Research On MIMO Detection In TD-LTE Systems

This paper makes a research on the signal detection method for spatially multiplexed MIMO in TD-LTE downlink system receiver.First, the development of mobile communication technology is introduced, and then the basic idea of MIMO-OFDM technology and the characteristics of wireless channel model are analyzed. Then, it shows the model for spatially multiplexed MIMO-OFDM system and introduces several traditional signal detection algorithms for spatially multiplexed MIMO systems. Although maximum-likelihood decoding is the optimal detecting algorithm, its extremely high complexity excludes its application to practical MIMO system, especially when high-level modulation and large number transmit antenna is used. So considering the difficulties to keep the balance between performance and complexity in traditional signal detection algorithms in MIMO systems, several methods which achieve near-ML performance but require significantly less complexity than the optimal ML method are introduced, an signal detection algorithm is proposed according to the antenna number of TD-LTE downlink system, which require lower computational complexity than the optimal ML method in higher-level modulation especially. All the algorithms in this paper are simulated and compared in Matlab and the simulation results show that the proposed algorithm performs well for TD-LTE system. Finally, the soft-output technology in MIMO system is studied and simplified. A total solution to the signal detection module for different modulation scheme in TD-LTE downlink system is proposed and some suggestions about the enhancement of throughput and the frequency of working clock are made.