There are a lot of anti gun device, like electronic dog, fixed speed, anti GPS anti GPS, multi band speed full band speed, full band two-way one-way anti anti speed GPS and so on. There are two key concepts, one is the two single and double band.
About the band: speed equipment in the world of the traffic police are used, there is a frequency, including fixed and mobile. Fixed speed devices generally refers to a fixed position, such as fixed installation, crossing the highway isolation belt on the frequency of these devices is fixed, so the electronic dog, the general anti single frequency speed GPS can be based on their frequency characteristics to effectively carry out the early warning, to remind the owners attention.
Multi band and single band, similar, just can be used for the determination of one or two fixed frequency speed measuring device.
However, in the speed measuring device installed at fixed locations, but not the owners are most worried about, because most of the owners can see these devices, and the corresponding reduction in order to avoid speeding. The most difficult is the flow speed measuring device, the flow velocity measuring device and measuring device is general traffic police handheld or mobile monitoring vehicle configuration, it is impossible to let owners. Moreover, the frequency of the measuring device of each region is not uniform, the self driving and driving the car owners to bring a lot of trouble a lot like.