Year Project presentation. There is no intention of manufacturing or selling such device in Nigeria or elsewhere. In the construction of this wireless signal jammer, the device will be able to jam GSM and Radio Frequency (RF) signals and this can be done alternatively through a switch.

1.3                                                  PROBLEM STATEMENT

Due to the increasing sophistication and high technology, most people are using mobile phones, and also due to the need for man to stay updated with his environment, the use of radio is also in wide use.

Mobile phones have become a very important communication tool today. With the use of the mobile phones everywhere, it becomes annoying device while working, studying, praying and many more.

Modern technology has contributed to the sophistication of bombs which are being triggered by GSM and Radio signals.

Wireless mobile jammer can be placed in schools, mosque, and conference hall, meeting rooms, library and many more places which need quiet and peaceful environment. This device will block the transmission of Radio and GSM signals.

1.4                                            OBJECTIVES OF THE PROJECT

The Development of Wireless Signal Jammer for Security Application objective is:

• To design Radio Frequency (RF), Intermediate Frequency (IF), and Power Supply circuit. To construct the Development of Wireless Signal Jammer for Security Application’s circuit.
• To construct the development of wireless signal jammer for security application’s circuit.
• To simulate Intermediate Frequency (IF) section circuit.
• To block mobile phones transmission by creating interference.
• To block amplitude modulated and frequency modulated signal transmission by creating interference within its range.

 1.5                                           LIMITATION OF THE PROJECT

This project only focuses on blocking the signal transmission of GSM900 which is the range between 935 to 960 MHz. This is because the components are hard to find in Nigeria for the GSM1800 frequency range between 1805 to 1880 MHz The components for GSM1800 are also very expensive compared to GSM900.

The second limitations of the project are, the device only can block the three main operators which are ETISALAT, MTN and GLOBACOM. This is because, the lines are only for Nigerian users and the frequency band range is between 935 to 960 MHz. These requirements fulfil the GSM900 specifications.

The third limitation is that for reliability of the jammer, a Radio Frequency amplifier should be incorporated but the components required for this are difficult to find in Nigeria.

1.5                                                                    APPLICATIONS OF JAMMER

Normally jammers are used in government offices in some countries, but jammers are mainly used by military, navy, air force and entire defense systems. People will not use jammers everywhere, but they use in selected places and highly confidential meetings, gathering etc.