Real-time phased array imaging using digital beam forming and autonomous channel control

The authors designed and constructed a real-time phased-array imaging system for medical applications based on the principles of digital beam formation and autonomous channel control. The system is capable of high-precision steering, dynamic apodization, dynamic focusing, and highly accurate beamforming using sampling rates close to the Nyquist rate over the medical diagnostic frequency range. All controls and signal processing needed for a single channel of the array imager have been integrated into a single custom VLSI circuit. The authors describe the basic principles embodied in this chip