| 摘要 |
PROBLEM TO BE SOLVED: To provide a relatively inexpensive object detector of relatively simple detector constitution, capable of enhancing detection precision of a stationary object in a near distance. SOLUTION: A microwave of 10.525 GHz is used as a transmission signal. Antenna pitches between reception antennas 5, 7, 9 are at set about 15 mm of 1/2 wave length of a standing wave of the microwave and 2.4 mm which is not a multiple thereof. The first, second and third standing waves of analog signals are converted respectively into digital signals by an A/D converter 29 to be stored in a memory part 33. The first - third full-wave rectification processing parts 35-39 conduct respectively processings corresponding to full- wave rectifications to the respective digital data corresponding to the first - third standing waves, using as a reference output voltages from the first - third direct current amplifying circuit 21-25 sides when the transmission is not emitted from a transmission antenna 3. An adding part 41 conducts processing for summing up the digital data after the processing, and a voltage level comparing part 45 checks whether the digital data provided therein is larger than a threshold voltage level or not.
|
