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In this paper, a Weighted Least Square based designing of fractional delay FIR filter using Genetic Algorithm is proposed. In this method, Genetic Algorithm is implemented to evaluate the closed form error function. This helps in speeding up the process of filter design and achieving globally optimized final solution. Three design examples are given to illustrate the results of proposed approach. These examples demonstrate the effectiveness of proposed approach as compared to the existing filter design methods.

A method of designing a fractional order digital FIR differentiator using Type-III Discrete Cosine Transform is put forward in this paper. The Grunwald-Letnikov definition of Fractional calculus is implemented to calculate the filter coefficients of fractional order differentiator. Then, different windows are applied to modify the filter response that improve the accuracy of the linear phase FIR filter design. The frequency response of the designed filter is a very close approximation to the ideal response which clearly indicate the validity of our approach. Finally, the design examples compare the results with different windows and demonstrate that the design error with the proposed method are smaller than that with the conventional DCT technique. Extensive simulation results affirm that the proposed approach using DCT-III outperform its counter part DCT-II not only in terms of magnitude response but also in terms of phase response.

In this paper, we implement low complexity odd order variable fractional delay filter. In odd order, filter is designed by type-2 subfilters (odd order even symmetric) and type-4 subfilters (odd order odd symmetric) but type-2 subfilters gives zero magnitude response at ω=π due to which there is a large approximation error in the filter design .To reduce this error replace type-2 subfilters with the cascading of type-1 subfilters and half delay filter. In this type of hybrid odd order VFD FIR filter consist of three type of FIR filter (Type-1 subfilters Type-4 subfilters and Type-2 half delay filter). To further reduce the complexity of FIR filter optimize the coefficients of the subfilters.

This paper presents a performance based comparison of some of the major compressed domain color image enhancement techniques with special emphasis on the Color Enhancement By Scaling the DCT Coefficients technique [CES-DCT] and Color Enhancement By Scaling the Wavelet Transform Coefficients technique [CES-DWT]. The CES technique is found to be simple but more effective than some of the existing enhancement techniques suggested earlier. The novelty of the CES technique is that it treats the chromatic components, while previous techniques treated only the luminance component. The CES-DWT utilizes the advantages of the wavelet transform and is found to be capable of improving both global and local contrast as well as preserving color consistency. The results of all previous compressed domain enhancement techniques along with that of the CES are compared with respect to those obtained by applying a spatial domain color enhancement technique that provides very good enhancement. The CES-DWT technique is found to provide better enhancement compared to other compressed domain based approaches (even better than CES-DCT) and is computationally more efficient than the spatial domain based method.

In this paper, a fractional order digital differentiator is designed by using Inverse multiquadric radial basis function (RBF). First, the RBF interpolation approach is described. Then, the non-integer delay sample estimation is derived by using RBF approach. Next, the Grunwald-Letnikov derivative and non-integer delay sample delay are applied to obtain the transfer function of the proposed method i.e. fractional order digital differentiator. The design accuracy of the proposed method is better then the conventional methods like examples Time domain least squares method, Fractional sample delay method and Frequency response approximation method.

The work presented in this paper is concerned with the designing of a variable fractional delay (VFD) FIR filter using least square method encompassing all delay values p. First, the frequency response, e-jωp, of the VFD filter is approximated using power series expansion of an exponential function and then, it is represented in terms of frequency response of the differentiator. Next, the proposed least square method adopts a novel cost function which includes all the fractional delay values. Finally, design and application examples are given to illustrate that the proposed least square method have better design accuracy and significantly reduction in magnitude error with the same degree of complexity than existing least square methods.

In this paper, new designs of first order microwave integrator are proposed by using six equal length transmission line sections. One of the proposed designs is obtained by changing the normalizing frequency of existing design of microwave integrator and the other design is obtained by optimizing the characteristic impedances of transmission line sections. The simulated results are almost close with the ideal ones in the frequency range of 3GHz to 5GHz for one of the designs and 4GHz to 10GHz for other design.