Key Technology Research Of High Precision Time Measurement Based On PXIe

Time is the most basic physical quantity, and high precision time measurement has been widely used in biomedical imaging, laser ranging and high energy physics experiments, etc. The PXIe bus, as a PCIe bus extension in the field of instrument, is a new industrial technology bus, which has the characteristics of high bandwidth,miniaturization, high modular instrument integrated and greatly enhance the transmission performance of the system in industrial technology application.This thesis discussed several popular time digital converter (TDC) methods in detail. In order to meet the requirements of all kinds of high energy physics scientific experiments, to measure the time measurement system of high accuracy,multi-channel and high transmission,I have designed a multi-channel high precision TDC measurement system based on PXIe bus. The main research work is as follows:(1)Finished the high precision time measurement module design of product level PXIe bus. Including system design, 32 channels front-end conditioning and high precision time measurement circuit design, process design and structural design.(2)Achieved the FPGA control logic of high precision time measurement system.Including the JTAG configuration module,control readout module, cache module, etc.And set up the subsystem that the PXIe hard core as the core achieved DMA, RAM,SDRAM, read-write and HPTDC JTAG configuration and data transmission control.(3)Finished the design of high precision time measurement System software in Linux environment. Including PXIe driver, user interface based on QT, function configuration, time data acquisition and off-line calibration.(4)Finished the time measurement precision test of the high precision time measurement system,and the code density is modified,which makes the measurement accuracy of the 32 channels mode better than 90ps, 8 channels mode is better than 22ps. After the PXIe transmission performance test, and the result show that the channel transmission rate as high as 1.2Gbps of PXIe1.1 X1.The high precision time measurement system in this paper has the characteristics of high density, high precision, high transmission rate, applied in all kinds of scientific experiments that needs of high precision time measurement and can be direct produced, reflects the value of practical application.