Download or read book PERFORMANCE ANALYSIS OF CODED FREQUENCY HOPPED SPREAD SPECTRUM SYSTEMS WITH UNKNOWN INTERFERENCE written by MANJUNATH V. HEGDE and published by . This book was released on 1987 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: combining and linear combining, are unable to overcome the worst case partial band noise, but clipped linear combining is asymptotically able to neutralize the partial band noise, i.e. allow its effect to be no worse than added white Gaussian noise of equivalent noise spectral density.

Download or read book Performance Analysis of Coded Frequency Hopped Spread Spectrum Systems with Unknown Interference written by M. V. Hedge and published by . This book was released on 1987 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two classes of problems are considered. In the first class we model the process of communicating in the presence of interference, which is unknown or hostile, as a two-person zero sum game with the communicator and the jammer as the players. The objective functions we consider are mutual information and the channel cutoff rate. The communicator's strategies are distributions on the input alphabet and on a set of quantizers and the jammer's strategies are distributions on the noise power subject to certain constraints. We consider various conditions on the jammer's strategy set and on the communicator's knowledge. For the case with the decoder uninformed of the actual quantizer chosen, we show that, from the communicator's perspective the worst-case jamming strategy is a distribution concentrated at a finite number of points thereby converging a functional optimisation problem into a nonlinear programming problem. Moreover, we are able to also characterize the worst-case distributions by means of necessary and sufficient conditions which are easy to verify. For the case with the decoder informed of the actual quantizer chosen we are able to demonstrate the existence of saddle-point strategies.

Download or read book PERFORMANCE ANALYSIS OF FREQUENCY HOPPED SPREAD SPECTRUM COMMUNICATION SYSTEMS WITH WORST CASE JAMMING INTERFERENCE written by SANG KYU PARK and published by . This book was released on 1987 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: strategies we consider allow the jammer to pulse between several power values subject to an average power constraint.

Download or read book Performance analysis of frequency hopped spread spectrum communication withworst case jamming interference written by Sang K. Park and published by . This book was released on 1987 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis for a New Model of the Fast Frequency Hopped Code Division Multiple Access Spread Spectrum Communication System written by Ming-li Shen and published by . This book was released on 1993 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Coding for Frequency hopped Spread spectrum Channels with Partial band Interference written by Wayne Eric Stark and published by . This book was released on 1982 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of codes on frequency-hopped spread-spectrum channels with partial-band interference is investigated. The asymptotic performance of codes is measured by the channel capacity and the random coding exponent. The performance of specific codes is measured by the bit error probability. The channel models we consider are quite general and include channels with unknown parameters, channels which change with time, and channels with memory. These models are applicable to frequency-hopped spread-spectrum communication systems as well as to several other communication systems. We formulate the problem of communicating over channels with unknown transition probabilities (i.e. communicating over channels with jamming) as a game theory problem with payoff function being the mutual information between the channel input and the channel output. Under certain restrictions it is shown that memoryless coding and jamming strategies are simultaneously optimal strategies. Next we develop simple, yet accurate, models for many channels with memory that arise in practice. The channel statistics are constant for blocks of symbols of fixed length. The receiver is said to have side information if it can determine the channel statistics for each block of symbols transmitted.

Download or read book Spread Spectrum Systems written by Robert Clyde Dixon and published by Wiley-Interscience. This book was released on 1984 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis of a Coherent Frequency Hopped Spread Spectrum Receiver in the Presence of Jamming Phase Uncertainty and Non ideal Channel Response written by Chun-Meng Su and published by . This book was released on 1989 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Study of Hybrid Spread Spectrum Techniques written by and published by . This book was released on 2005 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on the performance analysis of hybrid direct sequence/slow frequency hopping (DS/SFH) and hybrid direct sequence/fast frequency hopping (DS/FFH) systems under multi-user interference and Rayleigh fading. First, we analyze the performance of direct sequence spread spectrum (DSSS), slow frequency hopping (SFH) and fast frequency hopping (FFH) systems for varying processing gains under interference environment assuming equal bandwidth constraint with Binary Phase Shift Keying (BPSK) modulation and synchronous system. After thorough literature survey, we show that hybrid DS/FFH systems outperform both SFH and hybrid DS/SFH systems under Rayleigh fading and multi-user interference. Also, both hybrid DS/SFH and hybrid DS/FFH show performance improvement with increasing spreading factor and decreasing number of hopping frequencies.

Download or read book Performance Analysis of Diversity Combining for Frequency hop Communications Under Partial band and Multitone Interference written by Gang Li and published by . This book was released on 1992 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance of Cellular Frequency Hopped Spread Spectrum Radio Networks written by Jeffrey W. Gluck and published by . This book was released on 1989 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiple access interference is characterized for cellular mobile networks, in which users are assumed to be Poisson-distributed in the plane and employ frequency-hopped spread-spectrum signaling with transmitter-oriented assignment of frequency-hopping patterns. Exact expressions for the bit error probabilities are derived for binary coherently demodulated systems without coding. Approximations for the packet error probability are derived for coherent and noncoherent systems and these approximations are applied when forward-error-control coding is employed. In all cases, the effects of varying interference power are accurately taken into account according to some propagation law. Numerical results are given in terms of bit error probability for the exact case and throughput for the approximate analyses. Comparisons are made with previously derived bounds and it is shown that these tend to be very pessimistic. Keywords: Communications network; Multiple access; Frequency hopping; Spread spectrum; Error control coding. (jhd).

Download or read book Performance Analysis of Frequency Hopped Spread Spectrum Multiple Access FH SSMA Communication Systems written by Khalid Ali Qaraq'e and published by . This book was released on 1997 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Reports Awareness Circular TRAC written by and published by . This book was released on 1988 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis of Noncoherent Slow Frequency hopped Spread spectrum Communications Over Specular Multipath Fading Channels written by Kuo Tung Chiang and published by . This book was released on 1986 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis for Fast Frequency Hopped Spread Spectrum Multiple Access Communications written by E. A. Geraniotis and published by . This book was released on 1981 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Diversity Combining for Frequency hop Spread spectrum Communications with Partial band Interference and Fading written by Catherine Marie Keller and published by . This book was released on 1985 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents results on the evaluation of several diversity combining techniques that are suggested for frequency-hop (FH) communications with partial-band interference and fading. The analysis covers systems with M-ary orthogonal signaling and noncoherent demodulation. The partial-band interference is modeled as a Gaussian process, although some of the results also apply to general (non-Gaussian) partial-band interference. The performance measures we use to evaluate the diversity combining techniques are the narrowband interference rejection capability and the signal to noise ratio requirement over the entire range of interference duty factors. We evaluate the exact probability of error for each of the diversity combining techniques studied. The performance of the optimum combining technique for receivers with perfect side information is established. It is shown that for receivers with perfect side information, the system performance does not change significantly with the choice of the diversity combining technique. However, the same schemes that work well in receivers with perfect side information perform poorly in receivers without side information. Keywords include: Diversity combining; Frequency-hop; Spread-spectrum; Partial band interference and Fading.