Patent ID: 7278314

Claim:
An obstacle detection system comprising: a plurality of ultrasonic sensors, wherein each ultrasonic sensor has ultrasonic signal transmitting means for transmitting an ultrasonic signal, wave transmitting and receiving means for transmitting an ultrasonic wave responsive to the ultrasonic signal and receiving reflected wave, and receiving filtering means for performing filtering processing on the received wave of the ultrasonic signal; and a control unit communicable with the plurality of ultrasonic sensors, wherein the control unit is equipped with processing means for performing processing of transmitting frequency setting information that contains a transmission frequency of the ultrasonic signal and a center frequency in the filtering processing to the ultrasonic sensor, the ultrasonic signal transmitting means has transmission frequency setting means for setting up a transmission frequency of the ultrasonic signal according to the frequency setting information, wherein the control unit includes a memory storing a combination of transmission frequency and center frequency for each of the plurality of ultrasonic sensors, wherein the receiving filtering means is equipped with center frequency setting means for setting up a center frequency in the filtering processing according to the frequency setting information.