Research On Low Complexity Detection Method Based On Joint Reactive Tabu Search And Message Passing

Massive MIMO(Massive Multiple-input Multiple-output,Massive MIMO)is a natural extension of traditional MIMO technology.By expanding the number of antennas deployed at the base station to tens,hundreds or even thousands,the use of multiple antenna arrays in the transmitter and receiver can increase the capacity and spectrum efficiency of the network connection several times.While Massive MIMO brings advantages,it also causes a series of problems.As the number of antennas increaseing,the dimension of the channel gain matrix increases.Therefore,higher requirements are put forward for the signal detection algorithm at the base station.The goal is to achieve a low-complexity and high-performance detector.The Minimum Mean Square Error(MMSE)algorithm has better detection performance,but the matrix inversion process of this algorithm is highly complex in the case of multiple antennas.The thesis improves the traditional MMSE algorithm and proposes a MMSE algorithm based on iterative inversion of blocks.First,it is proved that the MMSE filter matrix in the Massive MIMO system is real symmetric and positive definite,and the characteristics of channel hardening are introduced at the same time.Then a real symmetric matrix block iterative inversion algorithm is used to replace the matrix inversion part in the process of MMSE signal detection.Finally,the detailed implementation process of the algorithm is described.Through the simulation results,we can see that the detection performance of the improved MMSE algorithm in this thesis is similar to that of MMSE detection,but has a lower algorithm complexity,which is conducive to engineering realization.Aiming at the problem of poor performance of Reactive Tabu Search(RTS)signal detection algorithm under high-order modulation,the thesis proposes a joint Reactive Tabu Search-Message Passing Detection(RTS-MPD)algorithm.After the input signal is output by the RTS algorithm,the interference cancellation operation is performed,and then the interference cancellation signal is used with the Message Passing Detection(MPD)algorithm to reduce the probability of error in the last bit of the output symbol.Finally,through experimental simulation and debugging,the performance of the given RTS-MPD joint algorithm is analyzed.