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An investigation into filters utilising coupled transmission lines.

Johnstone, G. G. (1995) An investigation into filters utilising coupled transmission lines. Doctoral thesis, University of Surrey (United Kingdom)..

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This thesis addresses itself to the solution of a number of problems which arise in the development of Radio Frequency filters, particularly those involving coupled transmission lines as resonant elements. The text is divided into a number of sections dealing with individual topics. After a brief description of Darlington filter design principles, there is an account of the pivotal role of quarter wave sections and their vital part in the realisation of high frequency filters. This is followed by the development of new material relating to equivalent circuits of physical lines in terms of quarter wave sections, and its application to improvements in the design of wide-band filters. There follows an account of a new procedure for calculating the dimensions of comb-line and inter-digital filters. This section includes a new proposal for the inversion of Getsinger's procedure to permit the calculation of rectangular rod dimensions and spacings from given electrical data. There is also an algorithm for use with round rods which circumvents the tedious manual interpolation procedure devised by Cristal. There follows an investigation of and a proposed solution to a long-known but unexplained discrepancy existing between the calculated and measured pass-band width of the class of comb-line filters. With the new procedure the discrepancy reported previously to be of the order of 10% is eliminated. Finally, experimental evidence is adduced to verify the algorithms outlined in the preceding chapters.

Item Type: Thesis (Doctoral)
Divisions : Theses
Authors :
Johnstone, G. G.
Date : 1995
Contributors :
Depositing User : EPrints Services
Date Deposited : 09 Nov 2017 12:17
Last Modified : 20 Jun 2018 11:31

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