On Finding the Source of a Signal

If an airplane crashes, an emergency locator transmitter (ELT) is activated. The crash site can then be located by taking bearings on the ELT signal. The statistical problem consists of estimating a two-dimensional location parameter, where the data consist of directional bearings observed, with some error, from several known positions. We develop methods for estimating location for several variations of the basic problem: unidirectional and bidirectional observations, biased observations, and finally, techniques that are insensitive to outliers. These methods can easily be implemented on a portable microcomputer, and seem to perform quite well when applied to some actual data.