Time-Varying Doppler Frequency Offset Estimation Method for LTE-TDD Uplink with Multi-user in HST Scenario

摘要

A time-varying Doppler frequency offset estimation method is proposed for the high-speed-train travelling over 350 km/h ground speed in the long term evolution-time division duplex (LTE-TDD) uplink with the multi-user. Based on the separated pilot symbols of each user, the single pilot symbol in one subframe is firstly segmented into halves to enlarge the estimation range, and then the cross correlation of the two pilot symbols in one subframe is employed to improve the estimation accuracy. To further improve the estimation accuracy, the autoregressive model is used to track the variation of the Doppler frequency offsets between the subframes. Simulation results show that the performance of the proposed method is much better than those of the available methods for the LTE-TDD uplink with the high-speed mobile multi-user, and it has a low computational complexity.