Abstract:

An antenna system is provided having switched directional antennas. The antenna system includes a first antenna for receiving signals within a first directional coverage zone, and a second antenna for receiving signals within a second directional coverage zone. According to one embodiment, the first and second antennas are located on a vehicle. The system has a device to detect orientation of the vehicle. The system further includes a receiver having control circuitry for controlling selection of the signals received from the first and second antennas based on orientation of the vehicle, location of one or more sources, and antenna coverage zones for the first and second antennas.

Description:

TECHNICAL FIELD

The present invention generally relates to antennas and, more particularly, to a vehicle mounted antenna system and method of selectively communicating signals with remote transmission sources, such as satellites.

BACKGROUND OF THE INVENTION

Automotive vehicles are commonly equipped with various signal communication devices such as audio radios for receiving broadcast radio frequency (RF) signals, processing the RF signals, and broadcasting audio information to passengers in the vehicle. Satellite digital audio radio (SDAR) services have become available that offer digital radio service covering a large geographic area, such as North America. Currently, a couple of satellite-based digital audio radio services are available in North America. These SDAR services are referred to as Sirius satellite radio which employs three satellites in elliptical orbit and XM satellite radio which employs two satellites in geo-stationary orbit. Both services receive uplinked programming which, in turn, is rebroadcast directly to digital radios that subscribe to the service. Each subscriber to the SDAR service generally includes a digital radio having a receiver and one or more antennas for receiving ...

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