Research On Uplink Interference Identification And Avoiding Methods Of TD-LTE System

By the end of August 2016, the number of 4G users has reached to 660 million. And the number is still increasing, so the study of 4G is of great significance. The identification and avoiding of interference of TD-LTE system is the key to ensuring the quality of network operations.In current network test, manual station check is usually adopted. However,considering the large number of base stations, it not only costs a lot of resource but also is low efficiency. Automatic interference identification will reduce the cost and improve the efficiency effectively.In this paper, waveform of 29 cities was analyzed in interference principle, frequency band and waveform. We analyzed the possible sources of interference from the appearance of interference waveforms.This paper improved the recognition algorithm of roll-off interference waveform in TD-LTE interference diagnosis system, and redesigned the recognition algorithm of high-class interference waveform. Then the interference pattern recognition of MMDS and jammer was proposed. It improved the accuracy of inter-system interference identification, and expanded the types of inter-system interference identification.Because different types of interference waveform have different interference sources, different verification schemes are designed for each type of interference waveform. To verify the recognition algorithm of roll-off interference waveform and the recognition algorithm of partial carrier waveform, the interference waveform of 682 interference cells in four representative cities were selected. Experimental result showed that the recognition algorithm proposed in this paper had a great improvement on both the combination of sensitivity and recall rate and recognition accuracy. To verify the recognition algorithm of MMDS and jammer type,the confirmed stations mixed with other stations. Experimental result showed that the recognition algorithm proposed in this paper can identify the type of interference effectively.At last, the module of TD-LTE interference diagnosis system was introduced, which aimed introducing the position of inter-system identificaition system. Then, the interference avoidance scheme was summarized. It was inctroduced from three aspects: F-band interference avoidance scheme, E-band interference avoidance scheme and D-band interference avoidance scheme.