A satellite audio broadcasting system for mobile and fixed receivers at or near the earth's surface in geographic service areas at latitudes above about 30 degrees N or below about 30 degrees S include a satellite constellation of two or more satellites, each in its own geosynchronous orbit, with each...http://www.google.es/patents/US6223019?utm_source=gb-gplus-sharePatente US6223019 - Efficient high latitude service area satellite mobile broadcasting systems
Efficient high latitude service area satellite mobile broadcasting systems
