Radar Waveform Design under Communication Sum Capacity Constraint

Abstract

This paper considers a joint radar/wireless communication system where the radar transmit waveform is adaptively designed. To ensure co-existence environment of the radar and communication systems operating in the same frequency bands, the radar makes the best use of knowledge provided by the communication systems. Radar waveform is designed not only to maximize radar performance such as signal-to-interference-and-noise ratio (SINR) and mutual information (MI) but also to guarantee proper working of the communication systems. We formulate optimization problems that maximize the radar performance subject to the radar power constraint and the communication sum capacity constraint. Since the sum capacity constraint is not a convex constraint, the resulting optimization problem is not convex. We provide geometric analysis of the sum capacity constraint and solve the maximization problem in two steps: 1) obtain the optimal solution with only radar power constraints and then 2) starting from the optimal solution of the first step, iteratively find the optimal solution satisfying the sum capacity constraint. Numerical results are provided to verify the proposed method.