According to media reports, the satellite jammers not only interfere with satellite television signals, but also cause serious damage to national defense communications and normal civilian radio communications.
In addition, many Internet users fear that the radiation from jammers could harm the human body. The radio management service is still concerned about these illegal activities. However, online research easily found many providers of jammers. Judging from the public reports at various locations, virtually all of the jammers that can be found are installed by cable TV operators at various locations.
The official interpretation from one place is that "township cable TV operators have used jammers to interfere with the way individuals receive satellite TV signals in order to develop more viewers, so that masses cannot watch satellite TV normally, thus forcing them to become cable. users. "
The ground satellite wifi jammer can be divided into digital television picture signal interference and carrier (or narrowband) signal interference from the interference means. The first is to use illegal image interference, i.e. use the same digital form as the normal broadcast signal to make the normal image appear tiled or black. The interference is dominated by the occupation of the power, that is, the high power co-frequency signals are transmitted in the same direction, and the receiving channel of the satellite is occupied in a certain frequency range, so that the field strength of the interference signal is much greater than the field strength of the signal from the normal satellite reaching the ground. The purpose of suppressing the reception of the satellite signal. The latter is divided into interference in the same channel and interference not in the same channel.
For interference in the same channel, the interference signal may cause a mosaic or pause in the picture, and a black screen appears when the interference is severe. For non-co-channel interference, due to the frequency selection effect of the satellite receiver, the interference level may be higher than the signal level, but the interference level is so large that the tuner enters a saturated state and the TV screen will appear black at this time. However, satellite signal jammers are limited by distance and azimuth. Because the propagation loss of the transmitted interference microwave is related to the working frequency and the propagation distance, under the free space propagation condition, the longer the distance, the greater the interference capacity is bad.