相关论文: Feed rotation corrections for antennas having beam…
Recent advancement in next generation reconfigurable antenna and fluid antenna technology has influenced the wireless system with polarization reconfigurable (PR) channels to attract significant attention for promoting beneficial channel…
Heterodyne receivers register the sky signal on either a circular polarization basis (where it is split into left-hand and right-hand circular polarization) or a linear polarization basis (where it is split into horizontal and vertical…
Wireless backhaul communication has been recently realized with large antennas operating in the millimeter wave (mmWave) frequency band and implementing highly directional beamforming. In this paper, we focus on the alignment problem of…
With the increasingly new ultra wide-band applications, antenna researchers face huge challenges in designing novel operational geometries. Mono-pole and quasi-mono-pole antennas are seen to be the most compact and easily incorporate able…
A device performing both the polarization-alignment and the wavelength selection is demonstrated by fabricated device. Waveguides incorporating Bragg gratings for polarization rotation and mode conversion having different widths are placed…
The propagation of guided electromagnetic waves in open elliptical metamaterial waveguide structures is investigated. The waveguide contains a negative-index media core, where the permittivity, $\epsilon$ and permeability $\mu$ are negative…
Very Long Baseline Interferometry (VLBI) astrometry is a well established technique for achieving $\pm10~\mu$as parallax accuracies at frequencies well above 10~GHz. At lower frequencies, uncompensated interferometer delays associated with…
Connected radio interferometers are sometimes used in the tied-array mode: signals from antenna elements are coherently added and the sum signal applied to a VLBI backend or pulsar processing machine. Usually there is no computer-controlled…
A study of band edge phenomena in ridge waveguide magnetophotonic crystals is presented. Normal mode analysis is used to examine the near-band edge and Bragg center-wavelength group velocities and their relation to the polarization. Large…
We consider acoustic wave transmission in non axisymmetric waveguide which consists of cylindrical resonator and two semi-infinite cylindrical waveguides whose axes are shifted relative to the resonator axis and each other by azimuthal…
When performing radio detection of ultra-high energy astroparticles, the planar wavefront model is often used as a first step to evaluate the arrival direction of primary particles. This model estimates the direction by adjusting the…
VLBI astrometry allows coordinates of celestial radio sources to be determined with submilliarcsecond accuracy. In particular, with differential VLBI astrometry, the standard errors of relative positions and proper motions can be as small…
We have studied Very Long Baseline Array (VLBA) polarimetric observations of 8 sources including quasars and BL Lacs at 12, 15, 22, 24 and 43 GHz and high frequency rotation measure ($RM$) maps are presented. We find typical values for the…
Recently, pinching antennas have attracted significant research interest due to their capability to reconfigure wireless channels as well as their array configuration flexibility. This letter focuses on how these features can be used to…
Traditional beam tracking methods have severe performance loss under the high mobility and narrow beam scenario. To alleviate the tracking performance degradation, we propose an adaptive beamwidth control for millimeter wave (mmWave) beam…
Light-matter coupling is investigated by rotating, by an angle \theta, the polarization of linearly polarized microwaves with respect to the long-axis of GaAs/AlGaAs Hall-bar electron devices. At low microwave power, P, experiments show a…
By fitting the classical Rotating Vector Model (RVM) to high quality polarization data for selected radio pulsars, we find the inclination of the magnetic axis to the spin axis, alpha, as well as the minimum angle between the line of sight…
We present 5 GHz space-VLBI observations of the quasar pair B1342+662/B1342+663 that demonstrate the feasibility of phase-reference techniques using an antenna in space. The space-based data were taken by the satellite HALCA, of the…
The design, simulation and measurement of a beam steerable slotted waveguide antenna operating in X band are presented. The proposed beam steerable antenna consists of a standard rectangular waveguide (RWG) section with longitudinal slots…
Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry…