In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from...In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from the existing works, the proposed algorithm is energy-efficient which is more applicable to the future green network. It considers both the sum-MSE problem and the power consumption problem for the users under the relay power constraint. Based on the optimal condition decomposition(OCD) method, the energy-efficient precoders at the users can be designed separately with limited information exchanged. The proposed relay beamforming algorithm is based on the alternative direction method of multipliers(ADMM) which has simpler iterative solution and enjoys good convergence. Simulation results demonstrate the performance of the proposed algorithms in terms of power consumption and MSE performance.展开更多
Codebook-based multiple input multiple output(MIMO) beamforming can significantly improve the system spectral efficiency with limited feedback and gets widely adopted.However,this scheme has a drawback of heavy feedba...Codebook-based multiple input multiple output(MIMO) beamforming can significantly improve the system spectral efficiency with limited feedback and gets widely adopted.However,this scheme has a drawback of heavy feedback load that the sum feedback rate can be a bottleneck for the communication system,especially when the number of users is large.In this paper,a new scheme using pseudo-random beamforming vectors and angle based threshold in the feedback process is proposed.In the proposed scheme,both the base-station and the users have no need to store a codebook.In each access procedure,the base-station generates a pseudo-random beamforming vector,and each user calculates the angle between the beamforming vectors and its channel state information(CSI) vector.If the angle is less than a predefined angle-threshold,the user feeds back its channel quality indicators(CQI),otherwise it keep silence.Compared with the codebook based scheme,the proposed scheme can largely reduce the sum feedback rate with negligible throughput loss.In particular,when the system has a constraint on the total sum feedback rate in uplink channel,the proposed scheme can increase the system throughput significantly.展开更多
基金supported by China National S&T Major Project 2013ZX03003002-003National Natural Science Foundation of China under Grant No. 61176027, No.61421001111 Project of China under Grant B14010
文摘In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from the existing works, the proposed algorithm is energy-efficient which is more applicable to the future green network. It considers both the sum-MSE problem and the power consumption problem for the users under the relay power constraint. Based on the optimal condition decomposition(OCD) method, the energy-efficient precoders at the users can be designed separately with limited information exchanged. The proposed relay beamforming algorithm is based on the alternative direction method of multipliers(ADMM) which has simpler iterative solution and enjoys good convergence. Simulation results demonstrate the performance of the proposed algorithms in terms of power consumption and MSE performance.
文摘Codebook-based multiple input multiple output(MIMO) beamforming can significantly improve the system spectral efficiency with limited feedback and gets widely adopted.However,this scheme has a drawback of heavy feedback load that the sum feedback rate can be a bottleneck for the communication system,especially when the number of users is large.In this paper,a new scheme using pseudo-random beamforming vectors and angle based threshold in the feedback process is proposed.In the proposed scheme,both the base-station and the users have no need to store a codebook.In each access procedure,the base-station generates a pseudo-random beamforming vector,and each user calculates the angle between the beamforming vectors and its channel state information(CSI) vector.If the angle is less than a predefined angle-threshold,the user feeds back its channel quality indicators(CQI),otherwise it keep silence.Compared with the codebook based scheme,the proposed scheme can largely reduce the sum feedback rate with negligible throughput loss.In particular,when the system has a constraint on the total sum feedback rate in uplink channel,the proposed scheme can increase the system throughput significantly.