An antenna system (10) for receiving satellite signals in a vehicle exhibits a radiation pattern (11). The antenna system (10) includes a plurality of parasitic elements (18) which are electrically connectable together using linking switches (20). The geometry of the radiation pattern (11) changes as the linking switches (20) are activated and deactivated. Control of the linking switches (20), and thus the geometry of the radiation pattern (11), is based on the geographic location of the antenna system (10). Thus, the radiation pattern (10) can be steered based on geographic location to enhance signal reception. The geographic location may be obtained automatically via a GPS receiver (30) or manually via a user.