Journals >Journal of Infrared and Millimeter Waves
Contents
2004
Volume: 23 Issue 5
21 Article(s)
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Research Article
EFFICIENT SCHEME FORDETERMINING FRACTAL SCALELESS RANGE
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The terrain model basedon fractal character can sufficiently represent the statistical texture features of theterrain. Better model and higher resolution DEM (Digital Elevation Model) data can beobtained from the lower resolution data by using fractal interpolation. The determinationof fractal scaleless range is very iThe terrain model basedon fractal character can sufficiently represent the statistical texture features of theterrain. Better model and higher resolution DEM (Digital Elevation Model) data can beobtained from the lower resolution data by using fractal interpolation. The determinationof fractal scaleless range is very important for computing the fractal characteristicparameters and modeling the digital elevation. The traditional method for determining thefractal scaleless range usually adopts the mutual test between people and compute.However, this method tends to be too subjective. Hence, we offer an auto-determiningmethod, which has been proved to be concise, effective and efficient by experimental results..
Journal of Infrared and Millimeter Waves
- Publication Date: Jan. 01, 1900
- Vol. 23, Issue 5, 321 (2004)
STRAIN AND RELAXATION OF MBE-HgCdTe FILMS
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The tilt relation and lattice misfit phenomenon between MBE-HgCdTe layers and different substrates were studied by employing reciprocal lattice mappings technology. The precise fit zinc composition in Cd 1-yZn yTe substrates was determined by analyzing the elastic deformation in MBE-HgCdTe layers. The result shows thatThe tilt relation and lattice misfit phenomenon between MBE-HgCdTe layers and different substrates were studied by employing reciprocal lattice mappings technology. The precise fit zinc composition in Cd 1-yZn yTe substrates was determined by analyzing the elastic deformation in MBE-HgCdTe layers. The result shows that MBE-HgCdTe epitaxial layers and substrates are tilted with respect to each other, and the tilt angle increases with the lattice mismatch. In the case of little mismatch between substrate and layer, the layer is strained with partially relaxation of stress. While the layer is full relaxed, the lattice mismatch becomes large. In this case, the HgCdTe layers have more misfit dislocations and larger width of half maximum..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 325 (2004)
MAGNETO-TRANSPORT OF ELECTRON SYMMETRIC AND ANTISYMMRTRIC STATES IN HIGHLY DOPED InGaAs/InAlAs SINGLE QUANTUM WELL
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Beating patterns in longitudinal resistance caused by the symmetric and antisymmetric states were observed in a heavily doped InGaAs/InAlAs quantum well by using variable temperature Hall measurement. The energy gap of symmetric and antisymmetric states is estimated to be 4meV from the analysis of beating node positionBeating patterns in longitudinal resistance caused by the symmetric and antisymmetric states were observed in a heavily doped InGaAs/InAlAs quantum well by using variable temperature Hall measurement. The energy gap of symmetric and antisymmetric states is estimated to be 4meV from the analysis of beating node positions. In addition, the temperature dependences of the subband electron mobility and concentration were also studied from the mobility spectrum and multicarrier fitting procedure..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 329 (2004)
EFFECTS OF PROBE-BEAM POLARIZATION DIRECTION ON THz DETECTION IN ZnTe
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The effects of probe-beam polarization direction on the THz detection in ZnTe were investigated experimentally. By keeping the THz radiation intensity unchanged, we observed two minimums with an interval of 1800 when the direction of the probe-beam polarization θ was changed from 0 to 360°. Non-zero THz radiation The effects of probe-beam polarization direction on the THz detection in ZnTe were investigated experimentally. By keeping the THz radiation intensity unchanged, we observed two minimums with an interval of 1800 when the direction of the probe-beam polarization θ was changed from 0 to 360°. Non-zero THz radiation was detected in the middle of the two minimums ( θ =90°). The Jones Matrix method was employed to simulate the experiments by assuming the electro-optic effect in ZnTe under a THz field as an equivalent arbitrary wave plate. It was found that all the simulation results were in agreement with the experiments, except for θ =90°. A qualitative explanation based on the interaction between THz photons and TO phonons was presented..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 333 (2004)
ANALYSIS ON THE DECREASE OF SIGNAL MODULATION IN FOURIR TRANSFORM SPECTROMETER
[in Chinese], and [in Chinese]
The causes of decreasing the modulation of the signal of Fourier transform spectrometer were analyzed from theoretical point of view. Specifically the decrease caused by the plane mirror, polarization effects, detector’s lateral shift from the optical axis of the system, plane mirror’s tilt and the vertex shift of one The causes of decreasing the modulation of the signal of Fourier transform spectrometer were analyzed from theoretical point of view. Specifically the decrease caused by the plane mirror, polarization effects, detector’s lateral shift from the optical axis of the system, plane mirror’s tilt and the vertex shift of one corner cube reflector relative to the other was analyzed, and some formulas were deduced and their usages were simply commented..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 337 (2004)
RIGIOURS EXCITATION ANALYSIS FOR NRD WAVE GUIDE WITH TRANSVERSE SLOT
[in Chinese], and [in Chinese]
The excitation of NRD guide is a key-problem to the planar/non-planar microwave hybrid integrated circuit. An efficient excitation method of the LSE 01mode in NRD guide through transverse slot was rigorously analyzed by combining the vector Green’s functions with the moment method. This exciting structure has many advaThe excitation of NRD guide is a key-problem to the planar/non-planar microwave hybrid integrated circuit. An efficient excitation method of the LSE 01mode in NRD guide through transverse slot was rigorously analyzed by combining the vector Green’s functions with the moment method. This exciting structure has many advantages of simple structure, small size, high excitation efficiency and weak energy leakage. And it is of important practical significance in the design of hybrid integrated circuits..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 341 (2004)
HYPERSPECTRAL IMAGE CLASSIFICATION BASED ON MULTIPLE FEATURES DURING MULTIRESOLUTION FUSION
[in Chinese], and [in Chinese]
Because of the high data dimensionality of hyperspectral data, conventional methods are difficult to obtain satisfied results in the study of hyperspectral classification for materials on the ground. In the process of feature images extraction based on wavelet multiresolution fusion, a new method, which uses a feature Because of the high data dimensionality of hyperspectral data, conventional methods are difficult to obtain satisfied results in the study of hyperspectral classification for materials on the ground. In the process of feature images extraction based on wavelet multiresolution fusion, a new method, which uses a feature vector consisting of multiple spacious salient features to determine fusion weights, wass presented. The algorithm can effectively reduce the hyperspectral data dimensionality and obtain the feature images for the successive classification. The experiments on AVIRIS data show that classification accuracy by using the new method is higher than that of using the conventional methods in determining weights..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 345 (2004)
ADAPTIVE COMPREESION OF HYPER-SPECTRAL IMAGES BASED ON UNIFORM TRELLIS-CODED QUANTIZATION
[in Chinese], [in Chinese], and [in Chinese]
An approach for compression of hyper-spectral image based on classification of sub-bands was proposed firstly. The wavelet decomposition was carried out and the sub-bands were partitioned into sub-blocks. Then sub-blocks were classified based on their activity. Based on classification, the algorithm uses prediction to An approach for compression of hyper-spectral image based on classification of sub-bands was proposed firstly. The wavelet decomposition was carried out and the sub-bands were partitioned into sub-blocks. Then sub-blocks were classified based on their activity. Based on classification, the algorithm uses prediction to remove the spectral redundancy, in which the algorithm computes the predictor for each class to reflect local correlation in sub-band images. Then the uniform trellis-coded quantization is used to quantize the error images. At last, entropy encoding of the quantized codeword is performed by adaptive arithmetic encoding. To optimally allocate bits through all series of coefficients, an algorithm for bit allocation based on statistic characteristic of the series of coefficients and R-D characteristic of trellis-coded quantizer was proposed. The experiments show that the approach can efficiently compress hyper-spectral remote sensing images, and the excellent performance of the proposed algorithm is demonstrated..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 349 (2004)
APPLICATION OF INFRARED THERMAL IMAGING IN IDENTIFICATION OF CITRUS ON TREES
[in Chinese], and [in Chinese]
To identify fruits on the tree and determine their locations are the key to harvest fruits by robot. The main methods to locate fruits on trees were compared with. As the low identification rate of common machine vision system, a new method to identify the citrus in a tree canopy by means of infrared thermal imaging waTo identify fruits on the tree and determine their locations are the key to harvest fruits by robot. The main methods to locate fruits on trees were compared with. As the low identification rate of common machine vision system, a new method to identify the citrus in a tree canopy by means of infrared thermal imaging was put forward. About 45 infrared thermal images of citrus on trees were captured from the citrus orchard. It was found that the different thermal distribution among citrus, leaves and branches was about 1℃, and these differences clearly appeared in the gray-level image, which could be easily used to segment the citrus from other parts in the image by using binary image at T=190. Sobel and mask operators were used to extract the edge of the image. The results indicate that it is possible to identify citrus on trees by using infrared thermal imaging, and it is much easier than the methods used before..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 353 (2004)
低阻硅衬底上形成的低损耗共平面波导传输线LOW-LOSS CPW LINE ON LOW-RESISTIVITY SILICON
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Low loss and high performance RF/microwave CPW(coplanar waveguide)were fabricated on thicker porous silicon(PS)/ oxidized porous silicon(OPS) substrate associated with polyimide coating to improve smoothness. PS films with different thickness were formed on both N and P-type Si, and the CPW losses on them were discusseLow loss and high performance RF/microwave CPW(coplanar waveguide)were fabricated on thicker porous silicon(PS)/ oxidized porous silicon(OPS) substrate associated with polyimide coating to improve smoothness. PS films with different thickness were formed on both N and P-type Si, and the CPW losses on them were discussed. The CPW loss on thick PS is intimately close to quartz, and much lower than the combined substrate of poly-Si / oxidized poly-Si growing on a 2000Ω·cm Si wafer. The insertion loss on PS was lower than 5dB/1.2cm in the range of 0-33GHz, and less than 7.5dB/1.2cm in 33-40GHz..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 357 (2004)
NEAR-INFRARED FEMTOSECOND LASER INDUCED COLOR CENTERS IN HIGH-PURITY FUSED SILICA
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Si E′ centers were induced in high-purity silica glass after infrared fs(femtosecond) laser exposure. The concentration of the color centers increased linearly with the laser intensity and the number of scan time below the optical breakdown threshold. From the results of absorption, ESR and photo-luminescence spectra mSi E′ centers were induced in high-purity silica glass after infrared fs(femtosecond) laser exposure. The concentration of the color centers increased linearly with the laser intensity and the number of scan time below the optical breakdown threshold. From the results of absorption, ESR and photo-luminescence spectra measurements before and after fs laser irradiation, the processes of Si E′ center formation were proposed. The self-trapped excitons are ascribed to the main reason of color centers formation..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 360 (2004)
ALTERNATING DIRECTION IMPLICIT FINITE-DIFFERENCE TIME-DOMAIN METHOD FOR PLASMAS
[in Chinese], [in Chinese], and [in Chinese]
The alternating direction implicit finite-difference time-domain (ADI-FDTD) formulation was extended to dispersive media-collisionless unmagnetized plasma for the first time. Electromagnetic interactions of collisionless unmagnetized plasma and electromagnetic wave were calculated by using the method. The update equatiThe alternating direction implicit finite-difference time-domain (ADI-FDTD) formulation was extended to dispersive media-collisionless unmagnetized plasma for the first time. Electromagnetic interactions of collisionless unmagnetized plasma and electromagnetic wave were calculated by using the method. The update equations for collisionless plasma were proposed by using the principle of ADI technique. The unconditional stability of the ADI-FDTD formulation for plasma was analytically derived. The results of numerical experiment confirm that the plasma ADI-FDTD method is consistent with the conventional FDTD method, and its efficiency is higher..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 363 (2004)
THEORETICAL RESEARCH OF QUASI-PHASE-MATCHED ALL-OPTICAL WAVELENGTH CONVERSION IN LiNbO3 WAVEGUIDES
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Periodically poled LiNbO 3(PPLN) waveguide quasi-phase-matched all-optical wavelength conversion was studied theoretically. The analysis suggests useful criteria for the optimization of the fabrication parameters in order to enhance the efficiency of quasi-phase-matched wavelength conversion processes.Periodically poled LiNbO 3(PPLN) waveguide quasi-phase-matched all-optical wavelength conversion was studied theoretically. The analysis suggests useful criteria for the optimization of the fabrication parameters in order to enhance the efficiency of quasi-phase-matched wavelength conversion processes..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 367 (2004)
ANALYSIS OF THE CHARACTERISTICS OF ELECTROMAGNETIC WAVE PROPAGATION IN DIELECTRIC FIBER BUNCHED WAVEGUIDE
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Dielectric fiber bunched waveguide is a kind of cylindric dielectric waveguide array(CDWA). Based on the established theory for two-dimensionally periodic medium, electromagnetic wave propagation in cylindric dielectric waveguide array which was arrayed by a rectanglar array was calculated and analysized. The characterDielectric fiber bunched waveguide is a kind of cylindric dielectric waveguide array(CDWA). Based on the established theory for two-dimensionally periodic medium, electromagnetic wave propagation in cylindric dielectric waveguide array which was arrayed by a rectanglar array was calculated and analysized. The characteristics of wave propagation in cylindric dielectric waveguide array were presented. Besides, these characteristics were compared with those of wave propagation in rectangle dielectric waveguide array. And the results are satisfying..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 371 (2004)
ROBUST ESTIMATION FOR THE DIRECTION OF ARRIVAL BY FRESNEL ZONE PLATE ANTENNA
[in Chinese], [in Chinese], and [in Chinese]
A novel multi-beam adaptive antenna was investigated by considering the spatially distributed source model for local scattering radio propagation in cellular mobile communications. This antenna is consisted of a focusing configuration with Fresnel zone phase-correcting plate (FZP) and feeding array. The robust estimatiA novel multi-beam adaptive antenna was investigated by considering the spatially distributed source model for local scattering radio propagation in cellular mobile communications. This antenna is consisted of a focusing configuration with Fresnel zone phase-correcting plate (FZP) and feeding array. The robust estimation of parameters (direction-of-arrival (DOA) and angular spread) was studied based on the generalized MUSIC algorithm and the maximum likelihood estimation in the case of coherently and incoherently spatially distributed source respectively. Simulation results show that the FZP configuration outperforms the uniformly linear array (ULA) in reducing the estimation errors of the RMS in the considered propagation environment. Therefore a robust estimation of DOA can be achieved with this novel adaptive antenna..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 374 (2004)
SMOOTH INTERPOLATE SOLUTION OF ARMOURED TARGETS' MILLIMETER WAVE RADIOMETRIC BRIGHTNESS TEMPERATURES
[in Chinese], [in Chinese], and [in Chinese]
The passive detection techniques of the millimeter wave radiometer play an important role in homing guidance of anti-armour missile and end-sensing-cartridge. In order to obtain the radiometric brightness temperatures of the armoured target, a Fredholm integral equation of the first kind must be solved. This equation iThe passive detection techniques of the millimeter wave radiometer play an important role in homing guidance of anti-armour missile and end-sensing-cartridge. In order to obtain the radiometric brightness temperatures of the armoured target, a Fredholm integral equation of the first kind must be solved. This equation is ill-posed and its solutions are extremely unstable. The character of the spline interpolation and the condition of the minimum norm of first order differentiator are used, then the smooth interpolation solutions of armored target’s brightness temperatures are obtained, and are used in millimeter wave passive detection..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 377 (2004)
STUDY ON INTRODUCING LASER RADIATED DNA INTO TOMATO
[in Chinese], [in Chinese], and [in Chinese]
Some nonlinear phenomena of nonlinear resonance, chaos, stochastic resonance and stochastic chaos occur in the laser-DNA interactive system, which make DNA mutated and broken up. The laser-radiated exogenous DNA was introduced into the tomato. It is beneficial to the expression of some characters of dominant genes of tSome nonlinear phenomena of nonlinear resonance, chaos, stochastic resonance and stochastic chaos occur in the laser-DNA interactive system, which make DNA mutated and broken up. The laser-radiated exogenous DNA was introduced into the tomato. It is beneficial to the expression of some characters of dominant genes of the donor and the improvement of the descendents qualities of receptors. The peroxidase isoenzyme of the donor, the receptor, and their descendents were analyzed. Our result shows that the pero.................
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 380 (2004)
NEAR INFRARED MICRO PULSE LIDAR OF PROFILING ATOMOSPHERIC CO2
[in Chinese], [in Chinese], and [in Chinese]
um-wave length, fiber-based micro pulse lidar of profiling atmospheric CO 2 was designed, The performance of this lidar was simulated. The transmitter of micro pulse lidar is based on semiconductor laser plus erbium-doped fiber amplifier with a saturated output power of 37dBm. The receiver employs photon counter and neum-wave length, fiber-based micro pulse lidar of profiling atmospheric CO 2 was designed, The performance of this lidar was simulated. The transmitter of micro pulse lidar is based on semiconductor laser plus erbium-doped fiber amplifier with a saturated output power of 37dBm. The receiver employs photon counter and near infrared photomultiplier tube with quantum efficiency of 1%. A polarization-independent fiber-optic circulator is used as the transmit-receive switch. The system utilizes fiber devices for almost all components, e.g. wavelength-division-multiplexers/demultiplexers, isolator,filter,coupler, which make the system robust. Characteristic of this lidar is micro pulse energy 20uJ, high repetition rate of 20kHz and miniaturization. Signal simulations indicate that signal-to-noise ratio below 4.7km is more than 10∶1(18×106 pulse).Anode dark count of 2×105 /s limits the system performance. New InGaAs/Si APD with separate absorption and multiplication region will improve the lidar performance..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 384 (2004)
STUDY ON PRACTICAL MAGNETO-STATIC SURFACE WAVE BAND-PASS FILTER
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The designing model of magneto-static surface wave (MSSW) band-pass filter was established according to the MSSW fundamental theory. Based on the model and putting emphasis on center frequency and bandwidth control, the filter was devised, made and tested with the view of practical MSSW filter. The performance of the fThe designing model of magneto-static surface wave (MSSW) band-pass filter was established according to the MSSW fundamental theory. Based on the model and putting emphasis on center frequency and bandwidth control, the filter was devised, made and tested with the view of practical MSSW filter. The performance of the filter manufactured is in accordance with the theoretical designing with center frequency from 4.2GHz～5.2GHz, bandwidth 180MHz 6MHz at level-3dB, insertion loss 11dB and suppression of side bands more than 30dB, Thus, the practical MSSW filter prototype has been obtained. By raising the center frequency further, the technique will have broad prospect in the millimeter bands..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 389 (2004)
DESIGN AND DEPOSITION OF INFRARED/VISIBLE WIDE-BAND COLOR SEPARATION FILTERS
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Infrared/visible color separation filters take an important role in imaging spectrum technique. We applied the concept of induced transmission to design the filter, and combined optical distinguish method and quartz crystal monitor XTC-2 technique to control the thickness of each coating accurately. Finally the satisfiInfrared/visible color separation filters take an important role in imaging spectrum technique. We applied the concept of induced transmission to design the filter, and combined optical distinguish method and quartz crystal monitor XTC-2 technique to control the thickness of each coating accurately. Finally the satisfied wide bandwidth filter was obtained. Its spectrum result is in the front of the same kind of filters reported before..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 393 (2004)
SEVERAL FACTORS OF INFLUENCING MEASUREMENT ACCURACY FOR A PRACTICAL REAL-TIME TEMPERATURE MEASUREMENT SYSTEM
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Based on the Kirchhoff law, a practical temperature real-time measurement system using laser diode and LiTaO 3 pyroelectric detector was developed. According to the infrared radiation characteristics of the measurement surface, surroundings, transmission features of atmosphere and the temperature measurement system itsBased on the Kirchhoff law, a practical temperature real-time measurement system using laser diode and LiTaO 3 pyroelectric detector was developed. According to the infrared radiation characteristics of the measurement surface, surroundings, transmission features of atmosphere and the temperature measurement system itself, detailed analyses were given on the factors of influencing temperature measurement accuracy. And the measures on improving the temperature measurement accuracy were put forward. Experimental results show that the temperature measurement inaccuracy is within 0.3%, and it is suitable for the requirements..
Journal of Infrared and Millimeter Waves
- Publication Date: Oct. 01, 2004
- Vol. 23, Issue 5, 396 (2004)
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