In automotive application there is a strong need for compact multifunctional microwave antennas for example for cellular phones, GPS and, in the USA, satellite radio. The mutual coupling between the antennas leads to alterations in the antenna pattern which, in particular with the antenna for the SDARS-satellite system, is not accepted by the providers. In this paper it is shown how the impact of two phone antennas on the SDARS-antenna can be reduced to an negligible amount.