摘要
针对OFDM系统的量化噪声问题,研究适于多载波信号的新型量化噪声整形器.比较单零点∑△与多零点∑△调制器的适用性,进而给出多零点∑△调制器用于OFDM系统的完整方法、理论及仿真分析.研究表明,无过采样多零点∑△调制器可有效减小OFDM系统的量化噪声,具有比传统单零点∑△更好的整形性能.3bit量化、信噪比6d B时,系统误比特率性能改善3个数量级;但受限于非循环的量化噪声结构,多零点∑△调制器未能达到完全消除量化噪声的理想状态.
To solve the problem of quantization noise in OFDMsystems,a study on a novel quantization noise shaper for multi-carrier signal is presented. The paper first compares the applicability of two kinds of sigma-delta modulators with the single zero and multiple zeros. Then it gives the complete scheme,theory and simulation analysis of the multi-zero sigma delta modulator for OFDMsystems. Studies showthat the multi-zero sigma delta modulator without oversampling can effectively reduce the quantization noise in OFDMsystems,and performs better in noise shaping. Under the conditions of 3bit quantization and 6d B SNR,the bit error rate of the system deceases by 3 order of magnitude. But limited by the non-cyclic quantization noise structure,the proposed modulator cannot achieve the ideal state of eliminating the quantization noise completely.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2017年第1期61-66,共6页
Acta Electronica Sinica
基金
国家自然科学基金(No.61302062
No.61501324)
天津市应用基础及前沿技术研究计划(No.13JCQNJC00900)
