The impedance properties of narrow radiating slots in the broad face of rectangular waveguide: Part I--Theory

Theoretical results, valid at and away from resonance, for the impedance properties of the rotated series slot, the displaced series slot, and the longitudinal shunt slot have been derived by the use of variational expressions coupled with certain stored power considerations. The additional influence of finite wall thickness, an appreciable factor, is taken into account by a microwave network treatment. The results for the zero-thickness resistive elements become identical with those of Stevenson when the slot length is made equal to a half wavelength. The theoretical derivations are presented in Part I. In Part II, comparison is made with experimental data both previously available and specially taken in this connection. The effect of wall thickness and the distinction between slots of rounded and rectangular ends are also considered. The agreement between theory and measurement is reasonably good.