A class of planar arrays having broad frequency range applications for source location, source imaging or target illumination with projected beams is described in this disclosure. The non-redundant arrays are circularly symmetric and made up of a plurality of sensing and/or transmitting elements arranged so as to substantially eliminate grating lobes for a broad range of frequencies. Signals received from or transmitted to the elements are appropriately phased to control the beam of the array.

Circularly symmetric, zero redundancy, planar array having broad frequency range applications

An array transducer ultrasound beamformer (300) includes a plurality of processing channels, one for each active element of the transducer array (300). Each channel includes a digitizing unit (330) for converting the received signal to digital samples and a time multiplexed delay unit (340) for producing a primary stream of delayed TDM samples corresponding to one or more beams. Within each channel, the primary stream of delayed TDM samples is demultiplexed (360) in order to separate the stream in a plurality of secondary streams of delayed TDM samples, wherein each of the secondary streams corresponds to a portion of a beam or a single beam.

Digital ultrasound beamformer

A beamforming method and apparatus utilizing a plurality of sensing elements which are free to take up random positions Each sensing element generates output signals in response to sensed radiation The signals are fed to a data process or which generates Fourier frequency components of each output signal and selects a Fourier frequency component for each given radiation frequency to form a group of frequency components The data processor performs a spatial convolution, interpolation and spatial Fourier transform followed by an averaging procedure in order to obtain an output signal which is indicative of the far field radiation power as a function of angle thus providing the desired beamforming information

Method and apparatus for random array beamforming

The sonar array post processor employs an adaptive processing, known as matched beam processing, in the beam domain which takes analog or digital conventional beamforming outputs from a sonar array, multiplies them by a set of adaptive weighting coefficients and produces a new set of beams. The new output beam of highest intensity yields the ideal maximum signal gain and correct target bearing. Continuous target tracking provided by the sonar array post processor in the endfire direction of a horizontal line array minimizes the towing ships maneuvers and for, a bottom mounted surveillance system, a smaller number of arrays are required.

Sonar array post processor

L'invention concerne les dispositifs permettant de former des voies dans les systemes d'imagerie acoustique tels que les sonars ou les echographes medicaux. Elle consiste dans un tel systeme a utiliser par capteur de l'antenne comme convertisseur analogique-digital un modulateur du type SIGMA/DELTA (102) suivi d'une ligne a retard a 1 bit (103). Elle permet d'obtenir un dispositif de tres petite taille pouvant se loger directement dans l'antenne, une sonde medicale par exemple.

Dispositif de formation de voies pour système d'imagerie acoustique.

This invention is a hydrophone (element) sited beamformer which is coupled to an array cable of a horizontal line array. A hydrophone-sited beamformer is coupled to each hydrophone in the array. The element-sited beamformer directly forms beams from the data detected by the hydrophones by delaying and selecting some of the hydrophone detected data and summing this data with the proper shading value.

Robert L. Maynard

Papers

Element-sited beamformer