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Primary Examiner—Marvin M. Lateel
Assistant Examiner—Ali M. Imam
Attorney, Agent, or Firm—Marvin Snyder; Douglas E.
Stoner
[57] ABSTRACT
In an ultrasound imaging system, a multiplexer connects a beamformer to a multi-row transducer array, where the array has more electrically independent transducer elements than the beamformer has channels, so as to provide dynamic selection and beamforming control ol multi-row apertures. The multiplexer allows the active aperture to be scanned along at least one axis of the array and allows the shape of the active aperture to be varied electronically. The multiplexer, which supports transmit and receive apertures appropriate for synthetic aperture beamforming, is of modular construction, enabling multiplexers appropriate for transducer arrays with various numbers of rows and columns of elements to be easily assembled from a standard set of parts. The multiplexer is physically designed as a passive backplane into which various switch cards can be plugged. The card connectors are arranged in two parallel columns. Traces from system channels are distributed on the backplane; coaxial leads from transducer elements are connected to the switch cards.
20 Claims, 12 Drawing Sheets
