Title:
アナログ信号を送信機から電話回線を通して受信する受信機に使用される装置
Document Type and Number:
Japanese Patent JP3549606
Kind Code:
B2
Abstract:
Analog signals representing individual digital values (+3,+1, -1,-3) of data pass through a telephone line to a receiver (22). These signals may first be provided in a pseudo random sequence. A linear echo canceller (34) and a first adder (32) at the receiver simultaneously eliminate, to some extent, echo signals resulting from second analog signals transmitted through the telephone line by the receiver. A non-linear echo canceller (42) and a second adder (40) further significantly reduce the echo signals and specifically reduce non-linear components in the echo signals. Adjustable signal delays achieve optimal performance of the linear and non-linear echo cancellers. In one inventive embodiment, each echo canceller includes a memory which stores, for each terminal in such echo canceller, data representing (a) the pseudo random sequence and (b) coefficients for adjusting the signals in such sequence. Such data for each terminal in such echo canceller is recorded in the memory for introduction to the next terminal in the memory. For each terminal in such echo canceller, the signals representing the data for the coefficient and the output from the associated adder are processed to determine an adjusted value of such coefficient for storage in the memory and for use in the next cycle of processing. The adjusted coefficient value and the data stored in the memory for such terminal are processed to produce signals for introduction to the associated adder. The signals from the second adder are processed to restore the data transmitted through the telephone line to the receiver.
Inventors:
Daniel Esig
Application Number:
JP6330095A
Publication Date:
August 04, 2004
Filing Date:
February 14, 1995
Export Citation:
Assignee:
Brooktree Corporation
International Classes:
H04B3/23; H04M11/00; H03H21/00; (IPC1-7): H04B3/23; H04M11/00
Domestic Patent References:
| JP62256535A | ||||
| JP6342528A | ||||
| JP8172383A |
Other References:
Daniel Essig, Tim Lindenfelser, Ehud Rokach, Wendy Liu, Perry Lou, Doug Moran and Brad Seago,“An HDSL chipset For High-Speed Transmission Over Copper”,Proceedings of ICC/SUPERCOMM'94 - 1994 International Conference on Communications,1994年 5月 5日,Vol.1,pp.461-465
Attorney, Agent or Firm:
Hideto Asamura
Hajime Asamura
Hayashi Zouzo
Kuniaki Shimizu
Hajime Asamura
Hayashi Zouzo
Kuniaki Shimizu