Correlator

Claim 2

A correlator for measuring the relative position of two objects by means of radiant energy comprising, an object emitting radiant energy, another object constituting a planar replica thereof positioned at a first selected distance from said object, a detector for detecting radiated energy, said detector including a planar sensing area positioned at a second selected distance from said replica, said replica being smaller than said object in the ratio of said second distance to the sum of said first and second distances, said replica including means directing said emitted radiant energy toward said detector whereby a correlation pattern of radiation intensity is applied to said planar sensing area, the distance of the center of said correlation pattern from the center of the planar sensing area being a measure of the miscorrelation of said replica with said object.

Claim 3

A correlator for measuring the position of an object relative to a substantial replica thereof comprising, a planar replica positioned at a first selected distance from said object, means applying radiant energy derived from said object on said replica, a radiation detector positioned at a second selected distance from said replica, said detector being provided with a sensing face, the scale of said replica being smaller than the scale of said object by the ratio of said second distance to the sum of said first and second distances, said replica being positioned to direct portions of said radiant energy toward said detector, whereby variations of radiation intensity occur at said detector in accordance with the correlation in the position of said object and said replica, and means for sensing the amount and direction of radiation intensity over said sensing face relative to a central point thereof.

Claim 4

A correlator for measuring the position of an object relative to a substantial replica thereof comprising, a planar replica positioned at a first selected distance from said object, means applying radiant energy derived from said object on said replica, a radiation detector positioned at a second selected distance from said replica, said detector being provided with a sensing face, the scale of said replica being smaller than the scale of said object by the ratio of said second distance to the sum of said first and second distances, said replica being positioned to direct portions of said radiant energy toward said detector, whereby variations of radiation intensity occur at said detector in accordance with the correlation in the position of said object and said replica, and means for sensing the amount and direction of radiation intensity over said sensing face relative to a central point thereof.

Claim 5

A correlator for measuring the position of an object relative to the position of a substantial replica thereof comprising, a planar replica positioned at a first selected distance from said object, means applying radiant electromagnetic energy derived from said object to said replica, a detector including a planar sensing area, said detector being positioned at a second selected distance from said replica, said replica being smaller than said object in the ratio of said second distance to the sum of said first and second distances, said planar replica including surface means for directing selected portions of said radiant electromagnetic energy toward said detector whereby variations of electromagnetic radiation intensity fall on said planar sensing area in accordance with a correlation law and depending on the degree of correlation between said object and said replica, and means for sensing variations of said electromagnetic radiation strength over said planar sensing area relative to a central point thereof.

Claim 6

A correlator for measuring the position of an object relative to the position of a substantial replica thereof comprising, a planar replica positioned at a first selected distance from said object, means applying radiant electromagnetic energy derived from said object to said replica, a detector including a planar sensing area, said detector being positioned at a second selected distance from said replica, said replica being smaller than said object in the ratio of said second distance to the sum of said first and second distances, said planar replica including surface means for directing selected portions of said radiant electromagnetic energy toward said detector whereby variations of electromagnetic radiation intensity fall on said planar sensing area in accordance with a correlation law and depending on the degree of correlation between said object and said replica, and means for sensing variations of said electromagnetic radiation strength over said planar sensing area relative to a central point thereof.

Claim 7

A correlator for measuring the position of a substantially flat object relative to a substantial replica thereof comprising, a planar replica of said object, said replica having a surface area designed to direct radiant energy from the portions of the area thereof in amounts which are representative of the variations in intensity of the radiant energy projected from similar portions of the surface of said object, said replica being positioned at a first selected distance from said object, means for moving said replica in a direction parallel to said object, means applying radiant electromagnetic energy derived from said object to said replica, a detector composed of a plurality of independent sensitive elemental areas, said detector being positioned at a second selected distance from said replica, said replica being smaller than said object by a scale ratio equal to the ratio of said second distance to the sum of said first and second distances, said replica including means for directing said radiant energy toward said detector in amounts varying over the planar area of the replica representative of the intensity variation of radiation over the area of said flat object, whereby the correlation pattern peak of radiation intensity variation from said planar replica is centered on said detector to an approximation representative of the degree of correlation of the position of said replica relative to the position of said object.

Claim 8

A correlator for measuring the position of a substantially flat object relative to a substantial replica thereof comprising, a planar replica of said object, said replica having a surface area designed to direct radiant energy from the portions of the area thereof in amounts which are representative of the variations in intensity of the radiant energy projected from similar portions of the surface of said object, said replica being positioned at a first selected distance from said object, means for moving said replica in a direction parallel to said object, means applying radiant electromagnetic energy derived from said object to said replica, a detector composed of a plurality of independent sensitive elemental areas, said detector being positioned at a second selected distance from said replica, said replica being smaller than said object by a scale ratio equal to the ratio of said second distance to the sum of said first and second distances, said replica including means for directing said radiant energy toward said detector in amounts varying over the planar area of the replica representative of the intensity variation of radiation over the area of said flat object, whereby the correlation pattern peak of radiation intensity variation from said planar replica is centered on said detector to an approximation representative of the degree of correlation of the position of said replica relative to the position of said object.

Claim 9

A correlator for measuring the position of a substantially flat object relative to the position of a substantial replica thereof comprising, a planar replica of said substantially flat object, said replica being positioned at a first selected distance from said object, said replica having a surface area which reflects radiant energy from portions of the area thereof in amounts which are representative of the variations in intensity of radiant energy emitted by similar portions of the surface of said object, means applying radiant energy derived from said object to said replica, a detector including a planar radiation-sensitive area composed of a plurality of independent sensitive areas, said detector being positioned at a second selected distance from said replica, said replica being positioned at an angle to reflect radiant energy incident thereon from said object toward said detector, means for adjusting the position of said replica in a direction parallel to the area of said substantially flat object, said adjustment being relative to said detector, said replica being smaller than said object by a scale ratio equal to the ratio of said second distance to the sum of said first and second distances, whereby the correlation pattern peak of radiation intensity variation from said planar replica is positioned on said detector at a distance from a selected point thereof representative of the degree of correlation of the position of said replica relative to the position of said replica relative to the position of said object.

Claim 10

A correlator for measuring the position of a substantially flat object relative to the position of a substantial replica thereof comprising, a planar replica of said substantially flat object, said replica being positioned at a first selected distance from said object, said replica having a surface area which reflects radiant energy from portions of the area thereof in amounts which are representative of the variations in intensity of radiant energy emitted by similar portions of the surface of said object, means applying radiant energy derived from said object to said replica, a detector including a planar radiation-sensitive area composed of a plurality of independent sensitive areas, said detector being positioned at a second selected distance from said replica, said replica being positioned at an angle to reflect radiant energy incident thereon from said object toward said detector, means for adjusting the position of said replica in a direction parallel to the area of said substantially flat object, said adjustment being relative to said detector, said replica being smaller than said object by a scale ratio equal to the ratio of said second distance to the sum of said first and second distances, whereby the correlation pattern peak of radiation intensity variation from said planar replica is positioned on said detector at a distance from a selected point thereof representative of the degree of correlation of the position of said replica relative to the position of said replica relative to the position of said object.

Claim 11

An airborne correlator for measuring the position of a terrain map relative to the position of terrain represented thereby comprising, a map of a selected area of terrain, said map being positioned in an aircraft at a selected altitude above the terrain, said map having a radiant electromagnetic energy reflective surface whose variation of reflectivity over its surface is representative of variation of emission of said radiant electromagnetic energy over the surface of said terrain represented by the map, means applying radiant electromagnetic energy emitted by said terrain to said map reflective surface, and a detector including a planar electromagnetic-radiation-sensitive area including a plurality of independent sensitive areas, said detector being positioned at a selected distance from said map, the attitude of said map reflective surface being such as to reflect radiant electromagnetic energy derived from the terrain and incident upon the map surface toward said detector, said map being of a size such that the ratio thereof with respect to size of the terrain it represents is equal to the ratio of said distance To the sum of said distance and said altitude, whereby the correlation pattern peak of radiation amplitude generated by correlation of said map and said represented terrain is centered on said detector with a centering error representing the correlation error.

Claim 12

An airborne correlator for measuring the position of a terrain map relative to the position of terrain represented thereby comprising, a map of a selected area of terrain, said map being positioned in an aircraft at a selected altitude above the terrain, said map having a radiant electromagnetic energy reflective surface whose variation of reflectivity over its surface is representative of variation of emission of said radiant electromagnetic energy over the surface of said terrain represented by the map, means applying radiant electromagnetic energy emitted by said terrain to said map reflective surface, and a detector including a planar electromagnetic-radiation-sensitive area including a plurality of independent sensitive areas, said detector being positioned at a selected distance from said map, the attitude of said map reflective surface being such as to reflect radiant electromagnetic energy derived from the terrain and incident upon the map surface toward said detector, said map being of a size such that the ratio thereof with respect to size of the terrain it represents is equal to the ratio of said distance To the sum of said distance and said altitude, whereby the correlation pattern peak of radiation amplitude generated by correlation of said map and said represented terrain is centered on said detector with a centering error representing the correlation error.

Claim 13

A correlator in accordance with claim 6, in which said radiant energy is in the visible electromagnetic radiation region.

Claim 14

A correlator in accordance with claim 6 in which said radiant energy is in the infrared electromagnetic radiation region.

Claim 15

A correlator in accordance with claim 6 in which said radiant energy is in the microwave region of electromagnetic wavelengths.

Claim 16

A correlator in accordance with claim 6 including an electromagnetic generator, said generator radiating energy to illuminate terrain beneath said aircraft, whereby the radiant energy derived from the represented terrain constitutes the reflection of the energy illuminating the terrain.

Claim 17

A correlator in accordance with claim 6 in which said radiant energy received from the represented terrain constitutes the natural radiations emitted thereby.