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US3242431A Expired / Lapsed US ⏱️ 0.0 years remaining

Phase shift keying communication system

Assignee: Robertshaw Controls Co
•
Filing: 1962-05-04
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Granted: 1966-03-22
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Expires: 1982-05-04
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Abstract

No abstract record available.

Inventors

  • 👤 Cecil A Crafts

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 21:21
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/18; H04L27/20; H04L27/2032; H04L27/2035; H04L27/2042; H04L27/2046; H04L27/22; H04L27/227; H04L27/2275; H04L27/2276

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 195 words
IN A PHASE SHIFT COMMUNICATION SYSTEM FOR TRANSFERRING INFORMATION OVER A DISTANCE IN THE FORM OF A MODULATED CARRIER SHIFTING FROM ONE TO ANOTHER OF THREE EQUALLY SPACED PHASES ACCORDING TO AN INFORMATION SIGNAL, A RECEIVER INPUT STAGE CONNECTED TO PRODUCE AS AN OUTPUT SIGNAL AN AMPLIFIED COPY OF SAID MODULATED CARRIER, A PHASE DECTECTOR STAGE CONNECTED TO SAMPLE SAID OUTPUT SIGNAL DEVELOPED BY SAID RECEIVER INPUT STAGE, A SQUARING CIRCUIT ALSO CONNECTED TO SAMPLE THE OUTPUT SIGNAL PROVIDED BY SAID RECEIVER INPUT STAGE AND DEVELOPE A WAVE-TRAIN OF FLAT-TOPPED PULSES, A DIFFERENTIATING CIRCUIT CONNECTED TO RECEIVE SAID FLATTOPPED PULSES AND PRODUCE A SERIES OF TIME-SPACED VOLTAGE SPIKES RESPONSIVE THERETO, A PARALLEL RESONANT CIRCUIT CONNECTED TO RECEIVE SAID VOLTAGE SPIKES AND PRODUCE A TRIPLE FREQUENCY SINUSOIDAL SIGNAL RESPONSIVE THERETO, A FREQUENCY DIVIDER CONNECTED TO SAID PARALLEL RESONANT CIRCUIT FOR REDUCING TO ONE-THIRD THE FREQUENCY OF SAID SINUSOIDAL SIGNAL MEANS FOR SHIFTING THE PHASE OF SAID REDUCED FREQUENCY SIGNAL RELATIVE TO SAID OUTPUT SIGNAL AND FROM APPLYING THE PHASE SHIFTED SIGNAL AS A PHASE REFERENCE SIGNAL TO SAID DETECTOR STAGE FOR PRODUCING AND OUTPUT DIFFERENT FOR EACH OF THE THREE POSSIBLE RECEIVED PHASES OF MODULATED CARRIER.
Claim 2
Dependent Claim 195 words
IN A PHASE SHIFT COMMUNICATION SYSTEM FOR TRANSFERRING INFORMATION OVER A DISTANCE IN THE FORM OF A MODULATED CARRIER SHIFTING FROM ONE TO ANOTHER OF THREE EQUALLY SPACED PHASES ACCORDING TO AN INFORMATION SIGNAL, A RECEIVER INPUT STAGE CONNECTED TO PRODUCE AS AN OUTPUT SIGNAL AN AMPLIFIED COPY OF SAID MODULATED CARRIER, A PHASE DECTECTOR STAGE CONNECTED TO SAMPLE SAID OUTPUT SIGNAL DEVELOPED BY SAID RECEIVER INPUT STAGE, A SQUARING CIRCUIT ALSO CONNECTED TO SAMPLE THE OUTPUT SIGNAL PROVIDED BY SAID RECEIVER INPUT STAGE AND DEVELOPE A WAVE-TRAIN OF FLAT-TOPPED PULSES, A DIFFERENTIATING CIRCUIT CONNECTED TO RECEIVE SAID FLATTOPPED PULSES AND PRODUCE A SERIES OF TIME-SPACED VOLTAGE SPIKES RESPONSIVE THERETO, A PARALLEL RESONANT CIRCUIT CONNECTED TO RECEIVE SAID VOLTAGE SPIKES AND PRODUCE A TRIPLE FREQUENCY SINUSOIDAL SIGNAL RESPONSIVE THERETO, A FREQUENCY DIVIDER CONNECTED TO SAID PARALLEL RESONANT CIRCUIT FOR REDUCING TO ONE-THIRD THE FREQUENCY OF SAID SINUSOIDAL SIGNAL MEANS FOR SHIFTING THE PHASE OF SAID REDUCED FREQUENCY SIGNAL RELATIVE TO SAID OUTPUT SIGNAL AND FROM APPLYING THE PHASE SHIFTED SIGNAL AS A PHASE REFERENCE SIGNAL TO SAID DETECTOR STAGE FOR PRODUCING AND OUTPUT DIFFERENT FOR EACH OF THE THREE POSSIBLE RECEIVED PHASES OF MODULATED CARRIER.

References Cited (Backward Citations)

US2491810A Cited
US2676245A Cited
US2819339A Cited
US2939914A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-03-21 1969-09-20 1970-03-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-03-21 1973-09-20 1974-03-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-03-21 1977-09-20 1978-03-22 $7700.00 Window Closed / Lapsed

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