Radiating Properties of 1-D Bidirectional Leaky-Wave Antennas

We analyze radiation from bidirectional one-dimensional leaky-wave antennas (1-D LWAs), from an original perspective. As is known, when the aperture is infinite, the radiation pattern changes considerably for certain combinations of the phase and the attenuation constants. These specific values identify the boundaries between different radiating regimes. In this work, we thoroughly explain the evolution of the beam through all the radiating regimes, and then evaluate its beamwidth with original analytical formulas. The relevant case of a finite-size aperture is considered as well. In this case, we show that the boundaries between the radiating regimes change as the radiation efficiency changes. The evolution of these boundaries as a function of the radiation efficiency is found by numerical means. These results allows for a rigorous and comprehensive description of the radiating behavior of practical 1-D bidirectional LWAs.