In this figure, t is the slow time, O the start point, v the SAR platform velocity, and [alpha] the squint angle
In squinted spotlight mode, the aliased azimuth spectrum is not only caused by azimuth beam steering but also by the squint angle
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.
High squint angle
can improve the flexibility and extend application fields of SAR.
Classic chirp scaling algorithm is an efficient focusing algorithm to process the raw data with a low squint angle
without any interpolations.
An airborne simulation experiment in high squint mode with a squint angle
of 40[degrees] is designed and the processing result of real X-band SAR data is shown in Section 4.
The high squint angle
and the diving of platform motion lead to the deeper coupling of range and azimuth of SAR echoes which makes SAR imaging more difficult.
Beside the effect of curved trajectory, the large orbit height will result in large observation swath (single beam 400 km-500 km), and the earth rotation will result in un-ignorable squint angle
By ignoring higher order terms and defining the instantaneous squint angle
[theta] (u) = [tan.
Furthermore, [DELTA]y dependent on the squint angle
was significantly improved by the proposed method.