  In this paper, the problem of low-latency communication and computation
resource allocation for digital twin (DT) over wireless networks is
investigated. In the considered model, multiple physical devices in the
physical network (PN) needs to frequently offload the computation task related
data to the digital network twin (DNT), which is generated and controlled by
the central server. Due to limited energy budget of the physical devices, both
computation accuracy and wireless transmission power must be considered during
the DT procedure. This joint communication and computation problem is
formulated as an optimization problem whose goal is to minimize the overall
transmission delay of the system under total PN energy and DNT model accuracy
constraints. To solve this problem, an alternating algorithm with iteratively
solving device scheduling, power control, and data offloading subproblems. For
the device scheduling subproblem, the optimal solution is obtained in closed
form through the dual method. For the special case with one physical device,
the optimal number of transmission times is reveled. Based on the theoretical
findings, the original problem is transformed into a simplified problem and the
optimal device scheduling can be found. Numerical results verify that the
proposed algorithm can reduce the transmission delay of the system by up to
51.2\% compared to the conventional schemes.
