Resource Allocation for Dynamic TDD-Enabled Integrated Sensing and Communication Systems

In this paper, we investigate a dynamic time division duplex (DTDD) enabled integrated sensing and communication (ISAC) system, in which access points (APs) mode, bandwidth and transmit power can be flexibly configured. To obtain the best tradeoff between communication and sensing performance, we maximize the sum of downlink (DL) and uplink (UL) transmission rates under the constraints of Cramer-Rao lower bound (CRLB) and the maximal transmit power by jointly optimizing the power/subcarrier allocation and APs mode selection. To deal with the proposed nonconvex problem, we adopt the alternating optimization (AO) method to divide the original problem into two subproblems. The first subproblem is related to power/subcarriers allocation, which is equivalently transformed into a Semidefinite Programming (SDP) problem and eventually solved by the penalized convex-concave procedure (PCCP) method. The second subproblem is a quadratic integer problem related to APs mode selection, which is transformed into a convex quadratic integer problem that can be efficiently solved by the convex optimization toolbox. The numerical results demonstrate the tradeoff between the total transmission rate and sensing performance with different parameter configurations. Compared with existing schemes, our proposed scheme has significant advantages in terms of tradeoff performance.