beam width


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Related to beam width: directivity, Band width

beam width

[′bēm ‚width]
(electromagnetism)
The angle, measured in a horizontal plane, between the directions at which the intensity of an electromagnetic beam, such as a radar or radio beam, is one-half its maximum value. Also known as beam angle.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

beam width

beam widthclick for a larger image
The beam width of an antenna is the angle in degrees between the half-power points in the azimuth plane.
The full angular interval in the horizontal plane between the points at which the power radiated from the antenna has fallen to half its maximum value. In practice, the effective beam width may be less than this value and may be altered by use of gain control. The beam width of radar is a measure of its discrimination (i.e., it determines the minimum angular separation that two targets can have and still be resolved). Two targets at the same range whose angular separations at the radar antenna exceed one-half of the beam width between half-power points, generally, will be resolved or distinguishable as two individual targets. The smaller the beam width, the greater the annular resolving power. Beam width may be at different locations through the axis, depending upon the shape of the antenna reflector.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
References in periodicals archive ?
The isolation is near to 50 dB over the frequency range up to 50 GHz for the beam width of 40 [micro]m.
As is shown in Figure 2, the beam width of control laser decreases with the increase of [D.sub.2].
However, there are only a few studies on the wide beam of DRA in the published literature [8, 9], and in these papers, except for the good performance of the beam width, other performances such as impedance bandwidth and the size of the antenna are unsatisfactory.
Finally, the effect of beam width on shear strength is linear as indicated by trend lines for all models except the ANNs model which showed a lower increase rate beyond 700 mm width.
Bazant and Oh [22] based on their experimental results, suggested to use a minimum beam width of three times maximum aggregate size (da) used in testing, as the width of fracture process zone of the concrete is three times maximum size of aggregate.
Compared with LTC-PCMS, the new multifunctional MS enhances the gain and decreases beam width of the antenna in 3dB AR band of 9.12-10.2 GHz.
There are plenty of high-tech bells and whistles, like Active Room Compensation technology, which adjusts sound output to the composition of the room (including furniture placement and your own position relative to the speaker), and Beam Width Control, which lets you direct the sound to a specific spot--or let it blast from all 360 degrees.
The BeoLab 90 offers unique Beam Width Control, which enables to change the width of the sound beam to suit different listening situations.
The unusual thing I did was replace the two landing lights (10-degree beam width)--both in the nose of the cowling--with HID taxi lights (30-degree beam width.) I wanted the wider beam because my problem with night flying was not landing, but it was finding those pesky taxiway exits from the runway.
"Analogous to nanoscale spotlights, the cubic antennas focus light with precise control over direction and beam width," added Sikdar.
Beam Width. In order to measure the effective vertical width of the beam that starts from the cone, appropriate measurements were performed by means of a diode laser and a screen.