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Wave scattering from a cylinder with a tensor impedance surface is investigated based on the Lorentz-Mie theory. A practical example of such a cylinder is a subwavelength metallic rod with helical dielectric-filled corrugations. The…

We consider Wood anomalies in diffraction spectrum from two-dimensional dielectric periodic grid embedded in a surrounding media. The grid is of subwavelength thickness, and diffraction of wave having S-polarization is investigated in the…

Optics · Physics 2019-05-14 Ekaterina Efremova , Sergey Perminov , Sergey S. Vergeles

In this letter, a single-layer dual-band flexible conformal filtering endfire antenna is presented. The proposed antenna is based on two co-designed folded dipoles (FDs) working at two frequencies, where the lower-frequency FD acts as a…

Systems and Control · Electrical Eng. & Systems 2025-09-26 Fan Qin , Runkai Song , Chao Gu , Wenchi Cheng , Steven Gao

Dual sideband (2SB) receivers are well suited for the spectral observation of complex astronomical signals over a wide frequency range. They are extensively used in radio astronomy, their main advantages being to avoid spectral confusion…

Instrumentation and Methods for Astrophysics · Physics 2018-05-17 Ricardo Finger , Patricio Mena , Nicolas Reyes , Rafael Rodriguez , Leonardo Bronfman

Spatio-spectral selectivity, the capability to select a single mode with a specific wavevector (angle) and wavelength, is imperative for light emission and imaging. Continuous band dispersion of a conventional periodic structure, however,…

Deep spectral-line surveys in the mm and sub-mm range can detect thousands of lines per band uncovering the rich chemistry of molecular clouds, star forming regions and circumstellar envelopes, among others objects. The ability to study the…

Instrumentation and Methods for Astrophysics · Physics 2015-11-18 R. Finger , F. P. Mena , A. Barishev , A. Khudchenko , R. Rodriguez , E. Huaracan , A. Alvear , J. Barkhof , R. Hesper , L. Bronfman

In long-baseline interferometry, bandwidth smearing of an extended source occurs at finite bandwidth when its different components produce interference packets that only partially overlap. In this case, traditional model fitting or image…

Instrumentation and Methods for Astrophysics · Physics 2013-08-07 Régis Lachaume , Jean-Philippe Berger

An analog, low-profile and shielded spectrum analyzer is proposed for operation at mm-wave frequencies around the 60 GHz band based on a novel side-fire Leaky-Wave Antenna (LWA) configuration. The proposed side-fire periodic LWA is…

Applied Physics · Physics 2021-09-15 Daniel J. King , Mohamed K. Emara , Shulabh Gupta

One highly desirable function of a diffraction grating is its ability to deflect incident light into a specific diffraction order with near-perfect efficiency. While such asymmetry can be achieved in a variety of ways, e.g., by using a…

We propose to achieve joint detections of frequency and direction of arrival in wideband using single sensor based on an active metasurface with programmable transmission states of pass and stop. By integrating two PIN diodes with the…

Applied Physics · Physics 2022-10-25 He Li , Yun Bo Li , Wang Sheng Hu , Sheng Jie Huang , Jia Lin Shen , Shi Yu Wang , Tie Jun Cui

The detection of inclined air showers (zenith angles $\theta \gtrsim 65^\circ$) with kilometer-spaced radio-antenna arrays allows measuring cosmic rays at ultra-high energies ($E \lesssim 10^{20}\,\mathrm{eV}$). Radio and particle detector…

High Energy Astrophysical Phenomena · Physics 2024-10-11 Felix Schlüter , Tim Huege

The multi-beam measurement system plays a crucial role in ocean mapping and underwater terrain detection. By simultaneously transmitting multiple beams, the system can accurately receive sound waves reflected from the seabed, providing more…

Numerical Analysis · Mathematics 2024-07-12 Chuangqi Li , Yuhang Wang , Fan Hu

At millimeter-wave frequencies, diffuse scattering from rough surfaces is an important propagation mechanism. Including this mechanism in radio propagation modeling tools,such as ray-tracing, is a key step towards realizing accurate…

Signal Processing · Electrical Eng. & Systems 2021-06-16 Stefanos Bakirtzis , Takahiro Hashimoto , Costas D. Sarris

We have developed a two-beam waveguide-type dual-polarization sideband-separating SIS receiver system in the 100-GHz band for {\it z}-machine on the 45-m radio telescope at the Nobeyama Radio Observatory. The receiver is intended for…

Diffraction of a surface wave on a rectangular wedge with impedance faces is studied using the Sommerfeld-Malyuzhinets technique. An analog of Landau's bypass rule in the theory of plasma waves is introduced for selection of a correct…

Optics · Physics 2014-03-25 Igor A. Kotelnikov , Vasily V. Gerasimov , Boris A. Knyazev

Programmable metasurfaces promise a great potential to construct low-cost phased array systems due to the capability of elaborate modulation over electromagnetic (EM) waves. However, they are in either reflective or transmissive mode, and…

Signal Processing · Electrical Eng. & Systems 2024-12-09 Xudong Bai , Longpan Wang , Yuhua Chen , Xilong Lu , Fuli Zhang , Jingfeng Chen , Wen Chen , He-Xiu Xu

Electromagnetic scattering bounds on subwavelength structures play an important role in estimating performances of antennas, RFID tags, and other wireless communication devices. An appealing approach to increase a scattering cross-section…

We report absolutely calibrated measurements of diffuse radio emission between 90 and 190 MHz from the Experiment to Detect the Global EoR Signature (EDGES). EDGES employs a wide beam zenith-pointing dipole antenna centred on a declination…

Instrumentation and Methods for Astrophysics · Physics 2016-10-25 Thomas. J. Mozdzen , Judd. D. Bowman , Raul. A. Monsalve , Alan. E. E. Rogers

Wavefront shaping enables targeted delivery of coherent light into random-scattering media, such as biological tissue, by constructive interference of scattered waves. However, broadband waves have short coherence times, weakening the…

Multiple Mach-Zehnder interferometers are constructed using fiber-Bragg grating couplers, y-branches, silicon waveguides, and/or broadband splitters in silicon on insulator strip waveguides to test the effect of variation in waveguide…

Optics · Physics 2025-07-03 Cael Warner
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