Constant Modulus Waveform Design for Integrated Sensing and Communication Systems

The constant modulus (CM) waveform design for integrated sensing and communication (ISAC) systems is a key technology. The joint design of maximizing the Signal-to-Interference-and-Noise-Ratio (SINR) for radar and minimizing the Multiple User Interference (MUI) for communication is studied. The problem is nonconvex and NP-hard, due to the fractional expression and the CM constraint. To address this issue, a low-complexity Accelerated Coordinate Descent (ACD) method is proposed. First, the problem is simplified to a quadratic function with CMC by dinkelbatchs method. Then, a CD method is derived, by transforming the problem into a decomposable problem with multiple one-dimensional subproblems. Finally, the ACD algorithm is derived to accelerate the convergence by using the square iterative technique. Simulation results show that the proposed method obtains favorable trade-off performance between SINR and MUI.