High-Precision Ranging of Ultra-Close Liquid Level

In the process of high-precision liquid level measurement, radar has to solve the problem of ultra-close liquid level’s high-precision survey sometimes, such as the distance of just a few tens of centimeters. For single-channel radar, the echo signal is a series of real data; and its spectrum will become no longer simple when the liquid level is very close. Since for real data, the positive and negative frequency components will superimpose on each other in its spectrum. In this case, the existing high-precision liquid level measurement algorithms are no longer effective. In order to solve this problem, the authors investigate a new high-precision liquid level measurement method. In this method, the echo signal is windowed first; and then a corresponding interpolation algorithm is designed aiming at the window type; finally, iterate the interpolation algorithm, and the high-precision ranging result is obtained. Experiments show that this method can realize the high-precision ranging of ultra-close liquid level. This method can be used for high-precision ranging radar, such as liquid level meter radar, which is of great practical significance.