Mode-selective OTH radar: Experimental results for one-way transmission via the ionosphere

This paper reports results of an experimental program called the Mode Selection Experiment which was designed to demonstrate ionospheric propagation mode selectivity on transmit over a one-way skywave propagation path. This corresponds to the transmitter-to-target part of the two way propagation path used in OTHR. The purpose of the experiment was to show that MIMO radar techniques can be used to construct multiple simultaneous non-causal adaptive range dependent transmitter beams. Such beams are applied to selectively illuminate desirable ionospheric propagation paths while simultaneously nulling undesirable propagation paths and do so with a differing beampattern for each range cell in the OTHR range coverage.