This thesis investigates the anti-jam performance of an adaptive spread spectrum communication's system. The adaptive filter is assumed to be ideal in that it perfectly locates the jamming signal and adapts its bandwidth to exactly filter out the jamming signal. The colored-noise (jammer) and bandlimited white noise are considered to have flat power spectral densities within their respective bandwidths. The spread spectrum technique considered is that of direct sequence modulation. Three criteria are used to evaluate the system: autocorrelation peak degradation, signal-to-noise ratio, and intersymbol interference. The results indicate that an adaptive spread spectrum communication's system is able to provide an increased jam resistant communication system. (Author).

This edition features a wealth of new material on urban warfare, including a computer simulation of EW architecture alternatives for land-based forces based on urban constraints. It also includes an expanded section on time-hopped spread spectrum communications, more details on modern communication system technologies such as CDMA and OFDM, and an in-depth discussion on sources of urban noise. This practical resource is focused on showing the reader how to design and build jammers specifically targeted at spread spectrum, anti-jam communications. Moreover, it gives assistance in evaluating the expected performance of jamming systems against modern communications systems, and discover the best waveform to use to counter communication systems designed to be effective in jamming environments. While mathematical derivations in general are avoided, the book presents error rate performance equations for most modern digital anti-jam communication systems

In anti-jam communication systems which employ error correction coding, the assumption is often made that the coding channel is memoryless. This assumption is typically justified by claiming that ideal or adequate interleaving is used. The thesis addresses two relevant issues: what is adequate interleaving, and how much is performance compromised when interleaving is less than adequate? A definition of adequate interleaving was determined from existing literature. Using this definition, it was possible to simulate overloaded interleavers. These convolutional interleavers operating under less than ideal conditions were analyzed, and a procedure was developed for determining the system error probability under these conditions. One important observation concerning convolutional interleavers is that while they do break up the burst interference of a pulse jammer, the scrambling is always done in a deterministic manner, and thus the channel with memory is not converted to a truly memoryless channel as is often assumed.

CONTENS 1. B. Bo2id, N. Vidojevid, N. Novovid-Simovid, R. Keredki — The influence of austenitization conditions on the correlation between the microstructure and mechanical properties of low-alloyed CrNiMo Steel 1 2. B. Bo2i6, Z. Cvijovie, D. Mihajlovid — An Analysis of the shape of intermetallic phases 9 3. M. M. Ristid, P. Kostio, Jong-I-lee Park — The possibility of obtaining YBa2Cu30), with required properties 17 4. L. J. Challis, A. J. Kent, V. W. Rampton — Listening to Electrons — 23 5. B. Bo06, Z. Cvijovid, D. Mihajlovid — Stereometric parameters of eutectic Microconsti:tuent in Al-Zn-Mg-Cu Alloys 37 6. I. S. Stojanovid, Zorka D. Stojanovie, M. L. Dukid — Analysis of new methods proposed for the narrow-band interference Isuppresion in telecommunication systems using spread spectrum technique — — — 45 Ово дело је лиценцирано под условима лиценце Creative Commons - Attribution-Noncommercial-No Derivative Works 3.0 Serbia http://creativecommons.org/licenses/by-nc-nd/3.0/rs/deed.en

This textbook provides a concise but lucid explanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles. The choice of specific topics is tempered by the author’s judgment of their practical significance and interest to both researchers and system designers. Throughout the book, learning is facilitated by many new or streamlined derivations of the classical theory. Problems at the end of each chapter are intended to assist readers in consolidating their knowledge and to provide practice in analytical techniques. This third edition includes new coverage of topics such as CDMA networks, Acquisition and Synchronization in DS-CDMA Cellular Networks, Hopsets for FH-CDMA Ad Hoc Networks, and Implications of Information Theory, as well as updated and revised material on Central Limit Theorem, Power Spectral Density of FH/CPM Complex Envelopes, and Anticipative Adaptive-Array Algorithm for Frequency-Hopping Systems.