Universal-filtered multi-carrier technique for wireless systems beyond LTE

TLDR

The paper proposes a universal‑filtered multi‑carrier (UFMC) scheme to mitigate inter‑carrier interference in OFDM systems. UFMC applies a filter to blocks of consecutive subcarriers, reduces sidelobes, and is evaluated with coordinated multi‑point reception and CFO analysis against CP‑OFDM using simulations. Simulation results show UFMC outperforms CP‑OFDM under both perfect and imperfect frequency synchronization.

Abstract

In this paper, we propose a multi-carrier transmission scheme to overcome the problem of intercarrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) systems. In the proposed scheme, called universal-filtered multi-carrier (UFMC), a filtering operation is applied to a group of consecutive subcarriers (e.g. a given allocation of a single user) in order to reduce out-of-band sidelobe levels and subsequently minimize the potential ICI between adjacent users in case of asynchronous transmissions. We consider a coordinated multi-point (CoMP) reception technique, where a number of base stations (BSs) send the received signals from user equipments (UEs) to a CoMP central unit (CCU) for joint detection and processing. We examine the impact of carrier frequency offset (CFO) on the performance of the proposed scheme and compare the results with the performance of cyclic prefix based orthogonal frequency division multiplexing (CP-OFDM) systems. We use computer experiments to illustrate the efficiency of the proposed multi-carrier scheme. The results indicate that the UFMC scheme outperforms the OFDM for both perfect and non-perfect frequency synchronization between the UEs and BSs.