1. Field of the Invention
The present invention relates to location monitoring devices which are used to alert a user when another object or person is located outside a set proximity zone. More specifically, the present invention relates to those location monitoring devices which are compact, portable, and display the relative location of the other person once outside the proximity zone.
2. Description of the Prior Art
U.S. Pat. No. 4,593,273 issued Jun. 3, 1986 to Bernadine O. Narcisse discloses a proximity monitoring device in which a base unit is alerted whenever a mobile unit is outside of a certain range as set by a threshold detector on the mobile unit.
U.S. Pat. No. 3,333,271 issued Jul. 25, 1967 to Stephen J. Robinson et al. discloses a receiver system for measuring the angular direction of propagation of a transmitted frequency relative to the receiver system.
U.S. Pat. No. 4,021,807 issued May 3, 1977 to Jerry W. Culpepper et al. discloses a beacon tracking system in which the location and distance of a beacon can be monitored from a police cruiser.
U.S. Pat. No. 4,785,291 issued Nov. 15, 1988 to Candy C. Hawthorne discloses a proximity detector for monitoring the proximity of a child.
U.S. Pat. No. 4,476,469 issued Oct. 9, 1984 to David R. Lander discloses a locating device for finding commonly lost articles.
U.S. Pat. No. 5,021,794 issued Jun. 4, 1991 to Robert A. Lawrence discloses a personal emergency locator network which may be used to locate a lost child.
U.S. Pat. No. 4,704,612 issued Nov. 3, 1987 to Boy et al. discloses locating transmitter and receiver system for locating a hunting arrow in which the transmitter is located before it is shot. The receiver uses a directional antenna to determine the relative angular position of the receiver relative to the arrow having the transmitter located therein.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.