Application Of Membrane Computing In Optimal Digital Filtering Design

Digital filter plays an important role in the digital signal processing,with a widely range of theoretical and practical application.The essential characteristic of the digital filter is a device which can make the useful signal as much as possible all through,while maximally suppresses the useless signal.Due to the structure and function of digital filter,the traditional design methods have been difficult to meet the requirements of the performance parameters of digital filter,thus restricting the development of the digital filter design.Membrane computing is a novel kind of distributed parallel computing models,also known as the membrane system or P system,whose idea and mechanism are inspired from the structure and functioning of living cells as well as the cooperation of the cells in tissues or higher order structures.In recent years,the application research of membrane computing theory in a variety of real-world engineering problems has received widespread attention,and numerous research results have obtained.This dissertation discusses the application of membrane computing models in digital filter design,focusing on the design problem of the adaptive IIR and FIR digital filters.The design problem of digital filter is considered as a class of parameter identification problems.This dissertation systematically discusses how to use the structure,functioning,and evolution-communication mechanism of P system to propose a new class of digital filter design methods.The main innovations of this dissertation are summarized as follows:(1)An IIR digital filter design method based on P system is proposed.Firstly,a ring tissue-like P system is designed,and the parameters of the transfer function of IIR filter are regarded as the objects of the elementary membranes,meanwhile,the evolutionary mechanisms of the genetic algorithm(selection,crossover and mutation rules)are used to evolve the objects of the elementary membranes,and the communication rules of tissue P system are used to realize sharing and co-evolution between objects,so as to realize the optimal design of adaptive IIR digital filter.(2)A FIR digital filter design method based on P system is proposed.The star tissue P system is designed as its computing framework,while the impulse response coefficients of the filter are regarded as the objects in the elementary membranes.The velocity-position model of PSO is used to evolve the objects and inherent communication mechanism is used to share the objects between different elementary membranes,so as to determine the optimal filter parameters.