2C-4 A 64-Channel Beamformer for 50 MHz Linear Arrays

This paper describes the design and implementation of a 64-channel beamformer for a 50 MHz linear array for use in medical imaging. The results for a series of theoretical models comparing various beamforming algorithms are given. The final algorithm is a compromise solution, applying a simple linear interpolation algorithm to a data set acquired using 4x interleaved sampling. This allows for 12 bit, 200 MS/s performance with a 50 MS/s ADC. This algorithm has been implemented on a Virtex 4 FPGA using a commercially available applications board featuring onboard SDRAM, oscillator, and parallel and serial communications. This board was tested with ideal data, as well as with an 8-channel analog board. There was excellent agreement between the hardware and computer simulation results.