As evidence that wireless communications are moving to ever higher frequencies, this week researchers from A*STAR's Institute of Microelectronics (IME) announced development of the first compact high performance silicon-based cavity-backed slot (CBS) antenna that operates at 135 GHz. The antenna demonstrated 30 times stronger signal transmission at 135 GHz as compared with on-chip antennas, and is only 1.6 mm x 1.2 mm--about the size of a sesame seed.
A*STAR says it’s the smallest silicon-based CBS antenna reported to date for ready integration with active circuits. It can be combined with other millimeter-wave building blocks to support wireless speeds of 20 Gbps, more than 200 times faster than present day Wi-Fi.
“The novel use of polymer filling enables 70 percent antenna size shrinkage and a record high gain of 5.68 dBi at 135 GHz,” said Dr. Hu Sanming, a key researcher from IME and leader of the antenna project. “By filling the antenna cavity with polymer instead of air, we can achieve a flat surface for subsequent processing by standard technology that is amenable to mass production.”
Dr. Je Minkyu, principal investigator of the Integrated Circuits and Systems Laboratory at IME also noted that the group had also designed a three-dimensional architecture for integrating the antenna with active circuits, thus creating a fully-integrated wireless millimeter wave-system-in-package that offers high performance, a reduced footprint and minimal electromagnetic interference.