mobile jammer

Cell Phone Jammer
Abstract
The last few years have witnessed a dramatic boom in the wireless communications industry, hence increasing the number of users of mobile communication devices. This magnified the need for a more e client and reliable signal scrambler. This paper deals with the Mobile Jamming Technology. A mobile Jammer is an instrument which is used to prevent mobile phones from receiving signals from the base stations. This can be used in practically at any location, but are mostly found in places where a phone call would be particularly disruptive because silence is expected.
The concept of jamming technology is studied in a step-by-step approach. Those steps include Introduction to mobile jammer, Components of mobile jammer, Mobile jamming techniques, Design parameters for mobile jammer, Block diagram of mobile jammer and Legal issues related with mobile jammer along with the Alternatives of mobile jammer.

Introduction
Communication jamming devices were first developed and used by military. Where tactical commanders use RF communications to exercise control of their forces, an enemy has interest in those communications. This interest comes from the fundamental area of denying the successful transport of the information from the sender to the receiver.
Nowadays 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 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.
Mobile jammer is used to prevent mobile phones from receiving or transmitting signal with the base stations. Mobile jammer effectively disables mobile phone within the defined regulated zones without causing any interference to other communication means Mobile jammer can be used in practically any location, but are used in places where a phone call would be particularly disruptive like Temples, Libraries, and Hospitals Etc.
Mobile jammers were originally developed for law enforcement and the military to interrupt communications by criminals and terrorists to foil the use of certain remotely detonated explosives. The civilian applications were apparent with growing public resentment over usage of mobile phones in public areas on the rise & reckless invasion of privacy. Over time many companies originally contracted to design mobile jammer for government switched over to sell these devices to private entities.
As with other radio jamming, mobile jammer block mobile phone use by sending out radio waves along the same frequencies that mobile phones use. This causes enough interference with the communication between mobile phones and communicating towers to render the phones unusable. Upon activating mobile jammer, all mobile phones will indicate "NO NETWORK”. Incoming calls are blocked as if the mobile phone were off.

When the Mobile jammers are turned off, all mobile phones will automatically re-establish communications and provide full service. Mobile jammer’s effect can vary widely based on factors such as proximity to towers, indoor and outdoor settings, presence of buildings and landscape, even temperature and humidity play a role.
The choice of mobile jammers are based on the required range starting with the personal pocket mobile jammer that can be carried along with you to ensure undisrupted meeting with your client or a personal portable mobile jammer for your room or medium power mobile jammer or high power mobile jammer for your organization to very high power military jammers to jam a large campuses.

Why mobile jammer is needed?
It's great to be able to call anyone at anytime. Unfortunately, restaurants, movie theaters, concerts, shopping malls and churches all suffer from the spread of cell phones because not all cell-phone users know when to stop talking. Who hasn't seethed through one side of a conversation about an incredibly personal situation as the talker shares intimate details with his friend as well as everyone else in the area?? While most of us just grumble and move on, some people are actually going to extremes to retaliate. Cell phones are basically handheld two-way radios. And like any radio, the signal can be disrupted, or jammed.
A mobile Jammer is an instrument which is used to prevent mobile phones from receiving signals from the base stations. This can be used in practically at any location, but are mostly found in places where a phone call would be particularly disruptive because silence is expected.
How a GSM Jammer works
Cell phones communicate with a service network through cell towers. Cell towers are placed in specific places to provide service to small areas. As a cell phone is moved between these areas, the towers pass the signals. A GSM jammer transmits on the same airwaves that cell phones do. When the jammer is activated, it is able to disrupt the signal between the cell phone and the nearest tower. Because the GSM jammer and the cell phone use the same frequency, they effectively cancel the other signal.

History
The rapid proliferation of cell phones at the beginning of the 21st century to near ubiquitous status eventually raised problems such as their potential use to invade privacy or contribute to rampant and egregious academic cheating. In addition public backlash was growing against the intrusive disruption cell phones introduced in daily life. While older analog cell phones often suffered from chronically poor reception and could even be disconnected by simple interference such as high frequency noise, increasingly sophisticated digital phones have led to more elaborate counters. Cell phone jamming devices are an alternative to more expensive measures against cell phones, such as Faraday cages, which are mostly suitable as built in protection for structures. They were originally developed for law enforcement and the military to interrupt communications by criminals and terrorists. Some were also designed to foil the use of certain remotely detonated explosives. The civilian applications were apparent, so over time many companies originally contracted to design jammers for government use switched over to sell these devices to private entities. Since then, there has been a slow but steady increase in their purchase and use, especially in major metropolitan areas.
Older jammers sometimes were limited to working on phones using only analog or older digital mobile phone standards. Newer models such as the double and triple band jammers can block all widely used systems (AMPS, iDEN, GSM, et al) and are even very effective against newer phones which hop to different frequencies and systems when interfered with. As the dominant network technology and frequencies used for mobile phones vary worldwide, some work only in specific regions such as Europe or North America.
The power of the jammer's effect can vary widely based on factors such as proximity to towers, indoor and outdoor settings, presence of buildings and landscape, even temperature and humidity play a role.
There are concerns that crudely designed jammers may disrupt the functioning of medical devices such as pacemakers. However, like cell phones, most of the devices in common use operate at low enough power output (