The use of heterogeneous antenna arrays in experimental HF-MIMO links

To date, MIMO research has focussed predominantly on communications within the VHF, UHF and SHF bands and has not been widely addressed in the lower frequency bands. This paper describes the results of experiments that have been performed to investigate the feasibility of utilising MIMO techniques within the HF radio band, with particular emphasis on the use of compact, heterogeneous antenna arrays.