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Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1992. / Vita. Abstract. Includes bibliographical references (leaves 66-68). Also available via the Internet.

First generation digital codecs for speech have been the subject of worldwide studies since the sixties. Speech quality very close to that of the standard 64 Kbit/s PGM, the ability to carry voice band data all at reasonable complexity and cost are the main objectives of candidate coding techniques. This work deals with the subjective performance evaluation of two types of reduced bit-rate encoding techniques operating at 32 Kbit/s, for inclusion into business satellite communication systems. They are CVSDM and ADPCM, which are both capable of doubling the existing transponder capacity available in business satellite systems. The aim has been to determine transmission planning figures for their quality in terms of Richards' Q-factor. The work is also involved with the implementation of different ADPCM algorithms using digital signal processor (DSP) single chips which is fairly new to the field of telecommunications. Throughout the work the replacement of 64 Kbit/s PCM coder by 32 Kbit/s coder in satellite communication systems has been the theme. The achievement of acceptable subjective quality being the major objective.

Space vehicle is a kind of tool and weapon for transporting materials and personnel, conveying energy and execution work in space. The war of 21st century is a Hi-Tech war to fight for the power over space control and information transmission. Space power means the control of information transmission, and therefore the victory of this war and quality of space vehicle is the key factor in determining Whether one has the power space in. China was developed space vehicle technology since 1956 After great efforts for half a century, it has already established certain foundation. China like U.S.A and Russia, has invested huge funds and manpower in developing space science and technology. China hopes to improve military strength, drive the development of relevant industries and economy, and increase national competitiveness and overall strength through the development in space vehicle science and technology, and further conquer this expects to new high land of space. This paper aims at studying the development, capabilities, restrictions, and breakthroughs the space vehicle technology of China in terms of China¡¦s position on the control over space and its strategic intention in developing space vehicles. This paper reveals the direction of space vehicle development in China and suggests measures for maintaining Taiwan security. It will help to provide a relevant background for the future study of space vehicle development in China.

Thesis (M.S.)--University of Illinois at Urbana-Champaign, 1972. / Includes bibliographical references (leaves 301-306).

Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1991. / Vita. Abstract. Includes bibliographical references (leaves 117-125). Also available via the Internet.