Centralized Resource Allocation Latency of SideLink Communication in NR V2X

Abstract

This paper investigates centralized resource allocation latency in the New Radio Vehicle-to-Everything (NR V2X) Mode 1. It presents a new resource partitioning technique among Road Side Units (RSUs) supervised by a cellular base station called Partial Time Reuse (PTR) in a highway scenario. This technique divides the vehicle's transmission period (broadcast periodicity) into two intervals for two adjacent RSUs. Each RSU divides its interval duration into two shorter intervals used by vehicles located in central and edge RSU coverage areas to increase the frequency reuse distance and decrease the resource re-allocation delays. Furthermore, we proposed the Centralized-Estimation and Reservation Resource Allocation (CERRA) algorithm as an alternative resource allocation method to the Configured Grant (CG) method proposed by the 3rd Generation Partnership Project (3GPP). C-ERRA works by listing all addresses of resources that will be accessible in an estimated period using a decremental Re-selection Counter (RC). The cellular base station generated RC value in each resource (re)allocation. PTR performance is compared with another spectrum partitioning technique termed Partial Frequency Reuse Technique (PFR), which divides the spectrum instead of time. However, C-ERRA performance with PTR shows excellent results compared with CG with PFR in re-allocation delay. C-ERRA with PTR and PFR has displayed promising results in frequency ruse distance and packet reception ratio.