LAUSR

Amplitude error of signals sampled by equivalent-time sampling, which is commonly used in commercial ultrawideband (UWB) radar such as ground-penetrating radar (GPR), is caused by additive noise and timing jitter. A simple method is developed to quantify the two types of noise separately by employing their different statistical characteristics. The method correlates the time derivative of signal and amplitude error and estimates the error distribution. The method is demonstrated with synthetic equivalent-time sampled signals containing both additive noise and timing error. The result shows that the method gives reasonably accurate estimates of signal-to-noise ratio and timing error distribution within a few percent of error. In addition, an example of the method applied to real radar signals is presented. Despite the fact that the method is based on the amplitude error distribution calculated by the sample mean of recorded signals, which is known to be biased, the influence of the bias can be minimized in the method by using a part of signals where the bias tends to be small.