Explain the function of GPS jammer, how to use GPS jammer | #car gps jammer

It is difficult to define the number of jamming devices that exist, however if there is a frequency should therefore be a countermeasure that allow the jamming of a frequency. However the full spectrum of bands is very large and it is impossible that a jammer can jam itself all the frequencies, in fact cannot be and never will be broad-spectrum jammers that can block all bands. So the jammers use to target the most common communications bands. Since jamming devices have a very high cost of development, and this has led to the jamming devices have specialized in the most common frequencies. Within these bands (most common) are the following:
https://www.jammer-mart.com/
Cell phone jammer, which focus primarily on the GSM, GPRS, 2G, DCS, 3G and 4G frequencies recently. Those jammers have the function to block or override the audio communications and data transmission through the internet. Often used to avoid a security risk, and to prevent leakage and information theft also help prevent privacy risks, as there are phones that are used to hung the calls automatically to hear the conversations. These frequencies are also common GSM 3G spy or spy cameras and microphones currently 4G, so an inhibitor in these frequencies can deter and eliminate intrusions. Also interesting are the locations to avoid through signal triangulation, with which you can easily locate the telephone user. Also often used so widespread in universities and schools, to avoid the use of spy earpiece or headphones used to cheat on tests.