IR-UWB能量检测接收机中基于门限的TOA估计

Threshold-based TOA Estimation in IR-UWB Energy Detection Receiver

为提高能量检测模式下脉冲超宽带(IR-UWB)测距的精度和可行性,该文提出基于最优门限和次优门限的两种到达时间(TOA)估计算法。最优门限算法以接收机信号统计特性与UWB小尺度衰减特性关系式为基础推导出门限选择的闭合表达式,并在最小均方误差(MMSE)指标下求解TOA估计值;次优门限算法以最优门限分析为基础,在虚警概率约束下使用牛顿迭代给出求解门限的递推算法。仿真表明,与同类算法相比,最优门限算法测距精度有较大提升;次优门限算法易于实现,且性能无明显下降。

In order to design precise and feasible ranging method with Impulse Radio Ultra Wide Band （IR-UWB） signal during energy detection, two new Time Of Arrival （TOA） estimation algorithms based on optimal and suboptimal thresholds are respectively proposed. For optimal method, with the relationship between energy＇s statistics in receiver and small-scale attenuation, a closed form of threshold is derived, and the TOA estimation is obtained under the Minimum Mean Square Error （MMSE）. For suboptimal method based on optimal threshold analysis, a recursive form of threshold selection using Newton iteration is developed with false alarm probability constraint. Through simulations, compared with other similar algorithms, the optimal method enhances greatly the ranging accuracy, the suboptimal method is easier to implement while its performance reduces less.