Mutual Information-Based Power Allocation and Co-Design for Multicarrier Radar and Communication Systems in Coexistence

In this paper, exploring multicarrier waveforms, we investigate the performances of co-existence between radar and communication systems. Performances are measured in terms of radar mutual information (RMI) for the radar system and communication data rate (CDR) for the communication system. Two joint design schemes are proposed based on isolation and sharing, respectively. Firstly, for the isolation-based scheme, radar and communication signals are transmitted/received on the isolated bands. Two independent problems of RMI/CDR maximization are proposed and the optimal power allocation solutions can be characterized using Karush-Kuhn-Tucker (KKT) optimality conditions. This scheme undertakes the advantage of interference avoidance and easy implementation. Secondly, for the sharing-based scheme, radar and communication signals can be transmitted/received on the same band and the RMI/CDR maximization problems are jointly solved. The optimal power allocation solutions are optimized by the proposed sequential optimization algorithm. Compared with the isolation-based scheme, this scheme is more flexible and brings additional gain on performance at the price of higher complexity. Finally, simulation results are provided to analyze and discuss the performance and validate the theoretical results.