Virtual Instrument for the Estimation of the Time Delay Using Conditional Averaging of Random Signals

摘要

The paper presents a virtual instrument (VI) which allows to carry out the simulation and experimental studies of the various statistical methods of random signal time delay measurement including the methods developed by the authors which employ the conditional averaging of signals. The VI includes generators and oscilloscope and also a PC with the DAQ card and the software developed in the LabVIEW environment. The instrument allows to model and generate the stochastic signals with definite statistical parameters, to acquire signals from external sources, and to perform the time delay estimation with the use of several methods. This study describes the principle and properties of the method which employs the conditional average value of the absolute value of delayed signal (CAAV), and some exemplary results of this method with the use of the built instrument are presented. The results obtained with the CAAV method have been compared with the results obtained by the best known and used at the measurements of random signal time delay method of cross correlation (CCF). It has been found that the CAAV method is featured with lower time delay variance than the CCF within the signal-to-noise ratio higher than 0.35.