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US5684792A Expired / Lapsed US ⏱️ 0.0 years remaining

Echo canceller system in an ATM network

Assignee: Fujitsu Ltd
•
Filing: 1995-06-28
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Granted: 1997-11-04
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Expires: 2015-06-28
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Abstract

Abstract An echo canceller system for performing echo cancelling processing on a plurality of cells on a transmission line includes a plurality of echo canceller units to which the cells applied to the echo canceller system are allocated according to an applied order of the cells regardless of channels of the cells.

Inventors

  • 👤 Teruo Ishihara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 17:22
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5638; H04L2012/5646; H04L2012/5649

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 53 words
An echo canceller system for performing echo cancelling processing for a plurality of cells on a communication line, said system comprising: a plurality of echo canceller units to which said cells applied to the echo canceller system are allocated according to an applied order of the cells regardless of channels of the cells.
Claim 2
Dependent Claim 53 words
An echo canceller system for performing echo cancelling processing for a plurality of cells on a communication line, said system comprising: a plurality of echo canceller units to which said cells applied to the echo canceller system are allocated according to an applied order of the cells regardless of channels of the cells.
Claim 3
Dependent Claim 25 words
The echo canceller system as claimed in claim 1, wherein said applied order of the cells is an order of cellslot numbers of the cells.
Claim 4
Dependent Claim 33 words
The echo canceller system as claimed in claim 2, wherein each of said echo canceller units has a multiprocessing function of processing the cells during a process interval of cells including speech data.
Claim 5
Dependent Claim 72 words
The echo canceller system as claimed in claim 3, wherein said system further comprises common storage means, connected to said echo canceller units through a bus, for storing data necessary for the echo cancelling processes for each channel providing a cell to be processed, and each of the echo canceller units detects the channel from a header of the cell and accesses the data for the channel from the common storage means.
Claim 6
Dependent Claim 51 words
The echo canceller system as claimed in claim 4, wherein said common storage means comprises: a first common RAM storing tap data and tap coefficients for said each channel providing the cell to be processed; and a second common RAM storing data for updating the tap coefficients and controlling the data.
Claim 7
Dependent Claim 48 words
The echo canceller system as claimed in claim 5, wherein said echo canceller system further comprises: a common input data line receiving said plurality of cells which includes cells from a transmission line and cells from an echo pass; and a common output data line producing echo-cancelling-processed cells.
Claim 8
Dependent Claim 65 words
The echo canceller system as claimed in claim 5, wherein each of said echo canceller units comprises: an echo canceller circuit multiprocessing to generate a quasi-echo, calculate a remaining echo, and update the tap coefficients by accessing said first common RAM; and a digital signal processor multiprocessing to calculate update coefficients of the tap coefficients, detect a specified signal, and control said echo canceller circuit.
Claim 9
Dependent Claim 64 words
The echo canceller system as claimed in claim 7, wherein said echo canceller system further comprises: a common bus connecting a plurality of said echo canceller circuits and a plurality of said digital signal processors in the echo canceller units; and a controller allocating a usable time of said common bus to said digital signal processors according to an input timing of the cell.
Claim 10
Dependent Claim 112 words
The echo canceller system as claimed in claim 8, wherein said controller allocates the usable time of said common bus to said digital signal processors and produces a body number of the digital signal processor to which the usable time of the common bus is presently allocated to the other digital signal processors, said controller allcoating the usable time of said common bus to said digital signal processors in an order of body numbers of the digital signal processors, wherein each of the other digital signal processors recognizes a timing when the usable time of the common bus will be allocated to itself based on said body number produced by the controller.
Claim 11
Dependent Claim 29 words
The echo canceller system as claimed in claim 8, wherein said echo canceller system comprises a plurality of said common buses, and data is transmitted through the common buses.
Claim 12
Dependent Claim 57 words
The echo canceller system as claimed in claim 8, wherein said echo canceller system further comprises: a first print board onto which said plurality of the echo canceller circuits and said first common RAM are mounted; and a second print board onto which said plurality of the digital signal processors and said second common RAM are mounted.
Claim 13
Dependent Claim 62 words
The echo canceller system as claimed in claim 3, wherein a number of said echo canceller units is determined by a number of cellslots generated on the communication line during the process interval of the cells including the speech data, and the cells in the cellslots are permanently allocated to the echo canceller units according to the cellslot numbers of the cells.
Claim 14
Dependent Claim 64 words
The echo canceller system as claimed in claim 3, wherein a number m of said echo canceller units is determined by n times a number of cellslots generated in the communication line during the process interval of the cells including the speech data, and the cells in the cellslots are permanently allocated to the specified echo canceller units each n times the process interval.
Claim 15
Dependent Claim 52 words
The echo canceller system as claimed in claim 5, wherein said first common RAM and said second common RAM respectively include i banks, i being an integer larger than 1, the echo canceller units accessing all data stored in the first common RAM and the second common RAM by accessing each bank.
Claim 16
Dependent Claim 47 words
The echo canceller system as claimed in claim 14, wherein said first common RAM and said second common RAM respectively store said all data for all the channels, the data to be stored in each channel being divided into i parts which are stored in the banks.
Claim 17
Dependent Claim 135 words
The echo canceller system as claimed in claim 14, wherein: said echo canceller circuits are constructed with i groups of the circuits; said digital signal processors are constructed with i groups of the processors; said echo canceller system further comprises a first bus switch switching data buses between said i banks of the first common RAM and said i groups of the circuits, and a second bus switch switching data buses between said i banks of the second common RAM and said i groups of the processors; and each of said i groups of the circuits accesses all banks of the first common RAM by switching of the first bus switch, and each of said i groups of the processors accesses all banks of the second common RAM by switching of the second bus switch.
Claim 18
Dependent Claim 43 words
The echo canceller system as claimed in claim 2, wherein said cells are asynchronous transfer mode (ATM) cells transmitted in networks including ATM networks, and said order of cellslot numbers of the cells is an order of cellslot numbers of the ATM cells.
Claim 19
Dependent Claim 168 words
An echo canceller system for performing echo cancelling processing on a plurality of cells in a communication line, said system comprising: a common input data line receiving said plurality of cells which includes cells from a transmission line and cells from an echo pass; a common output data line producing echo-cancelling-processed cells; a plurality of echo canceller units, each of said units having a multiprocessing function of processing the cells received from said common input data line during a process interval of cells including speech data, each of said echo canceller units being independent of channels of the cells and being capable of processing any channels of the cells; and common storage means, connected to said echo canceller units through a bus, for storing data necessary for the echo cancelling processing for each channel providing a cell to be processed; wherein each of the echo canceller units detects a channel from a header of the cell and accesses the data for a channel from the common storage means.
Claim 20
Dependent Claim 168 words
An echo canceller system for performing echo cancelling processing on a plurality of cells in a communication line, said system comprising: a common input data line receiving said plurality of cells which includes cells from a transmission line and cells from an echo pass; a common output data line producing echo-cancelling-processed cells; a plurality of echo canceller units, each of said units having a multiprocessing function of processing the cells received from said common input data line during a process interval of cells including speech data, each of said echo canceller units being independent of channels of the cells and being capable of processing any channels of the cells; and common storage means, connected to said echo canceller units through a bus, for storing data necessary for the echo cancelling processing for each channel providing a cell to be processed; wherein each of the echo canceller units detects a channel from a header of the cell and accesses the data for a channel from the common storage means.
Claim 21
Dependent Claim 51 words
The echo canceller system as claimed in claim 18, wherein said common storage means comprises: a first common RAM storing tap data and tap coefficients for said each channel providing the cell to be processed; and a second common RAM storing data for updating the tap coefficients and controlling the data.
Claim 22
Dependent Claim 65 words
The echo canceller system as claimed in claim 19, wherein each of said echo canceller units comprises: an echo canceller circuit multiprocessing to generate a quasi-echo, calculate a remaining echo, and update the tap coefficients by accessing said first common RAM; and a digital signal processor multiprocessing to calculate update coefficients of the tap coefficients, detect a specified signal, and control said echo canceller circuit.
Claim 23
Dependent Claim 24 words
The echo canceller system as claimed in claim 18, wherein said cells are asynchronous transfer mode (ATM) cells transmitted in networks including ATM networks.
Claim 24
Dependent Claim 156 words
An echo canceller system for performing echo cancelling processing for a plurality of cells on a communication line, said system comprising: a plurality of echo canceller units to which said cells applied to the echo canceller system are allocated according to an applied order of the cells regardless of channels of the cells; and common storage means connected to said echo canceller units through a bus for each channel providing a cell to be processed and each echo canceller unit accesses data for the channel from said common storage means, wherein each of said echo canceller units comprises: an echo canceller circuit for multiprocessing to generate a quasi-echo, calculate a remaining echo, and update tap coefficients for each channel providing the cell to be processed by accessing said common storage means, and a digital signal processor for multiprocessing to calculate update coefficients of the tap coefficients, detect a specified signal, and control said echo canceller circuit.
Claim 25
Dependent Claim 156 words
An echo canceller system for performing echo cancelling processing for a plurality of cells on a communication line, said system comprising: a plurality of echo canceller units to which said cells applied to the echo canceller system are allocated according to an applied order of the cells regardless of channels of the cells; and common storage means connected to said echo canceller units through a bus for each channel providing a cell to be processed and each echo canceller unit accesses data for the channel from said common storage means, wherein each of said echo canceller units comprises: an echo canceller circuit for multiprocessing to generate a quasi-echo, calculate a remaining echo, and update tap coefficients for each channel providing the cell to be processed by accessing said common storage means, and a digital signal processor for multiprocessing to calculate update coefficients of the tap coefficients, detect a specified signal, and control said echo canceller circuit.

References Cited (Backward Citations)

US4803648A Cited
US4868874A Cited
JPH04349735A Cited
JPH05244248A Cited
US5457684A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-11-03 2001-05-05 2001-11-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-11-03 2005-05-05 2005-11-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-11-03 2009-05-05 2009-11-04 $7700.00 Window Closed / Lapsed

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