High-power microwave filters and frequency selective surfaces exploiting electromagnetic wave tunneling through ϵ-negative layers

Abstract

In this paper, we experimentally investigate the phenomenon of electromagnetic wave tunneling through ϵ-negative (ENG) metamaterial layers surrounded by double-positive layers. Initial experiments are conducted by using a rectangular waveguide, which operates below its cutoff frequency to emulate an ENG layer. This ENG layer is then sandwiched by two dielectric substrates with relatively high dielectric constants and it is shown that the entire setup acts as a classical microwave filter with a second-order bandpass response. The power handling capability of this filter is examined experimentally using a high-power magnetron source with a frequency of 9.382 GHz, a pulse duration of 1 μs, and a peak power of 25 kW. Based on the results of this experiment, two methods for improving the power handling capability of these multi-layer structures are proposed. In particular, it is demonstrated that emulating the ENG layers with thin perforated metallic sheets with sub-wavelength holes significantly enhances their peak power handling capability. A prototype of such a device is designed, fabricated, and experimentally characterized and it is demonstrated that it can handle extremely high peak power levels. The results presented in this work are expected to be useful in designing microwave filters and frequency selective surfaces that can handle extremely high peak power levels.

A Dual-Frequency Quasi-Optical Output System for a THz Gyro-Multiplier

“…Hence, the designed FSS is capable of handling the high-power THz output from this gyro-multiplier. For other cases where much higher output power levels are involved, the methods of breakdown prevention by using nonresonant elements [10] or layered structures [34] in the FSSs can be considered.…”

Angular-stable and polarization-independent frequency selective structure with high selectivity

“…V C 2013 AIP Publishing LLC. Bandpass frequency selective surfaces with high selectivity are widely used in various applications of diplexer/ beamsplitter, 1,2 terahertz sensing, 3 thermophotovoltaic spectral control, 4 and power transmission, 5,6 etc. In such applications, it is usually required that a bandpass frequency selective surface can realize a stable in-band/out-of-band filtering response with respect to the incident angle and polarization of an incoming electromagnetic plane wave.…”

Subwavelength three-dimensional frequency selective surface based on surface wave tunneling

“…As a matter of fact, the essential function of a band-pass space filter is to guide wave propagating through, therefore the structure for such purpose does not have to be limited to waveguide or transmission lines as have been realized. We notice that there is coplanar waveguide band-pass filter, which has been constructed using planar surface structured waveguide [18,19]. The surface waveguide filter can be realized by simple metallic frames.…”