Laser diode transmitter for laser radar based on FM ranging principles

摘要

The purpose of this paper is to present the prototype of the laser diode transmitter for the laser radar based on frequency-modulated (FM) ranging principles. It belongs to the time-of-flight measurement category. In this case, the time-of-flight is converted to a beat frequency proportional to the range to be measured. This conversion is realized with intensity modulation of the laser power by a linear FM continuous wave. FM ranging theory and the principle of operation are described to show the application of FM radar principles in laser radar. The design of laser diode illuminator and the key techniques in the transmitter are discussed, including the generation technique of the wideband radio-frequency (RF) chirp signal, design of the transmitter module and the laser beam collimation optics. The possible factors that may limit the performance the laser radar system are discussed.