| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an object detector and washer unit for urinal equipped with it in which the output of microwave Doppler sensor utilizes interference between each sensor to prevent the sensor output from degradation in S/N ratio and further inhibit degradation in sensitivity. <P>SOLUTION: This object detector 1 includes microwave Doppler sensor 10 for generating differential signal from difference in frequency between radio wave transmitted to prescribed direction and its reflected wave, and controller 13, which allows intermittent operation of the above microwave Doppler sensor 10 to detect object M based on its signal Sig1. It also has interference detector 14 which detects occurrence of radio wave interference caused by other microwave Doppler sensor, when frequency of difference between the transmitted radio wave frequency and frequency of the radio wave transmitted from the above other microwave Doppler sensor is contained in differential signal Sig1. The controller 13 determines the differential signal Sig1 output from the microwave Doppler sensor 10, when the interference detector 14 has detected occurrence of radio wave interference as invalid, and then detects the object M, without using the above differential signal determined as invalid. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
