At the exit point, the beams of these precision modules feature diameters of 1mm and a squint angle
of just 0.05mrad, which equals 5/100mm per metre distance from the target.
He underwent orbital decompression (same procedure as patient 2, with endonasal medial decompression and lateral orbitotomy via coronary access) with an increase of his squint angle
from +20[DELTA] to +120[DELTA].
where [[theta].sub.s] is the squint angle
of the monopulse beam, [[theta].sub.el] and [[theta].sub.az] are the differences of elevation angles and azimuth angles between the tracking axis and target, respectively, and [[theta].sub.A] is the angle difference between the beam maximum of quadrant 1 and target.
Under the condition of small squint angle
, the beam center approximates the zero Doppler direction and [[eta].sub.c] [approximately equal to] 0, [[theta].sub.r,c] [approximately equal to] 0.
where [f.sub.a] = 2v sin [theta]/[lambda] is the Doppler frequency, v is the speed of the radar, [theta] is the squint angle
, [B.sub.a] is the processed Doppler bandwidth, [G.sub.r] is the azimuth receiving antenna pattern, k is an integer, [G.sub.t,b] and [G.sub.t,j] indicate the azimuth transmitting antenna patterns for the aft and fore directions, respectively, and [f.sub.dc,b] and [f.sub.dc,j] are the Doppler centroids for backward and forward imaging.
Thus, it should be an accuracy-optimal imaging method and can process SAR data regardless of the bandwidth, beamwidth and squint angle
In this figure, t is the slow time, O the start point, v the SAR platform velocity, and [alpha] the squint angle
. A target denoted by P([r.sub.0], [x.sub.0]) is located in the fixed scene with velocity [v.sub.r] in the slant range direction and [v.sub.a] in the azimuth direction.
Azimuth invariant Azimuth variant Transmitter Receiver Transmitter Receiver Velocity in x 190 m/s 190 m/s 190 m/s 155.8 m/s direction Velocity in y 0 m/s 0 m/s 0 m/s 60.0 m/s direction Squint angle
30[degrees] 30[degrees] 30[degrees] 30[degrees] Bistatic 15237 m 13010m centriod range Range bandwidth 80 MHz 80 MHz Baseline 10519 m 10519m
In some cases further surgery may be required, however in the experience of the authors a small reduction in squint angle
is often enough to resolve symptoms or deformity such that the patient is satisfied with the outcome.
To reduce the system complexity and the requirement of INU measurement precision, the DBS technique, which can construct unfocused radar images at a high squint angle
and in a large scanning field, has been implemented in many airborne PD radar systems.
The main outcome measures were the reduction of the distance/near disparity, the squint angle
at near and at distance, and adduction and abduction measured with the Kestenbaum Limbus test, whichever is available.
In the spotlight and sliding spotlight modes, the time-variant squint angle
inevitably leads to an extension of the azimuth spectrum [4, 5].