| The usage of electrical power distribution networks for accessed areas intelecommunications, called Powerline Communication (PLC) has become more and moreattractive in recent years. It has a number of advantages that attract great interest for thedevelopment of electrical market and business opportunities. In particular, the powerlinenetworking uses the existing power distribution lines. Nodes are already availablethroughout the household, making the PLC easy-to-use, low cost solution and compellingchoice. Unfortunately, due to the considerable differences between power distributionnetworks and conventional communication mediums, it remains difficult to implement ascheme that models the Powerline channel behavior adequately. The PLC is a noiseoriented environment for data communications and several factors present technicalchallenges to using power distribution lines for data communication. Besides the low passcharacteristic of cables and the frequency selective fading, the impedance mismatching, thesignal reflection and the impulse noises crucially affect the Signal to Noise Ratio (SNR).The performance of the powerline receiver is significantly degraded by the Inter SymbolInterferences (ISI) caused by different propagation delays of the multi-paths, the non-constant amplitude and the non-linear phase response of the channel. Due to the topology ofthe PLC itself, the signal will often experience attenuation and time varying effects thatdegrade the quality of the transmission. From a technical approach, this thesis addresses these challenges through the uniquecombination of OFDM hardware design, software implementation and the entropy conceptmanipulation based on the Renyi information theory. In this thesis, we present possibilities of applying PLC in the communication accessnetworks. A concise summary of the present state of the theory and practice of OFDM forpowerline is presented. The complete powerline channel characterization and transferfunction with multi-path propagation effects is described. A robust and adaptivetransmission OFDM scheme able to mitigate the powerline channel drastic effects isillustrated. We proposed a coupling unit topology and design methodology which couldprovide gain equalization and wideband mitigation of the effects of low impedance loads on iPLC at frequency ranging from 0.1 to 30 MHz. By inserting a special impedance matchingcircuit at the input of this coupling unit and by using alternative broadband matchingtechnique based on the combined micro-strip transmission-line, we maximized thepowerline network signaling. This technique reduces the signal distortion and harmonicsgeneration to meet certain safety standards for electromagnetic interference. The OFDM software algorithm and physical implementation technique for powerline isdeveloped. This software is visual C++ based graphical human-machine interfaceapplication. It provides a comprehensive and integrated data control, monitoring andtransmission system. This includes functions such as displaying and storage of incomingand outgoing communication signals. Other features include facilities to display or inputmessages, to visualize the system parameters such as the communication speed, the signalbandwidth and sub-carriers spacing. The interface between the transmission system andPLC network at the required intermediate frequency is obtained by adding appropriate ISAcard PCI and PLC coupling unit to the basic configuration. The IFFT plan moduleretrofitted in this application presents the advantage to speed up the IFFT computationaccording to the hardware system structure. Furthermore, we investigate the application of error entropy minimizationalgorithms for equalizer to mitigate the powerline channel drastic effects. The probabilitydensity function of the equalizer error sequence is estimated using Parzen windowingmethod and the Renyi's quadratic entropy is minimized...
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