摘要:

An accelerated procedure for the design of equiripple nonrecursive digital filters is described. The new procedure entails two techniques. The first technique is a selective search for the maxima of the error function, and it replaces the exhaustive search proposed by Rabiner, McClellan and Parks. It leads to a large saving in the number of function evaluations. The second technique is a more effective approach for the rejection of superfluous maxima of the error function. It can lead to a significant reduction in the number of iterations. The two techniques together lead to an overall saving in the amount of computation in the range 55 to 83%, depending on the filter specifications.

DOI:10.1049/ip-g-1.1982.0001

出版商:IEE    

年代:1982

数据来源: IET

摘要:

A unified approach is presented for the design of two classes of nonminimum phase transfer functions providing an optimum Cheby̅shev passband magnitude response and approximating to a constant delay over the larger part of the passband in terms of a mini-max norm. In one of these classes, the numerator polynomial of the transfer function is of even degree, since all its zeros possess quadrantal symmetry, or are located in pairs symmetrically about the origin. The other class, based on pole-zero cancellation in the left half of the complex frequency plane, offers more flexibility in practical design by permitting the passband magnitude ripple and the delay error (or the delay bandwidth) to be specified independently. In addition, the latter yields, in many practical applications, a more economical solution from the point of view of both the complexity of the realised network and the ease of tuning, as demonstrated by some suitably chosen examples.

DOI:10.1049/ip-g-1.1982.0002

出版商:IEE    

年代:1982

数据来源: IET

摘要:

The paper describes a multiplying D/A converter implementation of a programmable waveform generator. Its particular advantages over other schemes are its inherently glitch-free operation, and a reduction in the number of words required to define a low distortion waveform.

DOI:10.1049/ip-g-1.1982.0003

出版商:IEE    

年代:1982

数据来源: IET

摘要:

The realisation of sharp cutoff lowpass filters by cascading low-Q3rd-order blocks is proposed. An example shows that it is possible to reduce the poleQs (and, consequently, the overall sensitivity) without increasing the number of blocks, with respect to the usual approach employing cascaded 2nd-order blocks.

DOI:10.1049/ip-g-1.1982.0004

出版商:IEE    

年代:1982

数据来源: IET