US5475691A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voice activated date rate change in simultaneous voice and data transmission
Assignee: DELAWARE RADIO TECHNOLOGIES LLC
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Filing: 1993-11-15
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Granted: 1995-12-12
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Expires: 2013-11-15
Abstract
Abstract A simultaneous voice and data modem performs "voice-activated" data rate changes to improve the transmission quality of the voice signal. In particular, when the simultaneous voice and data modem detects that a local telephone set has gone "off-hook," the simultaneous voice and data modem selects a signal space with a lower symbol density, which, although resulting in fewer bits per symbol, provides for a higher quality voice transmission.
Inventors
- 👤 Joseph Q. Chapman
- 👤 Kurt E. Holmquist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:59
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/0001; H04L1/0015; H04L1/0017; H04M; H04M11/00; H04M11/06; H04L1/0002; H04L1/0003; H04L1/0023; H04L1/0025; H04L1/0036; H04L1/0039; H04L27/00; H04L27/32; H04L27/34; H04L27/345; H04L27/3461; H04L27/3477; H04M11/062; Y; Y02; Y02D; Y02D30/00; Y02D30/50
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
88 words
A method for use in data communications equipment, the method comprising the steps of: selecting a signal space as a function of the detection of an analog signal; selecting symbols from the selected signal space as a function of an applied data signal; providing a resultant signal, where the resultant signal represents the selected symbols when no analog signal is detected and represents the addition of a respective signal point to each one of the selected symbols when the analog signal is detected; and transmitting the resultant signal.
Claim 2
Independent Claim
88 words
A method for use in data communications equipment, the method comprising the steps of: selecting a signal space as a function of the detection of an analog signal; selecting symbols from the selected signal space as a function of an applied data signal; providing a resultant signal, where the resultant signal represents the selected symbols when no analog signal is detected and represents the addition of a respective signal point to each one of the selected symbols when the analog signal is detected; and transmitting the resultant signal.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the analog signal is a voice signal.
Claim 4
Dependent Claim
18 words
The method of claim 2 wherein the detection of the voice signal is provided by an off-hook signal.
Claim 5
Independent Claim
159 words
A method for changing a data rate comprising the steps of: selecting a first signal space when no off-hook signal is detected; transmitting a data signal at a first data rate, where the data signal is represented by a stream of data symbols selected from the first signal space, the data symbols having k bits per symbol; selecting a second signal space when an off-hook signal is detected wherein the data symbols have j bits per symbol and j<k, wherein the data signal is now represented by a stream of data symbols selected from the second signal space; encoding a voice signal to provide a stream of signal points subsequent to the detection of the off-hook signal; and adding the stream of signal points to the stream of data symbols selected from the second signal space to provide a stream of data plus voice signal points; wherein the step of transmitting now transmits the data plus voice signal points.
Claim 6
Independent Claim
159 words
A method for changing a data rate comprising the steps of: selecting a first signal space when no off-hook signal is detected; transmitting a data signal at a first data rate, where the data signal is represented by a stream of data symbols selected from the first signal space, the data symbols having k bits per symbol; selecting a second signal space when an off-hook signal is detected wherein the data symbols have j bits per symbol and j<k, wherein the data signal is now represented by a stream of data symbols selected from the second signal space; encoding a voice signal to provide a stream of signal points subsequent to the detection of the off-hook signal; and adding the stream of signal points to the stream of data symbols selected from the second signal space to provide a stream of data plus voice signal points; wherein the step of transmitting now transmits the data plus voice signal points.
Claim 7
Dependent Claim
79 words
Modem apparatus comprising: means for selecting a signal space as a function of the presence of an analog signal; means for selecting symbols from the selected signal space as a function of an applied data signal; means for adding to each one of the selected symbols a respective signal point that represents the analog signal if the analog signal is present to provide a sequence of resultant signal points; and means for transmitting the resultant sequence of signal points.
Claim 8
Dependent Claim
79 words
Modem apparatus comprising: means for selecting a signal space as a function of the presence of an analog signal; means for selecting symbols from the selected signal space as a function of an applied data signal; means for adding to each one of the selected symbols a respective signal point that represents the analog signal if the analog signal is present to provide a sequence of resultant signal points; and means for transmitting the resultant sequence of signal points.
Claim 9
Dependent Claim
13 words
The apparatus of claim 5 wherein the analog signal is a voice signal.
Claim 10
Dependent Claim
29 words
The apparatus of claim 6 wherein the means for selecting a signal space operates in response to detecting an off-hook signal, which represents the presence of the voice signal.
Claim 11
Dependent Claim
129 words
Apparatus for use in a simultaneous voice and data modem, the apparatus comprising: means for coupling the modem to a data signal source, an analog signal source and a communications channel; means responsive to the detection of an analog signal from the analog signal source for providing a resultant signal, wherein if no analog signal is detected, the resultant signal represents a sequence of data symbols selected from a first signal space, and if the analog signal is detected the resultant signal represents a sequence of signal points, where each signal point has a data symbol component and an analog signal component, where the data symbol component is selected from a second signal space; and means for transmitting the resultant signal to a far-end modem over the communications channel.
Claim 12
Dependent Claim
129 words
Apparatus for use in a simultaneous voice and data modem, the apparatus comprising: means for coupling the modem to a data signal source, an analog signal source and a communications channel; means responsive to the detection of an analog signal from the analog signal source for providing a resultant signal, wherein if no analog signal is detected, the resultant signal represents a sequence of data symbols selected from a first signal space, and if the analog signal is detected the resultant signal represents a sequence of signal points, where each signal point has a data symbol component and an analog signal component, where the data symbol component is selected from a second signal space; and means for transmitting the resultant signal to a far-end modem over the communications channel.
Claim 13
Dependent Claim
13 words
The apparatus of claim 8 wherein the analog signal is a voice signal.
Claim 14
Dependent Claim
33 words
The apparatus of claim 9 wherein the analog signal source is a telephone and further including a means of detecting the presence of the analog signal by the off-hook status of the telephone.
Claim 15
Dependent Claim
170 words
Data communication equipment apparatus: means responsive to an off-hook signal for selecting a first signal space when an off-hook signal is not present and for selecting a second signal space when the off-hook signal is present, where data symbols of the first signal space have k bits per symbol and data symbols of the second symbol space have j bits per symbol and j<k; means for encoding a voice signal after the off-hook signal is detected to provide a stream of voice signal points; means for encoding a data signal to provide a stream of data symbols from the selected signal space; means for adding the stream of signal points to the stream of data symbols after the off-hook signal is detected to provide a stream of data plus voice signal points; and means for transmitting the data signal as represented by either the stream of data symbols when the off-hook signal is not present or the stream of data plus voice signal points after the off-hook signal is detected.
Claim 16
Dependent Claim
170 words
Data communication equipment apparatus: means responsive to an off-hook signal for selecting a first signal space when an off-hook signal is not present and for selecting a second signal space when the off-hook signal is present, where data symbols of the first signal space have k bits per symbol and data symbols of the second symbol space have j bits per symbol and j<k; means for encoding a voice signal after the off-hook signal is detected to provide a stream of voice signal points; means for encoding a data signal to provide a stream of data symbols from the selected signal space; means for adding the stream of signal points to the stream of data symbols after the off-hook signal is detected to provide a stream of data plus voice signal points; and means for transmitting the data signal as represented by either the stream of data symbols when the off-hook signal is not present or the stream of data plus voice signal points after the off-hook signal is detected.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1998-12-11 | 1999-06-12 | 1999-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-11 | 2003-06-12 | 2003-12-12 | $3760.00 | Window Closed / Lapsed |
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