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US5610748A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical space communication apparatus sending main signals and an auxiliary signal for controlling the intensity at the receiver

Assignee: Canon Inc
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Filing: 1995-04-03
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Granted: 1997-03-11
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Expires: 2015-04-03
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Abstract

Abstract An optical space communication apparatus comprises a transmitter and a receiver. The transmitter has a main signal generator for producing a main signal, an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of the main signal, a combiner for combining the main signal with the auxiliary signal, an electro-optical converter for converting a combined signal of the main signal and the auxiliary signal into a light signal, and a transmission optical system for transmitting the light signal formed in light beam. The receiver has a reception optical system for receiving the light signal in light beam and a photo-electric converter for converting the light signal into an electric signal. The receiver further has a separator for separating the electric signal converted by the photo-electric converter into a main signal and an auxiliary signal, and an auxiliary signal detector for detecting the auxiliary signal separated by the separator.

Inventors

  • 👤 Tetsuo Sakanaka
  • 👤 Yasuhiro Takahashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:05
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/11; H04B10/114

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 203 words
An optical space communication apparatus comprising: a transmitter having a main signal generator for producing a main signals an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of said main signal, a combiner for combining said main signal with said auxiliary signal, an electro-optical converter for converting a combined signal of said main signal and said auxiliary signal into a light signal, and a transmission optical system for transmitting said light signal in a light beam; and a receiver for receiving the light signal in the light beam, said receiver comprising: (i) a photodetector for detecting a part of the light beam so as to detect a positional deviation of light beam; (ii) a photo-electric converter for converting the light signal into an electric signal, said photoelectric converter including an avalanche photodiode as a light receiving element; (iii) a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; (iv) an auxiliary signal detector for detecting the auxiliary signal separated by said separator; and (v) a control circuit for controlling a multiplication factor of said avalanche photodiode using a detection output signal of said auxiliary signal detector.
Claim 2
Dependent Claim 203 words
An optical space communication apparatus comprising: a transmitter having a main signal generator for producing a main signals an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of said main signal, a combiner for combining said main signal with said auxiliary signal, an electro-optical converter for converting a combined signal of said main signal and said auxiliary signal into a light signal, and a transmission optical system for transmitting said light signal in a light beam; and a receiver for receiving the light signal in the light beam, said receiver comprising: (i) a photodetector for detecting a part of the light beam so as to detect a positional deviation of light beam; (ii) a photo-electric converter for converting the light signal into an electric signal, said photoelectric converter including an avalanche photodiode as a light receiving element; (iii) a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; (iv) an auxiliary signal detector for detecting the auxiliary signal separated by said separator; and (v) a control circuit for controlling a multiplication factor of said avalanche photodiode using a detection output signal of said auxiliary signal detector.
Claim 3
Dependent Claim 41 words
An optical space communication apparatus according to claim 1, wherein said receiver has an amplifier for amplifying the main signal separated by said separator, a gain of said amplifier being controlled with a detection output signal of said auxiliary signal detector.
Claim 4
Dependent Claim 27 words
An optical space communication apparatus according to claim 1, wherein said receiver has a level meter for monitoring a detection output signal of said auxiliary signal detector.
Claim 5
Dependent Claim 55 words
An optical space communication apparatus according to claim 1, wherein said main signal generator has a multiplex modulator for multiplexing a plurality of channels of video signals to supply a multiplex signal as a main signal to said transmitter, and said receiver has a multiplex demodulator for demodulating the main signal separated by said separator.
Claim 6
Dependent Claim 116 words
An optical space reception apparatus for receiving a light signal in a light beam, comprising: a photodetector for detecting a part of the light beam so as to detect a positional deviation of the light beam; a photo-electric converter for converting said light signal into an electric signal, said photo-electric converter including an avalanche photodiode as a light receiving element; a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; an auxiliary signal detector for detecting the auxiliary signal separated by said separator; and a control circuit for controlling a multiplication factor of said avalanche photodiode using a detection output signal of said auxiliary signal detector.
Claim 7
Dependent Claim 116 words
An optical space reception apparatus for receiving a light signal in a light beam, comprising: a photodetector for detecting a part of the light beam so as to detect a positional deviation of the light beam; a photo-electric converter for converting said light signal into an electric signal, said photo-electric converter including an avalanche photodiode as a light receiving element; a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; an auxiliary signal detector for detecting the auxiliary signal separated by said separator; and a control circuit for controlling a multiplication factor of said avalanche photodiode using a detection output signal of said auxiliary signal detector.
Claim 8
Dependent Claim 41 words
An optical space reception apparatus according to claim 5, wherein said receiver has an amplifier for amplifying the main signal separated by said separator, a gain of said amplifier being controlled with a detection output signal of said auxiliary signal detector.
Claim 9
Dependent Claim 27 words
An optical space reception apparatus according to claim 5, wherein said receiver has a level meter for monitoring a detection output signal of sand auxiliary signal detector.
Claim 10
Dependent Claim 25 words
An optical space reception apparatus according to claim 5, wherein said receiver has a multiplex demodulator for demodulating the main signal separated by said separator.
Claim 11
Dependent Claim 199 words
An optical space communication apparatus comprising: a transmitter having a main signal generator for producing a main signal, an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of said main signals a combiner for combining said main signal with said auxiliary signal, an electro-optical converter for converting a combined signal of said main signal and said auxiliary signal into a light signal, and a transmission optical system for transmitting said light signal in a light beam; and a receiver for receiving said light signal in the light beam said receiver comprising: (i) a photodetector for detecting a part of the light beam so as to detect a positional deviation of said light beam; (ii) a photo-electric converter for converting said light signal into an electric signal; (iii) a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; (iv) an amplifier for amplifying said main signal separated by said separator; and (v) an auxiliary signal detector for detecting the auxiliary signal separated by said separator, wherein a gain of said amplifier is controlled by a detection output signal of said auxiliary signal detector.
Claim 12
Dependent Claim 199 words
An optical space communication apparatus comprising: a transmitter having a main signal generator for producing a main signal, an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of said main signals a combiner for combining said main signal with said auxiliary signal, an electro-optical converter for converting a combined signal of said main signal and said auxiliary signal into a light signal, and a transmission optical system for transmitting said light signal in a light beam; and a receiver for receiving said light signal in the light beam said receiver comprising: (i) a photodetector for detecting a part of the light beam so as to detect a positional deviation of said light beam; (ii) a photo-electric converter for converting said light signal into an electric signal; (iii) a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; (iv) an amplifier for amplifying said main signal separated by said separator; and (v) an auxiliary signal detector for detecting the auxiliary signal separated by said separator, wherein a gain of said amplifier is controlled by a detection output signal of said auxiliary signal detector.
Claim 13
Dependent Claim 27 words
An optical space communication apparatus according to claim 9, wherein said receiver has a level meter for monitoring a detection output signal of said auxiliary signal detector.
Claim 14
Dependent Claim 56 words
An optical space communication apparatus according to claim 9, wherein said main signal generator has a multiplex modulator for multiplexing a plurality of channels of video signals to supply a multiplex signal as a main signal to said transmitter, and wherein said receiver has a multiplex demodulator for demodulating the main signal separated by said separator.
Claim 15
Dependent Claim 111 words
An optical space reception apparatus for receiving a light signal in a light beam, comprising: a photodetector for detecting a part of the light beam so as to detect a positional deviation of the light beam; a photo-electric converter for converting said light signal into an electric signal; a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; an amplifier for amplifying said main signal separated by said separator; and an auxiliary signal detector for detecting the auxiliary signal separated by said separator, wherein a gain of said amplifier is controlled by a detection output signal of said auxiliary signal detector.
Claim 16
Dependent Claim 111 words
An optical space reception apparatus for receiving a light signal in a light beam, comprising: a photodetector for detecting a part of the light beam so as to detect a positional deviation of the light beam; a photo-electric converter for converting said light signal into an electric signal; a separator for separating the electric signal converted by said photo-electric converter into a main signal and an auxiliary signal; an amplifier for amplifying said main signal separated by said separator; and an auxiliary signal detector for detecting the auxiliary signal separated by said separator, wherein a gain of said amplifier is controlled by a detection output signal of said auxiliary signal detector.
Claim 17
Dependent Claim 27 words
An optical space reception apparatus according to claim 12, wherein said receiver has a level meter for monitoring a detection output signal of said auxiliary signal detector.
Claim 18
Dependent Claim 25 words
An optical space reception apparatus according to claim 12, wherein said receiver has a multiplex demodulator for demodulating the main signal separated by said separator.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-03-10 2000-09-09 2001-03-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-03-10 2004-09-09 2005-03-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-03-10 2008-09-09 2009-03-11 $7700.00 Window Closed / Lapsed

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