It is an effective approach for reducing antennas'scattering to use frequency selective surface (FSS) as main reflector or subreflector.The measured results are given and discussed. In comparison with ordinary met...It is an effective approach for reducing antennas'scattering to use frequency selective surface (FSS) as main reflector or subreflector.The measured results are given and discussed. In comparison with ordinary metallic refiector antenna, the FSS reflector antenna's radiation properties are maintained basically but its radar cross-section (RCS) is reduced significantly. FSS subrefiector can be more easily applied to practice, but has a little higher RCS level than that of FSS main reflector.展开更多
Passive inter-modulation （PIM） is a form of nonlinear distortion caused by the inherent nonlinearities of the passive devices and components in RF/microwave system. It will degenerate the performance of communicatio...Passive inter-modulation （PIM） is a form of nonlinear distortion caused by the inherent nonlinearities of the passive devices and components in RF/microwave system. It will degenerate the performance of communication system with broad-band channel and high-sensitivity receiver. Therefore, it is necessary to construct a model to simulate this process in order to predict the level of PIM. This paper is aimed at constructing some plate models with one-dimensional and two-dimensional contact nonlinearity sections illuminated by two-tone waves, and calculating the scattered field at a fixed-point in space using time-domain physical optics method. By taking fast Fourier transform （FFT）, we get the spectrum of the scattered field and then analyze the generated PIM products. At the end of this paper, some numerical examples are presented to show the influence rules of the relative factors on PIM. The results indicate the variation of the level of PIM with the number of the nonlinear regions, the nonlinear spacing, and the incident power levels.展开更多
文摘It is an effective approach for reducing antennas'scattering to use frequency selective surface (FSS) as main reflector or subreflector.The measured results are given and discussed. In comparison with ordinary metallic refiector antenna, the FSS reflector antenna's radiation properties are maintained basically but its radar cross-section (RCS) is reduced significantly. FSS subrefiector can be more easily applied to practice, but has a little higher RCS level than that of FSS main reflector.
文摘Passive inter-modulation （PIM） is a form of nonlinear distortion caused by the inherent nonlinearities of the passive devices and components in RF/microwave system. It will degenerate the performance of communication system with broad-band channel and high-sensitivity receiver. Therefore, it is necessary to construct a model to simulate this process in order to predict the level of PIM. This paper is aimed at constructing some plate models with one-dimensional and two-dimensional contact nonlinearity sections illuminated by two-tone waves, and calculating the scattered field at a fixed-point in space using time-domain physical optics method. By taking fast Fourier transform （FFT）, we get the spectrum of the scattered field and then analyze the generated PIM products. At the end of this paper, some numerical examples are presented to show the influence rules of the relative factors on PIM. The results indicate the variation of the level of PIM with the number of the nonlinear regions, the nonlinear spacing, and the incident power levels.
