Streak Tube Imaging Lidar Research Articles

条纹管成像激光雷达距离分辨率

条纹管成像激光雷达距离分辨率

Signal-to-noise performance analysis of streak tube imaging lidar systems I Cascaded model

Streak tube imaging lidar (STIL) is an active imaging system using a pulsed laser transmitter and a streak tube receiver to produce 3D range and intensity imagery. The STIL has recently attracted a great deal of interest and attention due to its advantages of wide azimuth field-of-view, high range and angle resolution, and high frame rate. This work investigates the signal-to-noise performance of STIL systems. A theoretical model for characterizing the signal-to-noise performance of the STIL system with an internal or external intensified streak tube receiver is presented, based on the linear cascaded systems theory of signal and noise propagation. The STIL system is decomposed into a series of cascaded imaging chains whose signal and noise transfer properties are described by the general (or the spatial-frequency dependent) noise factors (NFs). Expressions for the general NFs of the cascaded chains (or the main components) in the STIL system are derived. The work presented here is useful for the design and evaluation of STIL systems.

Signal-to-noise performance analysis of streak tube imaging lidar systems II Theoretical analysis and discussion

In the preceding paper (referred to here as paper I), we presented a general signal-to-noise performance analysis of a streak tube imaging lidar (STIL) system within the framework of linear cascaded systems theory. A cascaded model is proposed for characterizing the signal-to-noise performance of a STIL system with an internal or external intensified streak tube receiver. The STIL system can be decomposed into a series of cascaded imaging chains whose signal and noise transfer properties are described by the general (or the spatial-frequency dependent) noise factors (NFs). Equations for the general NFs of the cascaded chains (or the main components) in the STIL system are derived. This work investigates the signal-to-noise performance of an external intensified STIL system. The implementation of the cascaded model for predicting and evaluating the signal-to-noise performance of the external intensified STIL system is described. Some factors that limit the signal-to-noise performance of the external intensified STIL system are analyzed and discussed.

Low-contrast target detection using polarized Streak Tube Imaging Lidar

Streak Tube Imaging Lidar (STIL) is provided with the characteristics of high resolution, high detection sensitivity, and wide field of view (FOV). It is a new type laser radar, and has actual application. For the low-contrast condition, image segment becomes difficult to STIL, which will influence on the detection/recognizing rate. In order to resolve the problem, a new polarized STIL imaging system is presented. Its structure is designed, which is included a polarizer and a Wollaston prism to the transmitting and receiving system, respectively. The polarized STIL can simultaneously collect the two polarization images. Through image processing and computing, the intensity and DOP images with high resolution are obtained, which can provide the rich information of targets. The far distance imaging experiments that the part target is hidden in the clutter are carried out. The results state that the polarization images have high-contrast, and it is easy to segment target from the background.

A multiple-slit streak tube imaging lidar and its detection ability analysis by flash lidar equation

Lidar detectable range, usually affected by detection unit sensitivity, operating mode and visibility, is a critical factor in system design and application. Classical lidar equation is derived based on lidar system with single detector, which is suitable for scanner lidar. In this paper we discussed the lidar equation for flash lidar based on flat-panel detector, and derived a more suitable lidar equation for flash lidar. Using the lidar equation derived, we simulated the range performance of a multiple-slit streak tube imaging lidar developed by our laboratory, and then conducted an out-door experiment to evaluate the system performance.

条纹管成像激光雷达条纹数据提取算法

条纹管成像激光雷达条纹数据提取算法

The Research of 3D Reconstruction Based on Streak Tube Imaging Lidar

The streak tube imaging lidar (STIL) system is a new 3D imaging technology that can obtain a complete frame image of the target with only one laser pulse and it has many advantages such as high frame rate, big field of view and so on over the scanning-mechanism system. The principle of the experiment will be introduced firstly and the pre-process of the data will be simply discussed, such as correction of image distortion, the noise filter and image enhancement, data segmentation and so on. All the methods to the above data pre-process are specially adopted for the STIL system. The range of the target, the time of the photoelectron flight and the range of the target image on the phosphor screen have a linear relationship and it will be proved; according this, a mathematical model to reconstruct the 3D image is put forward and the algorithm to calculate the relative range of the target is confirmed. Based on the model and the algorithm, a program in the VC++ and matlab environment to analyze the lidar data, reconstruct and display the 3D image of the target is compiled. The result verifies the model and the algorithm effective.

大视场条纹管激光雷达设计及成像实验研究

大视场条纹管激光雷达设计及成像实验研究

条纹管激光成像雷达目标重构算法

条纹管激光成像雷达目标重构算法

Analysis of detectable range of multiple-slit streak tube imaging lidar

Multiple-slit streak tube imaging lidar is a promising flash imaging system. Its detectable range, affected by the detection of the unit sensitivity, operating mode, and visibility, are critical factors for the system design and applications. In order to discuss the lidar range measurement performance, a lidar equation based on the Lambert law is analyzed, and the relationship between the lidar detectable range and the emission power is simulated at different levels of visibility; the result shows that the detectable range of lidar developed in our laboratory reaches 2,500 m for a 23 km visibility. Outfield experiments were carried out to evaluate the system performance; a clear stripe image for a target located 1386 m away was gained under the condition of 15 km visibility. Finally, parameters that affect the lidar detectable range are discussed, and relevant methods to improve the lidar performance are proposed.

4-D image reconstruction for Streak Tube Imaging Lidar

The Streak Tube Imaging Lidar (STIL) which is the flash laser radar is developed in recently years. It can output the 4-D image (3-D range image + 1-D intensity image). The core part of STIL is the streak tube, which is a line array detector. STIL can directly collect the image of returned light pulse, and consequently, it can’t output the 4-D target image. In the paper, the peak detection as the reconstruction algorithm is used to reconstruct the multiple streak tube images, and the clear 4-D target images are obtained. The outdoor imaging experiments are completed for the far distance buildings. The reconstruction for the multiple streak tube images is finished, and the results state that the peak detection algorithm can output the high-resolution 4-D target images.

多狭缝条纹管激光雷达系统设计及实验研究

多狭缝条纹管激光雷达系统设计及实验研究

条纹管激光成像雷达数据处理系统分析与设计

条纹管激光成像雷达数据处理系统分析与设计