Patent ID: 9618617
Date: 2017-04-11
CPC Classifications: G01F,G01S

Claim:
1. A method of measuring a level of a material in a tank, comprising: generating a first secondary reference (FSR) signal when a reference pulse is transmitted into said tank and generating a second secondary reference (SSR) signal when an echo signal including an echo pulse responsive to said reference pulse is received; storing a plurality of said FSR signals and a plurality of said SSR signals; transferring said plurality of said FSR signals and said plurality of said SSR signals at a correlator block; said correlator block calculating a plurality of correlation function values (CFVs) which have magnitudes reflecting a degree of matching between pairs comprising ones of said plurality of said SSR signals with their associated one of said plurality of said FSR signals including a maximum CFV result; using said maximum CFV result calculating a time interval (Tm), and determining said level of said material in said tank from said Tm.