2004 年 40 巻 12 号 p. 1199-1204
A frequency modulated continuous wave (FMCW) type electromagnetic wave radar is generally used to measure the distance of an object. The principle is that mixing of the transmitted and received wave signals of the radar makes a beat signal whose frequency corresponds to the distance. A frequency analysis of the beat signal thus enables the measurement of the distance. However, the sensing system until now has been mainly devoted to the measurement of the distance of one object.
The paper proposes a sensing system which measures the locations of plural objects accurately. This is achieved by modeling the beat signal as the sum of several sinusoidal waves and estimates the distinct frequencies by applying the maximum likelihood method. The validity of the system is verified with experiments on two objects of a car and a man.