【摘要】 针对基于VM IMO-OFDM系统的无线传感器网络目的节点中的多频偏和信道冲激响应估计问题提出了一种基于导频的联合估计算法。由于每个传感网中继节点都具有一个独立的晶振,每个中继节点到目的节点的链路都有着不同的频偏和信道冲激响应等参数。在目的节点直接对多个参数进行估计是个多维非线性问题,复杂度较高。提出的算法基于特殊设计的训练序列,目的节点通过序列相关处理将各个中继节点的信号进行分离,将复杂的多维非线性问题转换成一维线性问题。通过分析表明,各个频偏值可以通过对相关结果进行线性变换得到,然后基于频偏的估计值,由最大似然准则可估计出信道冲激响应。更多还原

【Abstract】 Based on the pilot of VMIMO-OFDM system,this paper proposed a jointly estimation algorithm for solve estimation problem between the multiple carrier frequency offset(CFOs) and channel impulse response(CIRs) at the wireless sensor network’s destination node.As each transmitter-to-receiver link in wireless sensor networks had an individual CFO and CIR parameters with its local oscillator,so directly estimation all the parameters had become a multi-dimensional nonlinear problem.Based on the specially designed training sequences,the destination node could decouple the signal from different relay nodes by correlation and simplify the MD nonlinear problem to linear.The multiple CFOs could be identified from the correlation result,so that the CIRs could be estimated according to the maximum-likelihood principle.更多还原