Three dimensional imaging laser radar system for short-range target detection and identification

Compared with other imaging approaches, high resolution angle-angle-range imagery provided by the three dimensional imaging laser radar increases probability of target identification. Based on scannerless pulsed time-of-flight method, this paper presents breadboard laser radar for proof-of-principle. A laser transmitter using laser diode flood illuminates a target area with a relatively short pulse, then a receiver collects the returned energy on a 4x4 PIN diode array where each pixel measures range respectively. Each of 16 channels consists of a TIA, main amplifier, timing discriminator and a TDC channel. A processor based on microcontroller processes the output result of all pixels from two TDCs, then transfers final range data to laptop for visualization. Here we present some preliminary intensity images of target acquired through indoor experiments. Through these results, the feasibility of direct-detection imaging laser radar for short-range target identification has been proved. Meanwhile, further development of this system is discussed.