Study On Coexistence Interference Between LTE And WIFI In Mobile Termination

LTE and WIFI technologies have been widely used in the wirelesscommunication, however, the interference coexisting between the LTE and WIFI canno longer be ignored and research to find some ways to deal with this problem becomevery important.This paper principally studies the mutual interference coexisting between theBand7in FDD-LTE and WIFI and between the Band40in TDD-LTE and WIFI. Byanalyzing the cause of the interference, three ideas are summarized to optimize theinterference, including increasing antenna isolation, reducing interference oftransmitter and improving anti-interference of receiver. By designing a conductingexperiment to test the minimum antenna isolation without interference of coexistingbetween the LTE and WIFI systems, it shows that to completely avoid the mutualinterference is impossible, but only can be optimized. The adjacent channel leakageratio of LTE is optimized to reduce the transmitter interference, test results show thatthe adjacent channel leakage ratio is-39dBm and the current is maintained at below700mA when LTE Band7and LTE Band40work in21dBm with±10M bandwidth, tobetter meet the design requirements. By designing a coupling experiment to test thereceiver sensitivity, it comes to the optimizing way through contrasting the data beforeand after the changes of adding the band-pass filter in the transmitter and receiver RFcircuits.