The Design Of Laser Doppler Signal Acquisition System

First, the development at home and abroad, the research trend and the conventional measuring method of laser doppler technique for measuring velocity are introduced in this paper. Second, based on the basic theories and the key technology of laser doppler measurement, we combines differential optical path with designing the software and the hardware of the signal acquisition system. And measuring speed of moving object was carried out. The laser doppler measurement was optimized, too. Finally, the experiment errors were analyzed.According to the requirement of the project, a differential optical path was built. CY7C68013A and AD7568 were chosen as core chip. And the circuit of data acquisition system was designed by combining optical-electronic sensor, expanding external EEPROM and considering anti-interference. The host mode GPIF was adopted to design the interface of CY7C68013A from CYPRESS. Through designing the firmware program, driver program and application program, especially GPIF waveform, the doppler signal was captured and processed. The synchronous data acquisition and transmission with high speed was carried out, which was based on USB2.0. Lastly, the experiment errors were discussed and some improvements were put forward.