Special analysis on mobile base station interference
Today, as mobile communications are transitioning from the second generation to the third generation, new technologies are constantly being applied and new mobile networks are constantly being built, which makes radio frequency resources increasingly scarce. Various potential interference sources are also being generated at an alarming rate. The existence of these interferences has a great impact on the operation of mobile networks. As a core issue of network optimization, solving the interference problem becomes increasingly important.
We use a network performance indicator to measure interference from mobile base stations, namely IOI (IOI-Interference on idle), which monitors the interference on idle channels to ensure ideal
Network performance), the IOI of a single time slot is >5 or the IOI of a single transceiver (RTF) is >40, indicating that there is interference in the cell.
High IOI situations can be divided into two categories: one is that the IOI of a single transceiver (RTF) is high; the other is that the IOI of the entire community is high.
If the problem only occurs on a single transceiver, the customer can switch the RTF
Observe to determine whether it is a hardware problem or a data problem. If after the switch, the IOI is high and follows the carrier frequency, you can replace the carrier frequency, duplexer and other hardware. If after the switch, the IOI is high.
Following RTF, you can modify frequency points and redo RTF data processing. 2. If the problem occurs in all or multiple transceivers in the community, then this situation is more serious than
It is more complex and requires detailed analysis of specific issues. Reasons and solutions for high IOI in the entire community:
1. The components on the receiving path fail or are not installed or used correctly: SUFR board, backplane, connecting cables, etc. Replace the boards and cables. In addition
It should be noted that the second-generation SURF2 board does not have a filter on the 0a/1a/2a terminals, only the B side. The antenna feed cannot be directly connected to these ports.
It can only be connected to side B, otherwise it will cause high IOI. 2. PB or BER anomalies will cause high IOI. Follow the procedures for handling PB and BER, and perform maintenance on the base station.
Perform commissioning, power balancing, and check the antenna standing wave ratio.
3. If there are abnormalities in the external repeaters, tower amplifiers, indoor distribution and other equipment in the community, it will cause high IOI. Please debug the external equipment and replace the equipment if necessary.
4. Antenna problems cause high IOI in the cell. You can determine whether it is an antenna problem by swapping the cell antennas and replace the antenna.
5. Interference from the external environment Some communication equipment may transmit at the same frequency as our GSM receiver, such as conference jammers. The best way to troubleshoot interference is to use a spectrum analyzer to scan the frequency to find the source of interference.