Optimal Numerology in OFDM Systems Based on Imperfect Channel Knowledge

摘要

In order to meet the user requirements in the next generation radio access technology, the ongoing standardization within 3rd Generation Partnership Project (3GPP) offers flexibility in terms of employing mixed numerology. The term numerology refers to the parametrization of the multicarrier modulation scheme. In this paper we consider Single User Single-Input-Single-Output (SU-SISO) Orthogonal Frequency Division Multiplexing (OFDM) under the doubly-selective channel. We investigate the optimal pilot-symbol pattern, accounting not only for Intercarrier Interference (ICI) and Intersymbol Interference (ISI) caused by channel conditions, but also considering the channel estimation error as a consequence of imperfect channel estimation. As a cost function for our optimization we choose the upper bound of the constrained capacity and apply it for different numerology. We show the throughput results in terms of different numerology and compare it to an LTE-compliant scenario.