A New Distributed Reservation Multiple Access Scheme for the AVPAC Channel

Aeronautical Radio, Inc. has proposed DRM A (Distributed Reservation Multiple Access) for the integration of voice and data on the AVPAC (Aviation VHF Packet Communication) channel, also known internationally as VDL (VHF Data Link). DRM A offers various interesting features; yet it has some limitations. In this report, we evaluate DRM A and extend it to make it more efficient and more suitable to the AVPAC mobile environment. First, we review the PRMA(Packet Reservation Multiple Access) protocol which is related to DRMA in several ways. Then, an improved algorithm that can increase the throughput of DRMA is proposed. We also propose a handoff mechanism for this protocol. Handoffs were not considered previously in Aeronautical Radio, Inc.’s DRMA documents, which were designed only to test the correctness of the mechanism.