Investigation On MIMO Detection And Its Application In LTE-A System

With the rapid development of mobile communications and the combine with broadband wireless access technology, the demand of broadband mobile communications is becoming increasingly urgent. Therefore, in order to satisfy the requirements of high data rate, broad-bandwidth, low delay and high-speed mobility for the next-generation wireless communication systems,3GPP proposed LTE (Long Term Evolution) and LTE-A (Long Term Evolution-Advanced) technology supported by the major companies. Accordingly, research on the key technologies of LTE has attached considerable significance.This thesis focuses on the investigation of the detecting algorithm of MIMO (Multiple Input-Multiple Output) for LTE system. First of all, the commonly used traditional detecting algorithms of MIMO system are researched and analyzed. On the basis of those, some search detecting algorithms, such as GA (Genetic Algorithm) detecting algorithm, QRD-M, are researched. The simulation results are analyzed combined with the computational complexity, which shows that QRD-M algorithm can achieve a good trade-off between the complexity and performance. Afterwards, in order to make a further study on the application of QRD-M in real system, a link-level platform of LTE-A Uplink system is modeled, based on which, QRD-M algorithm is researched and a series of block error rate (BLER) and throughput curves are obtained. Finally, a detecting scheme which can improve the system performance is proposed, that is, at low SNR, the traditional linear MMSE detection is used while at high SNR, SQRD-M is provided, which can effectively improve the system throughput.