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Approved for public release; distribution is unlimited / This thesis examines the performance of the waveforms specified by the IEEE 802.11a wireless local area network standard when the signal is transmitted over a Ricean fading channel with AWGN and pulsed-noise interference. The pulsed interference is assumed to have constant average power and is either fading or nonfading. The probability of bit error is conditional on the received signal-to-noise power ratio, which is modeled as a random variable. The probability density function of this random variable is obtained either analytically or numerically for each modulation type, and the probability of bit error is evaluated as the expected value of the conditional probability. In one case, use is made of a new technique for the numerical inverse of the Laplace transform in order to evaluate numerically the signal-to-noise ratio probability density function. Due to the complexity of the analysis when both the signal and the interference are subject to Ricean fading, the analysis was simplified by assuming Ricean signal fading with Rayleigh interference fading and vice versa. The results of the analysis show that performance is affected by the degree of signal fading and also depends on the pulsed interference duty cycle. The signal-to-interference power ratio affects the way performance depends on these two factors. / Captain, Hellenic Air Force

by Yin-Man Lee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 82-[87]). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of MC-CDMA --- p.1 / Chapter 1.2 --- System Model --- p.3 / Chapter 1.3 --- Receiver Optimization --- p.7 / Chapter 1.4 --- Transmitter Optimization --- p.9 / Chapter 1.5 --- Nonlinearly Constrained Optimization --- p.10 / Chapter 1.6 --- Outline of Thesis --- p.11 / Chapter 2 --- Centralized Transmitter Optimization for MC-CDMA Systems --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Problem Development --- p.15 / Chapter 2.3 --- Lagrangian Optimization Approaches --- p.16 / Chapter 2.3.1 --- Penalty Function Method --- p.17 / Chapter 2.3.2 --- Barrier Function Method --- p.19 / Chapter 2.3.3 --- Powell's Method and Augmented Lagrangian Method --- p.21 / Chapter 2.4 --- Optimal FDMA System --- p.23 / Chapter 2.5 --- Modified Centralized Optimization Schemes --- p.25 / Chapter 2.6 --- Performance --- p.27 / Chapter 2.6.1 --- Typical Behavior --- p.27 / Chapter 2.6.2 --- Average Performance --- p.32 / Chapter 2.7 --- Summary --- p.38 / Chapter 3 --- Decentralized Transmitter Optimization for MC-CDMA Sys- tems --- p.39 / Chapter 3.1 --- Introduction --- p.39 / Chapter 3.2 --- System Model --- p.41 / Chapter 3.3 --- Optimization --- p.42 / Chapter 3.3.1 --- Receiver Optimization --- p.43 / Chapter 3.3.2 --- Single-user Transmitter Optimization --- p.44 / Chapter 3.3.3 --- Decentralized Transmission Scheme --- p.45 / Chapter 3.3.4 --- Multirate Transmission with Decentralized Transmission Scheme --- p.47 / Chapter 3.4 --- Performance --- p.48 / Chapter 3.5 --- Summary --- p.57 / Chapter 4 --- Performance Evaluation of Various Adaptive Transmission Schemes --- p.59 / Chapter 4.1 --- Introduction --- p.59 / Chapter 4.2 --- Comparison of Different Adaptive Transmission Schemes --- p.61 / Chapter 4.3 --- Adaptive Transmission Schemes with K > M --- p.64 / Chapter 4.4 --- Modified Adaptive Transmission Scheme with Graceful Degrada- tion in the SNR --- p.68 / Chapter 4.5 --- Summary --- p.71 / Chapter 5 --- Conclusions and Future Work --- p.73 / Chapter 5.1 --- Conclusions --- p.73 / Chapter 5.2 --- Future Work --- p.75 / A The Hungarian Method for Optimal Frequency Assignment --- p.76 / Bibliography --- p.82

Tsang Tin-Tak. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 78-80). / Abstract also in Chinese. / Chapter CHAPTER ONE: --- INTRODUCTION --- p.2 / Literature Survey --- p.3 / Project overview --- p.4 / Chapter CHAPTER TWO: --- SENSOR --- p.6 / Chapter 2.1. --- Background --- p.6 / Chapter 2.1.1. --- Piezoresistive effect --- p.6 / Chapter 2.1.2. --- Wheatstone bridge --- p.7 / Chapter 2.2. --- Strain Gauge --- p.10 / Chapter 2.2.1. --- Experimental setup for strain gauge --- p.11 / Chapter 2.2.2. --- Position of the strain gauge --- p.12 / Chapter 2.2.3. --- Selection of the value for the resistor to complete the bridge --- p.13 / Chapter 2.3. --- Pressure sensor --- p.15 / Chapter 2.3.1. --- Structure of pressure sensor die --- p.15 / Chapter 2.3.2. --- Modeling of the pressure sensor die --- p.17 / Chapter 2.3.3. --- Alternative application of the pressure sensor die --- p.20 / Chapter CHAPTER THREE: --- WIRELESS TRANSMISSION --- p.24 / Chapter 3.1. --- Introduction --- p.24 / Chapter 3.2. --- Analogue Transmission --- p.25 / Chapter 3.2.1. --- Transmitter (MC2833) --- p.26 / Chapter 3.2.2. --- Receiver (MC13135) --- p.29 / Chapter 3.3. --- Digital transmission --- p.30 / Chapter 3.3.1. --- Advantage of using Digital transmission --- p.30 / Chapter 3.3.2. --- Digital Transmitter and receiver 1 (H2000 & RX2020) --- p.30 / Chapter 3.3.3. --- Digital Transmitter and receiver 2 (TX2) --- p.32 / Chapter 3.4. --- Comparison between the three sets of transmitter --- p.34 / Chapter 3.4.1. --- Analogue Vs Digital --- p.34 / Chapter 3.4.2. --- Number of components (Complexity) --- p.35 / Chapter 3.4.3. --- Excepted size --- p.35 / Chapter 3.4.4. --- Transmitting distance --- p.36 / Chapter 3.4.5. --- Power supply --- p.36 / Chapter 3.4.6. --- Conclusion --- p.36 / Chapter 3.5. --- The detail investigation of HX2000 and RX2020/RX2056 --- p.37 / Chapter 3.5.1. --- Transmitting distance --- p.37 / Chapter 3.5.2. --- Shape of the received signal --- p.37 / Chapter 3.5.3. --- Orientation of the chips --- p.39 / Chapter 3.5.4. --- Conclusion for the transmitter --- p.39 / Chapter CHAPTER FOUR: --- ENCODING AND DECODING CIRCUIT --- p.40 / Chapter 4.1. --- Introduction --- p.40 / Chapter 4.2. --- Serial binary converter (MAX 1240) --- p.40 / Chapter 4.2.1. --- Features of MAX1240 --- p.41 / Chapter 4.2.2. --- Implementation of MAX1240 --- p.43 / Chapter 4.2.3. --- Method to decode the signal generated by MAX1240 --- p.46 / Chapter 4.3. --- Voltage-to-Frequency Converter (AD654) --- p.52 / Chapter 4.3.1. --- Advantages of using AD654 as the A/D converter --- p.54 / Chapter 4.3.2. --- Disadvantages of using AD654 as the A/D converter --- p.55 / Chapter 4.3.3. --- Method to read the frequency --- p.56 / Chapter 4.4. --- Frequency counter --- p.57 / Chapter 4.4.1. --- Schmitt trigger NAND-gate --- p.58 / Chapter 4.4.2. --- Ripple counter --- p.61 / Chapter 4.4.3. --- Implementation of the counter --- p.63 / Chapter 4.5. --- Conclusion --- p.66 / Chapter CHAPTER FIVE: --- INTERGATION OF THE THREE COMPONENTS --- p.67 / Implementation of the Circuit --- p.67 / Chapter 5.2. --- The result before transmission --- p.70 / Chapter 5.2.1. --- Analysis and Discussion for the experimental result (before transmission) --- p.72 / Chapter 5.3. --- The result after transmission --- p.74 / Chapter 5.3.1. --- Analysis and Discussion for the experimental result (after transmission) --- p.76 / Chapter CHAPTER SIX: --- SUMMARY --- p.77 / BIBLIOGRAPHY --- p.78

Thesis (Ph. D.)--Lehigh University, 2001. / Includes vita. Includes bibliographical references (leaves 93-101).

No description available.

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An Intelligent Network (IN) can be visualised as a central computer interconnected to the telecommunication network that allows the creation and deployment of services as consumer demand arises. Messages or information are transferred between the central processor and exchanges by a standardised form of signalling, known as Common Channel Signalling System Number Seven (CCS7). The thesis focuses on CCS7 performance, models and topologies. A requirement of the research entails the study of the CCS7 performance parameters: signalling delays and signalling network dependability. Signalling delays may be comprised of signalling message transfer delays within the message transfer part and queueing delays. Signalling network dependability usually include availability, reliability, maintainability and network robustness. For the purpose of modelling, the decomposition of the CCS7 message transfer part into subsystems is essential. A generic model for the message transfer part was used to implement certain functionalities of CCS7 in OPNET. OPNET (Optimised Network Engineering Tools) is a comprehensive engineering system capable of simulating large communication networks with detailed protocol modelling and performance analysis. The simulation software (OPNET) and performance parameters were used to analyse CCS7 networks resulting in the selection of a particular topology for a given region. The network structures analysed include the mesh topology, standard quad topology, hierarchical topology and Telstra's new topology. It was found that the mesh structure had the best simulated and availability/reliability results but was impractical for large networks due to the cost implications. This cost factor led to the selection of a hierarchical signalling system for Kwa-Zulu Natal. / Thesis (M.Sc.Eng.)-University of Durban-Westville, 1998.

No description available.