Beam-Reconfigurable Aperture Antenna by Stretching or Reshaping of a Flexible Surface

This letter presents a beam-reconfigurable superstrate antenna with a periodic flexible surface composed of an array of liquid-metal-filled microchannels inside a polymer. Two beam-reconfiguration techniques are used here: 1) stretching the surface along one axis where the radiation pattern depends on the elongation percentage; and 2) reshaping the surface to concave/convex where the pattern depends on surface state. Elongation and reshaping can split the broadside beam to two beams up to ±55° and ±58° off-broadside, respectively. This technique can be used as a simple low-cost alternative to electronic tuning that requires integration of an array of switches/varactors into the surface and hinder the fabrication of large-scale tunable surfaces and aperture antennas.