Measurement method of pulse signal arrival time difference

Abstract

The invention provides a measurement method of pulse signal arrival time difference. The measurement method comprises the following steps: smoothly filtering envelope of a first pulse signal and a second pulse signal which are received; detecting pulses through a fixed threshold method, and respectively recording sampling time and corresponding sampling point values, higher and lower than preset threshold values, of leading edges and lagging edges of the first pulse signal and the second pulse signal; obtaining pulse arrival time and pulse finishing time of the first pulse signal and the second pulse signal through a linear interpolation algorithm; and respectively calculating pulse intermediate time of the first pulse signal and pulse intermediate time of the second pulse signal, and subtracting the pulse intermediate time of the first pulse signal from the pulse intermediate time of the second pulse signal to obtain the pulse signal arrival time difference. According to the measurement method, inherent deviation can be overcome effectively, estimation variance is one half of that of a traditional method, and time difference measurement performance can be improved obviously.

Description

technical field [0001] The invention relates to the technical field of signal parameter estimation, in particular to a method for measuring the time difference of arrival of pulse signals. Background technique [0002] Passive positioning technology refers to the emerging positioning technology that passively receives the radiation signal of the target radiation source to determine its position, and the time difference of arrival (TDOA, Time difference of arrival) between the observation points is the key to determine the spatial geometric position of the target radiation source. One of the main parameters. Pulse signals are widely used in communication, navigation, and radar, and their time difference of arrival measurement has become an important determinant for passive positioning of such radiation source targets. [0003] The time difference of arrival of the pulse signal refers to the time of arrival (TOA, Time of arrival) difference between the two observation points....

AI Technical Summary

Problems solved by technology

However, the actual received pulse signal of the radiation source is bound to be interfered by noise, especially under the condition of low SNR, the direct envelope detection method often introduces a large TOA measurement error, which leads to a relatively large TDOA estimation error between observation points. Big

In addition, due to the directional characteristics of the antenna beam of the radiation source and the distance between the observation points, there is a certain difference in the pulse amplitude arriving at each observation point, and the fixed threshold detection method will lead to an inherent bias in the TDOA estimation

In order to overcome this problem, the existing methods mainly adopt the adaptive threshold method, which adjusts the threshold according to the pulse amplitude, but this method faces the problem of double threshold detection, and needs to perform initial detection and measure the pulse amplitude, which is more complicated to implement.

Images