Analysis of cell spectral efficiency in 3GPP LTE systems

Abstract

A novel analytical framework is presented to evaluate resource consumption, error ratio and spectral efficiency on PHY, MAC and RLC layer in 3GPP LTE systems. Thereby, various aspects of the different LTE system layers are modeled: On PHY layer, association of user terminal to a radio access point, probabilistic radio channel states, adaptive modulation and coding, overhead in LTE radio frame, turbo coded M-QAM block error rate, and Chase combining are taken into account. On MAC layer, hybrid-ARQ protocol, resource assignment failure, and feedback misdetection are accounted for. On RLC layer, segmentation of a RLC SDU into several RLC PDUs, selective repeat - ARQ protocol, feedback loss, and timer for upcoming feedback to be waited for are considered. With the framework, various performance criteria can be evaluated: Resource consumption, error ratio and spectral efficiency are assessed as CDF for any location in a cell, multi-cell scenario map with expected value for each location, CDF for a cell, and expected value and percentile for a cell.