This paper presents a rate adaptation algorithm for directional multicast communication in tactical networks. The proposed algorithm is based on the received signal strength indicator (RSSI) and delay constraint that are sent by receivers in the network. This feedback from receivers provides accurate real-time information about the current state of the communication channel so that the transmission rates can be varied to reduce the loss of the transmitted data packets. Typically, rate adaptation algorithms consider packet loss, modify frames in only the MAC layer, and accordingly change modulation scheme employed by the transmitter. In the proposed method, the modulation technique used for data transmission is changed according to the RSSI by considering the delay constraints of transmission to ensure satisfactory real-time performance. Simulation results show that the proposed method based on the IEEE 802.11a standard ensure good performance and reliability in terms of reduced the delay, increase throughput and the number of nodes that received data.
Available online: https://ieeexplore.ieee.org/document/7357427