Ultrasonic phased arrays are an emerging technology in nondestructive evaluation (NDE) applications. A phased array is a multi-element piezo-electric device whose elements are individually excited by electric pulses at programmed delay times [1]. Such a delay scheme allows electronically controlled dynamic beam control. One of the advantages of using phased arrays in NDE applications over conve...

A beam-steering antenna based on non-uniform metasurface superstrate and artificial magnetic conductor (AMC), operating at 3.5 GHz, is proposed. The can steer the beam along ? = ?18° 18° with 0° in absence of almost zero scan loss. proposed structure consists a top layer made 20 × grid electrically-small square-shaped metallic pixels while bottom part AMC 5 pixels. radiating element, CPW-fed mo...

In this paper, we designed a sliding waveguide array antenna that can be beam-steered via mechanical manipulation. This reduces the vulnerability of electronic beam-steering radars mounted on ships or aircraft to electromagnetic pulse (EMP) attacks. The design frequency was 9.375 GHz. First, proposed adjust phase difference between arrayed antennas by changing length rectangular using slide. Su...

Abstract--6G networks will be required to support higher data rates, improved energy efficiency, lower latency, and more diverse users compared with 5G systems. To meet these requirements, electrically extremely large-scale antenna arrays are envisioned key physical-layer technologies. As a consequence, it is expected that some portion of future 6G wireless communications may take place in the ...

Modern day Stereotactic treatments require high geometric accuracy of the delivered treatment. To achieve the required accuracy the IGRT imaging isocenter needs to closely coincide with the treatment beam isocenter. An influence on this isocenter coincidence and on the spatial positioning of the beam itself is the alignment of the treatment beam focal spot with collimator rotation axis. The pos...

In smart antenna applications, the adaptive beamforming technique is used to cancel interfering signals (placing nulls) and produce or steer a strong beam toward the target signal according to the calculated weight vectors. Minimum variance distortionless response (MVDR) beamforming is capable of determining the weight vectors for beam steering; however, its nulling level on the interference so...

A novel method of beam steering enables a large field of view and reliable single chip light detection and ranging (lidar) by utilizing a mass-produced digital micromirror device (DMD). Using a short pulsed laser, the micromirrors' rotation is frozen in mid-transition, which forms a programmable blazed grating. The blazed grating efficiently redistributes the light to a single diffraction order...

This paper presents a new approach to calculate the 1– 4th order Doppler parameters for Geosynchronous Synthetic Aperture Radar (Geo-SAR). To get accurate calculation results, the Earth is modeled as an ellipsoid and the relative motion between the sensor in an elliptical orbit and the rotating Earth is analyzed. The J2, J3 and J4 orbital perturbation items and attitude steering are analyzed. I...