Thesis - Open Access
Master of Science (MS)
The compression of information into smaller and smaller bandwidths has been a constant struggle against an expanding demand. Since the modulation of a carrier necessarily produces sidebands, signals cannot be sent in zero bandwidth. For some time, attempts were made to beat nature, until the natural limits of noise and bandwidth were established. Men like Hartley, Nyquist, and Shannon set a sound scientific base and as a result, rules and limits have been Developed. But this struggle continues with ever more sophisticated demands. As requirements for larger amounts of scientific data arise, methods for utilizing the available means of data transmission efficiently are needed. For many years, communication engineers have discussed the advantages of a simple and reliable means of transmitting, recording, and processing all of the data. Although these engineers contemplated such means, they concentrated on designing for wider bandwidths and more power--the brute-force way to transfer an ever-increasing mass of data in a given period of time. Eventually, realizing that this effort was futile, communication engineers used the knowledge gained from their past efforts and applied it t6 design a way for transmitting only the significant data or information. The methods devised are called data compression methods. Data compression is a technique to reduce the bandwidth needed to transmit a given amount of information in a given time or to reduce the time needed to transmit a given bandwidth signal. Such compress ion must eliminate redundancies so that only those values which are essential to the faithful reproduction of the input signal (relative to some error criterion) are transmitted. The performance enhancement of a basic data acquisition system by incorporation of data compression can be manifested in a variety of ways, depending. In part, on the manner in which the data compressor is utilized in the system and the performance desired. As indicated in Figure 1, the engineer has the option of incorporating data compression into either the transmitter or the receiver portions of the system. Four basic categories of data handling come under this definition: parameter extraction, adaptive sampling, redundancy reduction, and encoding.
Library of Congress Subject Headings
Data compression (Telecommunication)
Number of Pages
South Dakota State University
Birznieks, Uldis, "Computer Simulation of a New Redundancy Reduction Technique" (1969). Electronic Theses and Dissertations. 3527.