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Mixed Signal Detection, Estimation, And Modulation Classification, Yang Qu
Mixed Signal Detection, Estimation, And Modulation Classification, Yang Qu
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Signal detection, parameter estimation and modulation classification are widely applied to many areas and plays a very important role in civilian and military, such as bio-science, criminal psychology, communication engineering, radar system, electronic warfare and so on. In the civilian field, with the increasing number of wireless electronic devices and higher transmission data rate demand, the problem of spectrum congestion becomes more and more highlighted and urgent. In recent years, wireless industry has shown great interest in Cognitive Radio (CR) and Dynamic Spectrum Access (DSA) network, whose primary function is to use limited frequency bands to transmit own signals without …
Frequency Domain Processing Based Chaos Communication For Cognitive Radio, Daniel Y. Sundersingh
Frequency Domain Processing Based Chaos Communication For Cognitive Radio, Daniel Y. Sundersingh
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Chaotic systems are deterministic non-linear dynamical systems which have intrinsic properties such as: irregularity, aperiodicity, and are impossible to predict over long periods of time. Cognitive radio on the other hand, has emerged recently as a powerful means to tackle the spectrum congestion problem. The goal of this thesis is to combine the benefits of the chaos communication system with the cognitive radio to create a robust, highly secure, flexible chaotic cognitive radio system. We first begin with a short survey of chaotic communication and cognitive radio technology. Then we compare chaotic waveforms to other conventional PN sequences and show …
Ici Reduction Methods For Mc-Cdma Systems, Meng Wu
Ici Reduction Methods For Mc-Cdma Systems, Meng Wu
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Multi-carrier code-division multiple-access (MC-CDMA) is an important multiple access candidate for 4G wireless communication system. While MC-CDMA provides high performance and high capacity in frequency selective fading channels, it is very sensitive to the signal distortion, especially the Inter Carrier Interference (ICI). We apply self-cancelation and a frequency transmission paradigm to MC-CDMA system to improve the sytem performance in an ICI rich environment. Furthermore, we combine the frequency transmission paradigm FD-MC-CDMA with ICI cancelation. Also, we apply all these three schemes into non-contiguous OFDM and non-contiguous MC-CDMA systems in simple Cognitive Radio communication environments and present the simulation results. Theoretical …
Intelligent Spectrum Sensor Radio, Omer Mian
Intelligent Spectrum Sensor Radio, Omer Mian
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A cognitive radio is a radio with built-in intelligence that makes it able to utilize the radio frequency spectrum more efficiently by adapting to the changing conditions and frequency availability. In this thesis a spectrum sensor radio is designed that detects transmissions in FM band and determine the range of used and unused frequencies within the band. The radio then starts a transmission on a frequency among the available frequencies. This intelligent radio system design is implemented using the Universal Software Radio Peripheral and GNU Radio with a program written in python that uses a number of GNU Radio modules …
Non-Cooperative Modulation Recognition Via Exploitation Of Cyclic Statistics, Eric C. Like
Non-Cooperative Modulation Recognition Via Exploitation Of Cyclic Statistics, Eric C. Like
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This research proposes and evaluates a feature based modulation classification system designed to discriminate between AM, BFSK, OFDM, DS-CDMA, 4-ASK, 8-ASK, BPSK, QPSK, 8-PSK, 16- PSK, 16-QAM, and 64-QAM signals without a priori knowledge of critical signal parameters, including carrier frequency, symbol rate, or phase offset, among others. The classifier is based on the principles of cyclostationarity and leverages cyclic statistics to make its classification decision. The classification process is performed in a hierarchical process in order to exploit the lower variance of lower order cyclic statistics before making use of the higher order cyclic statistics. The initial classification is …