Efficient Algorithms for Designing Sparse Linear Arrays With Desired Beampattern for Dual-Function Radar and Communication Systems

In this article, we address the problem of designing a sparse transmit array with a defined beampattern for applications in dual-function radar and communication (DFRC) systems. The main objective is to design a sparse transmit antenna array such that the bulk power of the transmit beam is concentrated towards the desired target along with the simultaneous transfer of information to multiple communication users. To tackle the problem, two iterative algorithms based on the majorization–minimization (MM) method and the method of alternating projections (MAP) are proposed. Both the proposed algorithms deal with solving the simple least squares fitting problems, minimizing either the absolute or absolute squared error between the synthesized and desired power pattern. The aforementioned optimization problems are solved under the constraints that the designed array operates at maximal power and all the sidelobes of the transmit beam are strictly below a specified threshold. In addition, the designed arrays can transmit the information embedded in the sidelobes of the transmit beam in the form of modulated symbols to multiple users, thereby ensuring the reliable performance of the communication subsystem. The sparsity of the array is achieved by adding the sparsity promoting regularization term in the design objectives. Through various numerical simulations, we illustrate the performance of the proposed approaches in terms of convergence, the matching mean square error, and the sparsity of the designed transmit antenna array.