Hyperbolic navigation system

Article By:

Peterson, Benjamin B. Formerly, Department of Engineering, United States Coast Guard Academy, New London, Connecticut.

Hartnett, Richard J. Department of Engineering, United States Coast Guard Academy, New London, Connecticut.

Last reviewed:August 2020

DOI:https://doi.org/10.1036/1097-8542.332200

A navigation system that produces hyperbolic lines or surfaces of position by measuring the difference in times of reception (or phase difference) between radio signals from two or more synchronized transmitters. Such systems require the use of a receiver that measures the time difference (or phase difference) between arriving radio signals. Assuming that the velocity of signal propagation is relatively constant across a given coverage area, the difference in the times of arrival (or phase) is constant on a hyperbola having the two transmitting stations as foci (Fig. 1). Therefore, the receiver measuring time or phase difference between arriving signals must be located somewhere along the hyperbolic line of position (LOP) corresponding to that time or phase difference. If a third transmitting station is available, the receiver can measure a second time or phase difference and obtain another hyperbolic line of position. The intersection of the lines of position provides a two-dimensional navigational fix (Fig. 1). Historically, navigators would plot their positions on paper charts that had these hyperbolic lines of position printed on them. For a number of reasons, this practice is no longer common, and the hyperbolic nature of the navigation solution is not as obvious.

The content above is only an excerpt.