Classification of big antenna

Antenna polarization compass is divided into vertical polarization and circular polarization. With today's technology, vertical polarization effects than circular polarization. 　Except in special cases, the big antenna with circular polarization. 　• Place the compass on the antenna divided into internal and external antennas. The Assembly position of the antenna is also very important. Early handheld machines with eversion-type antennas, antenna and internal isolation, EMI almost does not affect collecting star works well. Now, with the miniaturization trend, the big antenna built-in. 　This antenna must be at the top all metal components, shell plating and well grounded, away from EMI interference sources, such as CPU,SDRAM,SD cards, Crystal, DC/DC. Vehicle navigation will be more and more common. And the shell of the car, especially car explosion-proof membrane Beidou signal serious obstacles. A magnet (can be adsorbed onto the roof) external antenna for car GPS/compass navigation is very necessary.