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1983 Vol. 5, No. 5
Display Method:
1983, 5(5): 265-270.
Abstract:
In the paper, a 3-lens optical processor is deseribed. Its features are quick and easy adjustment, wide adaptability, easy assembly and disassembly. It is a good optical processor for processing the synthetic aperture radar signal in the field.
In the paper, a 3-lens optical processor is deseribed. Its features are quick and easy adjustment, wide adaptability, easy assembly and disassembly. It is a good optical processor for processing the synthetic aperture radar signal in the field.
1983, 5(5): 271-279.
Abstract:
Based on O. R. Mitchell s paper (1977), a further study is made on the problem of removing cloud interference in remote sensing images. Some advances are made: (1) re-established a new mathematical modei for cloud distortion; (2) suggested, with this model, a two-stage filtering scheme; (3) developed a filtering method by noise concelling and an approach of 3-dimension processing of the multispectral data. Simulation experiment with microcomputer and actual experiment with S101 image processing system both show good results.
Based on O. R. Mitchell s paper (1977), a further study is made on the problem of removing cloud interference in remote sensing images. Some advances are made: (1) re-established a new mathematical modei for cloud distortion; (2) suggested, with this model, a two-stage filtering scheme; (3) developed a filtering method by noise concelling and an approach of 3-dimension processing of the multispectral data. Simulation experiment with microcomputer and actual experiment with S101 image processing system both show good results.
1983, 5(5): 280-289.
Abstract:
In this paper, the equations for calculation of the radiation performances on high efficiency double reflector antenna fed by beam waveguide are derived.Using these equations, the performance of the antenna can be predicted, such as the radiation patterns, the peak values of copolarization and depolarization, the factor of half power beam width, the phase loss and so on.These equations have been reformed to meet the requirements of general engineering eomputation. Some engineering computations are made, and some useful conclusions about the antenna are obtained.
In this paper, the equations for calculation of the radiation performances on high efficiency double reflector antenna fed by beam waveguide are derived.Using these equations, the performance of the antenna can be predicted, such as the radiation patterns, the peak values of copolarization and depolarization, the factor of half power beam width, the phase loss and so on.These equations have been reformed to meet the requirements of general engineering eomputation. Some engineering computations are made, and some useful conclusions about the antenna are obtained.
1983, 5(5): 290-302.
Abstract:
In this paper, from the lumped circuit elements point of view, the distribution of gap interaction impedance coefficients of resonant coupled cavity output section of broadband klystrons is analyzed.The following topics are diseussed: 1. the seleetion of equivalent eircuit; 2. the calculation of impedance distribution with given parameters of the lumped eircuit element; 3. the calculation of transfer impedance and microwave eircuit parameters with measured self-impedances.
In this paper, from the lumped circuit elements point of view, the distribution of gap interaction impedance coefficients of resonant coupled cavity output section of broadband klystrons is analyzed.The following topics are diseussed: 1. the seleetion of equivalent eircuit; 2. the calculation of impedance distribution with given parameters of the lumped eircuit element; 3. the calculation of transfer impedance and microwave eircuit parameters with measured self-impedances.
1983, 5(5): 303-312.
Abstract:
A new method of increasing the power capability of microwave FETs by increas-ing the electrode length is proposed. An analytical model with distributed parameters of the structure is derived. A set of equations deseribing the mutual interaetion of voltage and eurrent on the electrodes with the charge current in the active layer of FET is found. This set of basie equations is transformed into coupled mode form. When the electromagnetic coupling is weak enough and in synchronous case, the wave amplification with ultra wide bandwidth occurs. The wave amplitude along the drain electrode system increases linearly with distance, the power output is directly proportional to the active drain electrode length. A broadband power combining exists. In nonsynchronous case, wave amplification shows only a narrow bandwidth. When the electromagnetic coupling cannot be neglected, the wave amplitude grows exponentially along the electrode length, indicating a high gain characteristic. the TW FET can be realized by proper design of the electrode system, and high power output with long life operation results.
A new method of increasing the power capability of microwave FETs by increas-ing the electrode length is proposed. An analytical model with distributed parameters of the structure is derived. A set of equations deseribing the mutual interaetion of voltage and eurrent on the electrodes with the charge current in the active layer of FET is found. This set of basie equations is transformed into coupled mode form. When the electromagnetic coupling is weak enough and in synchronous case, the wave amplification with ultra wide bandwidth occurs. The wave amplitude along the drain electrode system increases linearly with distance, the power output is directly proportional to the active drain electrode length. A broadband power combining exists. In nonsynchronous case, wave amplification shows only a narrow bandwidth. When the electromagnetic coupling cannot be neglected, the wave amplitude grows exponentially along the electrode length, indicating a high gain characteristic. the TW FET can be realized by proper design of the electrode system, and high power output with long life operation results.
1983, 5(5): 313-319.
Abstract:
In this article, we try to summarize the physical modei or plasma induced field emission cathode. Its emission meehanism is related to the presence of cathode spot with detonation of cathode microtip.
In this article, we try to summarize the physical modei or plasma induced field emission cathode. Its emission meehanism is related to the presence of cathode spot with detonation of cathode microtip.
1983, 5(5): 320-323.
Abstract:
A near IR GaP/Ga(1-x)InxP/Ga0.47In0.53As (x:01) photocathode with 0.7-1.65 photoresponse is proposed and designed. The photoemission of the GaP/Ga(1-x)InxP/Ga0.47In0.53As is calculated and eompared with the photoemission of the GaAs photocathode (0.4-0.9m) under night sky (full moon and clear star) irradiation.
A near IR GaP/Ga(1-x)InxP/Ga0.47In0.53As (x:01) photocathode with 0.7-1.65 photoresponse is proposed and designed. The photoemission of the GaP/Ga(1-x)InxP/Ga0.47In0.53As is calculated and eompared with the photoemission of the GaAs photocathode (0.4-0.9m) under night sky (full moon and clear star) irradiation.
1983, 5(5): 324-326.
Abstract:
The relation between the gain G of an optimum pyramidal horn and its aperture size (B/A)=T is derived, and a set of eurves is plotted. With the set of eurves, the design of an optimum pyramidal horn becomes easier.
The relation between the gain G of an optimum pyramidal horn and its aperture size (B/A)=T is derived, and a set of eurves is plotted. With the set of eurves, the design of an optimum pyramidal horn becomes easier.
1983, 5(5): 327-329.
Abstract:
A technology is presented by which silver cream is sintered on a glass substrate so that a compact bright silver layer is formed and at the same time a nickel wire is agglutinated on the glass substrate. The technical process is analysed and the silvernickel interfacial layer is observed by means of Auger electron speetroscopy. The technology is suitable for some specific vacuum devices. Experiments show that a silver layer can firmly combine with nickel wire or mesh.
A technology is presented by which silver cream is sintered on a glass substrate so that a compact bright silver layer is formed and at the same time a nickel wire is agglutinated on the glass substrate. The technical process is analysed and the silvernickel interfacial layer is observed by means of Auger electron speetroscopy. The technology is suitable for some specific vacuum devices. Experiments show that a silver layer can firmly combine with nickel wire or mesh.
1983, 5(5): 330-332.
Abstract:
The capability of heat conduction of the slow wave structure is one of the main obstaeles to the development of the high-frequency high-power helix TWTs. A simple but reliable technological method for obtaining high heat conduction capability and low rf loss is suggested. The method of measurement of the heat conduction capability and the results of this measurement are given also.
The capability of heat conduction of the slow wave structure is one of the main obstaeles to the development of the high-frequency high-power helix TWTs. A simple but reliable technological method for obtaining high heat conduction capability and low rf loss is suggested. The method of measurement of the heat conduction capability and the results of this measurement are given also.
