摘要
提出了正交频分复用(OFDM)系统中一种新的载波频偏估计算法.载波频偏估计过程可分为获取和跟踪,其中,获取过程和时间同步是同时完成的.新算法可实现的最大载波频偏获取范围是整个信号带宽的一半.新的跟踪算法是一个最大似然算法,在加性白噪声高斯信道(AWGN)下,当N(训练序列长度的一半)等于128时,其性能比Schmidl算法提高约7.27dB;在多经信道下,当信噪比不是很高时,新算法仍具有优势.
A new carrier frequency offset estimation scheme in orthogonal frequency division multiplexing (OFDM) system is proposed. The carrier frequency offset estimation includes acquisition and tracking, and acquisition as well as timing synchronization can be performed simultaneously with high accuracy. The maximum acquisition range can be up to one half of overall signal bandwidth. The proposed tracking estimator is a maximum-likelihood estimator, and in AWGN channel, about 7.27 dB improvement is obtained compared to the Schmidl's algorithm when N=128; in multipath channel, the proposed algorithm works well at moderate SNR.
出处
《北京邮电大学学报》
EI
CAS
CSCD
北大核心
2004年第5期41-44,55,共5页
Journal of Beijing University of Posts and Telecommunications
基金
国家"863计划"项目(2003AA12331004)
关键词
频偏估计
多径信道
正交频分复用
Algorithms
Computer simulation
Maximum likelihood estimation
Multipath propagation