A Method of Equivalent-sampling Time-spreading Distance Measurement Applied to Radar Water-level Gauge

The radar water-level gauge, a kind of non-contact apparatus for water level measurement, measures distances between the sensor and water surface by electromagnetic wave carrier way and then calculates out actual water level numbers. Due to rate of propagation of electromagnetic wave close to speed of the light, the time interval is too short when transmission at close range. To reach centimeter-level accuracy of distance measurement, we should get picosecond accuracy of measurement time. There are some problems for common high-precision time measuring methods such as high cost and complicated implementation model. An equivalent-sampling time-spreading distance measurement is described by which centimeter-level accuracy can be realized within measuring ranges of a radar water-level gauge. That measurement method has been applied to actual products.