Improved scheduling decisions for LTE-A uplink based on MPR information

Abstract

Advanced (LTE-A) allows for non-contiguous resource allocation in the uplink. The aim is to increase the spectral efficiency by exploiting users’ frequency diversity gain. This feature implies that clustered-DFT-S-OFDM must be used in the uplink, no longer preserving the single carrier property of previous releases. Multi-cluster transmission brings an increase in the signal’s Peak-to-Average Power Ratio (PAPR) and so power de-rating must be introduced to control out-of-band emissions. Maximum power Reduction (MPR) can counteract the frequency gain and bring losses to the users’ performance. This paper proposes a novel scheduler that considers the MPR information. The packet scheduler’s main task is to evaluate the gain or loss in throughput of the multi-cluster transmission over a conventional contiguous one. Based on the Sounding Reference Signals (SRSs) channel estimation, the eNB can predict the multi- cluster transmission’s performance. Results show that enabling the MPR information in the scheduler adapts the transmission mode to each particular case, enhancing the system throughput