Mobile tracking and positioning system

A self-contained, portable, mobile tracking and positioning unit for locating a target by triangulation wherein the target broadcasts a radio signal in a region on the surface of the earth which lacks a fixed positioning reference for participating in the triangulation, said positioning unit comprising, in combination:

• a positioning determination device for determining the position of said mobile tracking and positioning unit;
• a direction finder for determining the direction of origin of said broadcast radio signal;
• a two-way communication system for transmitting position information determined from said positioning determination device and direction information determined by said direction finder and for receiving position information and direction information from a remote station;
• and
• a computer for processing said determined position and direction information and said received position information and direction information to locate said target.

A method utilizing triangulation for simultaneously tracking a plurality of mobile targets in a region devoid of a fixed positioning reference that participates in the triangulation, said method comprising:

• providing a plurality of mobile tracking stations including at least first and second mobile stations adapted to transit said region wherein at least two of said tracking stations cooperatively provide mobile position references for locating a plurality of targets by triangulation,
• initiating broadcast of a radio signal from said targets in response to the occurrence of an initiation event at said targets;
• determining the direction of origin of said radio signals from each of said plurality of targets relative to said first mobile station;
• substantially simultaneously with the determination of the direction origin of said radio signals relative to said first mobile station:
• a) determining the instantaneous position of said first mobile station at or above the surface of the earth;
• b) transmitting said instantaneous position and said direction of origin from said first mobile station to said second mobile station;
• c) determining the instantaneous position of said second mobile station;
• d) determining the direction of origin of said radio signals broadcast by said targets at said second mobile station;
• and
• subsequently triangulating said positions of said targets at said second mobile station from said positions of said first and second mobile stations and said respective directions of origin of said radio signals from said targets to said first and second mobile stations.

A tracking system for locating or tracking a mobile target by triangulation in a region that lacks a fixed participating navigation reference in the vicinity of said target, said system comprising:

• first and second mobile tracking stations adapted for transgressing said region in the vicinity of said target and for cooperatively providing instantaneous position references for locating a target by triangulation;
• a transmitter disposed at said target for broadcasting a communication signal in response to an initiation event;
• said first mobile tracking station further including a position determination unit utilizing a navigation reference external of said region for determining a first instantaneous position indicative of the position of said first mobile tracking station while transiting the vicinity of the target, a bearing determination unit including a receiver for receiving the communication signal from said target and for determining a first target bearing indicative of the relative direction to said target from said first mobile tracking station on the basis of said communication signal, and a transmitter unit for transmitting said first target bearing information and said first instantaneous position of the first tracking station;
• said second mobile tracking station further including a receiver for receiving said first target bearing and said first instantaneous position transmitted by said first mobile tracking station, a position determination unit utilizing a navigation reference external of said region for determining a second instantaneous position indicative of the position of said second mobile tracking station while transiting the vicinity of the target, a second bearing determination unit adapted for determining a second target bearing indicative of the relative direction to said target from said second tracking station on the basis of said communication signal transmitted from said target transmitter;
• and
• a processor for analyzing said first and second instantaneous positions of said first and second mobile tracking stations and said first and second target bearings thereby to ascertain by triangulation the exact position of said target.

A tracking system for locating or tracking a mobile target by triangulation in a region that lacks a fixed navigation reference in the vicinity of said target for participating in the triangulation, said system comprising:

• a) first and second mobile tracking stations adapted for transgressing said region in the vicinity of said target;
• b) a transmitter disposed at said target for broadcasting a communication signal in response to an initiation event;
• c) said first mobile tracking stations further including a position determination unit utilizing a navigation reference external of said region for determining the instantaneous position of said first mobile tracking station while transiting the vicinity of the target in said region, a bearing determination unit including a receiver for receiving the communication signal from said target and for determining target bearing information indicative of the relative direction to said target from said first mobile tracking station in response to receipt of said communication signal from said target transmitter, and a transmitter unit for transmitting target bearing information and said instantaneous position of the first tracking station;
• d) said second mobile tracking station further comprising a position determination unit utilizing a navigation reference external of said region for determining the instantaneous position of said second mobile tracking station while transiting the vicinity of the target in the region, a bearing determination unit for determining target bearing information indicative of the relative direction of said target from said second tracking station in response to receipt of said communication signal from said target transmitter, and a transmitter unit for transmitting said target bearing information and the instantaneous position of said second tracking station;
• and
• e) a processor for analyzing the instantaneous positions of said first and second mobile tracking stations and the bearing information transmitted from said first and second mobile tracking stations thereby to ascertain by triangulation the exact position of said target.