梯度映射耦合频域变换的OFDM信号精确接收算法  

OFDM signal precise receiving algorithm based on gradient mapping and frequency domain transform

作　　者：范晖[1] 夏清国[2] 黄健[1] 

机构地区：[1]西京学院信息工程学院,西安710123 [2]西北工业大学计算机学院,西安710072

出　　处：《电子测量与仪器学报》2017年第11期1766-1773,共8页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(51405382);国家自然科学基金(60970070);陕西省教育厅专项科研计划(16JK2239)资助项目

摘　　要：针对现有的正交频分享用(OFDM)网络信号接收过程中存在带外杂波扩散严重、信号投影难以匹配以及误码率较高等难题,提出了基于梯度映射机制的子载波OFDM网络信号精确接收算法。首先,通过快速傅里叶变换及其逆变换,并联合插值技术,构建最小均方差预估抑制机制,并采用带通滤波技术对带外杂波进行全频域消除;随后,基于实部及虚部信号的数字特征,构建梯度映射机制,对信号投影点与投影象限进行匹配,降低OFDM网络误码率。仿真实验表明,与当前幅度滤波限制算法(amplitude filter algorithm,AF)、中波带频率抑制算法(wave band frequency suppression algorithm,WBFS)相比,所提算法具有更低的误码率,分别降低了2个、3个量级,以及更高的信号增益强度,在莱斯信道条件下,分别提高了20.5%、41.63%,且功率谱性能与理想状态下的OFDM信号最为接近。所提算法具有理想的信号接收精度与抗衰落性能,具有一定的实际部署价值。In order to solve these defects as serious dispersion of band clutter, signal projection difficult to match and the high bit error rate during the network signal reception process, a precise receiving algorithm for sub-carrier OFDM networks based on gradient mapping mechanism was proposed. Firstly, minimum mean square predictive inhibitory mechanism was constructed by fast Fourier transform and its inverse transform, as well as interpolation technique, and band pass filtering was used to eliminate the out of band clutter in full frequency domain. Then the gradient mapping mechanism was constructed based on real and imaginary part signals of digital features to match the projection points of the signal with the projected quadrants for reducing the network error rate. The simulation results show that this proposed algorithm has lower error rate reducing by 2, 3 orders, as well as higher signal gain intensity, increasing 20.5% and 41.63% respectively under the Rician channel condition, and the power spectrum performance is closest to the ideal state compration compared with the current amplitude filter algorithm and the wave band frequency suppression algorithm. This algorithm has ideal signal reception precision and anti-fading performance with certain practical deployment value.

关 键 词：OFDM网络 信号接收 最小均方差预估抑制 带通滤波 梯度映射 信号增益 

分 类 号：TP393.04[自动化与计算机技术—计算机应用技术] TN911.25[自动化与计算机技术—计算机科学与技术]