Abstract/Details

DATA COMPRESSION OF BAUDED SIGNALS USING THE BASEBAND RESIDUAL VECTOR QUANTIZATION ALGORITHM

TRAN, THAO DUY. 
 The University of Utah ProQuest Dissertations Publishing,  1987. 8727361.

Abstract (summary)

This dissertation concerns the design of a data compression algorithm for a class of voiceband data signals. In this dissertation, a vector quantization algorithm, which is called the Baseband Residual Vector Quantization (BRVQ) algorithm, for single channel, low to medium rate modem signals is presented. The class of signals being studied includes various phase-shift-keyed and frequency-shift-keyed signals of data rates at or below 4800 bits/s.

In the BRVQ algorithm, the input passband signal is converted to its baseband equivalent whose magnitude and phase are vector quantized separately. Due to the structure embedded in the baseband signal, the phase within each baud of the baseband signal is modeled by a straight line and the residual (the modelling error) is vector quantized. The reason that quantization is done on the residual instead of on the phase is twofold. First, the residual sequence in general has a smaller dynamic range than that of the phase sequence. As a result, a vector quantizer using a fixed number of bits will perform better with the residual than with the phase. Second, one codebook is adequate for different types of modulation since the residual does not have as much structure in it as the phase. As a by-product of the research, a new carrier frequency estimation scheme and an accurate baud rate classification scheme have been developed.

Experimental results show that the BRVQ system is successful in compressing a relatively broad class of voiceband data signals at approximately 16 kbits/s. Moreover, the results obtained also show that the system has a potential for compressing most of the signals in the test signal set at rates below 16 kbits/s. The complexity of the BRVQ algorithm is three times less than that of an existing data compression algorithm at a comparable performance. The substantial advantage of the BRVQ system is the use of only one codebook for the residual for different types of signals. Another advantage of the BRVQ system is its insensitivity to errors in the carrier frequency estimation due to the straight line model for the phase.

Indexing (details)


Subject
Electrical engineering
Classification
0544: Electrical engineering
Identifier / keyword
Applied sciences
Title
DATA COMPRESSION OF BAUDED SIGNALS USING THE BASEBAND RESIDUAL VECTOR QUANTIZATION ALGORITHM
Author
TRAN, THAO DUY
Number of pages
167
Degree date
1987
School code
0240
Source
DAI-B 48/09, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
979-8-206-58541-4
University/institution
The University of Utah
University location
United States -- Utah
Degree
Ph.D.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
8727361
ProQuest document ID
303609161
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
https://www.proquest.com/docview/303609161