Channel Estimation and Demodulation for MIMO-OFDM System Under Fractional Timing Offset

Abstract

For the channel offset caused by the time offset(TO) of the MIMO-OFDM system, we propose a new high-precision and low complexity new channel estimation algorithms, which is based on least squares(LS) method to solve the problem that we need to send a lot of pilot symbols to estimate the channel coefficient again when the fractional timing offset is present, which greatly reduces the complexity of the system. Meanwhile, we combine the new algorithm and Vectoring technology, so that it allows multiple transmitted signals through the down-link pre-coding matrix and the actual channel to each receiver, completely eliminating the multiple user interference caused by transmitted signals of multiple users and accurately extracting the signal of each user. Simulation experiments prove that the new algorithms have good estimation performance.