Ultrasound beamforming system and method based on analog random access memory array

An Analog Store Digital Read ultrasound beamformer for an ultrasound imaging system comprising:

• An ultrasonic array formed of individual ultrasonic array elements configured for transmission and receiving, wherein the individual array elements are grouped into individual channels, wherein each channel comprises at least one array element;
• A Receiving input signal control circuitry for creating receiving input signals for each channel from inputs received from each array element of the channel;
• A plurality of banks of sample-hold cells with each bank of sample-hold cells associated with one channel, wherein the beamformer is configured for sampling each receiving input signal for each channel at a sampling rate and storing the sampled data in one bank of sample-hold cells which are associated with that channel, wherein the bank of sample-hold cells form an analog random access memory for the associated sampled receiving input signal;
• A beamforming processor configured for selecting at least one sample-hold cell data from at least one channel for each beamforming instance in accordance with a beamforming algorithm;
• An analog summation element for summing all of the selected sample-hold cell data from each channel for each beamforming instance and forming an analog beamformed received signal for the beamforming instance;
• and
• An Analog-to-Digital converter for digitizing the analog beamformed received signal.

An Analog Store Digital Read ultrasound beamforming method for an ultrasound imaging system comprising the steps of:

• i) Providing an ultrasonic array formed of individual ultrasonic array elements configured for transmission and receiving;
• ii) Dividing the individual array elements into individual channels, wherein each channel comprises at least one array element;
• iii) Creating a receiving input signal for each channel from inputs received from each array element of the channel;
• iv) Sampling each receiving input signal for each channel at a sampling rate and storing the sampled data in a bank of memory cells, wherein the bank of memory cells form an analog random access memory, wherein one of
• a) the present sample from each channel participating in this beamforming instance is added to at least one memory cell with addresses thereof defined by the beamforming algorithm for this particular time instance, wherein each memory cell is associated with a sample clock time instance, and wherein each memory cell participating in the beamforming instance sums the selected samples from plurality of channels selected by the beamforming algorithm forming an analog beamformed received signal sample for the beamforming instance, or
• b) the analog random access memory has at least one row per channel and the number of columns being equal or larger the number produced by multiplying the sampling rate to maximum delay needed to correct, wherein the instantaneous sample from each channel participating in this beamforming instance is added to at least one memory cell with addresses thereof defined by the beamforming algorithm for this particular time instance, wherein each memory cell in the row is associated with a sample clock time instance each memory cell in the column in associated with the scan line, and wherein each memory cell participating in the beamforming instance sums the selected samples from plurality of channels selected by the beamforming algorithm forming an analog beamformed received signal sample for the beamforming instance;
• and
• vii) Digitizing the analog beamformed received signal sample.