The tactical networks to support land operations have various unique features that come from the ends and means of military operations, and the area of operations. In general, the communication environments are considered a very poor due to the existence of enemy attack. In addition, it requires the elaborate quality of service (QoS) to guarantee the preemptive priority, and the collaboration to achieve a common goal. For these features, the well-known technologies for commercial networks are not suitable for immediate application to tactical networks. Thus, the development of a new protocol design or the modification of the existing ones is necessary.
This dissertation deals with the protocol design for tactical networks. We propose three MAC layer schemes for tactical multi-hop networks: 1) fast dynamic slot assignment (F-DSA), 2) artificial collision based dynamic slot assignment (AC-DSA), and 3) cooperative retransmission and relaying scheme (CR2). These schemes cover the network functions of network join and leave, reliable transmission and multi-hop delivery of packets. The proposed slot assignment schemes and transmission scheme are mutually compatible so that a various combination of these schemes can be used according to the network characteristics and administration policy.
For the fast network access, F-DSA simplifies the slot assignment process by using mini-slots to share control packets for short period. Meanwhile, AC-DSA exploits artificial packet collisions as a control message for slot assignment, which enables nodes with high priority to deprive a non-idle slot of nodes with low priority to guarantee quality of service requirement when no slots are available. CR2 exploit idle slots and wireless broadcast nature for efficient cooperative retransmission and relaying, which are activated adaptively according to transmission conditions, without any additional signaling overhead by fully distributed coordination mechanism.
We formulate analysis models for the each proposed schemes, which are validated by extensive simulations. The analysis and simulation results show that the proposed schemes improve the performance in terms of network access for a newly arrived node, throughput and delay in Rayleigh fading channels.
