A.Y. Baraboshin, A.L. Buzov, A.D. Krasilnikov

This article is about using MIMO in HF-band. It is proven that traditional approaches shall not result in sufficient HF-band speed increase, and one of the most promising non-traditional approaches is MIMO technology, which allows to transfer data simultaneously over multiple subchannels using same frequency band. Known Alamouti scheme with two transmitting antennas is described. Approach to create coding matrix for three and six antennas is listed. Promising variant of building HF-band MIMO using multipolarized emitting systems, including triorthogonal emitters and circular antenna arrays based on these is described. Antenna system structure is listed and scheme to form six subchannels using polarization and elevation separation while controlling beam azimuth is discussed. It is proven that this solution allows data transfer speed increase, linearity increase and signal/noise ratio increase.