Empirical Formula for the Electric Field Calculation in Rectangular Slots on Leaky Coaxial Cable

An empirical formula for calculating the electric field distribution in rectangular slots on leaky coaxial cable (LCX) is derived. With the assistance of the formula, the complicated electromagnetic simulation can be avoided, and people who have little knowledge about the electromagnetic field are also possible to design the LCX. The coefficients in the formula are determined by curve-fitting of a large amount of data obtained from numerical method for various structural parameters of the LCX. The empirical formula is valid for LCXs with characteristic impedances of 50 Ω. Results obtained from the empirical formula are compared with those given by numerical method and experiments, and good agreement between them can be seen. The proposed formula provides a simple and effective means to calculate the electric field in rectangular slots on the LCX, which is very useful to the investigation of the radiation characteristics and to the design of the LCX.