Types of 5G signal jammers, filter configuration?
In order to ensure the leading level of the 5G network, the 2.6GHz frequency band is preferentially selected for the 100MHz networking scheme design, which coincides with the operating frequency of the deployed TD-LTE system software in the D1/D2 frequency band. In areas where TD-LTE has not been cleared in the D1/D2 frequency band, 5G will encounter serious LTE co-channel interference technical problems. In addition, according to the summary of 5G jammer technology examples, 5G in the 2.6GHz frequency band will also encounter the interference technology of multi-channel microwave heating distribution system software (MMDS) of the broadcasting network, the interference technology of the wireless network transmission of the video surveillance system, and the interference technology of the pseudo base station. Jamming technology and jammer jamming technology, etc. Therefore, researching and identifying 5G interference problems is of great practical significance to promote 5G interference technology to solve problems, ensure customer experience and business process cognition.
1. LTE co-channel interference
In areas where TD-LTE in the D1/D2 frequency band has not been cleared, under long-term load conditions in TD-LTE residential quarters, terminal equipment will cause rising co-frequency interference in the same covered 5G residential quarters, which seriously affects the characteristics of 5G Internet. The intensity of LTE co-channel interference is closely related to factors such as the size of the co-covered area, the network environment, and the freight volume of LTE neighbors.
The main feature of LTE co-channel interference is that the 163-273 PRB noise floor used in the D1/D2 frequency band in the time domain increases significantly, and the waveform characteristics show characteristics related to the relative height of the production scheduling optimization algorithm; in the frequency domain, the 24h interference immunity The compressive strength fluctuates significantly with the freight volume and the trend analysis is basically consistent, showing significant uncertainty in the frequency domain. The typical waveform characteristics of LTE co-channel interference are shown in Figure 1 below.
2. MMDS interference
Multi-channel microwave heating distribution system software (MMDS) uses microwave heating working frequency to send at one point and receive at more points, and transmit TV, sound broadcast programs and data signals to the front of each cable digital TV public antenna TV system software or immediately Microwave heating system software distributed to individual customers. According to the configuration of MMDS transmission and transmission of TV programs in my country, MMDS operating in the 2500-2700MHz frequency range will cause serious interference to the 5G system deployed in the 2.6GHz frequency band. The interference characteristics are several regular continuous 8MHz networks. The bandwidth rectangular frame interferes with the technical waveform, as shown in Figure 2 below.
Figure 2 Typical waveform of MMDS interference
See Table 1 for MMDS transmission and distribution of TV programs in the 2500-2700MHz frequency band. It can be seen that the MMDS TV programs falling within 2515-2615MHz include the second half of channel 2 (4MHz network bandwidth), channels 3-14, etc. When the characteristics of the wave pattern of the residential area produce several regular continuous 8MHz bandwidth rectangular wave patterns, you can refer to Table 1 to analyze and determine and check the position of the broadcasting tower on the station.
3. Video surveillance system interference technology
Video surveillance system interference technology mainly refers to the interference of video surveillance system bridges and wireless network transmission facilities on the 5G platform, which belongs to illegal frequency band occupation interference. Today, residential quarters, houses and elevator safety and security monitoring equipment (commonly used in the 2.4GHz frequency band) are widely used, but the working frequency of the relevant equipment is not standard, and the illegal occupation of the 5G frequency band causes interference to 5G. At present, it has been found that the wireless video surveillance equipment of some manufacturers interferes with 5G. The interference characteristics are mostly broadband network interference, and the interference strength is relatively high, mainly concentrated in the range of 2515-2575MHz. In addition, the wireless network transmission equipment of the video surveillance system is mostly installed in hidden places such as elevator cars and roofs. It is difficult to check the interference. It is necessary to mainly check the areas where the video surveillance system is installed. The types of video surveillance system interference techniques are shown in Figure 3 below.
Figure 3: Wave pattern characteristics of video surveillance system interference technology
4. Pseudo base station interference
The pseudo-base station in the D frequency band will cause interference to the surrounding 5G residential area according to the same PCI and frequency band extension as the 4G network. The typical waveform characteristics of pseudo base station interference are shown in Figure 4 below.
Figure 4 The characteristics of the interference wave pattern of the pseudo base station
5. Jammer interference
The jammer blocks the communication between the communication base station and the terminal equipment according to the interference technology data signal with high transmission power in the whole frequency band. It is mainly installed and applied in schools, examination places and other areas. The time-domain typical interference technology characteristic of 5G residential area jammer interference with large network bandwidth is the rise of the noise floor of the whole frequency band or the rise of the noise floor of the large broadband network in the second half. The typical waveform characteristics of jammer interference are shown in Figure 5 below.
Figure 5 Characteristics of Jammer Interference Waveform
So with so much interference, how to improve? How to configure matching filters? Comments and discussions are warmly welcome.
