ON THE APPLICABILITY OF FAST DIGITAL BEAM FORMING METHOD FOR SONAR SYSTEMS WITH COMPLEX SIGNALS

This work belongs to the field of hydroacoustics, namely problem digitalbeamforming based on spatial fast Fourier transform (FFT) in a multibeam echo sounder(MLS) with baseband digital signal processing. The applicability FFT-based beamformingwhen using relatively broadband signals is considered. main attention paid MLSwith static beam pattern, at same time, obtained results are also applicable rangingsystems that provide dynamic control. aim study establish relatio nshipbetween relative width spectrum and level channelof MLS given maximum steering. A qualitative condition for applicabilityof beamforming probing bandwidth isdetermined. An analytical expression linking attenuation coefficient spatialchannel following receiver characteristics was obtained: number ofelements linear equidistant antenna array, distance between array elements, beamsteering, correlation function complex envelope signal, window functionfor weighting matched filter response spectral domain. Presented can be usefulin designing sounders, providing high resolution both range angularcoordinates.