Propagation time delay at this kind of surfaces can be simplified as
Hence the propagation time delay is restricted within 0 < [DELTA][tau] < [T.sub.c].
Propagation time delay is relative to the dip angle of the surface, the distance from the surface to the antenna, and the elevation angle of the direct signal.
This vertical distance can be transformed into geometry distance for propagation time delay calculation.
When [theta] < [beta], the propagation time delay of multipath signals decreases with the increase of satellite elevation angles.
[[tau].sub.0] is the propagation time delay from the satellite to the receiver.
Propagation time delays of multipath signals can be demonstrated in Figure 2.
(a) shows propagation time delays of multipath signals produced by horizontal surfaces.