The value for the reference latitude ([[phi].sub.1] = 33.79[degrees]) of the simple Conic projection in Table 2 is significantly different from that of the Martini map (31.88[degrees]) with interchange of the values resulting in errors of 100-200 km.
The parameters are much the same as before except that the projection parameter [[lambda].sub.0] (Eq 3), the longitude of the central meridian, replaces [[phi].sub.1] (the standard parallel of the Conic projection) as a parameter to estimate.
1 & 2 easily suggest that European cartographers were still using the simple Conic projection for regional maps in the mid-latitudes.
Accordingly, displacements near the ground track from nearby points might be well-approximated by displacements near the equator of an oblique conic projection (where the oblique equator is locally tangent to the ground track).
Assuming zero Doppler effect, when the satellite orbits at instant t, the geometric relation of the conformal conic projection that is tangent to the central line of the side-looking region is shown as in Figure 4, and the angle between the direction of satellite orbit and the x axis is:
Suppose B([phi]', [lambda]') is an arbitrary point in the side-looking region, then the conformal conic projection corresponding to the new equator is: