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Related papers: Ionospheric dispersion compensation using a novel …

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This paper presents a case study from a single, six-hour observing period to illustrate the application of techniques developed for interferometric radio telescopes to the spectral analysis of observations of ionospheric fluctuations with…

Space Physics · Physics 2014-02-05 Joseph Helmboldt , Huib Intema

A great increase in wireless access rates might be attainable by using the large amount of spectrum available in the millimeter wave (mmWave, 30 - 300 GHz) band. However, due to higher propagation losses inherent in these frequencies, to…

Information Theory · Computer Science 2017-05-02 Jinfeng Du , Reinaldo A. Valenzuela

Solar flare emission at X-ray and extreme ultraviolet (EUV) energies can cause substantial enhancements in the electron density in the Earth's lower ionosphere. It is now become clear that flares exhibit quasi-periodic pulsations with…

In 5G networks, a Radio over Fiber architecture utilizing multicore fibers can be adopted for the transmission of mmwave signals feeding phased array antennas. The mmwave signals undergo phase shifts imposed by optical true time delay…

Applied Physics · Physics 2021-02-10 Thomas Nikas , Evangelos Pikasis , Sotiris Karabetsos , Dimitris Syvridis

Fast and broadband spectrum sensing is an essential component in cognitive radio systems, intelligent transportation systems, electronic warfare systems, etc. However, traditional electronic-based solutions have a trade-off among the…

Vibrations, electromagnetic oscillations and temperature drifts are among the main reasons for dephasing in matter-wave interferometry. Sophisticated interferometry experiments, e.g. with ions or heavy molecules, often require integration…

Millimeter wave (mmW) frequencies between 30 and 300 GHz are a new frontier for cellular communication that offers the promise of orders of magnitude greater bandwidths combined with further gains via beamforming and spatial multiplexing…

Networking and Internet Architecture · Computer Science 2014-04-29 Sundeep Rangan , Theodore S. Rappaport , Elza Erkip

High resolution (~1 arcminute) astronomical imaging at low frequency (below 150 MHz) has only recently become practical with the development of new calibration algorithms for removing ionospheric distortions. In addition to opening a new…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. S. Cohen , H. J. A. Röttgering

We propose the synthesis of frequency dispersion of layered structures based on the design of multi-ordered optical filters using nanocircuit concepts. Following the well known insertion loss method commonly employed in the design of…

Optics · Physics 2017-04-05 Yue Li , Iñigo Liberal , Nader Engheta

We report on slow phase variations of the response of the space-ground radio interferometer RadioAstron during observations of pulsar B0329+54. The phase variations are due to the ionosphere and clearly distinguishable from effects of…

Astrophysics of Galaxies · Physics 2021-07-14 M. V. Popov , N. Bartel , M. S. Burgin , T. V. Smirnova , V. A. Soglasnov

The millimeter wave (mmWave) frequencies offer the potential for enormous capacity wireless links. However, designing robust communication systems at these frequencies requires that we understand the channel dynamics over both time and…

Signal Processing · Electrical Eng. & Systems 2017-12-18 Christopher Slezak , Aditya Dhananjay , Sundeep Rangan

The potential of the millimeter wave (mmWave) band in meeting the ever growing demand for high data rate and capacity in emerging fifth generation (5G) wireless networks is well-established. Since mmWave systems are expected to use highly…

Signal Processing · Electrical Eng. & Systems 2017-10-13 Solmaz Niknam , Balasubramaniam Natarajan , Hani Mehrpouyan

This paper presents novel designs, analysis, and performance of 4-pole and 8-pole microwave and millimeter-wave (MMW) waveguide filters for operation at X and Y frequency bands. The waveguide filters have been designed and analyzed based on…

Signal Processing · Electrical Eng. & Systems 2018-10-04 Ardavan Rahimian

It is shown theoretically that an optical bottle resonator with a nanoscale radius variation can perform a multi-nanosecond long dispersionless delay of light in a nanometer-order bandwidth with minimal losses. Experimentally, a 3 mm long…

Optics · Physics 2015-06-16 M. Sumetsky

For gravitational-wave interferometric detectors, there is a tradeoff between the detector bandwidth and peak sensitivity when focusing on the shot noise level. This has to do with the frequency-dependent propagation phase lag (positive…

Quantum Physics · Physics 2015-11-25 Haixing Miao , Yiqiu Ma , Chunnong Zhao , Yanbei Chen

Resonant metamaterials usually exhibit substantial dispersion, which is considered a shortcoming for many applications. Here we take advantage of the ability to tailor the dispersive response of a metamaterial introducing a new method of…

In this paper, we consider random phase fluctuations imposed during wave propagation through a turbulent plasma (e.g. ionosphere) as a source of additional noise in interferometric visibilities. We derive expressions for visibility variance…

Instrumentation and Methods for Astrophysics · Physics 2015-12-02 H. K. Vedantham , L. V. E. Koopmans

Robust and portable optical clocks promise to bring sub-picosecond timing instability to smaller form factors, offering possible performance improvements and new scenarios for positioning and navigation, radar technologies, and experiments…

Dispersion decomposes compound light into monochromatic components at different spatial locations, which needs to be eliminated in imaging but utilized in spectral detection. Metasurfaces provide a unique path to modulate the dispersion…

Optics · Physics 2021-12-30 Yueqiang Hu , Yuting Jiang , Yi Zhang , Jiajie Lai , Peng He , Xiangnian Ou , Ling Li , Huigao Duan

We study experimentally the nonlinear propagation of short pulses of forward volume spin waves in nanometer-thick YIG films. We show that nonlinearity of the spin system can efficiently counteract dispersion broadening of the pulses,…