Resource Allocation and Blocklength Selection for Low-Latency Vehicular Communications

In vehicular communications, the vehicle-to-vehicle (V2V) links have strict requirements on transmission latency. However, the widely utilized infinite blocklength coding for the V2V links results in inevitable high latency. With finite blocklength coding in the V2V links, this letter devotes allocating power, spectrum, and blocklength in the vehicle-to-everything (V2X) networks, which minimizes the V2V links' latency subject to constraints on the reliability of the V2V links and the ergodic capacity of the vehicle-to-network (V2N) links for the case where each V2V link can reuse the spectrum of at most one V2N link. By transforming the data rate outage probability into a tractable form and using bisection search, the optimal solution is obtained by the proposed algorithm. The simulation results validate the effectiveness and superiority of our proposal.