Browse Prior Art Database

NUMERIC REDUNDANCY FOR ALPHANUMERIC INFORMATION TRANSMISSION

IP.com Disclosure Number: IPCOM000006250D
Original Publication Date: 1991-Dec-01
Included in the Prior Art Database: 2001-Dec-18
Document File: 2 page(s) / 93K

Publishing Venue

Motorola

Related People

Morris Moore: AUTHOR

Abstract

For wide are a alphanumeric paging and other similar services, there is a high price associated with achieving "near error free" transmission. At the fringe of cover- age, some errors are inevitable. Errors in the numeric portions of alphanumeric information are more unde- sirable than errors in the alpha portion since context is not generally very helpful for numeric information that may be associated with times, dates, currency amounts, etc. However, today, all information is coded in the same manner. An alternative is to provide additional coding only on the numeric portions, in effect compensating their lack of contextual redundancy without adding over- head to the more redundant alpha portions. In digitized compressed voice (vocoders), corruption of certain speech parameters produces signiticantly more detrimen- tal effect on the reconstructed speech than other param- eters. It is common to apply different levels of coding for transmission to different parameters on this basis.

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MOTOROLA INC. Technical Developments Volume 14 December 1991

NUMERIC REDUNDANCY FOR ALPHANUMERIC INFORMATION TRANSMISSION

by Morris Moore

  For wide are a alphanumeric paging and other similar services, there is a high price associated with achieving "near error free" transmission. At the fringe of cover- age, some errors are inevitable. Errors in the numeric portions of alphanumeric information are more unde- sirable than errors in the alpha portion since context is not generally very helpful for numeric information that may be associated with times, dates, currency amounts, etc. However, today, all information is coded in the same manner. An alternative is to provide additional coding only on the numeric portions, in effect compensating their lack of contextual redundancy without adding over- head to the more redundant alpha portions. In digitized compressed voice (vocoders), corruption of certain speech parameters produces signiticantly more detrimen- tal effect on the reconstructed speech than other param- eters. It is common to apply different levels of coding for transmission to different parameters on this basis.

  Figure 1 is a block diagram showing the basic blocks in an alphanumeric paging system which applies this alternative method for handling alphanumeric information. Note that only the blocks lab&cd NUMERIC CODING and NUMERIC DECODING arc new. These blocks add and remove the additional coding redundancy respectively,

adding increased protection to the numeric information.

  As shown in Figure 2, the encoder would identify the character values associated with numeric information (codes 48-57) and apply an encoding scheme with addi- tional redundancy instead of the standard alpha coding method. At the receiver, the numeric information would be identified and the corresponding numeric decoding would replace the standard alpha decoding.

  For example, one simple scheme would...