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1991 Vol. 13, No. 6
Display Method:
1991, 13(6): 561-567.
Abstract:
Equivalent two-port measurement equations for reciprocal n-port network is derived generally. As an example, applications of these equations, measurement details and data-processing methods are discussed for any three-port network. A set of measurement system which is made from the automatic slotted line and the program controlled short-circuit is presented in order to realize rapid and automatic measurements of S-parameters of any reciprocal multi-port network. Experimental data are given of a H-plane T three-port network.
Equivalent two-port measurement equations for reciprocal n-port network is derived generally. As an example, applications of these equations, measurement details and data-processing methods are discussed for any three-port network. A set of measurement system which is made from the automatic slotted line and the program controlled short-circuit is presented in order to realize rapid and automatic measurements of S-parameters of any reciprocal multi-port network. Experimental data are given of a H-plane T three-port network.
1991, 13(6): 568-574.
Abstract:
The subsequence interpolation algorithm using FFT has been generalized for interpolation of 2-D signal. The subsequence interpolation algorithm using FHT for 2-D signal is proposed. The algorithm will be useful when one needs to store or transmit an image sampled at lower rate and reconstruct it later with better quality. This new algorithm is more suitable for parallel processing.
The subsequence interpolation algorithm using FFT has been generalized for interpolation of 2-D signal. The subsequence interpolation algorithm using FHT for 2-D signal is proposed. The algorithm will be useful when one needs to store or transmit an image sampled at lower rate and reconstruct it later with better quality. This new algorithm is more suitable for parallel processing.
1991, 13(6): 575-582.
Abstract:
By using center projection image sequence to estimate 3-D motion parameters, one needs to know the corresponding relationship between the feature of motion object in space and the projection coordinate in image plane. In order to avoid using the relationship of feature correspondence, the tensor analysis method in the affine transformation system is presented, and the simulation data of experimental results are given.
By using center projection image sequence to estimate 3-D motion parameters, one needs to know the corresponding relationship between the feature of motion object in space and the projection coordinate in image plane. In order to avoid using the relationship of feature correspondence, the tensor analysis method in the affine transformation system is presented, and the simulation data of experimental results are given.
1991, 13(6): 583-589.
Abstract:
An approximation algorithm is presented for augmenting an undirected weighted graph to a K-edge-connected graph. The algorithm is useful for designing a realizable network.
An approximation algorithm is presented for augmenting an undirected weighted graph to a K-edge-connected graph. The algorithm is useful for designing a realizable network.
1991, 13(6): 590-596.
Abstract:
A method for analyzing electrical excitation mode of electromagnetic measurement while drilling (EM-MWD) is proposed. By this method, a lot of calculations for EM-MWD has been done, and some very important data have been obtained, in which the electric field intensity distribution patterns on the earth s surface, the dependent relations of electric field intensity upon the frequency and the input impedance of the transmission equipment are included. All of the calculated results agree well with that of the laboratory test and the shallow well test.
A method for analyzing electrical excitation mode of electromagnetic measurement while drilling (EM-MWD) is proposed. By this method, a lot of calculations for EM-MWD has been done, and some very important data have been obtained, in which the electric field intensity distribution patterns on the earth s surface, the dependent relations of electric field intensity upon the frequency and the input impedance of the transmission equipment are included. All of the calculated results agree well with that of the laboratory test and the shallow well test.
1991, 13(6): 597-602.
Abstract:
The mathematical expression of the antenna radiation efficiency which is measured using radiometer is derived, then the methods for measuring antenna radiation efficiency and the experimental results are presented.
The mathematical expression of the antenna radiation efficiency which is measured using radiometer is derived, then the methods for measuring antenna radiation efficiency and the experimental results are presented.
1991, 13(6): 603-610.
Abstract:
A free electron laser with electromagnetic pumping wave is studied. A drifting and rotating electron ring with large radius comes from a magnetic cusp, goes through a cylindrical waveguide and interacts with TEn modes of the waveguide. By making use of the Vlasov distribution theory and the three dimensional wave equation of waveguide modes, the dispersion relation of scattered waves in Compton region is deduced. According to the numerical analysis, the growth rate and frequency of scattered wave as a function of guide mag netic field, electron beam energy. electron cvclotron ratio and radial position of electron ring have been discussed.
A free electron laser with electromagnetic pumping wave is studied. A drifting and rotating electron ring with large radius comes from a magnetic cusp, goes through a cylindrical waveguide and interacts with TEn modes of the waveguide. By making use of the Vlasov distribution theory and the three dimensional wave equation of waveguide modes, the dispersion relation of scattered waves in Compton region is deduced. According to the numerical analysis, the growth rate and frequency of scattered wave as a function of guide mag netic field, electron beam energy. electron cvclotron ratio and radial position of electron ring have been discussed.
1991, 13(6): 611-617.
Abstract:
The anodization of Al film on InP substrate and the properties of anodic Al2O3/lnP have been investigated by AES, DLTS, I-V, C-V and ellipsometer. The results show that the anodic oxide Al2O3 has the permitivity of 11-12 and the resistivity of 1.31013 ohm-cm. Interface state density at Al2O3/InP is about 1011cm-2eV-1. DLTS reveals that there is continuously-distributed interface electron traps at Al2O3/lnP interface. Anodic oxide Al2O3 exhibits good stability and electrical properties and could be used for passivation, diffusion mask and gate insulator etc.
The anodization of Al film on InP substrate and the properties of anodic Al2O3/lnP have been investigated by AES, DLTS, I-V, C-V and ellipsometer. The results show that the anodic oxide Al2O3 has the permitivity of 11-12 and the resistivity of 1.31013 ohm-cm. Interface state density at Al2O3/InP is about 1011cm-2eV-1. DLTS reveals that there is continuously-distributed interface electron traps at Al2O3/lnP interface. Anodic oxide Al2O3 exhibits good stability and electrical properties and could be used for passivation, diffusion mask and gate insulator etc.
TWO-DIMENSIONAL NUMERICAL SIMULATION FOR VDMOS DEVICE AND THE OPTIMIZATION OF ITS TYPICAL PARAMETERS
1991, 13(6): 618-624.
Abstract:
A software for numerical simulation of power MOSFET, called TDSPM, is developed. In the program, DDM model is used. The velocity-electrical field characteristics and generation/recombination effect in high electrical field region for electrons are specially considered for simulating device performances at high voltage including the case of breakdown. The entirely coupled method is used. To enlarge the increment of applied voltage, the truncation method is employed. With the truncation method, the increment of drain-to-source of 100--200V can be used in saturation region. TDSPM is applied to simulation of VDMOS. The output characteristics are simulated. Internal distributions of some physical parameters are calculated and investigated. Special emphasis is placed on breakdown. At last the software is applied to optimization of VDMOS.
A software for numerical simulation of power MOSFET, called TDSPM, is developed. In the program, DDM model is used. The velocity-electrical field characteristics and generation/recombination effect in high electrical field region for electrons are specially considered for simulating device performances at high voltage including the case of breakdown. The entirely coupled method is used. To enlarge the increment of applied voltage, the truncation method is employed. With the truncation method, the increment of drain-to-source of 100--200V can be used in saturation region. TDSPM is applied to simulation of VDMOS. The output characteristics are simulated. Internal distributions of some physical parameters are calculated and investigated. Special emphasis is placed on breakdown. At last the software is applied to optimization of VDMOS.
1991, 13(6): 632-636.
Abstract:
The inductively coupled plasma-atomic emission spectroscopy (ICPAES) analytic technique is difficult to develop because of its complex spectral interferences. The algorithms for correcting interferences need a large computation, thus the real-time correction is hard to reach on general microcomputer. A spectral interference fast correcting system (SIFCS) is discussed on algorithms and processor performance. The hardware of SIFCS is a TMS32020 signal processing board on IBM-PC I/O channel. The dual-port RAM is deposited in hardware design. The software of SIFCS consists of a correction program based on a new efficient algorithm and a master program on IBM-PC. Experiments show that the interference correction on SIFCS is 50～100 times faster than on IBM-PC7AT, so that the real-time interfer- ence correction is possible.
The inductively coupled plasma-atomic emission spectroscopy (ICPAES) analytic technique is difficult to develop because of its complex spectral interferences. The algorithms for correcting interferences need a large computation, thus the real-time correction is hard to reach on general microcomputer. A spectral interference fast correcting system (SIFCS) is discussed on algorithms and processor performance. The hardware of SIFCS is a TMS32020 signal processing board on IBM-PC I/O channel. The dual-port RAM is deposited in hardware design. The software of SIFCS consists of a correction program based on a new efficient algorithm and a master program on IBM-PC. Experiments show that the interference correction on SIFCS is 50～100 times faster than on IBM-PC7AT, so that the real-time interfer- ence correction is possible.
1991, 13(6): 637-639.
Abstract:
The generalized magnitude-symmetry theorem of lossless reciprocal network is extended to lossless non-reciprocal network. Two illustrations for application of the theorem are given.
The generalized magnitude-symmetry theorem of lossless reciprocal network is extended to lossless non-reciprocal network. Two illustrations for application of the theorem are given.
1991, 13(6): 640-643.
Abstract:
A new method for measuring target s radar cross-section (RCS) in general laboratory by means of six-port technique and a new error correcting model are given. The sir-port reflectometer circuit for testing RCS and some experimental results are also presented.
A new method for measuring target s radar cross-section (RCS) in general laboratory by means of six-port technique and a new error correcting model are given. The sir-port reflectometer circuit for testing RCS and some experimental results are also presented.
1991, 13(6): 644-647.
Abstract:
The characteristics of numerical computation of node unit current model is investigated, and new method for computing integrals of surface patch modeling is presented. Using this method, the pseudosingular point in integral calculation is eliminated, and an efficient technique for computing integral in high frequency condition is provided. The numerical computing technique developed provides theoretical basis for applying the node unit current model to high frequency problems.
The characteristics of numerical computation of node unit current model is investigated, and new method for computing integrals of surface patch modeling is presented. Using this method, the pseudosingular point in integral calculation is eliminated, and an efficient technique for computing integral in high frequency condition is provided. The numerical computing technique developed provides theoretical basis for applying the node unit current model to high frequency problems.
1991, 13(6): 648-652.
Abstract:
The natural frequencies of a model missile have been computed by using the magnetic field integral equation and moment method. The trajectories of them in the complex plane for some parameters are shown.
The natural frequencies of a model missile have been computed by using the magnetic field integral equation and moment method. The trajectories of them in the complex plane for some parameters are shown.
1991, 13(6): 653-658.
Abstract:
The principle of PALn colour television decoder is described: the design of PALN colour television decoder circuits is explained; the testing methods for PALn colur television decoder are introduced.
The principle of PALn colour television decoder is described: the design of PALN colour television decoder circuits is explained; the testing methods for PALn colur television decoder are introduced.
1991, 13(6): 659-662.
Abstract:
An experiment of cleaning the organic molecules absorbed on the interface with photochemical method is described. The mechanism, the experimental method and the AES results are given. The results show that the photosensitized oxidation process of UV/O3 for the organic molecules is effective not only for the surface but also for the interface of substances.
An experiment of cleaning the organic molecules absorbed on the interface with photochemical method is described. The mechanism, the experimental method and the AES results are given. The results show that the photosensitized oxidation process of UV/O3 for the organic molecules is effective not only for the surface but also for the interface of substances.
1991, 13(6): 663-665.
Abstract:
The estimation of the cathode current density of CRTs from cathode image by means of TV camera and micro-processing technique is proposed. It is supposed that the relation between the analog current and the summation of the digital current value of picture element is equal. Then the cathode current density can be obtained from the processed emission current density distribution curve.
The estimation of the cathode current density of CRTs from cathode image by means of TV camera and micro-processing technique is proposed. It is supposed that the relation between the analog current and the summation of the digital current value of picture element is equal. Then the cathode current density can be obtained from the processed emission current density distribution curve.
1991, 13(6): 625-631.
Abstract:
The fully integrated continuous-time filter is one of the most important advances in analog VLSI recently. The state of art of fully integrated continuous-time filter is reviewed and its most important advances are discussed. The frontiers and open problems of fully integrated continuous-time filter researches are reviewed too.
The fully integrated continuous-time filter is one of the most important advances in analog VLSI recently. The state of art of fully integrated continuous-time filter is reviewed and its most important advances are discussed. The frontiers and open problems of fully integrated continuous-time filter researches are reviewed too.
