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GPS is through the receiving satellite signal, or the positioning navigation terminal. While receiving signalmust be used in antenna. GPS satellite signal is divided into L1 and L2, frequencies were 1575.42MHZ and 1228MHZ, where L1 is open civil signal, signal for circular polarization. Signal strength was about 166-DBM, which belongs to the weak signal. These characteristics decided to GPS signal receiving specially prepared antenna. Polarization of GPS antenna is divided into vertical polarization and circular polarization.With today's technology, vertical polarization effect than the circular polarization. Therefore, except in special cases, GPS will use the circular polarization antenna. The way from place GPS antenna for built-in antenna and external antenna. Antenna assembly position is also very important. Early GPS handset byeversion type antenna, the antenna and the internal base isolation, EMI almost does not affect the effect of good, collect stars. Now with the miniaturization trend, GPS with built-in antenna. The antenna must beabove all metal device, shell plating and must be well grounded, away from the EMI interference sources,such as CPU, SDRAM, SD card, crystal, DC/DC. Application of on-board GPS will become more and more popular. While the outer shell of the vehicle, in particular car explosion-proof membrane GPS signal to produce a serious obstacle. A strip magnet ( can be adsorbed onto the roof ) of the external antenna for car GPS is very necessary.

Editor this paragraph GPS antenna structure.

Most of the current GPS antenna is polarized dielectric ceramics, its components are: ceramic antenna, low noise signal module, cable, connector. Ceramic antenna which is also called passive antenna, dielectric antenna, PATCH, it is GPS antenna core technology. A GPS antenna signal receiving capability, mostlydepends on how the ceramic portion of ingredient composition. Low noise signal module, also known as LNA, is the signal amplifying and filtering part. The component selection is very important, otherwise it will increase the GPS signal reflection loss, as well as caused by excessive noise. Cable selection but also toreduce the reflection for the standard, ensure that the impedance matching.