Research on GMI-STBC Precoding in Ground-to-Air Data Link

The ground-to-air data link system is used for the connection between the airborne platform and the ground radio system, which needs to have the advantages of high reliability, strong anti-interference ability and high transmission rate. The multipath effect exerts a substantial influence on communication quality when the airborne platform and the ground station are at low elevation. To address this issue, this article proposes the GMI-STBC precoding which utilizes channel block diagonalization and space-time coding to ensure reliable transmission of ground-to-air data link within the same time-frequency resource. Channel block diagonalization transforms the channels between multiple airborne platforms and the ground station into parallel sub-channels that do not interfere with each other and STBC coding sends multiple copies of the data stream which are orthometric over multiple antennas to improve transmission reliability.