摘要
OFDM中整数倍频偏的存在,虽然不会破坏子载波间的正交性,但会使得接收端FFT变换后的频域数据产生循环移位,解调出的数据错误率将达到0.5,也即完全错误。提出了一种基于导频的整数倍频偏估计方法,提取前后两个OFDM符号中的导频进行相关运算,相比于传统与本地导频相关的方法,文中方法在没有大量增加算法复杂度的情况下,克服了由于定时误差的影响而带来的影响。根据仿真结果可以看出,此方法在定时误差较大,且性噪比较低的情况下也有优良的误差估计性能,达到了预期的效果。
The existence of integer frequency offset in OFDM,can not destroy the orthogonality among subcarrier scan,but it causes circular shift of the frequency domain data after FFT.The data demodulated error rate will reach 0.5,that is totally wrong.Present a new algorithm based on pliot,use both before and after the two pilot OFDM symbols to calculate.Compared to the traditional and the local pilot the methods,the text method in the absence of a substantial increase in computational complexity of the situation,to overcome the impact of estimation difference caused by timing error.According to the simulation results,this method has excellent performance of error estimation at large timing error low SNR,is to achieve the desired results.
出处
《计算机技术与发展》
2010年第7期28-31,共4页
Computer Technology and Development
基金
国家发改委CNGI2005示范工程项目(CNGI-04-4-2D)