Internally-Controlled Memristor-Based Modulator With Application In Power Line Communication

Power line communication(PLC)is an old system of communication that dates back as far as the development of power grids.PLC systems offer a wider reach and cheaper alternative to wireless communication and other means of transmitting communication signals.However,this system of communication is limited by a number of factors including noise and impedance mismatch.To mitigate these challenges several techniques and modulation strategies have been explored by scholars.A very simple modulation technique is the amplitude shift keying(ASK)modulation.This is a modulation technique that despite its own shortcomings is still being used in the communication industry today.This technique is applied in this study in the design of a PLC system.Another technology of interest in this study is the memristor,a nonlinear electrical component whose memristance is dependent on the history of the electrical properties across its terminals.The memristor,among others,finds use in areas of neuromorphic applications and digital signal processing circuits.The memristor is not yet commercially available and as such emulators made up of active devices are used by scholars for research purposes.These emulators developed by scholars are often limited by their frequency operating range hence affecting their possible areas for application.Also,they often require additional control circuits to control the memristance of the memristor.In this study,a floating memristor emulator is explored and its frequency operating range is analyzed.It was realized that by changing a parameter in the emulator circuit its frequency range can be increased.More so,being made of active devices it could be seen that the pinched loop which is an acid test for the memristor emulator could not be observed at 100 k Hz with respect to the changed circuit parameter.To control the memristor emulator a DC signal is superimposed with a periodic signal,and the memristor emulator can be made to maintain a fixed memristance value at either of two states depending on the polarity of the DC signal being superimposed.This understanding of the behavior of the memristor emulator helps inform and guide its application.The switching property of the memristor emulator is employed in the design of an internallycontrolled floating memristor emulator-based ASK modulator.A binary data signal to be modulated on a carrier wave is converted to a bipolar signal by a preprocessor which becomes a very good control signal for the memristor emulator when inserted within the ASK modulator.The controlled switching of the memristor emulator brings about an ON OFF keying of the data signal onto a carrier signal which when filtered by a high pass filter realizes an amplitude shift keying modulated signal.The designed memristor emulator based ASK modulator is applied in the design of a PLC system.A coupling circuit void of an impedance matching transformer is designed and used to couple the ASK modulator and demodulator to a PLC system.By analyzing the signal output of the demodulator,the performance of the designed PLC system can be analyzed.It was realized that for low data rates of 100 Hz and 500 Hz the system showed good data transmission both for when there was a power signal and when there wasn’t.However,for 1k Hz data signals the performance of the system reduced and data loss was observed on the demodulator output.The study was done using simulation results from PSPICE and experiment results obtained after the circuit was built and tested.The data obtained both via simulation and experiment was plotted using ORIGIN.The results from both the simulation and experiment were in agreement.Chapter one is the introduction which contains a background of both the memristor and the PLC.The chapter two discussed and analyzed the memristor emulator circuit.In the chapter three the internally controlled floating memristor emulator was discussed.In chapter four the memristor based power line communication system was designed and its performed analyzed.The chapter five contains the conclusion.