Passive location method for sound-emitting target processes signals from electroacoustic transducer device for providing signal level characteristic as function of distance for estimation of target range

摘要

The passive location method uses a transducer device (10) with spaced electroacoustic transducers (11), with defined phase shift and/or time delay of the reception signals for focusing onto focal points along a target direction and conphase addition of the delayed signals for providing a focus signal for each focal point. The level of the focus signal in dependence on the distance of the focal point from the transducer device is determined for each target direction (19), for providing a signal level characteristic as a function of the distance, the target range estimated from a detected maximum of the signal level characteristic.