High Data Rate, Reliable Wideband HF Communications Demonstration

Abstract- Assured beyond line-of-sight (BLOS) communications is challenging yet essential for our warfighters. Military and civilian systems rely on a combination of high data rate satellite connectivity as well as low data rate High Frequency (HF) skywave communications. While satellite communication provides high data rate connectivity, there are vulnerabilities that may degrade or disrupt service. To ensure critical communications are maintained, we are investigating the capability of higher bandwidth and higher data rate HF communications applying polarization diversity Multiple-Input Multiple-Output (MIMO) concepts. In addition, we are developing a multi-mode wideband HF channel simulator. We have successfully demonstrated short-hop (< 75 km) one-way HF skywave communication by simultaneously transmitting independent messages on two orthogonal circular polarization channels (O- and X-modes) for increased capacity and reliability. The communication waveforms we developed include higher capacity and bandwidth alternatives to the wideband waveforms in MIL-STD-188/110C Appendix D. In this paper, we demonstrate the results of our over-the-air (OTA) experiments and compare our performance against theoretically-predicted capacity for each waveform. We also describe the wideband HF channel simulator