초록 ▼

An ultrasonic intrusion detection system having means for transmitting and receiving ultrasonic energy within a protected zone and generating an alarm when a moving object is present in the protected zone is supplemented to provide multiple independent response zones utilizing the same transmitter f

An ultrasonic intrusion detection system having means for transmitting and receiving ultrasonic energy within a protected zone and generating an alarm when a moving object is present in the protected zone is supplemented to provide multiple independent response zones utilizing the same transmitter for all zones but individual receiver modules which can be added to the existing transmitter-receiver system to provide protection for additional independent zones with associated indicators for selectively indicating those zones which have been triggered by the presence of an intruder or other moving object.

대표청구항 ▼

A multiple zone ultrasonic intrusion detection system comprising: a master oscillator for generating power at ultrasonic frequency; first transmitting transducer means energized by said master oscillator for radiating ultrasonic wave energy into a first zone; first receiving transducer means for rec

A multiple zone ultrasonic intrusion detection system comprising: a master oscillator for generating power at ultrasonic frequency; first transmitting transducer means energized by said master oscillator for radiating ultrasonic wave energy into a first zone; first receiving transducer means for receiving ultrasonic wave energy from said first zone and converting received waves into electric signals; second transmitting transducer means energized by said master oScillator for radiating ultrasonic waves into a second zone; second receiving transducer means for receiving ultrasonic waves from said second zones and converting received waves into electric signals; means for processing said electric signals from said first and second receiving transducer means to recover separate Doppler shifted components arising from moving objects within the respective zones; and means responsive to said Doppler shifted components of predetermined magnitude for selectively indicating at a central location which of said zones contains a moving object.