Maximally flat nonrecursive digital filters

In a recent letter, coefficients for a maximally flat nonrecursive transfer function were obtained via a special solution to the Hermite interpolation formula. This letter, however, shows how these coefficients can also be obtained by a simple `classical? method that sets derivatives of a rational function to zero.     

Coefficients of maximally flat nonrecursive digital filters

A general method is presented for determining the coefficients of maximally flat nonrecursive digital filters. Recursive relations with integer coefficients are derived for these coefficients by explicit calculations imitating Crout's method for solving the linear equations obtained by setting the derivatives of the symmetric, linear phase transfer function to zero at w = 0 and w = π. For a given order of the filter, the amount of computation required in this method is uniformly the same for any combination of permissible degrees of flatness at w = 0 and w = π.     

Least-squares design of higher order nonrecursive differentiators

A method is described that can be used to design non-recursive linear-phase higher order differentiators that can perform differentiation over any frequency range. The method is based on formulating the absolute mean-square error between the amplitude responses of the practical and ideal differentiator as a quadratic function. The coefficients of the differentiators are obtained by solving a set of linear equations. This method leads to a lower mean-square error and is computationally more efficient than both the eigenfilter method and the method based on the Remez exchange algorithm. Design of differentiators based on minimization of the relative mean-square error is also carried out. Finally, the method is extended to the design of frequency selective higher order differentiators     

Design of nonrecursive digital moving-target-indicator radar filters

This letter describes the design methods for a class of non-recursive digital m.t.i. filters with a multiple zero at z = 1 and an equiripple passband. Some examples of these responses are given, together with the filter coefficients.     

Design of nonrecursive digital filters with linear phase

A new class of selective nonrecursive digital filters with independently prescribed equiripple passband and stopband attenuation and linear phase is obtained by numerical solution of a set of nonlinear equations. Some examples are given, and a comparison is made of the new solutions and those previously known.     

Design of two-dimensional nonrecursive filters based on frequencytransformations

Presents a simple and efficient method to design 2-D zero-phase nonrecursive filters based on frequency transformations. The method involves the formulation of an error along the desired contour in a quadratic form. It is shown that the method results in scaling-free transformation coefficients     

Design of nonrecursive digital filters with minimum phase

A method is described of transforming nonrecursive filters with equal-ripple attenuation in the passband, stopband and linear phase into those with minimum phase and half the degree, but again with equal-ripple attenuation in the passband and stopband.     

非递归式决策树在动力计量计费系统中的应用

决策树算法的实现往往采用面向对象语言工具来实现,与数据库中的结构通常存在一定的差异,需要进行大量的数据转换。现在充分利用数据库中表结构特点和存储过程中PL/SQL语法的强大性及灵活性,采用一个动力计量计费系统中的数据,快速、有效且非递归地实现了决策树C4.5算法中的节点生成、扩展与剪枝主要过程;并进行了规则抽取。应用结果表明,该算法的实现方法具有一定的高效性、稳定性和普适性。     

Chebyshev approximation for linear phase nonrecursive digital filters

A procedure has been developed for the design of nonrecursive digital filters with prescribed passband and stopband amplitude characteristics. The proposed procedure is based on an efficient algorithm utilizing the simplex method of linear programming. The design algorithm yields equiripple approximation and it is an alternative to the one which is based on the Remz exchange algorithm. The design procedure allows exact specifications for arbitrary passband and stopband edges. Furthermore, no prior knowledge of the degree of the filter is required. To demonstrate the potential of the design algorithm, several examples with different requirements are worked out and a sample is presented. The obtained results show that the design procedure performed very well where the various parameters of the filter were taken into consideration.     

Further results on maximally flat nonrecursive digital filters

Starting with the Krawtchouk series representation of maximally flat FIR lowpass filters, a class of monotone bandpass filters is derived and exact design formulas are given.     

Explicit formula for filter function of maximally flat nonrecursive digital filters

A general formula for the filter function of maximally flat f.i.r. digital filters using modified Krawtchouk polynomials is presented. This formula permits a direct calculation of the filter weights. It is especially advantageous for either high or low passband/stopband width ratios.     

A nonrecursive signal integrator using a parallel CCD structure

In view of its advantages in certain situations over a recursive arrangement, the CCD implementation of a nonrecursive integrator is considered. Transfer inefficiency effects make it virtually essential to adopt a parallel-transfer approach. An implementation is proposed which requires only commercially available CCD delay lines together with conventional analog and digital techniques for driving and addressing the CCDs. An experimental simulation has established the feasibility of this approach. Investigations of the distortion inherent in one version of the integrator and of the integration improvement attainable are in good agreement with theory.     

New integer programming scheme for nonrecursive digital filter design

A new mixed-integer linear programming objective function for optimising an f.i.r. linear-phase digital filter is presented. In comparison with the conventional objective function, the new one has the advantages of reducing the number of delays and/or the coefficient wordlength.     

Properties of nonrecursive digital filtered ternary maximal length pseudo-random sequences

It is shown that a filtered ternary m-sequence has no skewing in amplitude distribution, zero autocorrelation function, and the cross-correlation between the sequence itself and the sequence squared is also zero. Some useful properties of ternary m-sequence are also listed.     

An architecture for autonomic security adaptation

Communication is the grounding principle of nowadays complex applications where the functionalities of the overall system are much more powerful then the ones of the isolated components. The task of keeping the communication system operable is highly critical due to the configuration complexity and the need for manual administration. Autonomous configuration mechanisms offer a compelling solution for the communication problem. We present an architecture for the autonomous configuration of secure, layer independent, end-to-end connections in this paper. The Extensible Security Adaptation Framework (Esaf) separates the particularities of communication setups strictly from the communication usage by the applications. Applications are unaware of the utilized security mechanisms and the complex configuration thereof. Protocols and security primitives can be easily introduced into the system whereas others might be disabled due to vulnerabilities without the need to modify existing programs. Moreover the setup can adapt to changing environments dynamically during runtime.     

Performance comparisons for nonrecursive digital filters with nonlinear phase characteristics

This letter presents a comparison between the performance, in terms of ripple and transition bandwidth, of nonrecursive digital filters with arbitrary phase characteristics and those with a linear phase response. Results are given which show that filters can be designed to have an arbitrary phase response, yet give as good a gain response as filters with linear phase.     

A nonrecursive Newton-Euler formulation for the parallelcomputation of manipulator inverse dynamics

The paper focuses on the inverse dynamics formulation of manipulators that is suitable for parallel computation, and a corresponding nonrecursive Newton-Euler formulation is presented. In order to illustrate its potential parallelism, a simple parallel scheduling scheme is proposed, and the parallel computational efficiency for the inverse dynamics of the basic three links of a PUMA 560 robot is analyzed. Compared with other algorithms, the theoretical computation cost of this parallel algorithm, in which factors such as communications overhead are ignored, is smaller