CONTRIBUTIONS TO THE THEORY OF WAVE GUIDES

Part I deals with the problem of determining the field due to a source of radiation inside a semi-infinite rectangular wave guide closed at one end by a plug, the current distribution in the source being regarded as known. Both the walls of the guide and the plug are treated as being perfectly conducting. Three different methods of solving the problem are given. The radiation resistance is then deduced from energy considerations. In particular, an expression for the radiation resistance of a linear antenna perpendicular to the wider face of the plug, fed at the point of entry, is derived, it being assumed that the antenna current is sinusoidal and that only the fundamental H-wave is transmitted by the guide.In Part II, one of the methods of paper I is extended to the case of a guide of arbitrary cross section, and the general problem of the calculation of radiation resistance and reactance is discussed.In Part III, a number of formulae for the radiation resistance of antennae of various shapes, with various assumed current distributions, in rectangular and circular guides, are given.In Part IV, explicit calculations for the impedance of a linear antenna in a rectangular wave guide are given. Further numerical calculations relating to the same problem, from the point of view of matching and sensitivity, have been made by Messrs. Chien and Pounder, but are not reproduced here.