With an understanding of the discrete building blocks, active probes with in-probe electronics and the associated system partitioning will be studied, with use cases in SNR enhancement and the realization of 3D probes and wearables. The use of Application-Specific Integrated Circuits (ASICs) and the integration of such ASICs with ultrasound transducer arrays will be discussed. Approaches to realizing in-probe transmit and receive circuitry will be introduced. Multiplexing, sub-array beamforming and in-probe digitization will be discussed as approaches to realizing the channel-count reduction that is crucial for high-element-count 3D probes.
The course concludes by exploring ultrasound system design in context of passive probes with separate AFEs and active probes with in-probe electronics. The challenges and techniques for data acquisition (both multiplexed and full-channel), storage and transfer will be discussed. Beamformer implementations will be introduced, with emphasis on delay-and-sum. Techniques for data post-processing for B-mode and Doppler modes will be covered. Finally, communication with active probes and the handling of pre-beamformed data will be discussed.
