Method and system to increase the performance of high-speed backplanes

• US 6,601,007 B1
• Filed: 06/30/2000
• Issued: 07/29/2003
• Est. Priority Date: 06/30/2000
• Status: Expired due to Fees

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Higgins, Frank Patrick, Sweetman, Eric, Amir, Israel
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): Desta, Elias
• Application Number:
  US09/607,837
• Time in Patent Office: 1,124 Days
• Field of Search: 702/110, 702/118, 702/85, 702/122, 702/107, 702/126, 702/127, 702/189-191, 702/194, 702/195, 702/FOR-103, 702/134, 702/141, 710/1-7, 710/15, 710/18, 710/20, 710/21, 710/29, 710/31, 710/52, 710/55, 710/58, 710/60, 710/62, 710/65, 710/69, 710/70, 714/100, 714/724, 714/735, 714/824, 714/819, 714/799, 714/699, 370/230, 370/232, 370/234, 370/276, 370/277, 370/278, 370/282
• US Class Current: 702/107
• CPC Class Codes: H05K 1/0216 Reduction of cross-talk, noise or electromagnetic interference grounding H05K1/0215
• CPC Class Codes: H05K 1/14 Structural association of two or more printed circuits providing electric connection to or between printed circuits H05K1/11, H01R12/00
• CPC Class Codes: H05K 2201/044 Details of backplane or midplane for mounting orthogonal PCBs

Abstract

A circuit board, for use with a high speed backplane, includes transmitter and receiver with circuitry for correcting for multipath signal errors. A training sequence that is often a pseudo-random signal is transmitted by the transmitter on a first circuit board to a receiver located on a second circuit board. The receiver on the second circuit board includes an analog-to-digital signal converter, an equalizer, and a binary digital-to-analog reconverter for receiving the training sequence. The equalizer preferably comprises a series of connected registers having taps in between, a plurality of individual weighting means attached to each of the taps, and a summing means connected to the weighting means. A training sequence is transmitted from the first circuit board to the receiver on the second circuit board, enabling the receiver to adaptively determine a set of weighting means coefficients for correcting the multipath errors in subsequent signals. Coefficients for the weighting means are then adjusted from the output of the summing means. The method and system described can substantially reduce the cost of backplane fabrication and enhance the performance of the overall system.

Claims

1. A system for correcting the multipath distortion in a high-speed backplane with a plurality of sockets for receiving circuit boards comprising:

a. a first transmitter means located on a first circuit board plugged into a first of said sockets for transmitting a training sequence to a second board;

b. a first receiver means located on a second circuit board plugged into a second socket on said backplane for receiving said training sequence and for determining a correction value to correct for multipath distortion from subsequent signals, said first receiver means comprising;

(1) an analog-to-digital converter for receiving said training sequence;

(2) an equalizer means having an input connected to said analog-to-digital converter and an output; and

,

(3) a binary digital-to-analog converter having an input connected to the output of said equalizer means and an output connected to the rest of the circuit on said second circuit board;

c. a second receiver means located on said first circuit board; and

,

d. a second transmitter means located on said second circuit board,

wherein said second transmitter means transmits a training sequence through said backplane to said second receiver means which also receives said training sequence and determines a correction value to correct for multipath errors from subsequent signals; and

,

wherein said training sequence is a pseudo-random signal and said training sequence constitutes 1-10% of the total signal cycle time.