A pipelined beamforming delay calculation architecture in ultrasound imaging system

In the beamformers of modern digital ultrasound imaging system, to avoid storing amount of precalculated parameters, real time delay calculation has to be used. This paper describes the design and implementation of a calculator of beamforming delay parameters, which based on pipelined Coordinate Rotation Digital Computer (CORDIC) architecture and 2-level carry look ahead (CLA) adder. High computational speed is achieved while computational logic is saved. The calculator is used in a 128-channel ultrasound system with sampling frequency of 40 MHz and beamforming delay update rate of 10 MHz. Being synthesized for a Virtex-5 XC5VLX110T FPGA, the maximum clock frequency is 351.494MHz, and only 8 calculators are needed in two-receive-beam system.