Energy Selective Filter with Power-Dependent Transmission Effectiveness in Waveguide

Abstract

A novel Energy Selective Filter (ESF) mounted in waveguide is presented based on nonlinear element, which is sensitive to the power intensity of incident wave achieving frequency selection as well as energy selection. The proposed ESF consists of three parts, the middle circuit board with diode loaded, the upper and bottom ground metallic patches. The mechanism of the ESF is analyzed through equivalent circuit model and its performance is investigated numerically and experimentally. According to the waveguide measurement, a shielding effectiveness of 13 dB is achieved in case of high power input and the insertions loss is less than 0.3 dB across the whole frequency range when low power signal inputs. It is a pluggable component in waveguide that could reflect high power signals of specific frequency to protect the following electronic equipment.

Waveguide Energy-Selection-Filter Switch Array

“…Besides, it is manually welded and assembled, the actual size of the prototype cannot be strictly consistent with that of simulation, which affects the distribution capacitance and inductance parameters of the structure. The small change of capacitance could change the resonant frequency of a single unit [28], and then affect the frequency response of the whole structure. The results have verified the nonlinear characteristics of proposed ESFS that the transmission coefficient is dependent on the power intensity of incident wave.…”

“…Compared with other traditional waveguide limiters and filters, the proposed ESFS does not need to change the structure of the original waveguide, that is to say, it is pluggable and replaceable. The isolation effect under high power signal is better than [23] and the frequency bandwidth wider than [28]. Therefore, the ESFS proposed in this paper can provide a different way to protect HPM.…”

“…The resonant frequency is proportional to 1/l, that is to say, inversely proportional to patch size l. That is because the capacitance C 1 and C 2 increase with the patch size. Similarly, the resonant frequency also decreases with the increase of patch distance h. The equivalent circuit value of the single cell has been discussed in our early report [28], which will be used to analyze equivalent circuit with multi-unit structure in this article.…”

“…However, aforementioned component needs to be fixed in the waveguide and cannot be replaced, limiting its application. Recently, we had reported a narrow-band waveguide energy-selective filter with only one unit and one diode, is pluggable and can provide more design freedom [28]. Subsequently, we studied the energy selective surface of multi-element based on the high impedance surface in waveguide, which adaptively adjusts the impedance of waveguide wall according to different power to protect HPM from attack [23].…”

Spatial Wave Control Using a Self-biased Nonlinear Metasurface at Microwave Frequencies

“…For the proposed metasurface that composed of 576 unit cells, the minimum impinging power to switch the state of diodes from off-to-on is calculated 30.06 dBm, therefore, the metasurface at this power as a self-biased nonlinear surface without needs to a complex DC biasing network could switch its functionality from a QWP to a DSWMM. Again, it must be mentioned that at high frequencies for high power illuminations since the carriers injecting rate to the intrinsic layer during the positive cycles is much more than the carriers outgoing rate from the intrinsic layer during the negative cycles, despite the time variations of the induced voltage, the operational status of the diodes would be stable [42].…”