摘要:

This paper examines the potential of integrated-circuit-based programmable transversal filters for baseband operation. The emphasis is on compact processors with an eventual aim of a single chip, monolithic (design suitable for a variety of signal-processing applications. Before hardware developments are treated, trade-offs between serial and parallel configurations of convolver are considered, together with their respective component requirements. It appears that for complete integration of a transversal filter module, the parallel approach is preferred. A study is made of the circuit elements of a particular realisation of an integrated analogue convolver in c.c.d./m.o.s. technology. All aspects of the design are considered and the description is focused around a prototype 64-stage programmable transversal filter. Several such units could be cascaded giving this integrated approach an enormous potential in applications where space and power are crucial, and high computing precision is not essential.

DOI:10.1049/ij-ecs.1978.0001

出版商:IEE    

年代:1978

数据来源: IET

摘要:

Consideration is given to recursive fixed-point digital filters employing a signal wordlength in the range of 4 to 8 bits. Experimentally determined values of roundoff-noise variance are found to deviate markedly from those predicted in the normal manner. Such deviation is caused mainly by correlations between signal and error sequences. A method is proposed whereby improved predictions of noise variance may be obtained in the case of first order filters. Finally, it is demonstrated that, when the ‘coefficient slicing’ realisation is used to realise filters with sufficiently quantised coefficients, such filters yield both a very low level of roundoff noise, and also excellent agreement between the predictions of a simple model and measured noise levels

DOI:10.1049/ij-ecs.1978.0002

出版商:IEE    

年代:1978

数据来源: IET

摘要:

A new two-stage approach to the computation of the discrete Fourier transform is described, which, relative to the fast Fourier transform (f.f.t.), can offer a number of distinct advantages: fewer inherent multiplications over a given range, no complex arithmetic for real data, and flexibility of output. The mathematical foundations and related algorithms are discussed in detail and a guide to the advantages over both the f.f.t. and the recently reported Winograd Fourier transform are included.

DOI:10.1049/ij-ecs.1978.0003

出版商:IEE    

年代:1978

数据来源: IET

摘要:

A circuit technique is proposed, based upon a parallel-structured system, that attempts to reduce the overall component cost required for a generalm-pole transfer function. The circuit uses justmnominally equal-valued capacitors, irrespective of the number of zeros. Whilst the zero sensitivity of the parallel structure is expected to be rather poorer than that for the cascade circuit, it has been found acceptable for the example described. The pole sensitivity is the same as that for the more conventional cascade structure.

DOI:10.1049/ij-ecs.1978.0004

出版商:IEE    

年代:1978

数据来源: IET

摘要:

A practical technique for the analogue simulation of the arbitrary nonlinear monotonic and nonmonotonic transfer characteristic is presented in this paper. Using operational amplifier and function generator with the monotonic transfer characteristic, any nonmonotonic function with the arbitrary slope is generated.

DOI:10.1049/ij-ecs.1978.0005

出版商:IEE    

年代:1978

数据来源: IET

摘要:

The optimum values to which to grow virtual elements are considered for four variants of the coefficient-matching technique for synthesising linear networks. Whilst relatively simple closed-form expressions are obtained in three cases it seems that a numerical linear-search procedure must be invoked in the remaining case.

DOI:10.1049/ij-ecs.1978.0006

出版商:IEE    

年代:1978

数据来源: IET

DOI:10.1049/ij-ecs.1978.0007

出版商:IEE    

年代:1978

数据来源: IET