Research Of Channel Estimation Technique In TD-LTE-Advanced System

In this paper, firstly, we introduced the brief history of mobile communication from1G to4G and the understanding of5G, anylized the characteristics of wireless channel andthe parameters of the channel model of LTE-Advanced, discussed the basic principles andthe mathmetic thought of OFDM and MIMO techniques.Channel estimation technique is one of the key techniques in receiving part ofwireless communication. Whether the transmitted data can be demodulated correctly isdirected influenced by this technique. Researching on channel estimation is significant.This paper starts with some classical channel estimation algorithms and interpolationalgorithms, and then researches on how the algorithms are used in TD-LTE-Advancedsystem. In the LTE-Advanced system, MU-MIMO is supported by the uplink. WhenMU-MIMO is used, the reference signals of different users are completely overlapped.This leads some difficulty to channel estimation. In this paper, we proposed an improvedDFT-based channel estimation algorithm which can separate the reference signals ofdifferent users taking notice of the properties of Zadoff-Chu sequences. Compared withDFT-based algorithm, this algorithm can have better performance since it can remove theinterference resulted from overlapping of reference signals, remove more noise anddecrease edge effect.Proposed algorithm is simulated in varity scenarios using TD-LTE-Advanced linklevel simulation platform built with matlab. Compared with other simulated algorithms, theMSE curve, BER curve and BLER curve of proposed algorithm is really good. Simulationsshowed that the performance of proposed algorithm is efficient.As it has almost the same complexity and better performance compared withDFT-based algorithm, the proposed algorithm can be one of the practical algorithms.