172263 ⎘
Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using ultrasonic, sonic or infrasonic waves; Systems for determining direction or position line using a comparison of transit time of synchronised signals transmitted from non-directional transducers or transducer systems spaced apart, i.e. path-difference systems the synchronised signals being pulses or equivalent modulations on carrier waves and the transit times being compared by measuring the difference in arrival time of a significant part of the modulations
Acoustic horn phased array
#2Consistent arrival time measurement and determination of discharge polarity
#3Ultrasonic locationing system using a dual phase pulse
#4Two pass detection technique for non-echo pulsed ranging
#5Location system
#6Location system
#7Autolocating underwater beacon and method for deployment thereof