RADIO SOURCE AND DIRECTION FINDER ORIENTATION DETERMINING METHOD Russian patent published in 2011 - IPC G01S5/04 

FIELD: radio engineering.

SUBSTANCE: radiated signal is received with direction-finding antenna consisting of M identical antennae the focal axes of which are shifted relative to each other in direction finding plane so that adjacent antenna directivity diagrams form identical direction-finding characteristics, and the sum of M antennae superimposes the whole 360° surveillance area; received signals are distributed along three identical receiving devices; at that, view of the whole surveillance area is performed by electronic switching of M outputs of direction-finding antenna to inputs of three receiving devices so that to inputs of receiving devices for the time of determination of radio source direction there always simultaneously connected are three adjacent antennae; in each of the receiving devices the received signals are distributed along identical frequency sub-bands in each of which the signals are amplified and detected; detection result is amplified with logarithmic video amplifier; power of amplified signals is measured considering corrections for nonidentity of transfer factors of receiving devices, which is determined and stored at periodic calibration of receiving devices in each frequency sub-band and in dynamic range of input signals; as per ratio of powers there determined is frequency sub-band in which the signals has been received, and for the signals having maximum level in the receiving device connected to central antenna of the three adjacent antennae; radio source direction is determined as per direction-finding characteristics formed with central antenna and one of the adjacent antennae (right or left), in which the signal power is higher as per the appropriate formulae. At calculations the slope value of direction-finding characteristic is assumed considering frequency sub-band in which the signal has been received. Direction finder includes multi-beam direction-finding antenna consisting of M identical antennae, nondirectional antenna, four identical receiving devices (three for direction finding and one for compensation of reception along side lobes of direction-finding antennae), each of which represents multi-channel receiver, switch, directional coupler, synthesiser of working frequencies, and analysis and control device.

EFFECT: increasing sensitivity and direction-finding accuracy and quick action.

2 cl, 5 dwg