Research On Improving Measurement Accuracy And Signal To Noise Ratio Of Laser Range Finder

This thesis mainly study in two two aspects of the pulse laser distance measurement system that one is to improve the measurement precision and the other is to increase the signal to noise ratio of laser echo pulse.In the part of the measurement precision, it is to sum up many kinds of time interval measurement method and focus on studying in the time-to-digital-converters TDC-GP2.And it designs a high-precision time interval measurement circuit in accordance with the characteristics of TDC-GP2. In the part of increasing the signal to noise ratio of the receiving system, the thesis introduces a new digital receiver system which are formed with ultra-high-speed A / D converter in sampling rate of 2Gsps and FPGA. TO convert laser pulse-echo signals to digital signals in using A / D and then using digital signal processing to increas e signal to noise ratio of laser pulse-echo signals.The algorithms are Haar wavelet transform domain LMS and integer 5/3 wavelet transform, which are using to eliminate system noise. Making use of MATLAB, DSP Builder, and other related EDA tools, FPGA can realise two algorithms. According to the previous presentation, the thesis develop two new digital pulse laser distance measurement system.