Robust transceiver designs for MIMO relay communication systems

The thesis investigates robust linear and non-linear transceiver design problems for wireless MIMO relay communication systems with the assumption that the partial information of the channel is available at the relay node. The joint source and relay optimization problems for MIMO relay systems are highly nonconvex, in general. We transform the problems into suitable forms which can be efficiently solved using standard convex optimization techniques. The proposed design schemes outperform the existing techniques

Joint Source and Relay Optimization for Multiuser MIMO Relay Communication Systems

In this paper, we design the source precoding matrices and the relay amplifying matrix of an amplify-andforward multiuser multiple-input multiple-output (MIMO) relay communication system. The minimum mean-squared error (MSE) is taken as the design criterion. We propose an alternating technique to efficiently solve the nonconvex source and relay optimization problem. It is shown that both the optimal source and relay matrices have a beamforming structure. Simulation results demonstrate that the proposed source and relay design algorithms perform much better than the existing techniques in terms of both MSE and bit-error-rate

Transceiver Design for Dual-Hop Non-regenerative MIMO-OFDM Relay Systems Under Channel Uncertainties

In this paper, linear transceiver design for dual-hop non-regenerative (amplify-and-forward (AF)) MIMO-OFDM systems under channel estimation errors is investigated. Second order moments of channel estimation errors in the two hops are first deduced. Then based on the Bayesian framework, joint design of linear forwarding matrix at the relay and equalizer at the destination under channel estimation errors is proposed to minimize the total mean-square-error (MSE) of the output signal at the destination. The optimal designs for both correlated and uncorrelated channel estimation errors are considered. The relationship with existing algorithms is also disclosed. Moreover, this design is extended to the joint design involving source precoder design. Simulation results show that the proposed design outperforms the design based on estimated channel state information only.Comment: 30 pages, 6 figures, IEEE Transactions on Signal Processing, The Final Versio

Joint Transceiver Optimization for Multiuser MIMO Relay Communication Systems

In this paper, we address the optimal source, relay, and receive matrices design for linear non-regenerative uplink multiuser multiple-input multiple-output (MIMO) relay communication systems. The minimum mean-squared error (MMSE) of the signal waveform estimation at the destination node is adopted as our design criterion. We develop two iterative methods to solve the highly nonconvex joint source, relay, and receiver optimization problem. In particular, we show that for given source precoding matrices, the optimal relay amplifying matrix diagonalizes the source-relay-destination channel. While for fixed relay matrix and source matrices of all other users, the source matrix of each user has a general beamforming structure. Simulation results demonstrate that the proposed iterative source and relay optimization algorithms perform much better than existing techniques in terms of both MSE and bit-error-rate