Deqi Cui

Spectral calibration method for all-reflected Fourier transform imaging spectrometer

All-Reflected Fourier Transform Imaging Spectrometer (ARFTIS) is a novel type of instrument based on Fourier transform spectroscopy. ARFTIS will offer high luminous flux and high spectral resolution, well suited to remote sensing with low energy. But there is nearly not any method of convenient spectrum calibration for this kind of instrument. In this paper, we analyze the spectrum calibration principle of ARFTIS and the cause of the calibration error. We reached the result that the calibration error is getting bigger with the increase of spectrum peak wavelength of the calibration light. By these we develop three convenient spectrum calibration methods used in Visible/Near-Infrared waveband, which are the Monochromatic Method, the Average Method and the Weighted Average Method respectively. We apply these methods to ARFTIS calibrate experiment. According to the experiment results, The Monochromatic Method can calibrate by using only one group of data, but with a little lower calibration precision. However the Weighted Average Method can provide a higher calibration precision than the other two methods. So, the Monochromatic method and the Weighted Average Method both have good application value for ARFTIS calibration.

Study of ARFTIS reconstruction model on GPU

There are huge calculations on reconstruct processing of all-reflective Fourier Transform Imaging Spectrometer (ARFTIS) data. Common algorithms often take long processing time. The Common Unified Device Architecture (CUDA) is a fundamentally new programming approach making use of the unified shader design of the most current Graphics Processing Units (GPUs) from NVIDIA. We research GPU develop platform and compare with CPU algorithmic structure. The results show that the CUDA may accelerate multiplications and additions computing significantly, that are the great mass of ARFTIS reconstruction. The CUDA programming interface allows implementing an algorithm using standard C language. Farther, we give some suggestions to optimize reconstruction algorithms on GPU.

Fast ARFTIS reconstruction algorithms using CUDA

In order to realize the fast reconstruction processing of all-reflective Fourier Transform Imaging Spectrometer (ARFTIS) data, the authors implement reconstruction algorithms on GPU using Compute Unified Device Architecture (CUDA). We use both CUDA 1DFFT library and customization CUDA parallel kernel to accelerate the spectrum reconstruction processing of ARFTIS. The results show that the CUDA can drive hundreds of processing elements (‘manycore’ processors) of GPU hardware and can enhance the efficiency of spectrum reconstruction processing significantly. Farther, computer with CUDA graphic cards will implement real-time data reconstruction of ARFTIS alone.

Realization of Fourier transform imaging spectrometer based on all-reflective optics

We present our latest research development of the all-reflective Fourier transform imaging spectrometer based on the principle of wavefront-splitting interference. The optical configuration of this system includes a set of Fresnels double mirrors and a number of other reflective telescopes or mirrors. The major advantages of this system includs higher optical throughput, larger spectral bandwidth, and less chromatic aberration as compared with conventinal chromatic-despersion imaging spectrometer . In this paper ,the optical principle and the prototype device of our system are introduced, and the latest experimental results from our prototype device are presented.

Novel all-reflective Fourier transform imaging spectrometer based on Fresnel double-mirror

In order to develop new technology during the spaceborne remote sensing mission, we introduce a novel all-reflective Fourier Transform Imaging Spectrometer(FTIS) based on Fresenel Double Mirror (FDM). Using all reflective parts, the system can work in visible and infrared waveband. Besides, the novel optical configuration which is involved can lead to the characters of the high spatial, spectral resolution and large field of view. The basic performance of the system was analyzed based on the test results.

Multispectral imaging utilizing LCTF technology for plant disease detection

The aim of this paper is to pave the way for the establishment of analysis of the lights reflected from the leafs surface as an analytical method of plant disease. An imaging LCTF spectrometer that covers a visible light with 400-720 nm wavelength bands has been developed. This paper first outlines the structure of imaging LCTF spectrometer, including their operational principles and construction. Next, various spectral images acquired using the LCTF spectrometer in laboratory environment experiments to measure spectral characteristics of rays reflected from cucumber leaves surfaces that are infected by different germs are analyzed. Then, the results of the experiments conducted using the imaging spectrometer are shown, including the analyzed relative radiance of rays reflected from the plants, and spectral images acquired at various wavelengths. These experimental results demonstrate clearly that rays reflected from plant contaminated by different disease germs have different spectral properties.

Parallel cube reconstruction of HSI based on openMP

Hyper Spectral Imager (HSI) on ‘HJ-17rsquo; Chinese satellite is a kind of Fourier Transform imaging spectrometer (FTIS). In order to realize the fast reconstruction processing of HSI data, the authors designed the fast reconstruction algorithms using OpenMP parallel computing. The results show that the framework based on OpenMP can use the multi-core CPU hardware resources competently and can enhance the efficiency of spectrum reconstruction processing significantly. It has already been used on the data processing service of HSI at China Center for Resource Satellite Data and Applications successfully. If this framework is applied to more cores workstation in parallel computing, a single computer to implement real-time data reconstruction of FTIS will be possible.

Simultaneous acquisition of hyper-spectral image using the computed tomography imaging interferometer

In this paper, we introduce a new approach of simultaneous acquisition of hyper-spectral image by means of using Computed Tomography Imaging Interferometer. Detecting rapidly varying targets both spatially and spectrally using imaging spectrometer is an international phenomenon in remote sensing in recent years and worthwhile in many domains such as pollution inspection and biochemical arms detection. Computed Tomography Imaging Interferometer (CTII) we put forward previously is a kind of imaging spectrometer with merits of high resolution, high throughout and high signal-to-noise rate. In our current work, some transmogrifications have been brought into the existed model of CTII. More channels are constructed in the new type of CTII-Simultaneous CTII (SiCTII). The rotation system in each channel is made irrotianal. Snapshot can be brought in the acquisition by means of opening and closing channels simultaneously. The Algebraic Reconstruction Technique (ART) and Artificial Neural Network (ANN) are considered in the image reconstruction. Referring to the characteristics of SiCTII, a conclusion can be made that SiCTII is a kind of imaging spectrometer for rapid acquisition and can be applied in the instances, in which the spatial resolution is not highly demanded and rapid data acquisition is demanded.