Effects of speckle on the range precision of a scanning lidar.
The dynamic speckle generated by a scanning lidar is a major contributor to the range precision for long transmitter pulses, such as those for a linear frequency-modulation-chirp waveform. The linear portion of the speckle-phase variations is automatically compensated, and the range precision is significantly improved, when an upchirp and downchirp pair is transmitted simultaneously, combined with a proper demodulation process. This concept was verified through a laboratory demonstration. The effect of speckle-amplitude variations on the compressed-pulse waveform is also investigated.
Wang
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Pruitt
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