DIRECTIONAL-BEAM SWITCHING METHOD BASED ON OSCILLATION DATA

PURPOSE:To detect an underwater target accurately without using a complicated, large-scale pendulum mechanism by switching a sonar beam in response to the oscillation of a ship, and correcting the decrease in output level in response to the oscillating bearings angle from the front of the beam. CONSTITUTION:The sound wave signal, which is received with a wave transceiver l, is converted into the electric signal. The electric signals from the wave transceiver 1 are multiplied and added with a phasing device 2, and a plurality of the fan beams of the bearings are formed. Meanwhile, an oscillation-bearings detector 6 outputs the oscillating bearings the ship as the bearings signals of the X and Y axes into a beam switching device 3 and a correcting device 5. The beam switching device 3 switches the beam based on the oscillation data from the detector 6 and outputs the optimum signal with respect to the oscillation bearings. The outputs of the fan beams are multiplied in a multiplier 4, and the synthesized directivity is formed. The correcting device 5 outputs the correcting value signal for the decrease in level based on the oscillation data from the detector 6. The multiplier 4 corrects the decrease in level caused by the bearings deflected from the front of each fan beam by multiplication and outputs the result.