Table of Contents

Why there is 5G interference

According to the equipment composition of the satellite receiving system, the equipment used at this stage (the commonly used C-band LNB working frequency band is 3400MHz-4200MHz) and the frequency range used by the 5G base station (3400MHz-3600MHz);

At the same time, according to ITU-RS.2199-0 report, it is said that when the total power of the interference signal received by the satellite earth station exceeds -60dBm, the low noise variable frequency amplifier (LNB) will produce saturated interference.

The impact of 5G interference

In the process of my country’s 5G base station network deployment, if there is a C-band satellite ground station in the network, the C-band satellite ground station will be affected by the 5G base station interference. The phenomenon is that all the signals in the 3400MH7-4200MH7 frequency shares of all C-wave shares will be affected to varying degrees. If the effect is slight, the overall signal-to-noise ratio will decrease and the bit error rate will increase. If the impact is serious, the entire LNB is saturated and cannot work normally, and no L-band signal is output to the lower-level equipment.

How to solve the 5G interference

After a joint experiment by the relevant scientific research units of the State Administration of Radio, Film and Television and telecom operators, it was concluded that the installation of C-band filters can effectively avoid the interference of 5G base stations to C-band ground stations.

How the filter works

The principle of C-band filter is to efficiently pass microwave signals within the bandwidth of 3700MHz-4400MHz, while filtering microwave signals in the frequency range below 3700MHz and above 4400Hz. Therefore, the signal transmitted by the radio and television program through the satellite can be smoothly down-converted and amplified by the LNB and then output to the lower-level equipment for use.