Stabilization system for airborne scanners

Claim 2

An airborne scanner system including in combination airborne detector means having a plurality of discrete channels for simultaneously scanning a target and producing outputs corresponding thereto; a plurality of variable frequency analogue delay lines respectively disposed for sampling said outputs, each of said delay lines including control means for selectively varying the frequency at which said outputs are sampled whereby the data in each channel corresponding to a particular detector scan angle is simultaneously present at the outputs of said plurality of delay lines; and display means coupled to the outputs of said delay lines for providing a visual image corresponding to said target.

Claim 3

An airborne scanner system as set forth in claim 1 wherein said analogue delay lines are respectively semiconductor charge-transfer-device shift registers.

Claim 4

An airborne scanner system as set forth in claim 2 wherein said frequency control means for each shift register include a voltage controlled oscillator for receiving a variable voltage corresponding to the detector scan angle.

Claim 5

An airborne scanner system as set forth in claim 3 wherein said voltage controlled oscillator is effective to produce a linear variation in the clock rate of its corresponding shift register during each scan of said detector.

Claim 6

An airborne scanner system as set forth in claim 4 wherein said display means comprise a light emitting diode display.

Claim 7

A multichannel airborne scanner system having an output substantially free from aircraft motion and image rotation affects comprising: a multichannel detector for simultaneously producing a plurality of discrete channels of time varying data during each scan of a target, said data including distortion components resulting from aircraft roll and image rotation distortion corresponding to the scan angle of the detector; a first plurality of variable frequency analogue delay lines respectively coupled to the outputs of said discrete channels of data, the frequency of each delay line selectively variable responsive to the frequency of clock signals applied thereto; first frequency control means for producing a plurality of clock signals of variable frequency respectively coupled to each of said first plurality of analogue delay lines, said first frequency control means operable to produce clock signals having a frequency corresponding to the scan angle of said detector whereby the outputs of each of said first plurality of delay lines corresponding to a given scan position occur simultaneously, thereby removing image rotation affects from said detector outputs; a second plurality of variable frequency analogue delay lines coupled to the outputs of said first plurality of delay lines, the frequency of each of said second plurality of delay lines selectively variable responsive to the frequency of clock signals applied thereto; second frequency control means for producing a plurality of clock signals of variable frequency respectively coupled to each of said second plurality of delay lines, said second frequency control means operably responsive to the aircraft position to produce said plurality of clock signals having a frequency corresponding to the aircraft roll position whereby roll distortion is effectively removed from the detector outputs; and display means coupled to the outputs of said second plurality of delay lines for providing a visual image of said target substantially free from distortion.

Claim 8

A multichannel airborne scanner system having an output substantially free from aircraft motion and image rotation affects comprising: a multichannel detector for simultaneously producing a plurality of discrete channels of time varying data during each scan of a target, said data including distortion components resulting from aircraft roll and image rotation distortion corresponding to the scan angle of the detector; a first plurality of variable frequency analogue delay lines respectively coupled to the outputs of said discrete channels of data, the frequency of each delay line selectively variable responsive to the frequency of clock signals applied thereto; first frequency control means for producing a plurality of clock signals of variable frequency respectively coupled to each of said first plurality of analogue delay lines, said first frequency control means operable to produce clock signals having a frequency corresponding to the scan angle of said detector whereby the outputs of each of said first plurality of delay lines corresponding to a given scan position occur simultaneously, thereby removing image rotation affects from said detector outputs; a second plurality of variable frequency analogue delay lines coupled to the outputs of said first plurality of delay lines, the frequency of each of said second plurality of delay lines selectively variable responsive to the frequency of clock signals applied thereto; second frequency control means for producing a plurality of clock signals of variable frequency respectively coupled to each of said second plurality of delay lines, said second frequency control means operably responsive to the aircraft position to produce said plurality of clock signals having a frequency corresponding to the aircraft roll position whereby roll distortion is effectively removed from the detector outputs; and display means coupled to the outputs of said second plurality of delay lines for providing a visual image of said target substantially free from distortion.

Claim 9

A multichannel airborne scanner system as set forth in claIm 6 wherein said first and second plurality of analogue delay lines respectively comprise semiconductor charge transfer device shift registers.

Claim 10

A multichannel airborne scanner system as set forth in claim 7 wherein said first and second frequency control means respectively comprise voltage controlled oscillators.

Claim 11

A multichannel airborne scanner system as set forth in claim 8 wherein said display comprises a light-emitting diode display.

Claim 12

A multichannel airborne scanner system as set forth in claim 7 wherein said first frequency control means is effective to produce a plurality of clock signals respectively having, during each scan of said detector, a linear variation in clock frequency.