TDMA-Based Multi-User Binary Computation Offloading in the Finite-Block-Length Regime

Multi-user computation offloading inherently involves the allocation of communication resources among the offloading devices. Since the devices require timely results, that allocation ought to be guided by the fundamental rate limits for finite block lengths, rather than the classical (asymptotic) limits. We develop an efficient algorithm for such an allocation. It includes a relaxation-rounding approach that is based on a customized incremental rounding scheme for the block lengths. A special feature is that the relaxation is tightened in such a way that rounding a feasible solution to the relaxed problem is guaranteed to generate a feasible integer block length. By exploiting a closed-form approximation of the transmission powers, our design approach reduces to successively solving convex approximation problems over the transmission rates alone.