Dual band cavity-backed quarter-wave patch antenna

A light-weight, low cost, dual band patch antenna for use in a vehicle satellite communication system has been designed in accordance with a set of mechanical and electrical specifications. The initial design was based on a transmission line model of a quarter-wavelength flat element, which is connected to the ground plane by a perfectly conducting wall on one of its sides. The design was further refined by employing antenna modeling software based on the finite difference time domain (FDTD) method. To cover both the receive and transmit frequency bands, the matching network was designed by using a gradient optimization method, which used random initial guesses to minimize the VSWR of the antenna-matching network system.