Researchers at UCSB have helped create a new method to increase wireless transmission speeds in data centers by up to 30 percent.

Scientists discovered that metal plates placed on the ceiling of data centers better transmit signals from directional antennas, thereby increasing the efficiency and speed of wireless communication.

Although wireless connections are not novel, previous systems required that Wi-Fi stations sending and receiving data have a line-of-sight connection. By angling the stream of data upward, signals can bounce off the ceiling. As a result, signals from densely packed areas can be transmitted regardless of their location within a data center.

To demonstrate this effect, UCSB associate computer science professor Heather Zheng and her team used a 60 gigahertz wireless device in spite of the fact that this type of data transmission is typically sensitive to interference between the transmitter and the receiver.

“Any obstacle larger than 2.5 mm can block the signal,” said Zheng. To avoid such reception problems, Zheng’s team used directional antennas to improve communication.

Rather than create a mesh network that could potentially further complicate route destination, Zheng and her team next placed flat metal plates on the ceiling of data centers.

“When we put a radio on top of each rack — a stack of servers used in data centers — these radios can block each other’s signal,” said Zheng. “This is because 60 gigahertz radio signals are highly sensitive to obstacles.”

Accordingly, the plates were especially important since they provide near perfect reflection and therefore reduce signal interference. Additionally, the metal plates absorb light, which ensures that signals do not bounce back up or scatter around the antenna, while electromagnetic absorbers are placed on top of racks to prevent unwanted reflection.

To test their theory, Zheng and her associates placed reflectors on the ceiling of a 160-rack data center and observed changes in transmission speed and efficiency compared to previous techniques. The performance improved by 0.5 terabytes per second.

Currently, IBM is working on using wireless technology in data centers. However, the first commercial products using this technology will not be available until next year.