Analysis And Design For MIMO And Cooperative Wireless Communication System

In order to resolve the contradiction between wireless communication service requirements and limited wireless resources brought by the incessant growth in the number of mobile phone users in the whole world and the rapid increase in high rate and wideband wireless business volume, and mitigating wireless channel impairment, enhancing communication reliability and increasing transmission rate, Multiple-input multiple-output (MIMO) and cooperative communication technology become hotspot in wireless communication realm at present. MIMO technology takes full advantage of space resources, achieves multiple-transmit multiple-receive using muti-antennas and results in that channel capcity and spectral efficiency are doubled, while not increasing frequency spectrum resources and antenna transmit power; multiple communication links between the source node and the destination node are established in cooperative communication technology with a virtual multiple-input and multiple-output (MIMO) system formed at the same time, providing a new technique for MIMO implementation of small and mobile terminals.In this dissertation, we thorough study on MIMO communication system and cooperative communication system. The thesis begins with a summary of efforts poured into the topic by both domestic and international researchers and study on MIMO channel capacity, system performances, diversity performances in terms of cooperative relay network and cross-layer design respectively. Main results are listed as:1. Investigation is made upon MIMO channels capacity with co-channel interference and transmit spatial correlation over rayleigh fading channels. It is assumed that perfect channel state information (CSI) is available to the receive, but the transmitter has mot any CSI. exact closed-form expression of the moment generating function (MGF) of mutual information of MIMO channels and exact expression of the MIMO ergodic capacity are derived depending on multivariate statistics knowledge, especially the theory of matrix vairate distributions.2. Investigation is made upon STBC system based on transmit diversity. The trapezia method based on numerical integration for approximate performance analysis of orthogonal space-time block code (OSTBC) over Rician-Nakagami fading channels is adopted, and the approximate performance expressions are given. Good effect of trapezia approximate method is be validated by the simulation contrast of approximate curves and exact curves. The lesser segments for trapezia method could satisfy demand in practice, therefore approximate expressions could be significant to lower complexity of performance analysis and simulation.3. Investigation is made upon Optimum combining (OC) system based on receive diversity. The more universal case where the powers of co-channel interferers and noise are unequal is analyzed. The exact characteristic function of OC output signal to interference-plus-noise ratio (SINR) is derived by hypergeometric functions. The expression is written mainly in form of a determinant, and element on the expression could be denoted by integral.4. Investigation is made upon the diversity performance of wireless cooperative amplify-and-forward (AF) relay networks with SNR-Thresholds and hard decision detections. For twoi-hop cooperation scenario, end-to-end BER and outage probability are derived, and diversity analysis of wireless cooperative networks is presented. Then diversity analysis is generalized to multi-hop cooperation scenario where multiple thresholds are needed for each relay link. Theoretics analysis and simulation results show that as the SNR increases, the performance of the proposed SNR threshold-based scheme closely approaches the performance of the scheme that makes use of the CSI of all source-relay links.5. For Characteristics and request of decode-and-forward (DF) wireless cooperative sensor networks, Practical Cross-Layer Design scheme is proposed by the combination of equal gain combining (EGC) at physical and automatic repeat request (ARQ) at data link layer, and is analyzed further. It is shown by simulation that the EGC-ARQ Scheme of retransmission by both source and relays is better by comparing with EGC-ARQ Scheme of retransmission by only relays and EGC without ARQ.Those research achievements serve as theoretical tools for further researches and designs of wireless MIMO and cooperative communication technology, and are of profound theoretical significance and practical application value.