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US3723745A Expired / Lapsed US ⏱️ 0.0 years remaining

Radiant source tracker independent of non-constant irradiance

Assignee: National Aeronautics and Space Administration
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Filing: 1971-12-28
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Granted: 1973-03-27
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Expires: 1991-12-28
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Abstract

Abstract A tracker of a radiant source is disclosed, comprising a sectored matrix of detectors whose output voltages correspond to their respective levels of irradiance. The voltages are each sampled during a variable length period and the resulting samples are shaped into triangular samples by an integration process. They are supplied to a demodulator which provides an output corresponding to the difference of the time-voltage product of appropriate combinations of the samples. This output after filtering represents the angle of incidence on the detectors with respect to a central axis. The triangular samples are also supplied to a demodulator whose output is an AGC voltage which is a function of the sum of the time-voltage integrals of the triangular samples. This AGC voltage is supplied to a pulse width modulator whose output controls the period of the voltage sample which is taken from each detector.

Inventors

  • 👤 J Fletcher
  • 👤 F Campbell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 11:21
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/78; G01S3/782; G01S3/783; G01S3/784

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 113 words
A source-of-energy tracker comprising: first and second energy detectors for converting energy received from said source about a first axis to first and second outputs respectively as a function of the received energy; sampling means for sampling said first and second outputs to provide samples of said outputs; output means responsive to said samples for providing an output signal which is a function of the relationship between pairs of samples, each pair including one sample of said first output and a second sample of said second output; and control means responsive to said samples for controlling the duration of each sampling of said first and second outputs as a function of said samples.
Claim 2
Dependent Claim 113 words
A source-of-energy tracker comprising: first and second energy detectors for converting energy received from said source about a first axis to first and second outputs respectively as a function of the received energy; sampling means for sampling said first and second outputs to provide samples of said outputs; output means responsive to said samples for providing an output signal which is a function of the relationship between pairs of samples, each pair including one sample of said first output and a second sample of said second output; and control means responsive to said samples for controlling the duration of each sampling of said first and second outputs as a function of said samples.
Claim 3
Dependent Claim 64 words
The arrangement as recited in claim 1 wherein said output means include means for providing said output signal as a function of the difference of the time-voltage characteristics of each pair of samples, and said control means include demodulator means for providing a control signal whose amplitude is a function of the sum of time-voltage characteristics of samples of said first and second outputs.
Claim 4
Dependent Claim 50 words
The arrangement as recited in claim 2 wherein said sampling means includes means for providing rectangularly shaped samples of said first and second outputs of durations controlled by said control means and shaping means responsive for converting said rectangularly shaped samples to samples of lower amplitudes but equal time-voltage properties.
Claim 5
Dependent Claim 24 words
The arrangement as recited in claim 3 wherein said shaping means convert said rectangularly shaped samples into triangularly shaped samples of corresponding equal areas.
Claim 6
Dependent Claim 50 words
The arrangement as recited in claim 1 wherein said control means include means for controlling said sampling means to successively sample said first and second outputs during two successive equal duration periods, the durations of said periods being a function of said samples to which said control means is responsive.
Claim 7
Dependent Claim 119 words
The arrangement as recited in claim 5 wherein said sampling means include means for combining said samples of said first and second outputs into a sequence of samples, with alternate samples in said sequence being from the same output and said output means include means for providing said output signal as a function of the difference between each pair of successive samples in said sequence, and said control means being responsive to said sequence, and said control means being responsive to said sequence of samples for providing a control signal whose amplitude is a function of said samples in said sequence, and pulse width means responsive to said control signal for controlling the sampling duration as a function thereof.
Claim 8
Dependent Claim 71 words
The arrangement as recited in claim 6 wherein each output is a direct-current (DC) voltage and said output means include means for providing a difference between each pair of two successive voltage samples as a function of the time-voltage characteristics thereof, and said control means include demodulator means for integrating said samples in said sequence to provide said control signal, with an amplitude which is a function of the integrated samples.
Claim 9
Dependent Claim 23 words
The arrangement as recited in claim 7 wherein said sampling means include shaping means for shaping each of said samples in said sequence.
Claim 10
Dependent Claim 33 words
The arrangement as recited in claim 8 wherein each output sample is of substantially constant amplitude during the entire duration thereof and said shaping means include means for integrating each constant amplitude sample.
Claim 11
Dependent Claim 45 words
The arrangement as recited in claim 9 wherein said demodulator means integrate said samples to provide an output voltage which is a function of the time-voltage integral of said samples, said pulse width means being responsive to said output voltage for controlling said sampling duration.
Claim 12
Dependent Claim 139 words
A tracker for tracking a source of energy and for providing a tracking error signal which is a function of the angle of incidence of the energy from said source, comprising; first and second energy detectors for converting energy received from said source to first and second signals whose amplitudes are related to the energy detected by said first and second detectors, respectively; sampling means for providing a sequence of samples of said first and second signals, alternate samples in said sequence being of the sample signal; output means responsive to said succession of samples for providing an error signal whose amplitude is a function of the time-amplitude difference of a pair of adjacent samples in said sequence; and control means responsive to said succession of samples for controlling the durations of the samples provided by said sampling means.
Claim 13
Dependent Claim 139 words
A tracker for tracking a source of energy and for providing a tracking error signal which is a function of the angle of incidence of the energy from said source, comprising; first and second energy detectors for converting energy received from said source to first and second signals whose amplitudes are related to the energy detected by said first and second detectors, respectively; sampling means for providing a sequence of samples of said first and second signals, alternate samples in said sequence being of the sample signal; output means responsive to said succession of samples for providing an error signal whose amplitude is a function of the time-amplitude difference of a pair of adjacent samples in said sequence; and control means responsive to said succession of samples for controlling the durations of the samples provided by said sampling means.
Claim 14
Dependent Claim 79 words
The arrangement as recited in claim 11 wherein said control means include a demodulator means for providing a control signal whose amplitude is a function of the time integral of the samples in said sequence, and means responsive to a succession of clock pulses and to said control signal for controlling said sampling means to sample said first and second signals during appropriate pulse periods respectively, the sampling period being a function of the amplitude of said control signal.
Claim 15
Dependent Claim 26 words
The arrangement as recited in claim 12 further including means for shaping the samples in said sequence, into corresponding samples of equal areas and lower amplitudes.
Claim 16
Dependent Claim 55 words
The arrangement as recited in claim 12 wherein said sampling means comprises first and second samplers for sampling said first and second signals respectively during periods controlled by said control means, means for combining the samples from said first and second samplers, said control means including means for controlling the sampling periods of said samplers.
Claim 17
Dependent Claim 25 words
The arrangement as recited in claim 14 further including means for shaping the samples in said sequence, into corresponding samples with more constant time bases.

References Cited (Backward Citations)

US3418478A Cited
US3479604A Cited
US3521071A Cited
US3671748A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-03-26 1976-09-25 1977-03-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-03-26 1980-09-25 1981-03-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-03-26 1984-09-25 1985-03-27 $7700.00 Window Closed / Lapsed

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