Optimizing the Size of SAW filter using GA

This paper discusses the existing optimization techniques and then Genetic Algorithm has been applied as optimization technique in order to enhance the response. Surface Acoustic Wave Filters are particular Band Pass Filters which are currently used in electronic equipments for qualitative communication. Developers of SAW Filters have faced challenges that arise from design complications, limited practical upper frequency, high manufacturing costs, selection of waveguide material, filter dimensions, limited power handling and examining frequency characteristics corresponding to given specifications. The size of the SAW filter is also a main issue because frequency response of a filter depends on its size. The structure of Inter Digital Transducer (IDT) decides its frequency response. So, in order to have desired response, the structure must be known. The best structure is one for which the Frobenius norm distance is minimum. The structure includes the number of units to be cascaded and their positions. It is a combinatorial optimization problem. The paper presents Genetic Algorithm technique for finding the combinations of the IDTs for which the Frobenius norm distance is minimum. By obtaining desired frequency response at multiple frequency points, it results in reduction of size of the filter.