# Preconditions

Backscattered RCS data must be in the UV plane of the local coordinate system or the XY plane of the global coordinate system. Equivalently, the backscattered RCS should be requested in the $\theta \text{'}={90}^{\circ }$ cut. Sub-ranges of the total angular phi range could be used to change the viewing angle.

It is assumed that the image will be centred at the global origin. Thus the down-range (X) and cross-range (Y) should be sufficient to include all the structures / targets relative to the global origin.

The extent and resolution of the ISAR image depend on the frequency range, the number of frequencies, angular range and number of incident angles.