A high frequency (HF) radio communications system is disclosed. HF radio communications system comprises a plurality of geographically-distributed HF radio sites comprising a corresponding plurality of receivers, each receiver of the plurality of receivers being configured to: (a) receive, via at least one antenna, respective HF signals throughout a HF band, and (b) directly and concurrently sample a subset of the respective HF signals to provide a respective stream of digital samples, the subset being the respective HF signals that are received over a plurality of HF channels within part of the HF band or all of the HF band; and a central processing server configured to receive a plurality of respective streams of digital samples from the plurality of receivers, being the respective stream of digital samples provided by each receiver of the receivers.