Showing papers by "Mohammed Abo-Zahhad published in 1997"
TL;DR: In this article, the authors proposed a method based on extracting an orthogonal matrix from the filter state matrix, resulting in structures that need n Givens rotations and at most n + 1 multipliers.
Abstract: A novel method is proposed for the synthesis of low-sensitivity digital filters meeting any prescribed transfer function. The method is based on extracting an orthogonal matrix from the filter state matrix, resulting in structures that need n Givens rotations and at most n + 1 multipliers. Thus the proposed realization is canonic in the sense that it has the same degrees of freedom as the original transfer function. It is also shown that when the filter transfer function is a reciprocal reactant bounded function, it can be decomposed into allpass functions that need only Givens rotations for their realization. As the basic module in the realization is the Givens rotation, the CORDIC computation algorithm can be applied directly. This means considerable savings in computation time and complexity. It also results in structures that are less sensitive to the effects of finite word length. Illustrative examples, including the design and synthesis of linear phase selective filters, are given to show the extremely low sensitivity with respect to finite word length of the resulting realizations when compared with other methods.
4 citations
TL;DR: In this paper, a double-lattice form of selective linear phase digital filters is described for the design and implementation, and it is shown that these filters are optimum in the sense that all available degrees of freedom are used in adjusting the filter parameters to meet the specified characteristics.
Abstract: A method is described for the design and implementation, in a double-lattice form, of selective linear phase digital filters. It is shown that these filters are optimum in the sense that all available degrees of freedom are used in adjusting the filter parameters to meet the specified characteristics. The designed filters, apart from satisfying the linear phase requirement, exhibit equiripple loss response over both the pass- and stopbands. A novel computationally efficient method based on computing the complex cepstrum is proposed for the construction of orthogonal double-lattice structures that realize the designed filters. It is based on the important property of cepstrum functions, namely decomposing mixed sequences into both minimum and maximum phase sequences. Illustrative examples are given to support the theoretical analysis.
1 citations