Improved N-continuous OFDM for 5G Wireless Communications

TL;DR

This paper introduces an improved time-domain N-continuous OFDM technique for 5G that reduces interference and complexity while maintaining sidelobe suppression, enabling more efficient wireless communication.

Contribution

It proposes a shortened smooth signal method in TD-NC-OFDM, providing lower complexity and interference with comparable sidelobe suppression to traditional methods.

Findings

Achieves similar sidelobe suppression as conventional NC-OFDM

Introduces negligible BER degradation

Significantly reduces computational complexity

Abstract

N-continuous orthogonal frequency division multiplexing (NC-OFDM) is a promising technique to obtain significant sidelobe suppression for baseband OFDM signals, in future 5G wireless communications. However, the precoder of NC-OFDM usually causes severe interference and high complexity. To reduce the interference and complexity, this paper proposes an improved time-domain N-continuous OFDM (TD-NC-OFDM) by shortening the smooth signal, which is linearly combined by rectangularly pulsed OFDM basis signals truncated by a smooth window. Furthermore, we obtain an asymptotic spectrum analysis of the TD-NC-OFDM signals by a closed-form expression, calculate its low complexity in OFDM transceiver, and derive a closed-form expression of the received signal-to-interference-plus-noise ratio (SINR). Simulation results show that the proposed low-interference TD-NC-OFDM can achieve similar suppression performance but introduce negligible bit error rate (BER) degradation and much lower computational complexity, compared to conventional NC-OFDM.