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Method and Apparatus for Delay Insensitive Transmission in Parallel Channels with Partial Synchronization

IP.com Disclosure Number: IPCOM000109958D
Original Publication Date: 1992-Oct-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 1 page(s) / 51K

Publishing Venue

IBM

Related People

Blaum, M: AUTHOR [+2]

Abstract

Assume that information is transmitted in parallel among many lines in such a way that an electrical transition represents a 1 and an absence of a transition represents a 0. The propagation delay in the wires varies and results in asynchronous reception. The challenge is to find an efficient communication scheme that will be delay-insensitive. One of the common solutions to this problem is to use a handshake mechanism. Namely, the transmitter sends the next vector only after getting an acknowledgement that the current vector was received. A natural question is: how does the receiver know that reception of the current vector is complete? This problem was solved by [1], by using the so-called unordered codes.

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Method and Apparatus for Delay Insensitive Transmission in Parallel Channels with Partial Synchronization

       Assume that information is transmitted in parallel among
many lines in such a way that an electrical transition represents a 1
and an absence of a transition represents a 0.  The propagation delay
in the wires varies and results in asynchronous reception.  The
challenge is to find an efficient communication scheme that will be
delay-insensitive.  One of the common solutions to this problem is to
use a handshake mechanism.  Namely, the transmitter sends the next
vector only after getting an acknowledgement that the current vector
was received.  A natural question is: how does the receiver know that
reception of the current vector is complete?  This problem was solved
by [1], by using the so-called unordered codes.  However, in
practice, it is common that the communication lines are arranged in
pairs (double-rail) such that the propagation delay on the lines
within a pair is identical.  In general, the lines can be grouped
into groups (of size larger than 1) where transmission within a group
is sychronized.  New schemes have been created that take advantage of
partial synchronization within the groups and result in a more
efficient scheme than the scheme of [1].  To acheive generalizing of
the alphabet, the following are known results:
      1.   Knuth's construction of balanced codes [2]; and
      2.   Berger's construction of unorder...