Patent ID: 9466881
Filing Date: 2016-10-11
CPC Classification: G01C,G01S,H01Q

Claim Text:
1. An apparatus comprising: a receiver to receive a free-space electromagnetic carrier signal from a transmitter with at least one other receiver, signal power of the carrier signal being distributed over a region of coverage of the transmitter per a known spatial distribution; an analyzer to compare an actual spatial distribution of the signal power of the carrier signal in the region of coverage with the known spatial distribution of the signal power of the carrier signal in the region of coverage as the receiver is transported along a trajectory therein independently of another trajectory along which the other receiver is transported, the actual spatial distribution being estimated from samples of the spatial distribution of the signal power, each of which comprising concurrent measurements of the signal power by the receiver and the other receiver, the actual spatial distribution of the signal power being continually re-estimated from additional samples of the spatial distribution of the signal power as the receiver and the other receiver are transported along the trajectory and the other trajectory, respectively; and an interface to alert a user responsive to affirming that a difference between the actual and known spatial distributions of the signal power meets a criterion.