Colinear heterodyne frequency modulator

Claim 2

In a frequency modulating apparatus, the combination of: laser means for providing first oppositely propagating coherent electromagnetic continuous optical waves traveling along a selected path which extends between two mirrors through said laser means; a frequency modulator positioned in the path of the first optical waves and including radio frequency pulsed wave energy beam means for providing an acoustic wave in said frequency modulator whereby the first optical waves are diffracted to produce frequency translated optical waves and whereby the frequency translated optical waves are transmitted along colinear paths angled with respect to the path of the first optical waves; a detector receiver positioned in one of the colinear paths for receiving a first one of the frequency translated optical waves; and means for directing a second one of the frequency translated optical waves towards a target to produce a frequency shift in the second one of the frequency trAnslated optical waves by the target and means for receiving the frequently shifted second one of the frequency translated optical waves reflected from the target, said receiver recombining the frequency shifted second one of the reflected waves with the first one of the frequency translated optical waves.

Claim 3

In a pulse doppler radar frequency modulating system operating at approximately 10.6 microns, the combination of: a first active laser medium comprising a carbon dioxide laser; a first resonant optical cavity having an axis and being positioned about said active laser medium, said cavity having first and second reflectors for stimulating coherent emission from said active laser medium for providing a low power coherent electromagnetic light wave propagating along said axis; a second laser medium; a second optical resonant cavity being positioned about said second laser medium and having an axis colinear with said first cavity axis, said second optical resonant cavity comprising said second reflector and a rotatable reflector for enabling Q-switching of the light wave in said second laser medium to produce an amplification of the light wave emanating from said first active laser medium; a frequency modulator including means for providing an acoustic wave in said frequency modulator; said second reflector being constructed and positioned to transmit the low-power optical wave to said frequency modulator, thereby yielding a low-power diffracted optical beam, and said rotatable reflector positioned in the path of said optical wave for Q-switched retransmission of the optical wave into said frequency modulator to produce therefrom a high powered diffracted optical pulse oppositely directed from the low-power diffracted optical beam; and a photodetector receiver in the path of the low-power diffracted optical beam for reception thereof.

Claim 4

In a pulse doppler radar frequency modulating system operating at approximately 10.6 microns, the combination of: a first active laser medium comprising a carbon dioxide laser; a first resonant optical cavity having an axis and being positioned about said active laser medium, said cavity having first and second reflectors for stimulating coherent emission from said active laser medium for providing a low power coherent electromagnetic light wave propagating along said axis; a second laser medium; a second optical resonant cavity being positioned about said second laser medium and having an axis colinear with said first cavity axis, said second optical resonant cavity comprising said second reflector and a rotatable reflector for enabling Q-switching of the light wave in said second laser medium to produce an amplification of the light wave emanating from said first active laser medium; a frequency modulator including means for providing an acoustic wave in said frequency modulator; said second reflector being constructed and positioned to transmit the low-power optical wave to said frequency modulator, thereby yielding a low-power diffracted optical beam, and said rotatable reflector positioned in the path of said optical wave for Q-switched retransmission of the optical wave into said frequency modulator to produce therefrom a high powered diffracted optical pulse oppositely directed from the low-power diffracted optical beam; and a photodetector receiver in the path of the low-power diffracted optical beam for reception thereof.

Claim 5

A frequency modulating apparatus comprising: a first source of energy for producing first oppositely propagating electromagnetic energy waves at a first frequency traveling along a first axis; a second source of energy for providing non-optical second energy at a second frequency along another axis within a modulating means; said first and second sources positioned with respect to each other so as to permit the first energy waves and second energy to cross at an intersection; and said modulating means positioned at the intersection to cause frequency modulation of the first waves by the non-optical energy for obtaining a pair of frequency translated electromagnetic energy waves oppositely directed respectively to a detector and to a target for frequency shifting thereby and for reflection of the frequency shifted waves to the detector.

Claim 6

A frequency modulating apparatus comprising: a first source of energy for producing first oppositely propagating electromagnetic energy waves at a first frequency traveling along a first axis; a second source of energy for providing non-optical second energy at a second frequency along another axis within a modulating means; said first and second sources positioned with respect to each other so as to permit the first energy waves and second energy to cross at an intersection; and said modulating means positioned at the intersection to cause frequency modulation of the first waves by the non-optical energy for obtaining a pair of frequency translated electromagnetic energy waves oppositely directed respectively to a detector and to a target for frequency shifting thereby and for reflection of the frequency shifted waves to the detector.

Claim 7

A frequency modulating apparatus as in claim 3 wherein said second source comprises an ultrasonic frequency source coupled to said frequency modulator for producing therein an ultrasonic wave at the second frequency.

Claim 8

A frequency modulating apparatus as in claim 3 wherein said modulator diffracts the coherent energy wave into two oppositely directed frequency translated portions for direct transmission of one of the two portions to the target.

Claim 9

A frequency device as in claim 3 wherein said modulator diffracts the coherent energy wave into two oppositely directed frequency translated portions for direct transmission of one of the portions to said detector.

Claim 10

A target detecting method for generating two oppositely directed, colinear electromagnetic wave energy beams, one of the beams having a frequency translation opposite from the frequency translation of the other of the beams, comprising the steps of: directing oppositely propagating electromagnetic continuous wave energy beams into a frequency modulating apparatus, the continuous wave energy beams being directed substantially at the Bragg angle or at a multiple thereof with respect to the frequency modulator; frequency modulating the continuous wave energy beams by radio frequency pulsed wave energy in the frequency modulating apparatus to produce the two oppositely directed, colinear electromagnetic wave energy beams having opposite frequency translations; directing one of the two oppositely directed, colinear electromagnetic wave energy beams toward a moving target to produce a doppler shift of the one beam reflected from the target; and comparing the doppler shifted one beam with the other of the two beams.

Claim 11

A target detecting method for generating two oppositely directed, colinear electromagnetic wave energy beams, one of the beams having a frequency translation opposite from the frequency translation of the other of the beams, comprising the steps of: directing oppositely propagating electromagnetic continuous wave energy beams into a frequency modulating apparatus, the continuous wave energy beams being directed substantially at the Bragg angle or at a multiple thereof with respect to the frequency modulator; frequency modulating the continuous wave energy beams by radio frequency pulsed wave energy in the frequency modulating apparatus to produce the two oppositely directed, colinear electromagnetic wave energy beams having opposite frequency translations; directing one of the two oppositely directed, colinear electromagnetic wave energy beams toward a moving target to produce a doppler shift of the one beam reflected from the target; and comparing the doppler shifted one beam with the other of the two beams.

Claim 14

An object detection method utilizing coherent electromagnetic wave energy beams of opposite frequency translation comprising the steps of: directing oppositely propogating beams of coherent electromagnetic wave energy at a first frequency along a first axis; providing non-optical wave energy along a second axis crossing the first axis at an intersection within a modulating means; modulating the beams by the non-optical energy at the intersection within the modulating means to produce a simultaneous upshifting and downshifting of the first frequency of the oppositely propagating beams of coherent electromagnetic wave energy and, consequently, to produce the coherent electromagnetic wave energy beams of opposite frequency translation and direction; directing one beam of the beams of opposite frequency translation towards an object for frequency shifting of the one beam by the object; obtaining the reflection of the one beam from the object as a reflected and frequency shifted beam; and mixing the coherent electromagnetic wave energy beams and comparing the reflected and frequency shifted beam with the other of the beams of opposite frequency translation.

Claim 15

An object detection method utilizing coherent electromagnetic wave energy beams of opposite frequency translation comprising the steps of: directing oppositely propogating beams of coherent electromagnetic wave energy at a first frequency along a first axis; providing non-optical wave energy along a second axis crossing the first axis at an intersection within a modulating means; modulating the beams by the non-optical energy at the intersection within the modulating means to produce a simultaneous upshifting and downshifting of the first frequency of the oppositely propagating beams of coherent electromagnetic wave energy and, consequently, to produce the coherent electromagnetic wave energy beams of opposite frequency translation and direction; directing one beam of the beams of opposite frequency translation towards an object for frequency shifting of the one beam by the object; obtaining the reflection of the one beam from the object as a reflected and frequency shifted beam; and mixing the coherent electromagnetic wave energy beams and comparing the reflected and frequency shifted beam with the other of the beams of opposite frequency translation.