Big Bear Networks selects IBM's SiGe technology for Photronic Signal Processing products

Big Bear Networks has adopted silicon germanium (SiGe) process technology from IBM Microelectronics for its forthcoming Photronic Signal Processing (PSP) family of 10- and 40-Gbit/sec transponder and subassembly products.

IBM Microelectronics' high-volume silicon foundry in Burlington, VT, will serve as the manufacturing facility for the PSP products, which will begin shipping later this year.

Big Bear's SiGe-based PSP products will take the form of 10-Gbit subassemblies and transponders for long-haul applications; and 40-Gbit transponders for cross-office,
metro core/inter-office facility, and long-haul transmission. PSP technology is designed to overcome the impairments that degrade data-transmission signals over fiber-optic links, enabling telecom carriers to deploy longer and faster fiber links with minimum capital and operational expenditure.

Big Bear has been working with IBM for the past 18 months to apply SiGe technology to its PSP product designs, says Dr. John Paul Mattia, Big Bear co-founder and chief technical officer. Big Bear has already produced a number of operational 10- and 40-Gbit devices based on the process.

IBM's SiGe technology was selected after Big Bear evaluated various competing process technologies, including Indium Phosphide (InP).

"In our early development phase we implemented several designs in both SiGe and InP, initially believing that the inherently higher speeds of InP would be required for high performance 40-Gbit products," admits Mattia. "However, after side-by-side comparison, we found that SiGe not only produces circuits that achieve the mandatory high performance, but also lets us easily integrate the active intelligence needed to overcome fiber impairments."

The ability of SiGe to integrate millions of transistors on a chip was a key factor in its selection, Mattia noted, particularly since Big Bear's PSP technology incorporates a high degree of embedded intelligence. "Since InP circuits are presently limited to 5,000 transistors, this clearly was not the process platform of choice to integrate all the functionality required by the intelligent opto-electronic physical layer. SiGe lets us augment standard functions such as clock and data recovery at 10- and 40-Gbits with the integrated signal processing necessary to address the impairments associated with high-speed fiber transmission."

For more information about Big Bear Networks (Milpitas, CA), visit the company's Web site at www.bigbearnetworks.com.