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The distribution model of targetpsilas RCS fluctuation and the verification method of the distribution model are studied. The probability distribution of chaff cloudspsila RCS is fitted based on the dynamic measurement data, and the goodness of fit is verified by chi2 verification. Some problem is indicated to select and apply the verification method goodness of fit, which can be used for the test...
The main study of this paper has two aspects. The one is to give an EMC (electromagnetic compatibility) test of WSN (wireless sensor network) used in spacecraft. The other is to test the performance of networks and give a method of frequency allocation. Through these studies, EMC solution and frequency allocation of WSN were got, which can guide to solve the problem of EMC of WSN in spacecraft.
In this paper, we present a theory for the problem of electromagnetic field coupling to a transmission line. Through the numerical calculation, some important coupling characters of external field and transmission lines are elicited. As airborne antennas are strong radiation sources, this paper figures out some methods to control electromagnetic interference of transmission lines according to antennaspsila...
An electromagnetic environment testing system is introduced in this paper. From the point of design philosophy, hardware design is presented and overall design of the software is detailed, as well as its characteristics, respectively. Compared with traditional instruments, the proposed testing system has prominent superiorities in data-processing, manoeuvrability, scalability and cost-effectives.
This paper proposes a troubling diagnosing system for analyzing signal integrity and describes a complete architecture for the system with the crucial software for scanning and controlling. The software is developed with the software LabVIEW 8.5 from the National Instruments. The paper also describes the implementation of the data processing and displaying the radiation graph. Moreover, the result...
In this paper, we designed an amplifier based on the transistor ATF 34143 from Agilent. Networks of input and output with appropriate I/O matching were designed through the ADS design software in order to match the impedance of input and output to 50 Ohm. In addition, special optimizations on noise figure and transmission gain were conducted. To suppress the harmonic, various circuits including LC...
Test of radiation pattern for on-board installed antennas is a difficult and very necessary. This paper by the testing method is the analysis of mission systems on the basis of actual needs and consideration to facilities, place, and other objective conditions, step by step, level by level test pattern of installed antenna. First, testing pattern of antenna in free-space, and then in the open field...
This paper proposes a predistortion linearizer to reducing the third and fifth order intermodulation products in RF power amplifier. Power amplifier linearity has been improved by independently controlling the amplitudes and phases of the third order (IMD3) and fifth order (IMD5) intermodulation distorted products, which are generated by using low frequency second order intermodulation components...
A statistical analysis approach, Monte Carlo (MC) method, which is applied to predict the reliability of a receiver, is presented in this paper. The model of amplitude modulated communication system is built in ADS. An approximation for the output signal-to-noise of nonlinear receiver system is given when the input consists of a carrier signal modulated and noise. Probabilistic models based on the...
With the development of the complexity of the electromagnetic environment in the battlefield, the careful check in the complex electromagnetic environment, which is simulated to the actual battle, is strongly needed for the weapon system. This paper shows the authorpsilas own perspective on the problem of complex electromagnetic environment modeling and how to definite radiation power of simulator.
A major problem of the superheterodyne receivers is their response to the undesired frequencies, such as harmonic, image frequency signal. In this paper, special attention is paid to the image frequency interference. In order to analysis the effect of the image frequency signal to the superheterodyne, a behavioural model of a superheterodyne receiver of altimeter is presented and its electromagnetic...
The active decoy environment of anti-radiation weapon face is introduced, and the position between the radar and the decoy is analyzed. The new way of distinguish multiple source signal by turning PRSpsila antenna is given. Then the feasibility and the limitation are analyzed based on the discussing and testing.
This paper presents numerical analysis to the transient grounding resistance of grounding conductor under pulsed discharging current using parallel FDTD algorithm based on domain decomposition method and MPI library. It is found that the adopted parallel strategy is feasible by comparing the result of serial FDTD computing with the proposed method. The parallel FDTD algorithm provides an efficient...
Chaotic Colpitts oscillating circuit has a broader spectrum characteristic than other chaotic circuits and the complicated bifurcation exhibits rich nonlinear dynamical behaviours. By introducing the normalized state equation, the parameters estimation equation is derived. According to the design requirements of the frequency, the parameter expressions of the main circuit elements are worked out....
Load effect of our developed reverberation chamber is investigated at calibration stage. The influence of receiving antenna, transmit antenna and EUT is analyzed and evaluated according to the measurement data. Load effect calibrations with different receiving antenna positions, transmit antenna positions, and EUT positions are measured carefully. It is indicated that transmit antenna positions, and...
In this paper, an EMP simulator with absorbing stuff is designed. Firstly, the EMP simulator is analyzed according to the circuit. Secondly, the Finite-Difference Time-Domain (FDTD) method is used to model electromagnetic field of effective work space of the EMP simulator accurately. This work will offer theory direction of simulatorpsilas optimized design.
In this paper, a bounded-wave EMP simulator is introduced. The finite-difference time-domain (FDTD) method is used to model electromagnetic field at working region produced by the bounded-wave EMP simulator accurately. And this numerical analysis method is feasible from the compare of numerical result with experiment result.
A case of three-conductor lines is analyzed. The currents in multiconductor transmission lines (MTL) are solved from MTL equation; then, electric dipole sequences and mirror methods are used to estimate the total radiated emissions (RE) induced by these currents. The simulations show that RE of MTL is nonlinear to the one of single circuit. The electric field intensity of MTL is about 1~3 dB smaller...
The application of the visual anechoic chamber system was discussed. A test was designed to validate the effects of the system used in EMI testing. The results were shown that the average level of the ambient cancelled mode was 11.323 dBmuV / m and the effects were influenced by the distance between the device antenna and the background antenna. The coherence of the two antennas may be another factor...
This work mainly aims at the study of experiment about coupling effects of single-chip system under electromagnetic pulse (EMP). The results show that the coupling degree of the connected lines to the pulse field and the characters of the EMP have notable influences on the interference peak value.
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