In this paper, we study optimal spatio-temporal power mask design to maximize mutual information (MI) for a joint communication and (radio) sensing (JCAS, a.k.a., radar-communication) multi-input multi-output (MIMO) downlink system. We consider a typical packet-based signal structure which includes training and data symbols. We first derive the conditional MI for both sensing and communication under correlated channels by considering the training overhead and channel estimation error (CEE). Then, we derive a lower bound for the CEE and optimize the energy arrangement between the training and data signals to minimize the CEE. Based on the optimal energy arrangement, we provide optimal spatio-temporal power mask design for three scenarios, including maximizing MI for communication only and for sensing only, and maximizing a weighted sum MI for both communication and sensing. Extensive simulations validate the effectiveness of the proposed designs.

中文翻译：

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具有训练开销的MIMO联合通信和无线电传感系统的时空功率优化

在本文中，我们研究了最佳时空功率掩模设计，以使联合通信和（无线电）传感（JCAS，又名雷达通信）多输入多输出（MIMO）下行链路系统的互信息（MI）最大化。我们考虑一种典型的基于分组的信号结构，其中包括训练和数据符号。我们首先考虑训练开销和信道估计误差（CEE），得出相关信道下的感知和通信条件MI。然后，我们得出CEE的下限，并优化训练信号和数据信号之间的能量安排以最小化CEE。基于最佳的能量安排，我们为三种情况提供了最佳的时空功率掩模设计，包括最大化仅用于通信和仅用于感知的MI，并最大化用于通信和感测的加权和MI。大量的仿真验证了所提出设计的有效性。