A leaky transmission line method for the analysis of the microstrip line traveling wave antennas

We present a numerically efficient and fast technique which can be used for design and optimization of traveling wave radiating structures. This technique is similar to the leaky cavity method which has successfully been applied to the analysis of the microstrip patch antennas (Lo et al. 1979). It is based on the fact that the traveling wave antennas are essentially leaky wave radiators. The traveling wave RF current over the body of these antennas, which are usually in the form of long transmission lines, radiates electromagnetic power continuously and therefore decreases, in amplitude, exponentially (Nakano and Hirose 1994). In the proposed "leaky transmission line model" for this antenna, the per unit length resistance of the line is modified to include the power lost to the radiation in addition to the other losses.