基于预编码改进的多载波系统ICI消除方案

针对基于正交频分复用(orthogonal frequency division multiplexing,OFDM)的新型多载波系统，提出统一的预编码应用模型，该模型可以通过配置不同的预编码方案和多载波调制得到多种实例系统，同时可基于互模糊函数对信号和载波间干扰(inter-carrier interference,ICI)进行量化分析，并利用原始信号的统计特性得到应用预编码后系统的载干比(carrier-to-interference power ratio,CIR)。在该模型的基础上，提出一种基于双向抵消载波间干扰思想的预编码方案，此方案将目标载波2个方向的多个子载波加权进行ICI抵消，可以更好解决系统中普遍存在的载波间干扰问题，获得更强的抗频偏能力。仿真结果表明，在实例系统OFDM和滤波正交频分复用(filtered orthogonal frequency division multiplexing,F-OFDM)中，所提方案均较传统的预编码抑制ICI方案约有0.7 dB的CIR性能改善，较未编码的系统约有3.5 ~6 dB的改善。

Improved ICI cancellation scheme for multi-carrier system based on precoding

This paper proposes a unified precoding application model for the orthogonal frequency division multiplexing(OFDM)-based multi-carrier systems, which can obtain multiple instances by configuring different precoding and multi-carrier modulation schemes. The model can simultaneously quantize and analyze the signal and inter-carrier interference (ICI) based on the mutual cross-ambiguity function, and obtain the carrier-to-interference power ratio (CIR) of the precoded system by the statistical characteristics of the original signal. Based on the proposed model, this paper proposes a precoding scheme with bidirectional ICI cancellation. The scheme weights multiple subcarriers in the two directions of the target carrier to perform ICI cancellation, which can better solve the ICI problem that is ubiquitous in the system and obtain stronger anti-frequency offset capability. The simulation results prove that in the instances of model e.g. OFDM and filtered OFDM (F-OFDM), the proposed scheme has nearly 0.7 dB CIR performance improvement compared with the traditional precoding ICI suppression scheme, and nearly 3.5~6 dB improvement compared with the unprecoded system.