The good folks at the Air Force Research Laboratory have been working on a radar that uses liquid metal to allow for on the fly reconfiguration:
The US Air Force Research Lab (AFRL) is building antennas using liquid metal to enable changes to the size, shape, and functionality of the electrical wiring.
Currently, the research effort is using gallium, which is known for its use in radars (gallium arsenide and gallium nitride types) and sensors.
“What we are doing here is using the gallium as a metal itself,” Christopher Tabor, materials research scientist, AFRL, told Jane’s at the US Department of Defense (DoD) Lab Day, held on 18 May at the Pentagon in Washington, DC.
“Gallium by itself melts at about 87° Fahrenheit [30.5° Celsius]. If you blend in materials like Indium it becomes a eutectic alloy that will melt at much lower temperatures,” Tabor said. “So this is a conductive fluid below room temperature.”
Pre-designed channels inside structural composites are filled with liquid metal to produce an embedded, physically reconfigurable antenna, according to AFRL.
We are all familiar with liquid metals, as the liquid metal in “Mercury” thermometers is now the alloy Galinstan, an alloy of Gallium, Indium, and Tin, and is a liquid from around between -19° and 1300°C.
The theory here is that you could have a series of channels and valves (or perhaps fluidic controls) that would allow a radar to change its shape dynamically, which would eliminate the need for actuators found in more conventional radars.
I call this neat stuff.
I thought the whole point of phased array was you didn't have to do this stuff. I'm happy to be schooled on the subject…..
One of the disadvantages of phased array radars is that their performance drops off at larger look angles, so peak performance is typically in a 30-45 degree cone, while mechanically scanned radars have a 150-180 degree cone.
It's one of the reasons why the Gripen's Selex radar has that swashplate setup.
Other reason for the swashplate setup (and why the B-1 has an angled radar) is that it reduces RCS.
The ability to reconfigure geometry on the fly allows for the array to be reconfigured depending on the location of the threat.
Ah excellent, I thought you'd know. Thanks!