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Feng D.,Science and Technology on Electromagnetic Compatibility Laboratory | Feng D.,China Ship Development And Design Center
2013 5th IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, MAPE 2013 | Year: 2013

Ordinary active frequency selective surface (AFSS) was thought to consist of slots etched on one side of an substrate, with the biasing circuit on the other side. In this paper, a new AFSS without biasing circuit is proposed, the inductive voltage produced by incident wave become bias control signal of the lumped active device. Simulation result shows that the FSS resonant at 3GHz (with tiny insert loss) when the field strength of incident wave is small, then the insert loss of the FSS increase along with the field strength of the incident wave when the field strength is larger than 700V/m, the rejection of 3GHz incident wave increase to 18dB when the incident field strength become 10kV/m. © 2013 IEEE.


Feng D.,Science and Technology on Electromagnetic Compatibility Laboratory | Feng D.,China Ship Development And Design Center
2013 5th IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, MAPE 2013 | Year: 2013

Frequency Selection Surface are employed in a variety of electromagnetic application, such as radomes (terrestrial and airborne), electromagnetic shielding absorbers and antennas. etc, this article discuss a new method of miniaturized FSS, unlike the others, cells of this new FSS is composing two layer of metallic patch with a thin medium between. The distributed capacitance of the periodic cell is formed by the coupling of the two metallic patches in different layers. Simulations of the important design variables are presented and a unit cell size of λ/16 is proposed. In addition, our result also implies that the structure has wide application space include multi-band FSS, polarization rotator etc. based on analysis of three other variations on the periodic structure. © 2013 IEEE.


Feng D.,Science and Technology on Electromagnetic Compatibility Laboratory | Feng D.,China Ship Development And Design Center
Proceedings of 3rd Asia-Pacific Conference on Antennas and Propagation, APCAP 2014 | Year: 2014

In this project, an equivalent circuit model of a miniaturized FSS is proposed, it finds that the calculated result of the equivalent circuit model shows good agreement with the numerical method; this model can be used to optimize Frequency Selective Surface parameters for the desired transmission characteristics. The model can accelerate the optimize procedure a lot. © 2014 IEEE.


Feng D.,Science and Technology on Electromagnetic Compatibility Laboratory | Xiaoguang Wu.,China Ship Development And Design Center
2012 10th International Symposium on Antennas, Propagation and EM Theory, ISAPE 2012 | Year: 2012

Frequency Selection Surface are employed in a variety of electromagnetic application, such as radomes (terrestrial and airborne), electromagnetic shielding absorbers and antennas. etc, this article discuss a new method of miniaturized FSS, unlike the others, cells of this new FSS is composing two layer of metallic patch with a thin medium between. The distributed capacitance of the periodic cell is formed by the coupling of the two metallic patches in different layers. Simulations of the important design variables are presented and a unit cell size of λ/16 is proposed. © 2012 IEEE.


Wen D.-E.,Nanjing Southeast University | Wen D.-E.,Science and Technology on Electromagnetic Compatibility Laboratory | Yang H.,Central China Normal University | Ye Q.,Central China Normal University | And 3 more authors.
Physica Scripta | Year: 2013

In this paper, a broadband metamaterial absorber (MA) based on a multi-layer structure is presented. The advantages of this MA are the small periodic unit size, they are thin, have excellent polarization characteristics and are adaptive for wide angles of oblique incident electromagnetic waves. The unit cell of the broadband MA is composed of three dual-band sub-cells; each presents two resonant frequencies so as to form a wide absorptive spectrum when stacked. The sandwiched dual-band sub-cell is composed of one metallic annular patch and one metallic circular patch each etched on a lossy substrate. The radii of the metallic patches forming each sub-cell are different so as to appear to have different resonant frequencies. In the design of the unit cell there are metallic circular patches and an air layer at the bottom of each sub-cell to form magnetic coupling and avoid coupling between sub-cells. The broadband MA presents good absorptivity above 80% between 8.8 and 10.8 GHz, with a full width at half maximum (FWHM) absorption bandwidth of 2.3 GHz and a relative FWHM absorption bandwidth of 23%. © 2013 The Royal Swedish Academy of Sciences.


Feng D.,Science and Technology on Electromagnetic Compatibility Laboratory | Feng D.,China Ship Development And Design Center
2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012 - Proceedings | Year: 2012

High-power microwave pulse can easily destroy the chip of high-sensitivity electric device (etc. low noise amplifier & Mixer) in the RF channel when it's frequency is in the band of the radar/communication equipment. This article find out that radome make up of FSS(Frequency Selective Surface) loaded with TVS can prevent the high-power microwave pulse penetrating into the radome when the normal EM(electromagnetic) signal can get in/out of the antenna without energy loss. The simulation result shows that the effect of the protective radome is excellent. © 2012 IEEE.


Deng F.,Science and Technology on Electromagnetic Compatibility Laboratory | Xi X.,Science and Technology on Electromagnetic Compatibility Laboratory | Li J.,Science and Technology on Electromagnetic Compatibility Laboratory | Ding F.,China Ship Scientific Research Center
IEEE Antennas and Wireless Propagation Letters | Year: 2015

Most conventional active frequency selective surfaces (AFSSs) are designed with a dc biasing circuit to allow the application of dc biasing voltage across any active component. An innovative method of designing AFSS is here described. It involves using an induced voltage across the surface loading components. This voltage serves as the biasing sign and facilitates control of FSS's transmission properties. The simulated results prove that a passband exists on the FSS at 3.3 GHz when it is exposed to a less intense electric field; when the electric field intensity (EFI) is higher than 70 V/m, the insertion loss of the electromagnetic wave (EMW) increases at 3.3 GHz. When the intensity of the incoming microwave field reaches 5000 V/m, the insertion loss can reach 23 dB. The results of the present experiment were consistent with those of simulations. © 2002-2011 IEEE.


Deng F.,Science and Technology on Electromagnetic Compatibility Laboratory | Yi X.,Science and Technology on Electromagnetic Compatibility Laboratory | Wu W.,Science and Technology on Electromagnetic Compatibility Laboratory
IEEE Antennas and Wireless Propagation Letters | Year: 2013

In this letter, a novel bandpass frequency selective surface (FSS) is proposed. Unlike the traditional FSSs, our building block makes use of a periodic cell with much smaller size than the resonant wavelength. The proposed FSS is composed by two layers of metallic unit cells printed on the substrate. The coupling between parallel patches in different metallic layers can produce the significant distributed capacitance of the FSS; as a result, the size of the FSS unit cell can be decreased to λ/16. Our simulated result shows that the transmission characteristic of the miniaturized FSS is very stable since the relative change rate of resonant frequency is less than 2% with respect to different incident angles from 0° to 45°. The measured results show good agreements with the simulated ones. In addition, our result also implies that the structure has wide application space, based on analysis of three other variations on the periodic structure. © 2013 IEEE.


Huang C.,Science and Technology on Electromagnetic Compatibility Laboratory | Wu X.,Huazhong University of Science and Technology
NDT and E International | Year: 2015

A pulsed eddy current (PEC) testing signal processing method for ferromagnetic material is presented. Without any filtering process that may produce signal distortion, the numerical cumulative integration of the noisy PEC signal is calculated and subsequently fitted to the theoretical model. The model parameter estimation is later applied to quantify the specimen thickness and reconstruct a denoised PEC signal. A comparison is made between the presented method and the former direct-fitting method. The results demonstrate that the presented method improves the testing performance in terms of the detectable thickness range, the probe lift-off distance, and the measuring time. © 2014 Elsevier Ltd. All rights reserved.


Wang D.,Science and Technology on Electromagnetic Compatibility Laboratory | Gao L.,Science and Technology on Electromagnetic Compatibility Laboratory | Zheng S.,Science and Technology on Electromagnetic Compatibility Laboratory
2015 IEEE 6th International Symposium on Microwave, Antenna, Propagation, and EMC Technologies, MAPE 2015 | Year: 2015

In order to study the damage mechanism of PIN diode limiter induced by microwave pulse, basic semiconductor equations based on drift-diffusion model and two-dimensional finite element simulation method were employed to study PIN diode's electric field distribution, carrier concentration and lattice temperature changes under the effect of 2GHz high power microwave. Analysis showed that when it reaches the breakdown threshold, avalanche occurs first in region of the I layer close to the P-I junction. After the avalanche occurs, the electric field magnitude in the I layer declined rapidly. Peak-value electric field appeared separately at the P-I junction and the I-N junction, and these two positions is great point lattice temperature. In the positive half cycle of the microwave pulse, maximum temperature point appears in the center area of I layer. No matter breakdown caused by the negative pulse or injection of a large number of carriers caused by positive pulse, they are both likely to lead to the emergence of PIN diode's permanent physical damage. © 2015 IEEE.

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