Introduction of MPR information for enhanced multi-cluster scheduling in LTE-A uplink

Abstract

Against previous Long Term Evolution (LTE) re-leases, LTE-Advanced (LTE-A) allows the use of non-contiguous resource allocation in the uplink (UL). This feature leads to an increase in spectral efficiency thanks to link performance gains obtained from frequency diversity. At the same time noncontiguous allocations bring higher peak to average power ratio (PAPR) and so potentially higher inter-modulation and adjacent channel leakage-power ratio (ACLR). Power de-rating has been proposed as a means to avoid this problem and thus user equipments (UEs) must reduce their maximum transmitted power. However, the additional link loss on power limited UEs partially counteracts the gain brought by multi-cluster allocation. In this sense, this paper proposes to include Maximum Power Reduction (MPR) information in opportunistic scheduling decisions. The new scheduling proposal is able to determine whether multi-clustering leads to a net gain in instantaneous throughput or if localized allocation is preferred. Results show that this method improves cell throughput and allows making a smarter use of clustered transmission.