Relative guidance using the global positioning system

A method for directing a guided vehicle to a target location, comprising the steps of:

• furnishing a first global positioning system receiver aligned to receive global positioning signals from a selected constellation of satellites in orbit above the earth;
• furnishing a guided vehicle having a second global positioning system receiver aligned to receive global positioning signals from satellites selected from the same constellation of satellites in orbit above the earth;
• locating a target and converting the location of the target to the frame of reference of the selected constellation of satellites of the global positioning system based on the position measurements of the first global positioning system receiver;
• communicating the position of the target, expressed in the frame of reference of the selected constellation of satellites of the global positioning system, to a navigation system of the guided vehicle;
• the guided vehicle remaining within a sufficiently small operating distance of the position of the first global positioning system receiver at the time of the step of locating and converting, that variations in systematic bias errors between the first global positioning system receiver and the second global positioning system receiver are negligible;
• and
• the guided vehicle proceeding to the target location provided in the step of communicating under control of its navigation system while using the positioning signal derived from the second global positioning system receiver aligned to receive positioning signals from the selected constellation of satellites.

A method for guiding a missile to a target, comprising the steps of:

• furnishing a targeting vehicle having a targeting vehicle global positioning system receiver fixed to receive global positioning signals from a selected constellation of satellites in orbit above the earth;
• furnishing a missile having a missile global positioning system receiver fixed to receive global positioning signals from the same selected constellation of satellites in orbit above the earth;
• the targeting vehicle locating a target with an onboard sensor and converting the location of the target to the frame of reference of the selected constellation of satellites of the global positioning system;
• the targeting vehicle communicating the position of the target, expressed in the frame of reference of the selected constellation of satellites of the global positioning system, to a navigation system of the missile;
• and
• the missile proceeding to the target location under control of its navigation system using the target position communicated from the targeting vehicle and the positioning signal derived from the missile global positioning system receiver fixed to receive positioning signals from the selected constellation of satellites, wherein the missile remains within a sufficiently small operating distance of the position of the targeting vehicle, at the time of the step of locating and converting, that variations in systematic bias errors between the targeting global positioning system receiver and the missile global positioning system receiver are negligible.

A method for directing a guided missile to a target location, comprising the steps of:

• furnishing a first global positioning system receiver aligned to receive global positioning signals from a selected constellation of satellites in orbit above the earth;
• furnishing a guided missile having a second global positioning system receiver aligned to receive global positioning signals from satellites selected from the same constellation of satellites in orbit above the earth;
• locating a target and converting the location of the target to the frame of reference of the selected constellation of satellites of the global positioning system based on the position measurements of the first global positioning system receiver;
• communicating the position of the target, expressed in the frame of reference of the selected constellation of satellites of the first global positioning system, to a navigation system of the guided missile;
• and
• the guided missile proceeding to the target location as communicated by the first global positioning system receiver under control of its guided missile navigation system while using the positioning signal derived from the second global positioning system receiver aligned to receive positioning signals from the selected constellation of satellites.