Pulse-compression ghost imaging lidar via coherent detection

Abstract

Ghost imaging (GI) lidar, as a novel remote sensing technique, has been receiving increasing interest in recent years. By combining pulse-compression technique and coherent detection with GI, we propose a new lidar system called pulse-compression GI lidar. Our analytical results, which are backed up by numerical simulations, demonstrate that pulse-compression GI lidar can obtain the target's spatial intensity distribution, range and moving velocity. Compared with conventional pulsed GI lidar system, pulse-compression GI lidar, without decreasing the range resolution, is easy to obtain high single pulse energy with the use of a long pulse, and the mechanism of coherent detection can eliminate the influence of the stray light, which can dramatically improve the detection sensitivity and detection range.

Improving the Imaging Quality of Ghost Imaging Lidar via Sparsity Constraint by Time-Resolved Technique

“…Compared with the 2D GISC lidar, the 3D GISC lidar can not only obtain an image with a better SNR in the same random measurement number, but also achieve the scene's surface 3D image, which is much more advantageous in capturing the characteristics of the targets and has recently attracted increasing attention in remote sensing [18,19,26,27]. As an application in remote sensing, the 3D GISC lidar requires high time resolution and a spatial light diffuser with a high damage threshold.…”

“…For the former, we usually use a short narrow pulsed laser to illuminate the scene and measure the scene's signals with a wide-bandwidth single-pixel detector [18,19,26]. A recent report on pulse-compression GI lidar via coherent detection demonstrates that high depth resolution can also be obtained by using a long pulsed laser and low-bandwidth single-pixel detectors [27]. For the latter requirement, some spatial light diffusers, such as rotating ground glass disks, digital micro-mirror devices, and spatial light modulators, are used to modulate the spatial information of the light field in a GISC system [11,12,18,22,23,26,28].…”

Performance analysis of ghost imaging lidar in background light environment

“…Rectt∕T chirp , where s chirp t is a chirped-AM waveform with bandwidth B chirp and duration T B T C T chirp , and m is the modulation depth [14,15]. To obtain equivalent range resolution, we set B chirp 1∕T A .…”

“…Ghost imaging (GI) is a novel non-scanning imaging method to obtain a target's image with a single-pixel bucket detector [1][2][3][4][5][6]. Due to its capacity for high detection sensitivity, GI has aroused increasing interest in remote sensing, and a new imaging lidar system called GI lidar has gradually developed [7][8][9][10][11][12][13][14][15]. Up to now, there have been three types of three-dimensional GI lidars, namely narrow pulsed GI lidar, heterodyne GI lidar, and pulse-compression GI lidar via coherent detection [12][13][14][15].…”

“…However, similar to narrow pulsed GI lidar, heterodyne GI lidar uses a direct light-detection mechanism, which leads to a shorter detection distance because the laser's power is relatively low compared with narrow pulsed GI lidar. Pulse-compression GI lidar via coherent detection shares similar spatiotemporal light with heterodyne GI lidar, but its detection mechanism is based on coherent detection [15]. Pulse compression gives this lidar high-range resolution, long detection range, and insensitivity to stray light.…”