Emulation Technique of Multiple Overlapped Return Echoes of a Spatial LIDAR With 100-dB Dynamic Resolution

A new compact and cost-effective instrument for dynamic characterization of ultrawide dynamic range photodetectors is presented. The instrument is an optical pulse shaper (OPS) which has been developed as a LIDAR echo emulator (LEE). It uses a single laser diode at 1064 nm, its corresponding driver, and arbitrary waveform generator (AWG), to generate two overlapping LIDAR echoes (short and long). A 60-dB difference between the maxima of the echoes is achieved with a full dynamic range of 100 dB. The LEE is designed to make possible the characterization of the detection chain of a spatial LIDAR which uses a high-dynamic range HgCdTe avalanche photodetector (APD) but can be reprogrammed to emulate any high-dynamic range terrestrial or space LIDAR application.