Data rate change algorithms for efficient HF communications
Vasco Sequeira, Maria Paula Queluz, António Rodrigues, Jose E. Sanguino, Pedro Grifo · 2018
The HF radio band is very important for military operations, enabling communications beyond line-of-sight. To deal with the variability of the Ionosphere, several technologies have emerged in the last years, like automatic Link Quality Analysis (LQA), Automatic Link Establishment (ALE) and Data Rate Change (DRC) algorithms. In this paper, two DRC algorithms are assessed - namely, Trinder and RapidM - and improved versions of these algorithms are proposed: Avoiding Cut-Off State (ACOS) and Bit Error Optimization (BEO). The first proposal reduces the occurrences of link cut-offs (corresponding to bit error rates higher than 10-3); the second proposal, besides increasing the link availability, eliminates data rate oscillations. When compared to the original versions of the algorithms, both proposals showed significant improvements in all of the considered link assessment metrics, either when evaluated in a simulation environment, or in real field propagation tests.