Effective packet transmission scheme for real-time situational awareness based on MIL-STD-188-220 tactical ad-hoc networks

In this paper, we propose an effective packet transmission scheme for real-time situational awareness (SA) in MIL-STD-188-220 based tactical ad-hoc networks. This standard is the Interoperability Standard for Digital Message Transfer Device Subsystems of American Department of Defense. In military communication networks, there are both Command and Control (C2) and SA messages. The C2 messages are comparably regarded as more important than SA messages. However, the SA messages are essential to make a common operational picture (COP) to increase battlefield effectiveness. The uplink SA messages are transmitted by each station in the lower echelons, and then the gateway station that can join the upper echelon relays the packets to the upper gateway station. At this time, if every station in the intra-network tries to send messages to the gateway station, the network efficiency decreases by the unintended delay and congestion at the gateway position. To overcome this problem, we adapt the Type 3 connectionless and coupled acknowledgement operation mode in MIL-STD-188-220. The gateway station initiates the uplink SA transmission to the other stations with Type 3 operation mode, and each corresponding station sends its own SA packet instead of an ACK packet. This can possibly reduce the overhead and congestion by eliminating access competition at the gateway position. The proposed scheme is thoroughly examined by simulation method, and the results show that the proposed scheme significantly reduces the packet delay time and improves the performance of MIL-STD-188-220-based military systems.