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US5237591A Expired / Lapsed US ⏱️ 0.0 years remaining

Circuit for digitally adding loss to a signal

Assignee: Nokia Bell Labs
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Filing: 1991-08-19
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Granted: 1993-08-17
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Expires: 2011-08-19
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Abstract

Abstract Disclosed is a circuit for adding loss to a signal in a loop carrier transmission system. As data is being transmitted, the circuit determines the digital output needed for an appropriate amount of loss for each channel unit at the end user interface.

Inventors

  • 👤 Kimerie W. Javitt
  • 👤 Kannan Ramchandran

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 13:32
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/02; H04L12/12; H04B; H04B14/00; H04B14/02; H04B14/04; H04B14/046; H04B14/048

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 101 words
A circuit comprising: means for receiving an input pulse code modulated digital word having a segment portion and step portion; circuit means for calculating a multiplicand based on the input word segment portion and step portion; circuit means for generating a desired loss coefficient; circuit means for serially multiplying the multiplicand by the desired loss coefficient; circuit means for calculating an addition factor based on the input word segment portion; circuit means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 2
Dependent Claim 101 words
A circuit comprising: means for receiving an input pulse code modulated digital word having a segment portion and step portion; circuit means for calculating a multiplicand based on the input word segment portion and step portion; circuit means for generating a desired loss coefficient; circuit means for serially multiplying the multiplicand by the desired loss coefficient; circuit means for calculating an addition factor based on the input word segment portion; circuit means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 3
Dependent Claim 16 words
The circuit according to claim 1 further comprising means for providing clock pulses to the circuit.
Claim 4
Dependent Claim 37 words
The circuit according to claim 2 wherein the means for providing clock pulses includes means for providing a faster clock pulse to the means for calculating the multiplicand than to the means for receiving the input word.
Claim 5
Dependent Claim 30 words
The circuit according to claim 1 wherein the multiplicand is given by: V.sub.old +16.5-(16.5·2.sup.-L.sbsp.old) where V old is the input step number and L old is the input segment number.
Claim 6
Dependent Claim 15 words
The circuit according to claim 4 wherein the addition factor is given by: 2.sup.-L.sbsp.old ·16.5.
Claim 7
Dependent Claim 19 words
The circuit according to claim 1 further comprising means for applying a loss coefficient to the serial multiplication means.
Claim 8
Dependent Claim 15 words
The circuit according to claim 6 wherein the loss coefficient is within the range 1/2-1.
Claim 9
Dependent Claim 30 words
The circuit according to claim 1 wherein the means for receiving the digital word comprises a serial-to-parallel converter and the means for transmitting the output word comprises a parallel-to-serial converter.
Claim 10
Dependent Claim 191 words
In a digital loop carrier transmission system, a remote terminal comprising a line interface unit for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the remote terminal and a central office, a trunk processing circuit for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the remote terminal and a plurality of channel units, and a circuit for adding loss to the digital stream coupled between the line interface unit and trunk processing circuit, said loss circuit comprising: means for receiving an input pulse code modulated word having a step portion and segment portion; means for calculating a multiplicand based on the input segment portion and step portion of the input word; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 11
Dependent Claim 191 words
In a digital loop carrier transmission system, a remote terminal comprising a line interface unit for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the remote terminal and a central office, a trunk processing circuit for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the remote terminal and a plurality of channel units, and a circuit for adding loss to the digital stream coupled between the line interface unit and trunk processing circuit, said loss circuit comprising: means for receiving an input pulse code modulated word having a step portion and segment portion; means for calculating a multiplicand based on the input segment portion and step portion of the input word; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 12
Dependent Claim 176 words
In a digital loop carrier transmission system, a distant terminal comprising a transceiver for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the distant terminal and a remote terminal, a trunk processing circuit for transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion to a channel unit, and a circuit for adding loss to the digital stream coupled between the transceiver and trunk processor, said loss circuit comprising: means for receiving an input pulse code modulated word having a segment portion and a step portion; means for calculating a multiplicand based on the input word segment portion and step portion; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 13
Dependent Claim 176 words
In a digital loop carrier transmission system, a distant terminal comprising a transceiver for receiving and transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion between the distant terminal and a remote terminal, a trunk processing circuit for transmitting a digital stream including pulse code modulated digital words each having a segment portion and step portion to a channel unit, and a circuit for adding loss to the digital stream coupled between the transceiver and trunk processor, said loss circuit comprising: means for receiving an input pulse code modulated word having a segment portion and a step portion; means for calculating a multiplicand based on the input word segment portion and step portion; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 14
Dependent Claim 172 words
In a digital loop carrier transmission system, a channel unit comprising a channel unit logic circuit for transmitting and receiving a digital stream including pulse code modulated digital words between the channel unit and another portion of the system, a line interface circuit for transmitting an analog signal between the channel unit and a customer, a Codec for converting between analog and digital signals, and a circuit for adding loss to the digital stream coupled between the channel unit logic circuit and the Codec, the loss circuit comprising: means for receiving an input pulse code modulated word having a segment portion and step portion; means for calculating a multiplicand based on the input word segment and step portion; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.
Claim 15
Dependent Claim 172 words
In a digital loop carrier transmission system, a channel unit comprising a channel unit logic circuit for transmitting and receiving a digital stream including pulse code modulated digital words between the channel unit and another portion of the system, a line interface circuit for transmitting an analog signal between the channel unit and a customer, a Codec for converting between analog and digital signals, and a circuit for adding loss to the digital stream coupled between the channel unit logic circuit and the Codec, the loss circuit comprising: means for receiving an input pulse code modulated word having a segment portion and step portion; means for calculating a multiplicand based on the input word segment and step portion; means for serially multiplying the multiplicand by a desired loss coefficient; means for calculating an addition factor based on the input word segment portion; means for adding the factor to the result of the serial multiplication in order to calculate an output pulse code modulated digital word; and means for transmitting the output word.

References Cited (Backward Citations)

US4595907A Cited
US4884285A Cited
US5008672A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-08-16 1997-02-15 1997-08-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-08-16 2001-02-15 2001-08-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-08-16 2005-02-15 2005-08-17 $7700.00 Window Closed / Lapsed

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