Amplifier Enables 100G Network Operation

Thanks to a new transimpedance/variable gain amplifier, electronics manufacturers are now able to build 100 Gigabit-per-sec (gps) optical networks for use in the nation's Internet backbone.

Designed and built by Inphi Corp., the new amplifier is a critical enabler in the effort to deliver the greater speed and bandwidth that's going to be needed as more mobile smart phones reach mainstream consumers.

"This technology enables a factor of 10 increase in Internet backbone capacity," says Loi Nguyen, founder and vice president of Inphi Corp. Nguyen adds that he expects the technology to go beyond Internet backbone applications, which serve as hubs for all Internet traffic, and eventually migrate down to metropolitan network applications.

The new amplifier, known as the Inphi 2850TA, is considered significant because it enables electronics makers to build coherent receivers, which offer the advanced phase modulation that's necessary for the creation of 100G optical networks.

            "To ship that many bits through a single wavelength, you need the most advanced modulation technology available," Nguyen says. "That's coherent detection."

During the operation of a coherent receiver, optical signals are converted to electrical, amplified by the 2850TA, and then sent to a high-speed analog-to-digital converter (ADC). The transimpedance/variable gain amplifier is critical to that process because signals that are sent to the ADC must be free of distortion for the system to be able to work properly at 100 gps.

Nguyen claims that Inphi's amplifier is the first to combine the high linearity, high bandwidth, low noise and low power needed for 100 gps operation.

The transition to so-called "100G" is important for makers of mobile phones because the industry is said to be running out of bandwidth at a time when many mainstream phones now have Internet capabilities. Several mobile phone manufacturers have indicated they plan to skip directly from 10G to 100G technology over the next few years.

"It's a fundamental technological transition to go from 10G to 100G in an optical communications network," Nguyen says. "And you need the right receiver technology to do it."