NAVSYS High Gain Advanced GPS Receiver (HAGR) uses a digital beam-steering antenna array to provide additional gain in the direction of the GPS satellite signals. This increases the received signal/noise ratio on the satellites tracked and also improves the accuracy of the pseudo-range and carrier-phase observations. The directivity of the digital beams created from the antenna array also reduc...

Beam steering in two dimensions can be achieved using a reflection-mode liquid crystal optical phased array (OPA) with a backplane that has a twodimensional pixel structure. However, current lithographic constraints require a relatively large pixel pitch, limiting two-dimensional OPAs to steering only to milliradian angles. Moderate to large angle two-dimensional steering can also be readily ac...

Production of metrologically accurate interference patterns with subnanometer fidelity requires precise control of beam position and angle. We consider the beam stability requirements for the cases of interference by plane and spherical waves. Interferometers using beamsplitter cubes and diffraction gratings are among the analyzed topologies. The limitations of spatial filtering to remove angul...

An automated liquid column height measurement technique using the total internal reflection of a collimated laser beam from the convex meniscus surface is proposed. This new technique can alleviate the shortcomings of the traditional cathetometer that tends to introduce user bias. Experimental measurements and theoretical predictions have been conducted to examine the detected signal broadening...

Design and measurement results of a beam-steering integrated lens antenna at 77 GHz are presented. An 8-element LTCC aperture coupled patch antenna feed array with a switching network is used to electrically steer the main beam in H-plane. A 100-mm diameter Rexolite (εr = 2.53) lens is simulated and tested. The eccentricity of the lens is optimized in an earlier work with ray-tracing simulation...

We analyze the throughput, delay and energy efficiency performance of space diversity slotted ALOHA when multibeam smart antenna arrays, capable of steering the beams selectively on smaller sectors, are used at the base station receiver. Analytical expressions to establish the effect of diITerent beamwidths, number of beams, beam steering patterns, and beam service times on the achieved perform...

An algorithm suitable for correction to steering of multiple-charge-state beams in heavy-ion linacs operating at high currents has been developed [1]. It follows a fourdimensional minimization procedure that includes coupling of the transverse beam motions. A major requirement is that it obeys the restricted lattice design imposed by the acceleration of multiple-charge-state heavy-ion beams [2]...