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 Performance Study of Modified Frequency Hopping Spread Spectrum Multiple Access Packet Communication Systems written by Ki Jong Hong and published by . This book was released on 1982 with total page 288 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 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 Performance Analyses of Frequency hopped Spread spectrum Multiple Access Systems in Fading Environments written by Usa Svasti-Xuto and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this dissertation is the performance analyses of two classes of frequency-hopped spread-spectrum multiple access (FH-SSMA) systems in various fading environments. The capacity of Viterbi's FH-SSMA system is evaluated under three types of fading, namely Rician, shadowed Rician, and Nakagami fading. The results of recent experiments have indicated that these fading phenomena occur in various environments where the FH-SSMA system may be implemented. In this dissertation, the deletion probability for each fading scenario is derived. Subsequently, the system capacity is analyzed in terms of maximum number of users versus average bit error rate. The effect of a change in the signal-to-noise ratio level on the system capacity is also demonstrated. For Rician fading, it is found that the capacity of the system with a Rician factor of 2 dBis reduced by 13 percent as compared to the capacity of the non-fading case. For shadowed Rician fading, three shadowing scenarios are considered: light, average, and heavy. It is shown that the light and the average shadowing scenarios provide only a slight decrease in the capacity, while the heavy shadowing scenario renders a capacity identical to that for the Rayleigh fading case. Finally, for Nakagami fading the capacity is found to decrease by 50 percent as the fading parameter is reduced to 0.5. The performance of a cellular frequency-hopped spread-spectrum multiple access system is studied under an indoor environment. It is demonstrated how the system capacity, given in terms of the number of users per cell, is affected by the number of cells in the system. Also, the influence of the delay spread, which is the result of multipath propagation, is investigated. The analysis focuses on a worst-case scenario where a user receives both the desired and interfering signals with equal power levels. This scenario applies to both the downlink and the uplink. It is shown that the system capacity is reduced drastically as the number of adjacent interfering cells increases from one to three. Previous work concerning the indoor multipath propagation assumed that the number of paths is fixed, the path delays are uniformly distributed, and the path gains are equal. In this dissertation, a more realistic channel model derived from actual impulse response measurements by Saleh and Valenzuela is employed. The model consists of clusters of rays with constant cluster and ray arrival rates and power-delay time constants. The system performance is shown to be affected strongly by the change in the power-delaytime constants, yet only slightly influenced by the variation in the arrival rates of the rays and clusters. In addition, the degradation in the system performance due to the delay spread becomes more severe as the transmission rate increases.

Download or read book Frequency Hopped Spread Spectrum Systems Have a Larger Multiple Access Capability The Effect of Interfering Signals with Unequal Power Levels written by Evaggelos Geraniotis and published by . This book was released on 1988 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report we present a new method for the evaluation of the probability of error of uncoded frequency-hopped spread-spectrum multiple-access (FH/SSMA) communications. For systems with binary FSK modulation, the method provides an accurate approximation and a tight upper bound to the bit error probability; for systems with M -ary FSK modulation, it provides tight upper bounds to the symbol error probability. This method relies on the integration of the product of the characteristic function of the envelope of the branch of the BFSK demodulator, which carries the desired signal, and of the derivative of the characteristic function of the envelope of the other branch; it can achieve any desirable accuracy and the computational effort required for its evaluation grows linearly with the number of interfering users. In the M -ary case, tight upper bounds based on the union bound and the results of the binary case are derived. Keywords: Frequency hopping, Spread spectrum, Multiple access, and Error control coding. (RH).

Download or read book Performance Analysis of Multi Channel and Multi Traffic on Wireless Communication Networks written by Wuyi Yue and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the rapidly increasing penetration of laptop computers and mobile phones, which are primarily used by mobile users to access Internet s- vices like e-mail and World Wide Web (WWW) access, support of Internet services in a mobile environment is an emerging requirement. Wireless n- works have been used for communication among fully distributed users in a multimedia environment that has the needs to provide real-time bursty traffic (such as voice or video) and data traffic with excellent reliability and service quality. To satisfy the huge wireless multimedia service demand and improve the system performance, efficient channel access methods and analytical methods must be provided. In this way very accurate models, that faithfully reproduce the stochastic behavior of multimedia wireless communication and computer networks, can be constructed. Most of these system models are discrete-time queueing systems. Queueing networks and Markov chains are commonly used for the p- formance and reliability evaluation of computer, communication, and m- ufacturing systems. Although there are quite a few books on the individual topics of queueing networks and Markov chains, we have found none that covers the topics of discrete-time and continuous-time multichannel mul- traffic queueing networks. On the other hand, the design and development of multichannel mul- hop network systems and interconnected network systems or integrated n- works of multimedia traffic require not only such average performance m- sures as the throughput or packet delay but also higher moments of traffic departures and transmission delay.

Download or read book Multiple Access Capability of Frequency Hopped Spread Spectrum Revisited An Exact Analysis of the Effect of Unequal Power Levels written by and published by . This book was released on 1988 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper we present a new method for the evaluation of the probability of error of uncoded frequency-hopped spread-spectrum multiple-access (FH/SSMA) communications. For systems with binary FSK modulation the method provides an accurate approximation and a tight upper bound to the bit error probability; for systems with M-ary FSK modulation it provides tight upper bounds to the symbol error probability. This method relies on the integration of the product of the characteristic function of the envelope of the branch of the BFSK demodulator, which carries the desired signal, and of the derivative of the characteristic function of the envelope of the other branch; it can achieve any desirable accuracy and the computational effort required for its evaluation grows linearly with the number of interfering users. In the M-ary case tight upper bounds based on the union bound and the results of the binary case are derived.

Download or read book Performance Analyses of Frequency hopped Spread spectrum Multiple Access Systems in Fading Environments written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Binary Frequency hopped Spread spectrum Multiple access Communications Systems written by Evaggelos A. Geraniotis and published by . This book was released on 1980 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Direct sequence Spread spectrum Multiple access Communication Via Fading Channels written by David Edward Borth and published by . This book was released on 1979 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of biphase direct-sequence spread-spectrum multiple-access (SSMA) communication for a general class of fading channels is investigated. The channels considered are those for which the channel output consists of a strong stable specular signal plus a faded version of this signal. Such channels are the result of a transmission medium which gives rise to a major stable communication path and a number of additional weaker communication paths. The fading channel is modeled as a general is modeled as a general wide-sense-stationary uncorrelated-scattering (WSSUS) channel -- a model which is general enough to exhibit both time and frequency selectivity and to impose no restrictions on the fading rate. A discussion of the important parameters of the WSSUS channel is given and two important classes of WSSUS channels are developed from the general fading channel model; time-selective fading channels and frequency-selective fading channels. In analyzing the performance of direct-sequence SSMA communications via fading channels two measures of system performance that are considered are average signal-to-noise ratio at the receiver output and the average probability of error. (Author).

Download or read book Performance Evaluation of Frequency Hopped Spread Spectrum Multi Hop Networks written by J. W. Gluck and published by . This book was released on 1988 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Primary and secondary multiple-access interference processes are characterized for multi-hop packet radio networks, in which users are assumed to be Poisson-distributed in the plane and to use frequency hopped spread-spectrum signaling with a receiver-oriented assignment of frequency-hopping patterns. The throughput per node and the average forward progress are then evaluated for frequency-hopped multi-hop networks that employ (i) random forward routing with fixed transmission radius (RFR) and(ii) most forward progress routing with fixed transmission radius (MFR). The optimal average number of neighbors and transmission radius are derived for these cases when Reed-Solomon forward-error-control coding with minimum distance decoding or binary convolutional coding with Viterbi decoding is employed.

Download or read book The Probability of Multiple Correct Packet Receptions in a Multireceiver Frequency Hopped Spread Spectrum System written by and published by . This book was released on 1991 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report we develop exact expressions and approximations for the probability of exactly l correct packet receptions in a group of m receivers, given that k packets are transmitted simultaneously from users employing frequency-hopping spread-spectrum (FH/SS) and Reed-Solomon (RS) coding. This quantity is essential for the design and performance evaluation of multiple-access protocols in spread-spectrum packet radio networks. The evaluations are carried out for MFSK modulation with noncoherent demodulation and various types of RS minimum-distance decoding with erasures and/or errors decoding. Packet synchronous FH/SSMA systems that are hop-synchronous or hop- asynchronous are considered. The exact expressions developed have computational complexity that grows exponentially with m, thus making their evaluation for large m prohibitive. In light of such difficulties, two approximations are considered: one based on Gaussian multivariate distributions with linear computational requirements in m and k, and another based on the assumption of independent receiver operation (IROA), which has minimum computational complexity. Extensive comparisons of the approximations with the exact results establish their validity over different ranges of the system parameters. (Author).

Download or read book Spread Spectrum Communications Handbook Electronic Edition written by Marvin K. Simon and published by McGraw Hill Professional. This book was released on 2001-09-22 with total page 1250 pages. Available in PDF, EPUB and Kindle. Book excerpt: The acknowledged Spread-Spectrum Bible the most complete reference in the field! INCLUDESCD-ROM CONTAININGTHE ENTIRE BOOKIN FULLY-SEARCHABLE PDF Spread-spectrum systems have found important commercial applications in CDMA cellular networks and wireless personal communication networks. Communications engineers and technicians now have ready access to a wealth of spread-spectrum information in this exhaustive handbook the most comprehensive and authoritative compendium on spread-spectrum systems available anywhere. Written by recognized authorities in the field, the Handbook presents both theoretical basics and practical applications, providing succinct, results-oriented solutions to engineering problems. Starting with basic concepts and system models, the book covers: Anti-jamming communication systems Coherent direct-sequence systems Non-coherent frequency-hopped systems Coherent and differentially coherent modulation techniques Pseudonoise acquistion and tracking in direct sequence receivers Time and frequency synchronization of frequency-hopped receivers Low probability of intercept communications In addition, it offers an in-depth look at multiple access communications and positioning systems and discusses the growth of spread-spectrum applications. INCLUDES CD-ROM CONTAINING THE ENTIRE BOOK IN FULLY SEARCHABLE PDF

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 Spread Spectrum Multiple Access Systems Performance Analysis written by Jawad Ahmad Salehi and published by . This book was released on 1984 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: