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Electronically speaking,cell phone jammer are very basic devices. The simplest just have an on/off switch and a light that indicates it's on. More complex devices have switches to activate jamming at different frequencies. Components of a jammer include:
Antenna
Every jamming device has an antenna to send the signal. Some are contained within an electrical cabinet. On stronger devices, antennas are external to provide longer range and may be tuned for individual frequencies.
Circuitry
The main electronic components of a jammer are:
Voltage controlled oscillator - Generates the radio signal that will interfere with the cell phone signal
Tuning circuit - Controls the frequency at which the jammer broadcasts its signal by sending a particular voltage to the oscillator
Noise generator - Produces random electronic output in a specified frequency range to jam the cell-phone network signal (part of the tuning circuit)
RF amplification (gain stage) - Boosts the power of the radio frequency output to high enough levels to jam a signal
Power supply
Smaller jamming devices are battery operated.Some look like cell phone and use cell-phone batteries.Stronger devices can be plugged into a standard outlet or wired into a vehicle's electrical system.
Check your phone - If the battery on your phone is okay, and you'd like to continue your conversation, try walking away from the area.You may be able to get out of the GPS jammers range with just a few steps.
Jamming devices overpower the cell phone by transmitting a signal on the same frequency and at a high enough power that the two signals collide and cancel each other out. Cell phones are designed to add power if they experience low-level interference, so the cell phone jammer must recognize and match the power increase from the phone.
Cell phones are full-duplex devices, which means they use two separate frequencies, one for talking and one for listening simultaneously. Some jammers block only one of the frequencies used by cell phones, which has the effect of blocking both. The phone is tricked into thinking there is no service because it can receive only one of the frequencies.
Less complex devices block only one group of frequencies, while sophisticated jammers can block several types of networks at once to head off dual-mode or tri-mode phones that automatically switch among different network types to find an open signal. Some of the high-end devices block all frequencies at once, and others can be tuned to specific frequencies.
To jam a cell phone, all you need is a device that broadcasts on the correct frequencies. Although different cellular systems process signals differently, all cell-phone networks use radio signals that can be interrupted. GSM, used in digital cellular and PCS-based systems, operates in the 900-MHz and 1800-MHz bands in Europe and Asia and in the 1900-MHz (sometimes referred to as 1.9-GHz) band in the United States. Jammers can broadcast on any frequency and are effective against AMPS, CDMA, TDMA, GSM, PCS, DCS, iDEN and Nextel systems. Old-fashioned analog cell phones and today's digital devices are equally susceptible to jamming.
The actual range of the jammer depends on its power and the local environment, which may include hills or walls of a building that block the jamming signal. Low-powered GPS jammers block calls in a range of about 30 feet (9 m). Higher-powered units create a cell-free zone as large as a football field. Units used by law enforcement can shut down service up to 1 mile (1.6 km) from the device.
Cell phones are everywhere these days. According to the Cellular Telecommunications and Internet Association, almost 195 million people in the United States had cell-phone service in October 2005. And cell phones are even more ubiquitous in Europe.
Unfortunately, restaurants, movie theaters, concerts, shopping malls and churches all suffer from the spread of cell phone jammer 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.
Disrupting a cell phone is the same as jamming any other type of radio communication. A cell phone works by communicating with its service network through a cell tower or base station. Cell towers divide a city into small areas, or cells. As a cell-phone user drives down the street, the signal is handed from tower to tower.
A jamming device transmits on the same radio frequencies as the cell phone, disrupting the communication between the phone and the cell-phone base station in the tower.
It's a called a denial-of-service attack. The GPS jammers denies service of the radio spectrum to the cell-phone users within range of the jamming device.
Global Positioning System, also known as GPS, is defined as a satellite-based worldwide navigation system that gives out dependable location and time data in all types of weather anytime, anywhere on Earth. This satellite system has been kept by the United States government, wherein everyone can have free access to it when they have GPS receivers. It was created by the U.S. Department of Defense as an effective navigation solution for civilian and military purposes. Since its creation, it became a popular application for smart phone users to provide them guidance on their current location for safety and emergency purposes.
Through reading this article, you’ll end up being surprised why the title of this article is the need for British people to use signal jammer device, because the traffic and vehicle crimes committed in Britain have involved the use of such devices, and the information regarding their use is useful for British authorities to create countermeasures, such as jammer detectors, to help them capture criminals.
Due to the system’s reliable navigation feature, GPS systems have been installed on cars in developed countries, especially Great Britain. This navigation tool is very useful for new drivers to guide them while they drive to their desired destinations. A GPS system can also aid drivers to seek detours away from paths with heavy traffic.
Despite the system’s benefits, why do British people need a car GPS jammer? Usually, that device has been used by car robbers all over Britain to snatch luxury automobiles and lorries that contain valuable cargo without being detected through satellite by the British authorities. For frequent traffic violators, a gps tracking jammer is a useful tool to help them break traffic laws and become hidden from pursuing British law enforcement authorities.
The GPS jammers work by interrupting the signals that come from the satellite and make it impossible for a device to operate.GPS jammers are being created mainly for military organizations, gadget companies and the government organizations.
Mostly, commercial, military entities, and individuals utilize it for the navigational purposes. But before we begin to explain review the global positioning system, we need to fully understand what a GPS is portable jammer.
GPS utilizes the satellite system and sends signals. The satellite works with GPS receivers to find out positioning through triangulation. Triangulation is basically a technique and method in which three different points are being considered for computing location. For instance, in cars navigation, the location is being evaluated by three definite satellites revolving the earth. By means of triangulation, global positioning system can deliver the site to the recipient.
GPS signals make use of a definite and specific frequency. GPS works at two main frequencies. The one is intended for non-military or public use at 1575.42 MHz and the other one is meant for military purpose at 1227.6 MHz. Actually, GPS is based on radio waves.
Overall, using the GPS can be very useful, such as car navigation, finding missing persons and navigating in the sea. Even so, there are many different ways to misuse the GPS, and that is why we have the GPS jammers.
The GPS jammers work by interrupting the signals that come from the satellite and make it impossible for a device to operate. GPS jammers are being created mainly for military organizations, gadget companies and the government organizations.