The reconfigurable design problem is to find the element that will result in a sector pattern main beam with side lobes. The same excitation amplitudes apply to the array with zero-phase that should be in a high directivity, low side lobe pencil shaped main beam. Multi-beam antenna arrays have important applications in communications and radar. This paper presents a new method of designing a re...

How much do model errors influence the closed loop performance? This question is investigated for the control problem of designing active damping of vibrations in a viscoelastic cantilever beam. The beam is physically modeled using Fourier transformed Euler-Bernoulli beam equations. For control design the standard LQG technique is employed, and two different finite order models are used. One is...

The requirements for beamforming in high intensity focused ultrasound (HIFU) for tissue destruction are substantially different than those for diagnostic imaging. High numerical aperture and CW efficiency are desirable for tissue destruction, while depth of focus and broadband sensitivity are key to good imaging. When the same transducer must be used for ablation and imaging some compromises mu...

A method for designing near optimal, tapered subarrays for adaptive interference cancellation is proposed. The design method simultaneously produces a complete ordered set of fixed beam definitions, or nonadaptive weight vectors. The designer may choose to implement the first of these if he or she wishes to have exactly adaptive weights. In other words, the digital–adaptive processing is done i...

Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic count...

The Beam Hole Photon Veto counter (BHPV) for the J-PARC KOTO experiment was designed by MC simulation. This detector is required to operate under extremely large flux of neutrons and low energy γs, as placed in the beamline and directly exposed with such particles in the neutral beam. To realize this detector, we proposed an array of Cerenkov counter modules, each of which has a lead sheet as γ...

In this paper, behaviors of photonic crystal (PC) radiative structures and antenna arrays have been compared for two types of uniform and binomial excitations. Appropriate duality has been shown between them. These results can be generalized to other types of excitation and arrangement of photonic crystal radiative arrays such as linear, planar and circular arrays of three dimensional (3D) phot...

Acoustic metasurfaces have been widely explored and attracted great attention for their extraordinary wavefront manipulation abilities. In this paper, we propose a simple acoustic metagrating with periodic grooves that can split normally incident beam into two or three reflected beams. The amplitudes power flows of different beams be manipulated by changing the groove parameters. mirror wave is...

Ground motion at the future JLC detector may affect beam alignment and cause huge luminosity loss. The FEATHER (Feedback AT High Energy Requirements) project addresses this problem by designing a fast intrapulse feedback system that will correct the observed beam offset. Also submitted to the Proceedings of the APP Institute. FEATHER: a fast intra-pulse feedback system for the JLC. Nicolas Dele...

∗ This work is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098. Abstract The Lawrence Berkeley National Laboratory (LBNL) is presently designing and building the 2.5 MeV injector for the Spallation Neutron Source (SNS). The design includes various beam intercepting devices such as beam stops and...