US Patent 7119751 Dual-layer planar antenna

An antenna for receiving an RF signal from a satellite is preferably integrated with a window of a vehicle. The window preferably includes a first nonconductive pane and a second nonconductive pane laminated together with a PVB adhesive layer. A first conductive layer is disposed on one of the surfaces of the nonconductive panes and a second conductive layer is disposed on another of the surfaces of the nonconductive panes. The second conductive layer includes a main slot extending thereinto. The main slot defines a feed line region and ground plane regions. The second conductive layer also includes stub slots extending into the ground plane regions for antenna impedance matching and providing the antenna with a circular polarization.