Results 311 to 320 of about 101,767 (351)

Electronic beam steering of shock waves

Ultrasound in Medicine & Biology, 1995
Shock-wave generators are now currently used for the treatment of renal stones. In all these generators the focal zone is determined by their geometrical parameters. We propose, for the first time, a piezocomposite shock-wave generator with electronic focusing. The system is composed of a two-dimensional array and its electronic hardware.
D, Cathignol, A, Birer, S, Nachef, J Y, Chapelon   +3 more
openaire   +2 more sources

Agile Nonmechanical Beam Steering

Optics and Photonics News, 2006
The day is coming when engineers will be able to replace mechanical complex gimbal and steering mirror assemblies in electro-optical systems with thin, conformal devices that either have no moving parts or only make use of micro-motion.
openaire   +1 more source

Wideband plasmonic beam steering in metal gratings

Optics Letters, 2012
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 ...
DE CEGLIA, DOMENICO, VINCENTI, MARIA ANTONIETTA, Scalora, M.   +2 more
openaire   +3 more sources

Hydrophone guided transcranial beam steering

The Journal of the Acoustical Society of America, 2001
A new method for focusing ultrasound energy in brain tissue through the skull bone is investigated. The procedure is designed for use with a multielement therapeutic transducer array and a small catheter-inserted hydrophone receiver placed in the brain in order to guide the array’s focus over a volume of tissue about the receiver.
Greg Clement, Kullervo Hynynen
openaire   +1 more source

Adaptive beam steering: RSSI performance

2015 International Conference on Computer, Communications, and Control Technology (I4CT), 2015
Adaptive beam steering antenna has been develop in this research. The proposed antenna is capable to steer the radiation pattern to phi of 0°, 45°, 135°, 225° and 315° angles and theta of 0°, 13°, 15°, 10° and 12°. This could be achieved with the suitable design antenna based on the patch yagi-uda antenna concept with a single radiator and four ...
M. Jusoh, T. Sabapathy, K.N.F. Ku Azir, M. S. Shakhirul, C.B.M. Rashidi, A.K. Rahman   +5 more
openaire   +1 more source

Array imaging with beam-steered data

IEEE Transactions on Image Processing, 1992
The author presents a system model and inversion for the beam-steered data obtained by linearly varying the relative phase among the elements of an array, also known as phased array scan data. The system model and inversion incorporate the radiation pattern of the array's elements.
openaire   +2 more sources

Beam Steering in Anisotropic Metamaterials

Frontiers in Optics 2010/Laser Science XXVI, 2010
We propose tunable anisotropic metamaterials consisting of silver nanorods and dielectric medium for applications to beam steering and demultiplexing. The tunability is achieved by changing the fill fraction and the properties of the dielectric medium.
R. Panchapakesan, G. Venugopal, K. W. Oh, N. M. Litchinister   +3 more
openaire   +1 more source

Beam Steering Antenna Control Technique

MTT-S International Microwave Symposium Digest, 2005
A technique which reduces the requirement for constructing high accuracy phase shifters for steering the main beam in a small (less than 20 elements) linear antenna array is described. The key hardware components are the phase detectors which monitor the phase difference between adjacent radiating elements and a microcomputer to read the phase ...
openaire   +1 more source

Frequency controlled antenna beam steering

1994 IEEE MTT-S International Microwave Symposium Digest (Cat. No.94CH3389-4), 2002
This paper describes and confirms by measurements the principle of operation of a new patent for beam steering of array antennas. The method is particularly suitable when quick continuous beam control is needed. The patent should have the potential to allow simple technical solutions and cost-effective design and manufacturing.
openaire   +1 more source

Dynamic all-optical beam steering

Laser Congress 2024 (ASSL, LAC, LS&C)
We experimentally explore a beam steering system implementing Risley prism and variable magnification beam expander. It adapts to scanning windows dimensions and distances, with a given spatial resolution, enabling scan in several hundreds milliseconds.
Aurélie Hentz, Jean-Louis Gutzwiller, Michel Alassir, Marc Sciamanna   +3 more
openaire   +1 more source