Proceedings Article | 23 January 2023
KEYWORDS: Signal detection, Oscilloscopes, Geometrical optics, Time metrology, Optical fibers, Correlation function, Signal processing, Optical testing, Interference (communication), Free space optics
Compared with the traditional electronic line delay, the optical fiber delay line has the advantages of small size, light weight, wide bandwidth, low loss, and strong anti-interference ability. Fiber optic transmission delay measurement technology has a wide range of applications in early warning, communications, navigation, ranging, remote mapping, etc. Traditional optical methods of measuring time intervals can achieve a high degree of accuracy, but they are complex to use, difficult to set up, susceptible to interference, have a limited measurement range and are expensive. Time interval measurement methods for electrical signals can be broadly classified into two categories: analogue and digital. With the continuous development of semiconductor technology and the increasing maturity of digital circuit technology, digital methods now have an increasingly wide range of practical applications, not only because analogue methods are very sensitive to ambient temperature, but also because they require relatively long conversion times, are susceptible to external disturbances and are difficult to integrate. Correlation detection is a very common method for processing signals in the time domain, and is used in correlation detection, delay measurement and signal identification.
