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.

Designedand built by Inphi Corp., the new amplifieris a critical enabler in the effort to deliver the greater speed and bandwidththat's going to be needed as more mobile smart phones reach mainstreamconsumers.

"Thistechnology enables a factor of 10 increase in Internet backbone capacity," saysLoi Nguyen, founder and vice president of Inphi Corp. Nguyen adds that heexpects the technology to go beyond Internet backbone applications, which serveas hubs for all Internet traffic, and eventually migrate down to metropolitannetwork applications.

The newamplifier, known as the Inphi2850TA, is considered significant because it enables electronics makers tobuild coherent receivers, which offer the advanced phase modulation that'snecessary for the creation of 100G optical networks.

"To shipthat many bits through a single wavelength, you need the most advancedmodulation technology available," Nguyen says. "That's coherent detection."

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

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

Thetransition to so-called "100G" is important for makers of mobile phones becausethe industry is said to be running out of bandwidth at a time when many mainstreamphones now have Internet capabilities. Several mobile phone manufacturers haveindicated they plan to skip directly from 10G to 100G technology over the nextfew years.

"It's afundamental technological transition to go from 10G to 100G in an opticalcommunications network," Nguyen says. "And you need the right receivertechnology to do it."