| The use of multiple antennas has emerged as a promising technique for achieving an ever higher data rate in the next generation wireless systems. The design of such a multi-antenna system is often determined by a comparative analysis among the available transceiver strategies. The main theme of this dissertation is to provide two such examples. One example is the use of multiple user methods in a Multiple-Input-Multiple-Output (MIMO) Broadcast Channel (BC) under partial Channel State Information (CSI) feedback constraint. The other is the practical transceiver structures in a point-to-point MIMO system for a Wireless Local Area Network (WLAN) system. In addition, this dissertation discusses the ordering problem that arises in a vectored Discrete Multi-Tone (DMT) system and proposes a simple theorem to find the best pre-coder ordering that maximizes the sum-rate.; The first example compares three transmission schemes for a Gaussian MIMO BC under a partial CSI feedback constraint. In a Gaussian MIMO BC, a simultaneous service of multiple users usually provides a larger sum rate. In some practical situations with a partial CSI feedback, however, this dissertation reveals that serving only one user at a time can be a better transmission strategy. This phenomenon is true until the number of users in the system is less than a certain threshold. This threshold varies as the other system parameters such as Signal-to-Noise-Ratio (SNR) or the number of transmit antennas changes.; The second example compares three advanced transceiver structures for the next generation WLAN system. A higher data rate is achieved by pre-coding the transmitted signal using Singular Value Decomposition (SVD) of the channel matrix, using a sphere-decoding type of soft bit calculation or a Successive Interference Cancellation (SIC) receiver. These options differ from one another in that they perform differently along with other system parameters and require different hardware modifications. |
