fan beam


Also found in: Medical.

fan beam

See antenna.

fan beam

[′fan ‚bēm]
(electromagnetism)
A radio beam having an elliptically shaped cross section in which the ratio of the major to the minor axis usually exceeds 3 to 1; the beam is broad in the vertical plane and narrow in the horizontal plane.
A radar beam having the shape of a fan.

fan beam

fan beam
Pencil-beam antenna pattern.
fan beam
Fan-beam antenna pattern.
A fan-shaped radar beam, broad in the vertical plane and narrow in the horizontal plane. A fan beam allows only the measurement of the azimuth angle. Typically, a fan beam in aircraft surveillance radar is 1° to 2° in azimuth and 20° to 40°, or broader, in elevation.
References in periodicals archive ?
Key words and phrases: Fan beam tomography, sampling.
The essential bandregion for the fan beam transform of an essentially bandlimited function was determined in [8, 11].
In this article we will use analytic and numerical techniques to compute the essential bandregion for the kernels used in two well-known fan beam CT reconstruction algorithms[9].
This explains the reasonable results which are obtained when the algorithm is applied at the sampling density sufficient for the recovery of the fan beam data.
Thus, the discrete computation of the continuous integral transform necessarily requires either a resampling of the the fan beam projection data or a finer data acquisition.
It is natural to use the fan beam parameterization for lines in [R.
The goal in fan beam tomography is to reconstruct f within [absolute value of x] [less than or equal to] p with as much resolution as possible from discrete samples of Df.
In order to achieve a desired resolution in the reconstructed image, the fan beam transform must be sampled at an appropriate density.
This is due to the fact that daily fan beam CTs have the same consistent CT numbers as any diagnostic CT scanner, and are just as suitable for highly accurate dose calculation.
The gantry houses a linear accelerator, which delivers photon radiation in the shape of a fan beam as the ring is turning.
TESTING; Rachel chooses her spot as the male fan gets ready for his date with destiny; TEASING; The sexy singer inches towards her lucky victim as he begins to grin broadly; TASTING; The fan beams with delight as Rachel plants her tongue on his cheek
Figure 4 shows the concept of a track-while-scan (TWS) radar using two fan beams.