Phase-laser ranging system based on digital signal processing for optoelectronics theodolite application

In order to meet requirement of high accurate ranging, the laser ranging system is designed for optoelectronics theodolite application by this paper, based on digital signal processing. Variable modulating method is used to solve the antinomy between the measuring range and accuracy. Frequency mixing is adopted to reduce the frequency of the signal, which can lower the requirement for hardware. The high ranging accuracy is achieved by way of Fast Fourier Transform (FFT) using digital signal processor and error correcting factor. Experiment results indicate that using digital signal processing method can reduce the influence of surroundings and hardware system, and obtain high ranging accuracy.