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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Transform domian/cyclic code shift keying system on an urban multipath channel

Alsharekh, Mohammed Fahad. January 1998 (has links)
Thesis (M.S.)--Ohio University, August, 1998. / Title from PDF t.p.
92

An implementation of TD/CCSK waveform using optical signal processing

Chindapol, Aik. January 1996 (has links)
Thesis (M.S.)--Ohio University, November, 1996. / Title from PDF t.p.
93

Using TD/CCSK spread spectrum technique to combat multipath interference in a multiple user system

Chen, Chi-She. January 1995 (has links)
Thesis (M.S.)--Ohio University, November, 1995. / Title from PDF t.p.
94

Evaluation of pseudorandom sequences used in third generation spread spectrum systems /

Manchiraju, Dinakar. January 2003 (has links)
Thesis (M.S.)--Ohio University, November, 2003. / Includes bibliographical references (p. 59).
95

A multiple access interference rejection technique using weighted despreading functions for direct-sequence code division multiple access communications /

Huang, Yuejin. January 1998 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1998. / Includes bibliographical references.
96

Propagation measurement based estimation and comparison of DSSS microcellular mobile link performance at 2.25 and 5.8 GHz /

Han, Min, January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 108-110). Also available in electronic format on the Internet.
97

Multiuser multirate DS-CDMA detection techniques in multipath fading channels /

Yang, Bin. January 1900 (has links)
Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 213-224). Also available in electronic format on the Internet.
98

Evaluation of pseudorandom sequences used in third generation spread spectrum systems

Manchiraju, Dinakar. January 2003 (has links)
Thesis (M.S.)--Ohio University, November, 2003. / Title from PDF t.p. Includes bibliographical references (p. 59)
99

Throughput analysis for code division multiple accessing of the spread spectrum channel

January 1984 (has links)
Joseph Y.N. Hui. / Bibliography: p. [5] / "September 1984." Reprinted from IEEE Journal on Selected Areas in Communications, vol. SAC-2, no.4, July 1984. / "... supported by the National Science Foundation under Grant NSF/ECS 78-19880..." "... Advanced Project Agency under Grant ONR-N00014-75-C1183."
100

Performance analysis of suboptimal soft decision DS/BPSK receivers in pulsed noise and CW jamming utilizing jammer state information

Juntti, J. (Juhani) 17 June 2004 (has links)
Abstract The problem of receiving direct sequence (DS) spread spectrum, binary phase shift keyed (BPSK) information in pulsed noise and continuous wave (CW) jamming is studied in additive white noise. An automatic gain control is not modelled. The general system theory of receiver analysis is first presented and previous literature is reviewed. The study treats the problem of decision making after matched filter or integrate and dump demodulation. The decision methods have a great effect on system performance with pulsed jamming. The following receivers are compared: hard, soft, quantized soft, signal level based erasure, and chip combiner receivers. The analysis is done using a channel parameter D, and bit error upper bound. Simulations were done in original papers using a convolutionally coded DS/BPSK system. The simulations confirm that analytical results are valid. Final conclusions are based on analytical results. The analysis is done using a Chernoff upper bound and a union bound. The analysis is presented with pulsed noise and CW jamming. The same kinds of methods can also be used to analyse other jamming signals. The receivers are compared under pulsed noise and CW jamming along with white gaussian noise. The results show that noise jamming is more harmful than CW jamming and that a jammer should use a high pulse duty factor. If the jammer cannot optimise a pulse duty factor, a good robust choice is to use continuous time jamming. The best performance was achieved by the use of the chip combiner receiver. Just slightly worse was the quantized soft and signal level based erasure receivers. The hard decision receiver was clearly worse. The soft decision receiver without jammer state information was shown to be the most vulnerable to pulsed jamming. The chip combiner receiver is 3 dB worse than an optimum receiver (the soft decision receiver with perfect channel state information). If a simple implementation is required, the hard decision receiver should be used. If moderate complex implementation is allowed, the quantized soft decision receiver should be used. The signal level based erasure receiver does not give any remarkable improvement, so that it is not worth using, because it is more complex to implement. If receiver complexity is not limiting factor, the chip combiner receiver should be used. Uncoded DS/BPSK systems are vulnerable to jamming and a channel coding is an essential part of antijam communication system. Detecting the jamming and erasing jammed symbols in a channel decoder can remove the effect of pulsed jamming. The realization of erasure receivers is rather easy using current integrated circuit technology.

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