Journals >Journal of Infrared and Millimeter Waves
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2019
Volume: 38 Issue 1
20 Article(s)
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Welcome to our new Editorial Board Members of the Journal of Infrared and Millimeter Waves at 60th anniversary of SITP and happy new year 2019
M.H. Zhang, H. Shen, Z.X. Li, X. Liu, and J.H. Chu
It is a great honor to introduce Prof. Dr. Weida Hu and Prof. Dr. Chaohai Du as our new Editorial Board Member of the Journal of Infrared and Millimeter Waves at 60th anniversary of the Shanghai Institute of Technical Physics (SITP) of the Chinese Academy of Sciences. SITP celebrated its 60th year of existence on OctobIt is a great honor to introduce Prof. Dr. Weida Hu and Prof. Dr. Chaohai Du as our new Editorial Board Member of the Journal of Infrared and Millimeter Waves at 60th anniversary of the Shanghai Institute of Technical Physics (SITP) of the Chinese Academy of Sciences. SITP celebrated its 60th year of existence on October 28, 2018, with a scientist and engineer academic conference to commemorate the six decades of its history, to honor the six decades that SITP has devoted to developing science and technology in frontier areas of infrared physics. SITP was cofounded by CAS and Fudan University on October 28, 1958 . SITP's primary research area is the application of infrared physics and optoelectronics technology with particular attention to new infrared photoelectric materials, devices and methods, etc. Journal of Infrared and Millimeter Waves(JIMW) is a non-profit journal which is fully funded and published by the SITP. The journal was first published in 1982. The Editorial Board of the Journal of Infrared and Millimeter Waves includes experts from all major fields within the infrared, millimeter and terahertz waves to cover the scope of the journal. As SITP turns 60, we invite Dr. Hu and Dr. Du to join the celebrations, be the new Editorial Board Members of JIMW and help us create a splendid future..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 1 (2019)
Atomic-Layer-Deposited ultrathin films of vanadium pentoxide crystalline nanoflakes with controllable thickness and optical band-gap
ZHANG Tian-Ning, WANG Shu-Xia, HUANG Tian-Tian, WEI Wei, CHEN Xin, and DAI Ning
Thin films of crystalline V2O5 nanoflakes were prepared through atomic layer deposition (ALD) process. The film thickness was verified to play a critical role in determining structural morphology, optical bandgap and Raman vibration of crystalline V2O5 thin films. Two optical bandgaps observed at about 2.8 eV and 2.4 eThin films of crystalline V2O5 nanoflakes were prepared through atomic layer deposition (ALD) process. The film thickness was verified to play a critical role in determining structural morphology, optical bandgap and Raman vibration of crystalline V2O5 thin films. Two optical bandgaps observed at about 2.8 eV and 2.4 eV result from two growth stages during ALD preparation. We expect that these results help to understand the growth control of ultrathin films and their functional devices..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 3 (2019)
Design method for triple conjugate optical system with good stray light control performance
YU Qing-Hua, XIAO Xi-Sheng, CHEN Fan-Sheng, and SUN Sheng-Li
Stray light control is an important technical indicator of an optical system’s performance. The stray light in infrared optical systems includes not only external stray light, but also the internal radiation stray light. The conventional initial system design method limited to an “object-image" conjugate relationsStray light control is an important technical indicator of an optical system’s performance. The stray light in infrared optical systems includes not only external stray light, but also the internal radiation stray light. The conventional initial system design method limited to an “object-image" conjugate relationship cannot properly take account of stray light. This paper presents a triple conjugate optical system design method for “object-image”, “object-intermediate real image” and “entrance pupil-exit pupil” triple conjugate relationships that minimizes the influences of internal and external stray light to provide good stray light control performance. With this method, an off-axis three-mirror anastigmatic infrared optical system with F/# = 4, linear field of view = 7°, point source transmission less than 5×10-4, and cold iris efficiency 96% was designed and imaged good pictures in orbit..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 8 (2019)
Design of a TE34,10 mode cylindrical cavity for MW level gyrotron
MA Guo-Wu, HU Lin-Lin, ZHUO Ting-Ting, SUN Di-Min, HUANG Yin-Hu, CHEN Hong-Bin, and MENG Fan-Bao
A cylindrical gyrotron cavity is designed and optimized with a high order mode TE34,10-to deliver an output power of megawatts level at 140 GHz. Analysis on mode competition indicates that the two adjacent modes TE33,10-and TE31,11+ involve in competition and cause significant decreasing of output power of TE34,10-. ToA cylindrical gyrotron cavity is designed and optimized with a high order mode TE34,10-to deliver an output power of megawatts level at 140 GHz. Analysis on mode competition indicates that the two adjacent modes TE33,10-and TE31,11+ involve in competition and cause significant decreasing of output power of TE34,10-. To suppress the competition hysteresis loops of TE31,11+ and TE33,10-with TE34,10-are calculated, which indicates TE34,10-can inhibit growth of the other two modes with decreasing magnetic field from its low efficiency single mode oscillation zone, while it turned out just the opposite with increasing magnetic field due to the earlier oscillation of the competitors. Based on the results, a multimode time-dependent calculation including 42 modes is carried out with magnetic field dropping from 5.59 T to 5.51 T, the results show that mode competition is successfully suppressed, the operation mode TE34,10-realizes stable single mode oscillation with an output power of 0.96 MW and an electron efficiency of 36.7% at 140 GHz..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 15 (2019)
Theoretical study on the far-infrared perfect absorbers with SU8 based multilayered metamaterial structure
HU Zhi-Ting, CHEN Ji-Wei, DU Lei, ZHU Yu-Fang, ZHANG Jia-Zhen, XU Huang, LIU Feng, and CHEN Gang
A theoretical study on the perfect absorbers working in the far-infrared region with SU8 based multiple-layer metamaterials has been demonstrated. The perfect absorbers consist of periodic array of metal particles, SU8 dielectric spacing layer and a thicker metallic bottom layer. Through the LC model and the finite eleA theoretical study on the perfect absorbers working in the far-infrared region with SU8 based multiple-layer metamaterials has been demonstrated. The perfect absorbers consist of periodic array of metal particles, SU8 dielectric spacing layer and a thicker metallic bottom layer. Through the LC model and the finite element numerical simulation methods, we studied the performance of the absorber. With finely tuned parameters, such like the thickness of the SU8 dielectric layers, the periodicity of the metal particles array, and the length of the metal particles, the near perfect absorption up to~100% at the wavelength range between 20 μm to 30 μm for far infrared can be achieved. Based on these results, further design for the double-resonator absorber has been provided. Dual band perfect absorption can be accurately and independently obtained by adjusting the particle size of the upper and the lower metal layers. Moreover, the wavelength of the perfect absorption is also almost independent of the incident angle. These phenomena can be attributed to the multiple reflections between the thick metallic bottom layer and metal particle layers separated by SU8 dielectric layer, which can also be explained using a LC model as the resonant absorption in the metal-dielectric-metal cavities..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 21 (2019)
Fundamental W-band InP DHBT-based voltage-controlled oscillator with wide tuning range and high output power
WANG Xi, YAO Hong-Fei, SU Yong-Bo, DING Wu-Chang, MUHAMMAD Asif, DING Peng, TONG Zhi-Hang, and JIN Zhi
A fundamental W-band voltage-controlled oscillator (VCO) featuring high output power and wide tuning range has been successfully designed. The VCO was fabricated utilizing 0.8 μm InP DHBT technology. The DHBT exhibits peak fT of 170 GHz and fmax of 250 GHz. The VCO core implemented a balanced Colpitts-type topology modA fundamental W-band voltage-controlled oscillator (VCO) featuring high output power and wide tuning range has been successfully designed. The VCO was fabricated utilizing 0.8 μm InP DHBT technology. The DHBT exhibits peak fT of 170 GHz and fmax of 250 GHz. The VCO core implemented a balanced Colpitts-type topology modified for high-frequency application. An additional buffer amplifier stage was connected with the core to further boost output power as well as eliminate the load pulling effect. The DHBT base-collector P-N junction at reverse bias was chosen as a varactor diode to realize a wide frequency tuning. The measured results demonstrate that the oscillation frequency of the proposed VCO can be tuned between 81~97.3 GHz, which is a relative tuning bandwidth of 18.3 %. Over this frequency range the oscillator has a maximum output power of 10.2 dBm, and the power variation is less than 3.5 dB. A phase noise of -88 dBc/Hz@1MHz is obtained at the highest tuning frequency..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 27 (2019)
A low-complexity method for concealed object detection in active millimeter-wave images
WANG Chong-Jian, SUN Xiao-Wei, and YANG Ke-Hu
Active millimeter wave imaging (AMWI) is an efficient way to detect dangerous objects concealed under clothes. However, because the images acquired by AMWI are often obscure and some of concealed objects are small in size, the automatic detection and localization of the objects remain as a challenging problem. YaoActive millimeter wave imaging (AMWI) is an efficient way to detect dangerous objects concealed under clothes. However, because the images acquired by AMWI are often obscure and some of concealed objects are small in size, the automatic detection and localization of the objects remain as a challenging problem. Yao.
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 32 (2019)
An optical design for dual-band infrared diffractive telescope
WANG Hao, KANG Fu-Zeng, ZHAO Wei, and LI Yi-Chao
In this paper, the double-layer harmonic diffractive element (HDE) structure is investigated and the optimization procedure is based on the equation of diffraction efficiency of the double-layer diffractive optical element. The diffraction efficiency of the system in the designed middle and far infrared wavebands is laIn this paper, the double-layer harmonic diffractive element (HDE) structure is investigated and the optimization procedure is based on the equation of diffraction efficiency of the double-layer diffractive optical element. The diffraction efficiency of the system in the designed middle and far infrared wavebands is larger than 99%, which improves the image contrast and the imagequality significantly. A new dual-band infrared double-layer HDE telescope is designed, which can work in the middle and far infrared wavebands. It is shown that the system approximately attains diffraction limit and is easy to processed..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 39 (2019)
Preparation of nanocrystalline GZO/CdS bilayer films using magnetron sputtering and GZO/CdS/p-Si heterojunction photovoltaic device
HE Bo, XU Jing, NING Huan-Po, XING Huai-Zhong, WANG Chun-Rui, ZHANG Xiao-Dong, MO Guan-Kong, and SHEN Xiao-Ming
In this work, Ga doped ZnO (GZO)/CdS bilayer films were prepared on p-Si substrate by magnetron sputtering to form GZO/CdS/p-Si heterojunction device. The structural, optical and electrical properies of the nanocrystalline GZO/CdS bilayer films were studied by XRD, SEM, XPS, UV-VIS spectrophotometer and Hall effect meaIn this work, Ga doped ZnO (GZO)/CdS bilayer films were prepared on p-Si substrate by magnetron sputtering to form GZO/CdS/p-Si heterojunction device. The structural, optical and electrical properies of the nanocrystalline GZO/CdS bilayer films were studied by XRD, SEM, XPS, UV-VIS spectrophotometer and Hall effect measurement. The J-V curve of GZO/CdS/p-Si heterojunction device shows good rectifying behavior. And the value of IF/IR (IF and IR stand for forward and reverse current, respectively) at ±3 V is found to be as high as 21. The results indicate that the nanocrystalline GZO/CdS/p-Si heterojunction possesses good diode characteristic. High photocurrent density is obtained under a reverse bias. The nanocrystalline GZO/CdS/p-Si heterojunction device exhibits clear photovoltaic effect. Because the lattice constant of CdS is between GZO and Si, it can be used for a buffer layer between GZO and Si, to effectively reduce the interface states between GZO and p-Si. Therefore, we observed the clear photovoltaic effect of GZO/CdS/p-Si heterojunction..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 44 (2019)
Flexible matesurface-based Terahertz super-absorber
PAN Xiao-Hang, XU Hao, YU Wei-Wei, SHEN Hong, HAO Jia-Ming, SUN Yan, SHEN Yue, MENG Xiang-Jian, and DAI Ning
In recent years, Metamaterials, artificial electromagnetic materials that are constructed by sub-wavelength units, have demonstrated unusual abilities to manipulate electromagnetic waves and promised many potential applications. One of the most intriguing applications of metamaterials is to function as high performanceIn recent years, Metamaterials, artificial electromagnetic materials that are constructed by sub-wavelength units, have demonstrated unusual abilities to manipulate electromagnetic waves and promised many potential applications. One of the most intriguing applications of metamaterials is to function as high performance absorbing medium. In this work, a new type of plasmonic flexible metasurface-based super-absorber for Terahertz waves is designed, fabricated and characterized. Dependences of absorption on the optical properties of component materials and geometric parameters are optimized by full-wave numerical simulations, and then confirmed by experiments. Experimental results show that an absorption peak value of 99% is obtained at the frequency of 3 THz, which are in good agreement with numerical simulations..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 50 (2019)
Realization of a continuous-zoom infrared optical system with high ratio and large relative aperture
YU Yang, ZHOU Pan-Wei, PAN Zhao-Xin, and JIAN Yi
A new continuous zoom structure was described, and a new independent zoom group was added on the classical four-group-mechanical-compensation. And larger zoom ratio was achieved by the way of two zoom groups cascading. This mathematical model was deduced. Then, according to the cooled mid-wave infrared detector, a contA new continuous zoom structure was described, and a new independent zoom group was added on the classical four-group-mechanical-compensation. And larger zoom ratio was achieved by the way of two zoom groups cascading. This mathematical model was deduced. Then, according to the cooled mid-wave infrared detector, a continuous-zoom infrared optical system with large zoom ratio and large relative aperture was designed. And the problem that it’s hard for a zoom optical system to achieve both large zoom ratio and large relative aperture was solved. This optical system can zoom from 6 mm to 330 mm, which means it can reach 55x zoom ratio while the F number is 2 constantly. The working waveband was 3.7~4.8 μm, the cold shield efficiency was 100%.It contains only eight lenses, three of them move in order to change the focal length. The result shows that the zoom curves are quite smooth and the image quality is quite good in the whole zoom range. The laboratory test and the out-door imaging experiment shows that the image quality is quite good in the whole zoom range. It proves the application effect of this new kind of zoom model, and shows that the system reaches its design goal..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 55 (2019)
Noise analysis of a CMOS TDI sensor with on chip signal accumulation in analog domain
JI Cheng, and Chen Yong-Ping
This article proposes a 16-stage on-chip analog accumulation circuit architecture to realize time delay integration(TDI). The accumulation unit is based on charge amplifiers. The temporal noise on the analog signal path of the circuit structure is analyzed to enhance the noise performance, and furthermore the model of This article proposes a 16-stage on-chip analog accumulation circuit architecture to realize time delay integration(TDI). The accumulation unit is based on charge amplifiers. The temporal noise on the analog signal path of the circuit structure is analyzed to enhance the noise performance, and furthermore the model of thermal noise suitable for the TDI process is given. The analysis revealed that the total thermal noise is composed of charge transfer noise and direct sampled noise, according to different stages of accumulators. The relations of each noise component versus circuit gain and corresponding method to suppress it are given. Finally, a 16×256 test chip is taped out under the 0.5 μm CIS process, and test results indicate the improvement of 11.22 dB in SNR at the 16 TDI stages..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 61 (2019)
Low-loss terahertz waveguide and its imaging application
LI Shuai, DAI Zi-Jie, GAO Xiang, ZHAN Tao, ZHAO De-Long, GONG Cheng, and LIU Wei-Wei
High-performance terahertz functional devices have great significance in the generation, transmission and detection of terahertz waves. This paper reports a Kagome-type low-loss terahertz waveguide and its imaging applications. Firstly, anti-resonant waveguide theory was used to design a Kagome terahertz waveguide withHigh-performance terahertz functional devices have great significance in the generation, transmission and detection of terahertz waves. This paper reports a Kagome-type low-loss terahertz waveguide and its imaging applications. Firstly, anti-resonant waveguide theory was used to design a Kagome terahertz waveguide with low loss transmission at 0.1 THz, which has a theoretical loss as low as 0.012 cm-1. Secondly, the waveguide was fabricated by 3D printing technology. The experimental loss is 0.0153 cm-1, and the beam divergence angle at the end of the waveguide is about 6±0.5 degree. Finally, a reconfigurable terahertz imaging system was set up based on the waveguide, which realizes reflection and transmission imaging for a hidden blade and ore respectively. This technology has great application prospects in the underground long-distance exploration..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 68 (2019)
Design of dual-polarized monopulse antenna at W-band
MENG Hong-Fu, CHEN Yang, and DOU Wen-Bin
In order to detect the polarization properties of the target, a dual-polarized monopulse Cassegrain antenna at W-band is proposed. The antenna is composed of the main-reflector, the sub-reflector, the feed horns, the orthomode transducer, and the sum-differential network. The aperture diameter of the antenna is 137 mm,In order to detect the polarization properties of the target, a dual-polarized monopulse Cassegrain antenna at W-band is proposed. The antenna is composed of the main-reflector, the sub-reflector, the feed horns, the orthomode transducer, and the sum-differential network. The aperture diameter of the antenna is 137 mm, the feed contains five horns, the orthomode transducer is designed using the tapered waveguide, and the sum-differential network is realized by the planer coupler. The feed horns, orthomode transducer, and sum-differential network are integrated designed to reduce the insertion loss and compress the size of the antenna. The measured results show that the impedance bandwidth of the antenna is about 3.7 GHz, the polarization isolation is greater than 35 dB, the maximal gain of the sum beam is about 37.9 dBi, the sidelobe level is below -15 dB, and the null depth of the differential beam is better than -25 dB. The antenna shows good dual-polarized monopulse performance at W-band..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 74 (2019)
Graphene oxide: progress in preparation, reduction and application
ZHANG Qian, TANG Li-Bin, LI Ru-Jie, XIANG Jin-Zhong, HUANG Qiang, and LAU Shu-Ping
With the rapid development of graphene industry, graphene oxide has attracted much attention as an important intermediate product of the preparation of graphene. Due to its excellent physical and chemical properties, it has been widely used in multitudinous fields. Various structural models, preparation methods, properWith the rapid development of graphene industry, graphene oxide has attracted much attention as an important intermediate product of the preparation of graphene. Due to its excellent physical and chemical properties, it has been widely used in multitudinous fields. Various structural models, preparation methods, properties and related applications, as well as the reduction of graphene oxide are summarized. The choice of oxidants and reduction agents were found to be important in the reaction. The basic selective principles are discussed after comparing various methods. Finally, it is pointed out that there are still some problems to be solved in the preparation and reduction of graphene oxide. The prospect of graphene oxide on its development and influence will also be evaluated..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 79 (2019)
Design method of Bernal-Stacked bilayer graphene 1.06 μm resonance-enhanced photodetector
NIU Hai-Sha, ZHU Lian-Qing, and LIU Kai-Ming
Graphene has a low absorption rate of light. By combining with an optical resonant cavity to restrict the light field, the absorption rate of the graphene detector element can be effectively improved. Based on the theory of electromagnetic field transmission, the optical field distribution in the bilayer graphene opticGraphene has a low absorption rate of light. By combining with an optical resonant cavity to restrict the light field, the absorption rate of the graphene detector element can be effectively improved. Based on the theory of electromagnetic field transmission, the optical field distribution in the bilayer graphene optical resonator is deduced, a mathematical model for the transmission matrix of the resonant enhanced photodetector is established, and a resonant enhanced photodetector for the Bernal-Stacked bilayer graphene is established. The structural parameters are numerically calculated and the detector performance is analyzed. The results show that, the optical absorption rate of bilayer graphene reaches up to 96.78% for a 1.06 μm wavelength resonant enhanced photodetector, which greatly improves the detection ability of weak optical signals..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 91 (2019)
Design of a photo-excited broadband tunable terahertz absorber
CHENG Yong-Zhi, ZUO Xuan, HUANG Mu-Lin, WANG Tong-Nian, and GONG Rong-Zhou
A photo-excited and polarization insensitive broadband tunable terahertz metamaterial absorber (MMA) based on the photo-sensitive material of silicon (Si) is proposed. The unit-cell structure of this MMA is consisting of compact split-ring resonator structure filled with silicon, mediate medium layer and metal ground-pA photo-excited and polarization insensitive broadband tunable terahertz metamaterial absorber (MMA) based on the photo-sensitive material of silicon (Si) is proposed. The unit-cell structure of this MMA is consisting of compact split-ring resonator structure filled with silicon, mediate medium layer and metal ground-plane. The working frequency and absorption intensity of this terahertz MMA could be effectively tuned, when the conductivity of silicon was changed by the varied incident optical intensity. The simulation results demonstrate that this MMA is dynamically adjusted in the frequency range from 0.852 THz to 0.442 THz when the conductivity of silicon increases from 1.0×103 S/m to the 5.0×105 S/m. In addition, its relative bandwidth is as much as 63.37% and absorption modulation depth is up to 60.22%. The further simulation indicates that the MMA has characteristics of polarization insensitive and wide incident angle..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 97 (2019)
Self-adaptive cloud detection approach for GaoFen-1 optical remote sensing data
MENG Shi-Li, PANG Yong, ZHANG Zhong-Jun, and LI Zeng-Yuan
Cloud detection for remote sensing imageries is a fundamental as well as significant step due to the inevitable existence of large amount of clouds in the optical remote sensing data. A highly efficient cloud detection approach is capable of saving data collection cost and improving data utilization efficiency. HomomorCloud detection for remote sensing imageries is a fundamental as well as significant step due to the inevitable existence of large amount of clouds in the optical remote sensing data. A highly efficient cloud detection approach is capable of saving data collection cost and improving data utilization efficiency. Homomorphic filtering algorithm is one of the most commonly methods that based on single-scene image for detecting clouds. This algorithm has the advantage of fast computation and high accuracy in cloud areas detection. However, the detected cloud areas are heavily dependent on the cut-off frequency of the homomorphic filter. The homomorphic filtering progress usually uses cut-off frequency with empirical value which might not be applicable to large amount of intricate input data. Therefore, this paper aims to construct the relationship between the image spectra power and the filter cut-off frequency. Based on the domestic high spatial resolution optical remote sensing data GF-1, this research makes the detection of clouds could be process to achieve a bulk deal. Our approach make the cut-off frequency self-adaptive changes rather than used empirical value when compared with the traditional homomorphic filtering, thus it could be able to meet more complicated scenarios. Further, the post-processing steps including whiteness index, spectral threshold, and morphological opening and closing operators are applied to coarse cloud mask to optimize results. We have tested on 98 GF-1 high resolution multispectral imageries, results indicated that our approach is capable of detecting cloud as well as haze areas with high accuracy of 93.81%. This novel self-adaptive method shows its great application potential for real-time and high efficient cloud detection, meanwhile reduced the error detection rates caused by high reflectance ground objects..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 103 (2019)
A nonlinear unmixing algorithm dealing with spectral variability for hyperspectral imagery
ZHI Tong-Xiang, YANG Bin, and WANG Bin
Nonlinear unmixing can explain the nonlinear mixing effect in complex scenarios of hyperspectral imagery, but the spectral variability of ground objects is one of the difficulties. An unsupervised nonlinear unmixing algorithm dealing with spectral variability is proposed in this paper. The original hyperspectral image Nonlinear unmixing can explain the nonlinear mixing effect in complex scenarios of hyperspectral imagery, but the spectral variability of ground objects is one of the difficulties. An unsupervised nonlinear unmixing algorithm dealing with spectral variability is proposed in this paper. The original hyperspectral image data is implicitly mapped into a high-dimensional feature space through a kernel function and then linear unmixing is applied for hyperspectral imagery in combination with spectral variability in this space. Further, local smoothness constraint is added on abundances and coefficients of spectral variability according to the distribution characteristics of ground objects. Experimental results on simulated and real hyperspectral data indicate that the proposed algorithm can overcome the spectral variability problem in different nonlinear mixing scenarios and improve the unmixing accuracy..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 115 (2019)
Infrared thermal image ROI extraction algorithm based on fusion of multi-modal feature maps
ZHU Li, ZHANG Jing, FU Ying-Kai, SHEN Hui, ZHANG Shou-Feng, and HONG Xiang-Gong
Infrared thermal image region of interest (ROI) extraction has important significance for fault detection, target tracking and so on. In order to solve the problems of many infrared thermal image disturbances, artificial markers and low accuracy, a ROI of infrared thermal image extraction algorithm based on fusion of mInfrared thermal image region of interest (ROI) extraction has important significance for fault detection, target tracking and so on. In order to solve the problems of many infrared thermal image disturbances, artificial markers and low accuracy, a ROI of infrared thermal image extraction algorithm based on fusion of multi-modal feature map is proposed. Multi-modal feature maps are constructed by contrast, entropy, and gradient features, and region filling is performed to achieve ROI extraction. New algorithm is applied to actual collected photovoltaic solar panel image. Simulation results show that the proposed algorithm has high average precision (93.0553%), high average recall (902841%), F1 index and J index are better than Grab Cut, less artificial marks, etc.. It can be effectively used for ROI extraction of infrared thermal images..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 38, Issue 1, 125 (2019)
