ETC: Enhancing Transportation Computation With IRS-Enabled Wireless Powered MEC Systems

This paper explores the computation enhancement problem in an intelligent reflecting surface (IRS) enabled wireless powered mobile edge computing system serving the intelligent transportation relying on powerful computational support. Initially, in the downlink, the base station (BS) with edge server transmits energy signals to the battery-powered roadside units (RSUs) with computing capabilities, which are grouped into distinct clusters. Subsequently, RSUs leverage the harvested energy for local computing and offloading their tasks to the BS by using a hybrid rate splitting multiple access (RSMA) and time division multiple access (TDMA) strategy. Finally, the computed outcomes from the edge server are transmitted for integration with the computations carried out locally at the RSUs. The objective is to maximize the minimal computation rate of RSU clusters, where the transmit power of the BS and RSUs, the downlink and uplink beamforming of the IRS, the CPU frequency of the RSUs, and the time slot assignment are jointly optimized. To address the bottleneck issues constraining computation rate, this paper proposes an iterative algorithm that combines sequential rank-one constraint relaxation and block coordinate descent methods. Ultimately, the simulation results confirm the effectiveness of the proposed algorithm in enhancing the weakest link constraining the system computation rate when contrasted with the baseline algorithms.