A new antenna, called a Plasma Silicon Antenna, or PSiAN,  promises superfast wireless networks.

It consists of thousands of diodes on a silicon chip. When activated, each diode generates a cloud of electrons — the plasma — about 0.1 millimeters across. At a high enough electron density, each cloud reflects high-frequency radio waves. By selectively activating diodes, the shape of the reflecting area can be changed to focus and steer a beam of radio waves.

PSiAN is small enough to fit inside a cellphone. The narrow beam means there is less “overspill” of radiation than with existing omnidirectional antennas.

As well as speeding up Wi-Fi, plasma antennas could also allow cars to come with low-cost miniature radar systems to help drivers avoid collisions. Their millimeter wavelengths could be used to “see” through fog or rain, and another set of antennas could listen for real-time updates on traffic and road conditions.

PSiAN could be commercially available within two years.