Abstract This paper presents optimization method for synthesis of generalized high order microwave filters with arbitrary topology. The method utilizes local optimizer for coupling matrix determination. The synthesis procedure converges very fast as for a initial point is used a vector based on the Chebyshev all pole filter for the same degree of the filter. To validate the proposed synthesis method... This paper presents optimization method for synthesis of generalized high order microwave filters with arbitrary topology. The method utilizes local optimizer for coupling matrix determination. The synthesis procedure converges very fast as for a initial point is used a vector based on the Chebyshev all pole filter for the same degree of the filter. To validate the proposed synthesis method two numerical examples for resonant filters are computed. The frequency responses from the synthesis procedure and the theoretical responses show excellent agreement. Read More Read Less

Abstract Control and synthesis of sound source directivity have a significant position in modern acoustics. For this purpose, special sound sources that consist of independent element loudspeaker array are used. Sound source analyzed in this paper is a loudspeaker array in the form of dodecahedron. To generate different directivities, the loudspeaker array is fed independently with a few characteristic sets of signals.... Control and synthesis of sound source directivity have a significant position in modern acoustics. For this purpose, special sound sources that consist of independent element loudspeaker array are used. Sound source analyzed in this paper is a loudspeaker array in the form of dodecahedron. To generate different directivities, the loudspeaker array is fed independently with a few characteristic sets of signals. Special setup was established for radiation directivity measurements. For analyzing and presenting the results, a MATLAB application is developed. The measured directivities obtained by feeding of some of the loudspeakers with particular signals show interesting patterns of radiation. Read More Read Less

Abstract This paper proposes an optimal third-degree polynomial, which approximates Kronecker’s delta function with high precision. The polynomial is obtained by a new approximation method, called “method with compressed cosines”. The method is based on Chebyshev’s optimality norm. The polynomial is used for narrow bandpass IIR filter design. The filter’s selectivity depends on the parameter Q without increasing the polynomial’s order.... This paper proposes an optimal third-degree polynomial, which approximates Kronecker’s delta function with high precision. The polynomial is obtained by a new approximation method, called “method with compressed cosines”. The method is based on Chebyshev’s optimality norm. The polynomial is used for narrow bandpass IIR filter design. The filter’s selectivity depends on the parameter Q without increasing the polynomial’s order. With the proposed method an IIR filter with 5(6) multipliers, a very narrow passband and a high stopband attenuation can be designed. Read More Read Less