Patent US6306914B1 successfully refreshed from Google Patents.
US3824347A
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US
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Voice and data multiplexing system with improved signalling
Assignee: II COMMUNICATIONS CORP
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Filing: 1973-02-01
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Granted: 1974-07-16
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Expires: 1993-02-01
Abstract
Abstract A multiplexing system is provided for use in combination with a common grade telephone voice channel. A first means is provided which during a first mode of operation limits a physical speech band into a first reduced frequency band of a predetermined bandwidth. The bandwidth is less than one-half of the bandwidth of the voice channel and the first band is situated at the low end of the channel. A second means is operative during the first mode of operation for limiting the physical speech band into a second reduced frequency band of a predetermined bandwidth. The second means positions the second band above the first band in the channel. The second band is also less than one-half of the bandwidth of the voice channel. The second means is operative during a second mode of operation for limiting the physical speech band into a third reduced frequency band which is slightly narrower than the bandwidth of the voice channel. A switching means is provided for disabling the first means during the second mode of operation. Means are provided for generating a first signal indicating the use of the first band, and first dialing signals associated with the use of said band and for providing a second signal indicating the use of the second or the third band and second dialing signals associated with the use of said band. Means are also provided for combining the first and second bands, the first and second signals during the first mode of operation and for combining the third band and the second signal during the second mode of operation. The system also comprises means for discriminating between said first and second signals and other signals which may appear in the system, dialing signal discriminating means for discriminating between true dialing signals and other signals which may appear in the system and normalizing means for normalizing the on/off ratio of the dialing signals.
Inventors
- 👤 T Sorber
- 👤 R Unks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:51
CPC Classifications
H; H04; H04Q; H04Q11/00; H04M; H04M11/00; H04M11/06; H04M11/062
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
270 words
In a system for use with a common grade telephone voice channel comprising first means operative for transmitting a first voice signal, second means operative for transmitting a second voice signal, third means for transmitting a first ''''on hook'''' signal when said first means is not operating and for transmitting a first ''''off hook'''' signal and first dialing signals when said first means is operating, fourth means for transmitting a second on hook signal when said second means is not operating and for transmitting a second off hook signal and second dialing signals when said second means is operating, the improvement comprising: first receiving means comprising first discriminating means for discriminating between said first off hook signal and other signals which may exist within said channel, second discriminating means for discriminating between valid dialing signals and other signals which may exist within said channel and first gate means operative in response to the detection of a valid off hook signal by said first discriminating means for enabling said first dialing signals to signal a particular telephone in accordance with the content of said dialing signals and second receiving means comprising third discriminating means for discriminating between said second off hook signal and other signals which may exist within said channel, fourth discriminating means for discriminating between valid second dialing signals and other signals which may exist within said channel and second gate means operative in response to the detection of a valid off hook signal by said third discriminating means for enabling said second dialing signals to signal a particular telephone in accordance with the content of said dialing signals.
Claim 2
Dependent Claim
270 words
In a system for use with a common grade telephone voice channel comprising first means operative for transmitting a first voice signal, second means operative for transmitting a second voice signal, third means for transmitting a first ''''on hook'''' signal when said first means is not operating and for transmitting a first ''''off hook'''' signal and first dialing signals when said first means is operating, fourth means for transmitting a second on hook signal when said second means is not operating and for transmitting a second off hook signal and second dialing signals when said second means is operating, the improvement comprising: first receiving means comprising first discriminating means for discriminating between said first off hook signal and other signals which may exist within said channel, second discriminating means for discriminating between valid dialing signals and other signals which may exist within said channel and first gate means operative in response to the detection of a valid off hook signal by said first discriminating means for enabling said first dialing signals to signal a particular telephone in accordance with the content of said dialing signals and second receiving means comprising third discriminating means for discriminating between said second off hook signal and other signals which may exist within said channel, fourth discriminating means for discriminating between valid second dialing signals and other signals which may exist within said channel and second gate means operative in response to the detection of a valid off hook signal by said third discriminating means for enabling said second dialing signals to signal a particular telephone in accordance with the content of said dialing signals.
Claim 3
Dependent Claim
117 words
The improvement as specified in claim 1 wherein said first discriminating means monitors if said first off hook signal has persisted for a predetermined period of time sufficient to ensure that said off hook signal is a valid off hook signal and wherein said third discriminating means monitors if said second off hook signal has persisted for a predetermined period of time sufficient to ensure that said off hook signal is a valid off hook signal, said first discriminating means enabling said first gate if said first off hook signal is a valid off hook signal and said third discriminating means enabling said second gate if said second off hook signal is a valid off hook signal.
Claim 4
Dependent Claim
60 words
The improvement as specified in claim 1 wherein said second discriminating meand determines if each of said first dialing pulses are of at least a predetermined duration to ensure that each is valid and wherein said fourth discriminating means determines if each of said second dialing signal is of at least a predetermined duration to ensure that each is valid.
Claim 5
Dependent Claim
48 words
The improvement as specified in claim 3 wherein said second discriminating means precludes signals of less than said predetermined duration from being provided to sAid first gate and wherein said fourth discriminating means precludes signals of less than said predetermined duration from being provided to said second gate.
Claim 6
Dependent Claim
48 words
The improvement as specified in claim 4 wherein said first receiving means also comprises a first normalizing means to normalize the signal from said second discriminating means and wherein said second receiving means also comprises a second normalizing means to normalize the signal from said fourth discriminating means.
Claim 7
Dependent Claim
110 words
The improvement as specified in claim 5 wherein said first receiving means also comprises a first tone detector which is operative to provide a first logic signal in response to said first on hook signal, a second logic signal in response to said first off hook signal and first logic signals in response to said first dialing signals and wherein said second receiving means also comprises a second tone detector which is operative to provide a first logic signal in response to said second off hook signal, a second logic signal in response to said second off hook signal, and first logic signals in response to said second dialing signals.
Claim 8
Dependent Claim
107 words
The improvement as specified in claim 6 wherein said first discriminating means comprises first memory means for controlling said first gate and a first pulse forming circuit for providing a pulse to said memory means to result in the enabling of said first gate if said second logic signal exists for a predetermined period of time and wherein said third discriminating means comprises second memory means for controlling said second gate and a second pulse forming circuit for providing a pulse to said second memory means to result in the enabling of said second gate if said second logic signal exists for a predetermined period of time.
Claim 9
Dependent Claim
91 words
The improvement as specified in claim 7 wherein said first discriminating means also comprises a third pulse forming circuit for providing a pulse to said first memory means to result in the disabling of said gate if said first logic signal exists for a predetermined period of time and wherein said third discriminating means also comprises a fourth pulse forming circuit for providing a pulse to said second memory means to result in the disabling of said second gate if said first logic signal exists for a predetermined period of time.
Claim 10
Dependent Claim
172 words
The improvement as specified in claim 8 wherein said second discriminating means comprises first logic means for switching logic states to that of an input signal when actuated by a pulse at an actuating input thereof and a fifth pulse forming circuit forming a pulse a predetermined period of time after said first tone detector changes logic states, the input to said first logic means being coupled to said tone detector and the actuating input of said first logic means being coupled to said fifth pulse forming circuit and wherein said fourth discriminating means comprises second logic means for switching logic states to that of an input signal when actuated by a pulse at an actuating input thereof and a sixth pulse forming circuit for forming a pulse a predetermined period of time after said second tone detector changes logic states, the input to said second logic means being coupled to said second tone detector and the actuating input to said second logic means being coupled to said sixth pulse forming circuit.
Claim 11
Dependent Claim
20 words
The improvement as specified in claim 9 wherein said first and said second normalizing means each comprise a monostable multivibrator.
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) | 1977-07-15 | 1978-01-14 | 1978-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-15 | 1982-01-14 | 1982-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-15 | 1986-01-14 | 1986-07-16 | $7700.00 | Window Closed / Lapsed |