In this paper, we study the problem of joint power control and beamforming design for simultaneous wireless information and power transfer (SWIPT) in an amplify-and-forward (AF) based two-way relaying (TWR) network. The considered system model consists of two source nodes and a relay node. Two single-antenna source nodes receive information and energy simultaneously via power splitting (PS) from the signals sent by a multi-antenna relay node. Our objective is to maximize the weighted sum energy at the two source nodes subject to quality of service (QoS) constraints and the transmit power constraints. However, the joint optimization of the relay beamforming matrix, the source transmit power and PS ratio is intractable. To find a closed-form solution of the formulated problem, we decouple the primal problem into two subproblems. In the first problem, we intend to optimize the beamforming vectors for given transmit powers and PS ratio. In the second subproblem, we optimize the remaining parameters with obtained beamformers. It is worth noting that although the corresponding subproblem are nonconvex, the optimal solution of each subproblem can be found by using certain techniques. The iterative optimization algorithm finally converges. Simulation results verify the effectiveness of the proposed joint design.
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Hybrid Precoding/Combining Design in mmWaveAmplify-and-Forward MIMO Relay Networks
In this paper, we consider the amplify-and-forward
relay networks in mmWave systems and propose a hybrid
precoder/combiner design approach. The phase-only RF precoding/
combining matrices are first designed to support multi-stream
transmission, where we compensate the phase for the eigenmodes
of the channel. Then, the baseband precoders/combiners are
performed to achieve the maximum mutual information. Based
on the data processing inequality for the mutual information,
we first jointly design the baseband source and relay nodes to
maximize the mutual information before the destination baseband
receiver. The proposed low-complexity iterative algorithm for
the source and relay nodes is based on the equivalence between
mutual information maximization and the weighted MMSE. After
we obtain the optimal precoder and combiner for the source
and relay nodes, we implement the MMSE-SIC filter at the
baseband receiver to keep the mutual information unchanged,
thus obtaining the optimal mutual information for the whole
relay system. Simulation results show that our algorithm achieves
better performance with lower complexity compared with other
algorithms in the literature.
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- Award ID(s):
- 1642536
- NSF-PAR ID:
- 10108975
- Date Published:
- Journal Name:
- IEEE International Conference on Communications
- ISSN:
- 1938-1883
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Conference Paper:
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