Performance of Coordinated Scheduling in Downlink LTE-A under User Mobility

Abstract

Resource scheduling, in LTE, plays a pivotal role to determine the user equipment (UE) throughput. The performance of a scheduler is primarily affected by the associated latency and UE mobility. These can significantly deteriorate the overall system efficiency. Coordinated multipoint (CoMP) is considered as one of the primary downlink transmission technique to improve data transmission efficiency. A key feature of CoMP is coordinated scheduling (CS). This coordination can be centralized or distributed. These improve interference management but at the cost of an increased latency and backhaul traffic, which potentially reduces the overall achievable throughput of the system. The effect becomes significantly important when UE mobility is considered which further degrades the received UE signal-to-interference-plus-noise-ratio (SINR). This degrades the performance of a scheduler. In this paper, we have simulated, analyzed and compared several LTE downlink parameters between centralized coordinated scheduling (C-CS) and distributed coordinated scheduling (D-CS) for various channel bandwidths and UE densities under multiple UE velocity to determine which CS scheme is comparatively more efficient for high velocity UEs and under large UE densitites.