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Detection radar is a great threat and challenge for military target like aircraft in modern war. In order to effectively reduce the radar cross section (RCS) from the object's surface to achieve the stealth performance, a novel graphene absorber based on partial non-periodic plane is presented in this paper. The absorption rate of the proposed graphene absorbing screen is more than 90% in the range...
From EISCAT VHF radar observations it is evident that polar mesosphere summer echoes (PMSE) often show obvious layers. PMSE overshoot describe the effect of dusty plasma parameters on overshoot characteristics curve. In this paper we obtain and compare different PMSE overshoot characteristic curves (OCCs) at 80–85km and 85–90km in one hour respectively, from based on the data observed by EISCAT 224...
In order to meet the higher requirements of the future information warfare on the electronic RF system of tank armored platform, this paper presents that the integrated RF system should be applied to the new armored platform. The system is designed with the method of synthetic aperture; it can complete the functions such as airborne target search, precise tracking, threat assessment, electronic warfare,...
The multipath clutter cancellation, the most computationally demanding part of signal processing in passive bistatic radar (PBR), is a key challenge in real time processing. However the previous Extensive Cancellation Algorithm (ECA) versions have their limitations in parallel implementation. In this paper an advanced version of ECA is proposed for multipath clutter cancellation in passive radar....
A generalized hybrid scheme combining finite element method (FEM) and the method of moments (MoM) accelerated by multilevel fast multipole algorithm (MLFMA) is first presented to investigate scattering from a 3-D dielectric object above a 2-D electrically large dielectric rough surface. The hybrid FEM/ MoM scheme is divided into the FEM region for the object based on Helmholtz's equation and the MOM...
This letter describes a novel Time-Domain Finite-Element Method based second-order Engquist-Majda ABC. In order to improve the accuracy, a specific corner condition is introduced at the corners of the external boundary. For the discretization of time derivatives, the Newmark method is used to obtain an unconditionally stable scheme with the second-order accuracy. Numerical results are presented showing...
Measurement principle and procedure for the antenna noise temperature are represented simply by Y-factor method. Effect of uncertainties for ambient load and low-noise amplifier noise temperature on antenna noise temperature measurement is analyzed, and absolute error equation of antenna noise temperature measurement is derived. At fast, analysis and test examples of antenna noise temperature test...
Based on the Equivalent Current Theory of optical waveguide coupling, the electric field distribution of grating structure and notch groove slit are derived. Beam divergence angle with different grating notch groove and light intensity of non-uniform array antenna structure are numerical simulated. Beam light field background comparison diagram with different notch groove current amplitude and the...
In this paper, the impedance matching and radiation performance of the SIW H-plane horn antenna is improved by the modification of the probe and the adoption of a capacitive post in the feeding structure. The simulation results show that using the capacitive post and the modified probe, the reflection coefficient can be reduced, and the gain of the design can be improved in H-plane in the operation...
Double scattering between building and surrounded environment play an important role in the electromagnetic scattering model of urban. In the past, double scattering of vertical wall and rough surface has been studied, in this paper, a closed form solution based on geometrical optics (GO) between non-vertical wall and rough surface is derived. Physical optics (PO) can also be derived in the same way...
The Feature Selective Validation (FSV) Method has been developed as a standard method to mimic an expert's opinion of concurrence between simulation and measurement datasets. This paper presents a comparison of Scattering from model on the Lake to Target on the Sea. Based on the NRCS curves these datasets should appear trendly and quantitive similar. The objective is to present a basic evaluation...
The broadband microwave propagating characteristics of a novel, large volume, glow-discharge argon plasma is reported in this paper. A large volume, glow-discharge argon plasma was designed and the basic plasma parameters were determined using an Impedans Ltd. Langmuir probe under a variety of conditions. The transmission attenuation was recorded by using S parameters of a vector network analyzer...
Gap waveguide (GW) was investigated to realize low loss millimeter wave (mm-wave) transmission line in recent years. In this paper, groove gap waveguide (GGW) is used to design a W band filter antenna array. A 14 slots antenna array with a center fed structure and a fourth order cavity bandpass filter are designed respectively. Then the method of integration is used in the combining of antenna and...
A wideband loop antenna based on four unit cells of composite right/left-handed transmission line (CRLH-TL) is proposed in this paper. The unit cell is composed of a ladder network with two series capacitors and shunt inductors. The loop antenna based on four-cell nonperiodic CRLH-TL shows wider bandwidth performance when comparing with the periodically loaded loop antenna with the same size. The...
The main factors that influence the performance of the current injection probe is the core and the coil loop. First of all, considering the permeability, the paper analyzes how to choose the suitable core. Then, the methods are proposed to improve the high frequency performance of bulk current injection (BCI) probe. One is to change the way of coil loops which adopt the symmetrical parallel winding...
An efficient TE01-mode generator excited by coaxial-waveguide TEM mode is proposed with high mode purity. Simulations show the generator operating at 35GHz can give a TE01 conversion efficiency of 97.5% and mode purity of 99.8% which higher than the TE01 generator available at present.
An improved type of TEn mode circular polarizer consisting of a rectangular dielectric membrane and a ladder-shaped dielectric transition is proposed. The rectangular membrane is placed at 0=44.9° relative to the axial direction of a circular waveguide rather than 45° theoretically in order to realize a circular polarization, and the transition acts as a impedance-matching role for the purpose of...
Simulations for studying novel high-speed railway millimeter-wave radio propagation channels in urban city are presented in this paper by using verified ray-tracing tool. Based on setups of three antenna beam steering strategies at transceiver, the comparisons among these strategies are given by system feasibility and radio channel characteristics. Numerical results of the simulations are shown to...
Polar Mesosphere Summer Echoes (PMSE) are strong radar echoes that have been observed typically by the VHF radar in summer polar mesosphere and have closely relation with charged dust particles. Theoretical analysis and extensive experimental data show that polar mesosphere summer echoes (PMSE) present some kind of regular periodic changes, such as semidiurnal variations, diurnal variations, day-to-day...
A simulator based on drift-diffusion physics model is used in this paper to study the electro-thermal response of MOSFET under HEMP by setting induced voltage signals to the electrode of the device. The temperature of the MOSFET rises if the amplitude of forward-biased induced signal is greater than threshold of the device and falls down either the induce signal is less than threshold or it is forward-biased...
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