基于最小二乘的极低频微弱信号实时检测方法

Novel approach of real-time ELF weak signal detection based on least square algorithm

极低频信号由于对金属介质具有良好的穿透性,现被应用于管道机器人的示踪定位系统中。实现极低频信号的可靠检测是保证示踪定位系统正常工作的关键,现有检测系统中使用的检测方法易受噪声干扰,经常出现误报与漏报,可靠性低。根据实际工程中极低频信号动态范围大、观测时间有限的特点,提出了一种基于最小二乘的极低频信号实时检测方法,构造了检验统计量并通过MATLAB仿真分析了窄带高斯噪声情况下的检测性能。以DSP为核心设计实现了基于最小二乘的极低频磁场信号检测系统,通过仿真与工程实验验证了所提出方法的优越性。在信噪比为3 dB,恒虚警概率为1%的条件下,检测概率可达90%,完全满足管道机器人示踪定位系统中极低频信号实时检测的要求。

Extremely low frequency （ELF） signal has the ability to pass through metal pipes, so it is applied to the localization system of pipeline robot. However, the ELF weak signal detection method currently used is easily interfered by noise and has low detection probability and high false alarm probability, which make the system unreliable. Because ELF signal emitted from the pipe has wide dynamic range and is time limited during work, a novel real-time ELF weak signal detection approach based on least square algorithm is presented. A new statistic is con- structed and its performance is analyzed by Matlab simulation under narrowband Gaussian noise condition. An ELF signal detection system based on DSP was completed and the superiority of the method is proved by experimental results. In the condition of 3 dB SNR and 1% false alarm probability, the detection probability reaches 90%, which meets the requirement of real-time signal detection in the localization system of pipeline robot.