In this letter, we present a non-mechanical 2D beam-steering system suitable for optical wireless communication. Steering is achieved using polarization gratings combined with nematic liquid crystal cells operating as voltage-controlled shifters. These steering elements are holographic diffuser matched to the discrete angles of grating, enabling continuous angular coverage. Beam-steering also u...

We demonstrate controllable light deflection in thick metal gratings with periodic subwavelength slits filled with an active material. Under specific illumination conditions, the grating becomes nearly transparent and acts as a uniform optical phased-array antenna where the phase of the radiating elements is controlled by modifying the index of refraction of the material that fills each slit. T...

The 430 MHz radar system of the Arecibo Observatory (AO) possesses one of the largest power-aperture products in the world. The aperture is effectively 200-300 m and the peak power is approximately 2.5 MW. Designed originally for ionospheric and radio astronomy purposes, the A 0 is built into a natural bowl in the Puerto Rican terrain and is operated by the National Astronomy and Ionosphere Cen...

We extend the phase modulation method by in-plane diffractions from plane wave incidence to point source of surface plasmon polariton (SPP). A well-defined SPP focus is successfully realized from a point source under the diffraction by a carefully designed nanohole array, which is easy to layout in the future integrated optical circuits. With this method, the SPP Airy beam and finite plane wave...

Defense applications ofspace-borne laser radar require a sensor that can point to a large number of targets in rapid succession and over a wide field of regard. By using a fullaperture, mechanically steered flat mirror, the requirements for high-acceleration beam steering can be met. Three alternative mirror structures were designed and their perfonnance was evaluated through computer simulatio...

The NLC linac train-by-train feedback system is designed to stabilize the beam trajectory, but is also a valuable element in the strategy for emittance preservation. New simulations employ improved strategies [1], allowing beam steering to be performed significantly less often than without the feedback system. Additional simulations indicate that the linac feedback can contribute towards succes...

We demonstrate a 16-channel, independently tuned waveguide surface grating optical phased array in silicon for two dimensional beam steering with a total field of view of 20° x 14°, beam width of 0.6° x 1.6°, and full-window background peak suppression of 10 dB.

A technique is described for non-destructive measurement and monitoring of the steering offset of the electron and positron beams at the interaction point of the SLC, based on using stripline beam-position monitors to measure the centroid of one beam as it is deflected by the opposing beam. This technique is also expected to provide diagnostic information related to the spot rise of the micron-...

We introduce a new method for beam steering in ultra-wide bandwidth arrays. The approach avoids the need for tunable microwave delays by using lag synchronization in a linear array of locally coupled chaotic oscillators. Steering is controlled by tuning the natural frequency of the oscillators and is analytically equivalent to first order to using explicit delay elements. Using chaotic rf circu...