Free Sample
The Complete Handbook of GPS Jammers
A practical reference for professionals, businesses, and serious hobbyists on selecting, operating, and profiting from GPS jamming equipment
by Alumigogo Books
Chapter 1: Understanding GPS Jammers
A GPS jammer is a radio-frequency transmitter. That is the entire technical essence. It emits a noise signal centered on the frequencies that the Global Positioning System uses for its broadcasts from satellites. When a nearby GPS receiver attempts to acquire or track those satellite signals, the jammer's noise raises the noise floor beyond the point where the receiver can distinguish the legitimate satellite data. The receiver either loses its position fix, can no longer acquire one, or — with some modern receivers — begins reporting wildly inaccurate positions derived from corrupted data.
The term "GPS jammer" is a disservice. It implies something more exotic than what the hardware actually is. In most cases, the device is a simple oscillator, an amplifier, and an antenna. The output is broadband noise covering the L1 frequency band at 1575.42 MHz, and in more capable units, the L2 band at 1227.60 MHz and the L5 band at 1176.45 MHz. These are the three frequencies that GPS satellites transmit on. L1 carries the coarse acquisition code, which is what civilian receivers use. L2 is primarily military, though it is also used by dual-frequency civilian receivers for ionospheric correction. L5 is the modern civilian band, used by newer receivers and especially by aviation equipment.
The jammer is not transmitting a "jamming code" or a "signal override." It is just making noise. Think of it as a radio that has been tuned to a frequency that only transmits static. The static