Abstract

The transmitter waveform choices for direct-and heterodyne-detection CO₂ laser rangefinders are considered. For direct detection, signal-to-noise arguments favor a short-pulse system for energy economy, and the TEA laser is a natural transmitter choice. For heterodyne detection, the same motivation to short pulses does not apply; although frequency-stable short pulse sources provide a feasible avenue, a wide range of possibilities opens when modern microwave signal-processing technology is applied using acoustooptic modulation of a cw source, and range accuracy is attained even with long pulses by frequency modulation.

© 1981 Optical Society of America