| The requirements raised by people inspire the development of wireless communication techniques. After finishing the research of the fourth generation mobile communication systems, some research projects for the fifth generation (5G) mobile communication systems, which will be applied in about 2020 year, have been launched at home and abroad. The basic objectives of 5G are to:increase the throughput of the current system by 1000-fold, improve the energy efficiency by 10-fold, shorten the end-to-end delay by 1/5-1/10, enlarge the number of connected equipment by 10-100 folds and prolong the battery lives of low-power equipment by 10-fold. There are three key techniques for 5G from the perspective of system capacity:firstly, massive-antenna technique is adopted to improve the system spectrum efficiency; secondly, millimeter wave spectrum resources are employed to expand the system bandwidth; thirdly, the multi-layer and denser networks are deployed to increase the geographic spectrum reusability. The systems employing massive-antenna arrays are called massive-antenna communication systems. Massive-antenna system not only can compensate the severe fading of millimeter wave signals, but also can realize the wireless backhaul and suppress the interference in multi-layer and denser networks. Therefore, this paper studies the performance of massive-antenna communication systems in order to provide the theory for the design of practical systems.The first chapter of this paper introduces the emergence meaning, the basic concept and the main research topics for massive-antenna technique; then we present the state-of-the-art of the related research at home and broad, including the channel measurements and modeling, physical layer and networking layer techniques. Analysis indicates:firstly, the basic performance of massive-antenna communication systems is absent, such as the theoretical outage probability and bit error rate at the user; secondly, some emerging metrics, which are paid more attention by communication filed in recent years, are little studied for massive-antenna communication systems, such as the energy efficiency considering the circuit power consumption and the performance of hybrid energy and information transfer; thirdly, the current researches focus mainly on single-cell and homogeneous multi-cell scenarios, less on the new application scenarios, such as the massive-antenna relay communication systems. Therefore, this thesis studies the performance of the massive-antenna communication system in consideration of the above aspects.The second chapter studies the spectrum efficiency and reliability for downlink massive-antenna communication systems in single-cell scenario. Under perfect channel state information (CSI) assumption and with the finite number of antennas, the single-to-interference-plus-noise ratio (SINR) and the probability density functions of the variables in the SINR are given when the base station employs either the maximum ratio transmission (MRT) or zero-forcing (ZF) precoder. Based on the SINR and the variable distributions, the tight lower bound of spectrum efficiency is then derived, the asymptotic and optimal values of spectrum efficiency are analyzed and compared between the two precoders in detail. Finally, the reliability,including the outage probability and non-coded bit error rate, is deduced for the two precoders according to the users’SINRs and the variable distributions in the SINRs.The third chapter studies the spectrum efficiency, energy efficiency and their relation of the uplink massive-antenna communication system in multi-cell scenario. The contents of this chapter are the supplement and echo to the contents of the downlink single-cell in the second chapter. When the base station employs either the maximum ratio combination or ZF detector, the users’SINRs and the probability density distributions of the variances in the SINR are given, based on which the tight lower bound of spectrum efficiency is derived and its characteristics are discussed. Then, the realistic power consumption model of the uplink system is established for both the users and base station, which consists of both the radiated power and circuit power. Based on the established model, the theoretical trade-off between the energy efficiency and spectrum efficiency is developed and is compared to the tradeoff considering only the radiated power. According to the tradeoff, the general expression of the optimal energy efficiency is derived, and the relation between the optimal energy efficiency (as well as the corresponding spectrum efficiency) and various system parameters, including the number of antennas at the base station, the number of multiplexed users, the system bandwidth and the cell radius, is analyzed.The fourth chapter studies the performance of hybrid energy and information transfer in the massive-antenna communication systems, which is an extension of the former chapters. Guaranteeing the rate requirements of information users and the fairness among energy users, we study the energy harvesting performance under MRT precoder. Firstly, the optimal combination coefficients of energy precoder and the energy harvesting performance are deduced under perfect CSI in single-cell scenario. When the matched filter is employed at the base station to estimate the CSI in single-cell scenario, the influences of both the orthogonal piloting scheme and the shared piloting scheme in the uplink are studied for the downlink energy transfer. The optimal pilot power allocation and the energy harvesting performance of the two schemes are given and compared. Finally, in contrast to the non-cooperative scheme, a cooperative power transfer scheme is studied in both centralized and distributed implements. The combination coefficients and the energy harvesting performance are derived for both implementations.The fifth chapter studies the spectrum efficiency and energy efficiency of the massive-antenna relay communication systems, which is a supplement to the scenarios of the former chapters. When the relay node employing the ZF filter serves multiple user-pairs in the same time-frequency resources, the power allocation of jointing the source nodes and relay node is studied in order to maximize the spectrum efficiency or energy efficiency. The SINRs and its properties of the destination nodes are firstly analyzed for both the amplify-and-forward and the decode-and-forward protocols. Then, the instantaneous and ergodic spectrum efficiency expressions are derived for both protocols. Based on the instantaneous and statistic CSIs, two types of water-filling power allocation schemes are developed in order to maximize the spectrum efficiency. Finally, a realistic power consumption model is established under the amplify-and-forward protocol. The relation between the energy efficiency and the power allocation of nodes is deduced. In order to achieve the optimal energy efficiency, two iterative power allocation algorithms are developed based on the instantaneous CSI and statistic CSI.
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