Figure 1
From: Upper bounds on position error of a single location estimate in wireless sensor networks
The intersection for a network consisting of three reference nodes and one target node. (a) measurement one has positive error and two others have negative errors. The intersection is nonempty and does not contain the target node position, (b) all measurement errors are positive and the intersection definitely contains the target node position, (c) all measurements have negative errors and the intersection is nonempty and does not contain the target node position, and (d) all measurement errors are negative and the intersection is empty.