US3701019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alarm system using coded signalling
Assignee: SIGNATRON Inc A CORP OF DE
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Filing: 1970-03-25
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Granted: 1972-10-24
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Expires: 1990-03-25
Abstract
Abstract A signaling system for detecting at a central station a message from a remote location at which one or more different messages can be generated. A coded signal is generated at the remote location and an ''''error'''' uniquely determined by the message to be transmitted is inserted into the coded signal and the altered signal transmitted. A receiver at the central station is arranged to detect the presence of such inserted ''''error'''' so as to correctly identify the message that has been transmitted, whereby such message can be displayed or used to activate an alarm device.
Inventors
- 👤 Charles L Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:31
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/004; H04L1/0056; H04L1/0057
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
200 words
A signaling system comprising means for generating an initial sequence of random information bits: encoding means including means responsive to said generating means for generating a sequence of redundant information bits derived from and bearing a unique relation to said initial sequence of random information bits; said encoding means further including means for producing a cyclicly encoded assembled signal comprising said sequences of random and redundant information bits; means for producing a message signal; means for changing the characteristics of said first encoded assembled signal at a specified bit position thereof in response to said message signal to produce an altered assembled signal having an effective error determined by the changed characteristics at said specified bit position; means for transmitting said altered assembled error signal; means for receiving said altered assembled error signal; error detection means including: decoding means having a configuration for providing operation complementary to said encoding means and being responsive to said received altered assembled signal so as to produce a signal uniquely determined by said effective error in said altered assembled signal; and means responsive to said uniquely determined signal for producing an output signal which indicates said specified bit position to identify said message signal.
Claim 2
Dependent Claim
200 words
A signaling system comprising means for generating an initial sequence of random information bits: encoding means including means responsive to said generating means for generating a sequence of redundant information bits derived from and bearing a unique relation to said initial sequence of random information bits; said encoding means further including means for producing a cyclicly encoded assembled signal comprising said sequences of random and redundant information bits; means for producing a message signal; means for changing the characteristics of said first encoded assembled signal at a specified bit position thereof in response to said message signal to produce an altered assembled signal having an effective error determined by the changed characteristics at said specified bit position; means for transmitting said altered assembled error signal; means for receiving said altered assembled error signal; error detection means including: decoding means having a configuration for providing operation complementary to said encoding means and being responsive to said received altered assembled signal so as to produce a signal uniquely determined by said effective error in said altered assembled signal; and means responsive to said uniquely determined signal for producing an output signal which indicates said specified bit position to identify said message signal.
Claim 3
Dependent Claim
37 words
A signaling system in accordance with claim 1 wherein said message signal generating means includes a plurality of message sources; and means for selecting the output from one of said message sources to produce said message signal.
Claim 4
Dependent Claim
45 words
A signaling system in accordance with claim 1 wherein said receiving means is at a central monitoring station and said transmitting means is at a location remote therefrom, and said signaling system further includes means at said central station for displaying said identified message signal.
Claim 5
Dependent Claim
44 words
A signaling system in accordance with claim 1 wherein said first assembled signal is assembled in accordance with an error correcting code and said characteristic changing means changes the value of said assembled signal so that said detection means produces a unique message signal.
Claim 6
Dependent Claim
40 words
A signaling system in accordance with claim 1 wherein said first assembled signal is assembled in accordance with an error correcting code and said characteristic changing means changes the value of said assembled signal at a single bit position therein.
Claim 7
Dependent Claim
79 words
A signaling system in accordance with claim 4 wherein said first assembled signal comprises a fifteen bit Hamming code signal including eleven random information bits and four redundant information bits and wherein said message signal generating means includes means for generating a plurality of message signals; means for selecting one of said message signals so that the value of said first assembled signal is changed at a different bit position depending upon which message signal is selected for transmission.
Claim 8
Dependent Claim
176 words
A signaling system in accordance with claim 1 wherein said random information bit generating means produces a sequence of random information bits corresponding to the coefficients of an operating polynominal p(x); said redundant information bit generating means includes a plurality of shift register means and exclusive-OR gate means arranged in a configuration corresponding to a generator polynominal g(x), whereby said first assembled signal comprises a sequence of random and redundant information bits corresponding to the coefficients of an output signal p(x).g(x); and said characteristic changing means adds to said first assembled signal a message signal corresponding to a polynominal xi to produce an altered assembled signal f(x) in response to said message signal; and said detection means includes a plurality of shift register means and exclusive-OR gate means arranged to provide a plurality of information bits corresponding to the coefficients of a remainder polynominal r(x) representing the remainder resulting from a division of the received altered assembled signal f(x) by the generator polynominal g(x); said remainder polynominal being uniquely determined in accordance with said message signal.
Claim 9
Dependent Claim
64 words
A signaling system in accordance with claim 1 wherein said transmitting means includes means for modulating said altered assembled signal to provide a modulated transmitted signal; and said receiving means includes means for demodulating said received modulated signal for producing a demodulated altered assembled signal; and means for synchronizing the operation of said detection means with the reception of said received altered assembled signal.
Claim 10
Dependent Claim
31 words
A signaling system in accordance with claim 1 and further including means for providing a signal at said receiving means indicating the absence of a message signal in said transmitted signal.
Claim 11
Dependent Claim
54 words
A signaling system in accordance with claim 9 wherein said determining means further includes a plurality of decision making circuits for producing an indication of the presence or absence of a message signal only when said message signal, or the absence of any said message signal, has been determined for a selected time period.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |