Lucent Technologies Introduces Integrated Circuits to Support High-speed Internet Access to Homes, Offices Over Passive Optical Networks

Business Wire, July 18, 2000

Business Editors & High-Tech Writers

ALLENTOWN, Pa.--(BUSINESS WIRE)--July 18, 2000

Lucent Technologies (NYSE:LU) Microelectronics Group, the world leader in communications semiconductors, today announced three new low-power integrated circuits (ICs) that enable transmission of voice, video and high-speed data signals over passive optical networks (PONs). PONs are a class of "fiber-to-the-home" or "fiber-to-the-curb" access networks that telephone and cable TV companies are starting to deploy to deliver voice, video programming and high- speed Internet access to homes and businesses.

The new ICs - a laser driver, receiver and clock data recovery IC - were designed by researchers at Lucent's Bell Labs and will be incorporated in PON components known as optical line terminals (OLTs) and optical networking units (ONUs). OLTs are installed at service provider facilities such as telephone company switching centers or cable TV head-ends. ONUs are installed in homes, apartment and office buildings, or in neighborhood distribution hubs (in fiber-to-the-curb configurations). Communications signals travel between the OLT and ONU over optical fiber, with signals being routed from one OLT to as many as 32 ONUs.

The term "passive" refers to the fact that there are no electrically powered components along the network path - only the endpoints (the OLT and ONUs) are powered. As a result, service providers consider PONs to be an economical and reliable solution for bringing digital video programming and high-speed Internet access over "the last mile" into homes and offices.

"Bandwidth capacity in the core transport network and office local area networks has been expanding to handle Internet-stimulated demand, but by-and-large, the access network remains a bottleneck for broadband digital services," said Dong Liu, strategic marketing manager for Analog Networking and Interface Products. "Service providers worldwide are eyeing PONs as an economical and viable solution to breaking this bottleneck and providing the needed capacity. By offering chips to this market, Lucent is spurring the design and manufacture of high- speed components that will hasten the deployment of PONs."

The three Lucent PON ICs together provide a systems approach to handling upstream broadband traffic at 155 megabits per second (Mbit/s). The laser driver transmits signals from the ONU (at the home or office end of the network) to the optical receiver in the OLT (at the head-end or central office). The optical receiver IC contains its own preamplifier and postamplifier circuitry. Both chips are optimized for burst-mode operation; that is, they handle short bursts of data at rates up to 155 Mbit/s. The clock data recovery IC located in the OLT has a burst-mode "first bit recovery" capability called QLOC(TM) recovery (for "quick lock on clock") to support the ultra-fast clock recovery specification in the PON full services access network (FSAN) standards. Together, the three ICs provide a burst-mode solution that is essential to PON upstream communication, which conventional continuous-mode ICs cannot handle.

"Unlike other circuit design approaches, these chips enable PON systems to recognize the first bit in a packet of data, compared to up to eight bits of data, which leads to more robust, high-performance systems," said Al Dunlop, director of the design principles research department at Lucent's Bell Labs.

In addition, the laser driver features patented digital automatic power control (DAPC) under burst mode operation, which ensures the transmitter has a well-controlled optical output power so that packets from different ONUs arrive at the OLT receiver with approximately the same amplitude. The laser driver, which operates at 50% of the power of conventional laser drivers, also has automatic detection capability to determine when the laser is close to end of its operating life. The ONU can then send an alert to the central office or head-end.

The optical receiver has burst mode threshold adjustment capability that allows the ONUs to be located at different distances from the optical splitter, but within the FSAN specification of 20 kilometers from the OLT.

The three ICs are available in sample quantities now, and are slated for volume production in October. Unit pricing in quantities of 10,000 is as follows: for the laser driver, US$25; for the receiver, US$23; and for the clock data recovery IC, US$28.

Lucent Technologies, headquartered in Murray Hill, N.J., USA, designs and delivers the systems, software, silicon and services for next-generation communications networks for service providers and enterprises. Backed by the research and development of Bell Labs, Lucent focuses on high-growth areas such as optical and wireless networks; Internet infrastructure; communications software; communications semiconductors and optoelectronics; Web-based enterprise solutions that link private and public networks; and professional network design and consulting services. For more information on Lucent Technologies, visit its Web site at http://www.lucent.com.