CA2026663A1 - Idle channel noise reduction in a line card having a dsp equalizer - Google Patents

Idle channel noise reduction in a line card having a dsp equalizer

Info

Publication number
CA2026663A1
CA2026663A1 CA 2026663 CA2026663A CA2026663A1 CA 2026663 A1 CA2026663 A1 CA 2026663A1 CA 2026663 CA2026663 CA 2026663 CA 2026663 A CA2026663 A CA 2026663A CA 2026663 A1 CA2026663 A1 CA 2026663A1
Authority
CA
Canada
Prior art keywords
noise reduction
line card
idle channel
channel noise
increases
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA 2026663
Other languages
French (fr)
Other versions
CA2026663C (en
Inventor
Anthony Michael Andruzzi, Jr.
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nortel Networks Ltd
Original Assignee
Northern Telecom Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Northern Telecom Ltd filed Critical Northern Telecom Ltd
Priority to CA 2026663 priority Critical patent/CA2026663C/en
Publication of CA2026663A1 publication Critical patent/CA2026663A1/en
Application granted granted Critical
Publication of CA2026663C publication Critical patent/CA2026663C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Dc Digital Transmission (AREA)
  • Control Of Amplification And Gain Control (AREA)

Abstract

IDLE CHANNEL NOISE REDUCTION IN A LINE CARD
HAVING A DSP EQUALIZER

Abstract of the Disclosure Idle channel noise reduction is achieved in a line card having an analog gain/attenuator, a codec, and a digital signal processor including an equalizer and a digital gain/attenuator. A peak detector samples output from the codec each 8 kHz cycle. A level decision compares the sample to a stored peak value, and replaces the stored peak value with the sample if it is greater. A controller, at a second predetermined interval, increases analog gain in steps and increases digital attenuation in similar steps if the stored peak value is greater than the predetermined threshold. Otherwise, the controller increases analog attenuation in steps and increases digital gain in similar steps.

- i -
CA 2026663 1990-09-19 1990-09-19 Idle channel noise reduction in a line card having a dsp equalizer Expired - Fee Related CA2026663C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA 2026663 CA2026663C (en) 1990-09-19 1990-09-19 Idle channel noise reduction in a line card having a dsp equalizer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA 2026663 CA2026663C (en) 1990-09-19 1990-09-19 Idle channel noise reduction in a line card having a dsp equalizer

Publications (2)

Publication Number Publication Date
CA2026663A1 true CA2026663A1 (en) 1992-03-20
CA2026663C CA2026663C (en) 1999-08-03

Family

ID=4146079

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 2026663 Expired - Fee Related CA2026663C (en) 1990-09-19 1990-09-19 Idle channel noise reduction in a line card having a dsp equalizer

Country Status (1)

Country Link
CA (1) CA2026663C (en)

Also Published As

Publication number Publication date
CA2026663C (en) 1999-08-03

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