Design And Implementation Of Ddr2 Interface Based On Fpga In 3d Ct Reconstruction

Computer Tomography has developed rapidly in the last 20 years, and the result is great. It is widely used in many fields now, such as medical diagnostics, non-destructive industrial testing and radar. Katsevich presented an exact 3D image reconstruction algorithm in 2002. This algorithm does not need the detecting board whose shape is special and can deal with the edge of reconstructed object and short object; moreover, the data needed in backprojection of Katsevich algorithm is calculated by Hilbert transform, which is simple. So, Katsevich algorithm has become a hot spot of research and development.Katsevich algorithm is complicated and needs a huge amount of data in medical 3D cone-beam CT reconstruction system. So, the system needs high-powered equipment, whose function is data access, and data path.This thesis mainly consists of three parts. Firstly, improve the DDR2 Controller code generated by CORE Generator to achieve data access of DDR2 SDRAM, which is on the outside of board.Secondly, design a part of data path to meet the data-squence need of derivation, interpolation and Hilbert transform in Katsevich algorithm and save hardware resource reasonably.Finally, compile the test modules in the Modelsim against DDR2 Controller simulation, and design hardware implementation under the environment of ISE after verifying its function correctly; compile the test modules in the Modelsim against the part of data-path module and analyze the timing.In the thesis, design and implementation of DDR2 interface based on FPGA in 3D cone-beam CT reconstruction is of practical signality. This thesis utilize fast data access of DDR2 and provide a method to solve speed problem of data transmission in 3D cone-beam CT reconstruction and opportunity to achieve real-time reconstruction of the image as a whole.