MB-OFDM-UWB系统同步及信道估计算法的改进与仿真  

Improvement and Simulation of Synchronization and Channel Estimation Algorithms for MB-OFDM-UWB Systems

作　　者：戈立军[1] 巨阿强[1] 李春雨[1] 吴虹[2] 苗长云[1] 缪竟鸿[1] 

机构地区：[1]天津工业大学电子与信息工程学院,天津300387 [2]南开大学电子信息与光学工程学院,天津300071

出　　处：《南开大学学报（自然科学版）》2013年第5期37-43,共7页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：国家自然科学基金(60872026);国家自然科学基金青年基金(61302062);天津市应用基础及前沿技术研究计划青年基金(13JCQNJC00900);天津市应用基础及前沿技术重点项目(09JCZDJC16900);天津工业大学青年基金(124030075)

摘　　要：针对标准MB-OFDM-UWB系统提出完整的同步及信道估计方案:采用基带跳频的多频带实现方案;提出基于自相关及能量检测的符号定时方法;分析基带跳频机制下单载波频偏对系统的影响,提出改进的最大似然估计方法;基于相位均衡补偿采样频偏引起的频域相位偏差;基于重叠相加及频域均衡对信道进行补偿,并同时补偿剩余符号定时偏差、载波相位偏差、载波频偏引起的幅度衰减、以及采样频偏引起的幅度衰减与整数倍样值偏差.该方案充分利用保护间隔的容忍力,保证系统性能的同时降低算法复杂度.仿真表明,3dB信噪比下系统误比特率达到10-5数量级.An intact scheme of synchronization and channel estimation was proposed for the standard MB-OFDM-UWB system, specially including： Adopting the baseband frequency hopping method for multiband achieving; Proposing maximum autocorrelation and minimum energy ratio algorithms for symbol timing; Presenting an improved maximum likely-hood algo- rithm for carrier frequency offset estimation on the basis of the analysis of the impact of single carrier frequency offset on the system in the proposed baseband hopping mode; Making up for the phase offset caused by sampling frequency offset by means of frequency-domain phase e- qualization; Using the overlapped add operation and frequency-domain equalization for channel compensation, the residual symbol timing error, the carrier phase offset, the amplitude attenu- ation caused by the carrier frequency offset and the sampling frequency offset, as well as the time-domain symbol timing errors caused by sampling frequency offset. The scheme makes full use of the tolerance of the cycle prefix, guaranteeing the system performance and the algorithm complexity. The simulation shows that the magnitude of bit error rate is 10-5 with a signal to noise ratio of 3 dB.

关 键 词：正交频分复用超宽带 符号定时 载波频偏同步 采样频偏同步 信道估计 

分 类 号：TN919.34[电子电信—通信与信息系统]