Crossed Frame Antenna for Automotive Application for the New US Satellite Digital Audio Radio Service (SDARS)

SDARS antennas must meet the very strict specifications of the two providers Sirius and XM and many automotive aspects in addition. With some car producers the base of the antenna is coplanar with the roof, in other cases the antenna is mounted on a cast. The cast changes the antenna pattern considerably. For example at high elevation angles with a 9mm cast the antenna gain is reduced by 2dB in comparison to a situation where the antenna base is coplanar with the roof. This effect occurs in a similar manner with patch antennas. In this paper a crossed frame SDARS antenna is presented and it will be shown by which means the diagram can easily be modified and adapted to the specific mounting situation. This type of antenna can be used for compact diversity application as well.