Investigating the Effect of Realistic Leaky Coaxial Cable Setting on Its Radiation Pattern in Communications-based Train Control

Leaky coaxial cable is widely used in the wayside system as an antenna to distribute the stable wireless signal to the onboard system in the communications-based train control. The common practice in obtaining the high gain communication is to align the main lobes, i.e. beams, of the onboard system's antenna and the leaky coaxial cable (wayside system's antenna) by referring to their ideal radiation patterns. This paper investigates how the realistic leaky coaxial cable setting distorts such the ideal beam and causes the beam mismatch loss between the antennas using both measurement and electromagnetic simulation approaches. Then, this work points out the way of exploiting such distortion to obtain higher communication gain.