Browse Prior Art Database

INTELLIGENT DELAY vs. TRUNCATION

IP.com Disclosure Number: IPCOM000008224D
Original Publication Date: 1997-Jun-01
Included in the Prior Art Database: 2002-May-29
Document File: 2 page(s) / 79K

Publishing Venue

Motorola

Related People

David Helm: AUTHOR [+3]

Abstract

The Comparator is an infrastructure device responsible for analog/digital voice/data voting for a 2-way radio communications system. The Comparator receives multiple signals and must arbitrate which signal is transmitted. This involves handling the transition between the end of one signal and the beginning of a new signal. The term source change is used to describe this transition. As a result of source changes, delay or truncation of the new signal may occur.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 56% of the total text.

Page 1 of 2

M-LA Technical Developments

INTELLIGENT DELAY vs. TRUNCATION

by David Helm, Phillip Hargrave and Jeffrey Thurston

BACKGROUND

  The Comparator is an infrastructure device responsible for analog/digital voice/data voting for a 2-way radio communications system. The Comparator receives multiple signals and must

arbitrate which signal is transmitted. This involves handling the transition between the end of one signal and the beginning of a new signal. The term source change is used to describe this transition. As a result of source changes, delay or truncation of the new signal may occur.

PROBLEM

  The previous Comparators followed rigid rules to decide when a signal would be truncated and when a signal would be delayed. One problem this caused was when performing multiple source changes, the buffers within the Comparator could be exceeded due to delaying the new signal. Also source changes could cause late entry due to truncation of the preamble frame of the new signal. If the new signal was a data signal the entire data message would be thrown away. Truncation of a voice signal causing late entry is depicted in the following diagram.

Data PDU

High Prioirty In

LOW Priority In

PRE LDUl I LDU2

I I

I ,

I

LDUZ

I I ,

I I

Data PDU

Out I

  These problems are not restricted to the Comparator. Any multiple source priority/preemp- tion device must address these problems.

SOLUTION

  The decision of whether to truncate or delay will be made intelligently. The type of signal and the eff...