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Integrated sensing and communication has been identified as an enabling technology for forthcoming wireless networks. In an effort to achieve an improved performance trade-off between multiuser communications and radar sensing, this paper considers a dynamically-partitioned antenna array architecture for monostatic ISAC systems, in which each element of the array at the base station can function as either a transmit or receive antenna. To fully exploit the available spatial degrees of freedom for both communication and sensing functions, we jointly design the partitioning of the array between transmit and receive antennas together with the transmit beamforming in order to minimize the direction-of-arrival (DOA) estimation error, while satisfying constraints on the communication signal-to-interference-plusnoise ratio and the transmit power budget. An alternating algorithm based on Dinkelbach’s transform, the alternative direction method of multipliers, and majorization-minimization is developed to solve the resulting complicated optimization problem. To reduce the computational complexity, we also present a heuristic three-step strategy that optimizes the transmit beamforming after determining the antenna partitioning. Simulation results confirm the effectiveness of the proposed algorithms in significantly reducing the DOA estimation error.
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Power control and beamforming design for SWIPT in AF two-way relay networks
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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- Award ID(s):
- 1642865
- PAR ID:
- 10043845
- Date Published:
- Journal Name:
- IEEE International Conference on Communication Systems (ICCS), 2016
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Integrated sensing and communication has emerged as a transformative technology for future wireless communication networks, enabling the simultaneous realization of radar sensing and communication functions by sharing available resources. To fully exploit the available spatial degrees of freedom in monostatic ISAC systems, we propose a dynamic array partitioning architecture that allows the base station to allocate antennas for transmitting dual-functional signals and receiving the corresponding echoes. Based on this architecture, we jointly design the transmit beamforming and array partitioning to minimize the Cram´er-Rao bound (CRB) for target directionof- arrival estimation, while ensuring compliance with signalto- interference-plus-noise ratio requirements for multiuser communication, power budget constraints, and array partitioning limitations. To address the resulting optimization problem, we develop an alternating algorithm leveraging alternating direction method of multipliers and semi-definite relaxation. Simulation results demonstrate that the proposed joint array partitioning and beamforming design significantly improves the CRB and the resulting DOA estimation performance.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICCS.2016.7833632
