Methods for Mitigating Inter-carrier Interference Caused by Power Amplifier Transient in LTE Modem

Abstract

Power amplifier transient of LTE modem is discussed. In current LTE specification, the requirement of power amplifier transient period for LTE modem is within 40μs. Under this requirement, non-negligible inter-carrier interference (ICI) can be observed for both of normal cyclic prefix (CP) (=4.7μs) and extended CP (=16.7μs). We analyze the ICI in terms of the transient response of power amplifier and propose ICI mitigation schemes: 1) digital pre-distortion at transmitter 2) low complexity multi-tap equalization at receiver based on the ICI analysis.