Research On Multiple Antenna Transmission Technology Based On Spatial Modulation

With the rapid development of wireless communication technology, the high speed multimedia wireless demand is growing rapidly, how to utilize the limited communication resource to achieve a higher transmission rate and spectrum utilization will become the problem. Spatial modulation(SM) as a new MIMO technology in the data rate, noise reduction, cost reduction, etc has great advantage, but in the avoid using poor channel conditions, the receiver complexity, etc there are obvious defects. So in order to guarantee the performance of th e spatial modulation system, satisfy the needs of the development of mobile communication, study the new antenna selection algorithm and receiving algorithm is particularly important.This paper studies existing antenna selection algorithm, to eliminate the poor channel conditions influence, is presented PEP antenna selection algorithm based on pair error probability. Because of the BER is only related to the maximum pair error probability, the algorithm looks for all possible combination of transmitting antenna. Because the algorithm is a kind of traversal method, computational complexity is high, so we propose an improved antenna selection algorithm, the original PEP algorithm is decomposed into two situations to reduce the complexity. The results show that the proposed antenna selection algorithm has an improved ber performance than the original systemFor the problem of high complexity of SM receiver, we propose a low complexity of detection algorithm based on Geometric Decoding. Differs from that of the optimal ML, this algorithm will be transmitting antenna number of detection and modulation symbols of separatily, first to test the antenna number, then use Geometric Decoding to reduce the search space of modulation symbols detection. The simulation results show that compared with ML, the proposed algorithm has the same BER, while effectively reduce the complexity of the receiver.Considering the actual situation of perfect channel state information cannot be obtained in the receiving end, the iterative channel estimation algorithm based on least squares estimation is used. This algorithm uses pilot signal to get initial channel matrix, and use the detection result and receiving signal to estimate the channel to get more accurate channel estimation.Simulation results show that the PEP algorithm improve the BER compared to the original system, while the low-complexity detection algorithm reduces the complexity while remain almost the same BER compared with ML detection.