Systems and methods of sparse orthogonal diverging wave ultrasound imaging

An ultrasound imaging system comprising:

• an ultrasound array comprising a plurality of ultrasound array elements;
• control and processing circuitry operably connected to said plurality of ultrasound array elements, said control and processing circuitry being configured for performing the steps of:
• controlling the ultrasound array to sequentially transmit a plurality of unfocused ultrasound waves such that each unfocused ultrasound wave is encoded by a respective row of an invertible orthogonal matrix, wherein only a selected subset of rows of the invertible orthogonal matrix is employed to encode the unfocused ultrasound waves, such that the unfocused ultrasound waves are sparsely encoded;
• processing sets of receive signals received by the ultrasound array, wherein each set of receive signals is associated with transmission of a respective unfocused wave, by:
• decoding the sets of receive signals to obtain a plurality of sets of decoded receive signals such that each set of decoded receive signals is associated with insonification via a subset of the ultrasound array elements;
• and
• performing synthetic aperture beamforming on the plurality of sets of decoded receive signals to generate an ultrasound image.