LIDAR echo emulator

Abstract

The LIDAR Echo Emulator (LEE) emulates the returned signals from a Lidar system. As the return signal of a Lidar system depends on the target, this implies the capability of shaping the laser’s returns. In brief, a long echo corresponds to a natural or diffusive object (canopy, clouds) and short echoes to a complex thing like roofs, ground, etc. Such signals must be simulated to study and validate new detectors and detection systems without developing/procuring the entire Lidar system.

LEE consists of pulse shaping electronics to drive the lasers independently for each echo and an internal detection system to monitor the pulses. The short echoes can range from 5 ns to hundreds of ns and the long echoes from 1 μs up to hundreds of μs. The repetition rates of the developed emulator are from 100 Hz to 10 kHz, with a limitation that the most extended pulse does not exceed 10% of the duty cycle.

The power difference between both echoes can be set and is as high as 60 dB. The dynamics of the echoes are better than 50 dB within the eight ns in the rising/falling edge of the pulse (echo). The output power can be tuned using variable attenuators, giving a range of the incoming echoes from -35 dBm to -100 dBm. The LEE can also emulate multiple returns with the dynamics above.

In this paper, we will present a LEE developed for HgCdTe characterization at 1064 nm. First, we will offer the requirements of the characterization setup and possible approaches in section 2. Then in section 3, we will show the design and realization. In section 4, we will present obtained results concerning performance, and we will summarize the work in section 5.

Second Equipment developed

Development of a NIR-VIS-UV lidar echo emulator

Co-Authors:

Alvaro Machon
Monica Rodriguez Cortina
Alejandro Lopez Moya