Retro-encoded missile guidance system
AssigneeThe United States of America as represented by the Secretary of the Army
InventorsRobert R. Mitchell, Walter E. Miller
Life of this patent
Estimating the term…
Abstract
The retro-encoded guidance system guides a flying object in its flight tod its destination by measuring and correcting the angular displacement of its actual trajectory from the straight line-of-sight to the destination. A beam of infrared light emanating from a beacon on the flying object is received and angularly encoded by retro-encoder located at the launcher prior to being returned to the missile. The incident beam and returned beam travel on optical paths that are parallel to each other but opposite in direction. The angular encoding is achieved by a reticle of the retro-encoder imparting frequency modulation to the incident beam, the degree and phase of the modulation depending on the location on the reticle on which the beam is incident.
Claims7
A retro-encoded guidance system for guiding a flying object to have a more direct trajectory toward its destination after being launched from a launcher, said system comprising:
- a retro-encoder mounted on the launcher;
- a beacon mounted on the flying object, said beacon facing aft and emitting an optical beam to travel via a first optical path to be incident on said encoder, said encoder being comprised of a rotatable-mounted reticle, said reticle selectively passing therethrough a portion of said optical beam impinging thereon, an objective lens to receive said optical beam incident thereon via said first optical path from said beacon and focus said beam onto said reticle, a retro-reflector, a recollimating lens positioned to receive said portion passing through said reticle and re-collimate said portion and further transmit said portion to impinge on said retro-reflector, said reflector being adapted for reflecting an incidend optical beam such that upon reflection, said optical beam travels via a second optical path, said first and second paths being parallel to each other but propagating in opposite directions;
- and a receiver located on the flying object to receive said returned beam via said second optical path and, in response to said returned beam, generate correctional signals sufficient to cause the flying object to move closer to the line-of-sight for a more direct arrival at the destination.
A retro-encoded guidance system for guiding a flying object to have a more direct trajectory toward its destination after being launched from a launcher, said system comprising:
- a retro-encoder mounted on the launcher and adapted for imparting to an incident optical beam angular encoding information indicative of the angle between the trajectory of the flying object and the line-of-sight from the launcher to the destination;
- a beacon mounted on the flying object, said beacon facing aft and emitting an infrared beam of a pre-selected diameter to travel via a first optical path to be incident on said encoder, said encoder being further adapted for returning said beam to the flying object via a second optical path, said first and second paths being parallel to each other but propagating in opposite directions, said encoder having a rotatably-mounted nutated fan-blade reticle composed of reflective blades, an objective lens for receiving said infrared beam emitted by said beacon and focussing said infrared beam to be incident on said reticle, said reticle being positioned at the focal plane of said objective lens and an absorbing surface placed such that any of said infrared beam transmitted through said reticle is incident on and absorbed by said surface;
- and a receiver located on the flying object, said receiver being capable of receiving said returned beam and determining the position of the flying object within the diameter of said beam and generating, in response thereto, corresponding correctional signals that are sufficient to cause the flying object to move closer to the line-of-sight from the launcher to the destination for a more direct impact on the destination.
Dependencies are inferred from the claim text.