Characterization of InGaAs self-mixing detectors for chirp amplitude-modulated ladar (CAML)

The U.S. Army Research Laboratory (ARL) has developed a number of near-infrared, prototype laser detection and ranging (LADAR) Systems based on the chirp, amplitude-modulated LADAR (CAML) architecture. The use of self-mixing detectors in the receiver, that have the ability to internally detect and down-convert modulated optical signals, have significantly simplified the LADAR design. Recently, ARL has designed and fabricated single-pixel, self-mixing, InGaAs-based, metal-semiconductor-metal detectors to extend the LADAR operating wavelength to 1.55 mum and is currently in the process of designing linear arrays of such detectors. This paper presents fundamental detector characterization measurements of the new 1.55 mum detectors in the CAML architecture and some insights on the design of 1.55 mum linear arrays.