User Grouping and Resource Allocation for Joint Communication and Positioning in mmWave Multi-cell Networks

B5G/6G expands a new application scenario of joint communication and positioning which can simultaneously provide high-quality communication and positioning services. Millimeter wave (mmWave) and massive Multiple Input Multiple Output (MIMO) can help systems to achieve high-quality communication and generate high-directional beams to assist positioning. In this paper, the proposed Structured Perturbed Orthogonal Matching Pursuit (SPOMP) could alleviate the pilot pollution in massive MIMO systems and break the resolution of angular estimation. Based on the above super-resolution estimation, we develop a dynamic two-stage multi-cell user grouping scheme to reduce interference and improve resource utilization. Combined with the grouping results and our derived performance metric, a joint optimization problem for power and bandwidth allocation is proposed to maximize the comprehensive performance of joint communication and positioning while guaranteeing performance bounds. An effective cyclic iteration algorithm based on Alternating Direction Method of Multipliers (ADMM) is present to solve the proposed optimization problem. Numerical results show that the proposed joint user grouping and resource allocation scheme achieves a larger rate-accuracy region and a better multi-cell service performance balance compared to conventional schemes.