In the sixth-generation (6G) networks, massive low-power devices are expected to sense environment and deliver tremendous data. To enhance the radio resource efficiency, the integrated sensing and communication (ISAC) technique exploits the sensing and communication functionalities of signals, while the simultaneous wireless information and power transfer (SWIPT) techniques utilizes the same signals as the carriers for both information and power delivery. The further combination of ISAC and SWIPT leads to the advanced technology namely integrated sensing, communication, and power transfer (ISCPT). In this paper, a multi-user multiple-input multiple-output (MIMO) ISCPT system is considered, where a base station equipped with multiple antennas transmits messages to multiple information receivers (IRs), transfers power to multiple energy receivers (ERs), and senses a target simultaneously. The sensing target can be regarded as a point or an extended surface. When the locations of IRs and ERs are separated, the MIMO beamforming designs are optimized to improve the sensing performance while meeting the communication and power transfer requirements. The resultant non-convex optimization problems are solved based on a series of techniques including Schur complement transformation and rank reduction. Moreover, when the IRs and ERs are co-located, the power splitting factors are jointly optimized together with the beamformers to balance the performance of communication and power transfer. To better understand the performance of ISCPT, the target positioning problem is further investigated. Simulations are conducted to verify the effectiveness of our proposed designs, which also reveal a performance tradeoff among sensing, communication, and power transfer.

翻译：在第六代（6G）网络中，大量低功耗设备预计将感知环境并传输海量数据。为提升无线资源效率，集成感知与通信（ISAC）技术利用信号的感知与通信功能，而同步无线信息与能量传输（SWIPT）技术将同一信号作为信息与能量传递的载体。进一步融合ISAC与SWIPT形成先进技术，即集成感知、通信与能量传输（ISCPT）。本文考虑一种多用户多输入多输出（MIMO）ISCPT系统，其中配备多天线的基站同时向多个信息接收机（IR）发送消息、向多个能量接收机（ER）传输能量，并对目标进行感知。感知目标可视为点目标或扩展表面。当IR与ER位置分离时，优化MIMO波束赋形设计以在满足通信与能量传输需求的同时提升感知性能。所得非凸优化问题通过舒尔补变换与秩缩减等一系列技术求解。此外，当IR与ER共址时，联合优化功率分配因子与波束赋形器，以平衡通信与能量传输性能。为深入理解ISCPT性能，进一步研究了目标定位问题。仿真验证了所提设计方案的有效性，并揭示了感知、通信与能量传输之间的性能权衡关系。