HF skywave MIMO radar: The HILOW experimental program

In the paper we report on an experimental program undertaken by the Defence Science and Technology Organisation and partners during the period from early 2006 to late 2007. The focus of the program was to investigate MIMO radar use in over-the-horizon radar. The program revealed that a specific MIMO radar technique: non-causal radar-transmit beamforming, can be applied to this radar class. Examples of this technique were demonstrated, including non-causal fixed transmit beamforming as well as non-causal adaptive transmit beamforming and non-causal direction-of-departure estimation. This is the first case where practically useful adaptive transmitter beamforming has been demonstrated in OTHR.