Southampton Photonics Announces Smallest Multi-channel Dispersion Compensating Grating.

Business Editors/High-Tech Writers

Optical Fiber Communications 2002

Booth 2371 Hall D

ANAHEIM, Calif.--(BUSINESS WIRE)--March 19, 2002

Precise Chromatic Dispersion and Dispersion Slope Management

for 10-Gbps and 40-Gbps Optical Networks

Southampton Photonics today announced the smallest available multi-channel Dispersion Compensating Grating (DCG).

Measuring only 180mmx 6.5mm in packaged format, the BragNet(TM) DCG can compensate for chromatic dispersion in up to four optical network channels simultaneously and individually. It uses a chirped Fiber Bragg Grating (FBG) design to match the dispersion slope of any fiber type to within 99 percent accuracy per channel and could be used for producing ultra-small sub-band or full-band compensation modules. An unpackaged, fiber version will be ideal for use in tuneable systems.

Supplied either as a packaged device for use in fixed wavelength compensation applications, or in fiber format for use in tuneable compensation modules, the high power handling capability and small size of the BragNet DCGs will offer many advantages to network equipment designers. They feature a wide range of compensation values from 200 to 2000ps/nm, an insertion loss of <1.5dB, and can operate over the C and L-bands.

Chromatic dispersion is an increasing problem in optical networks and caused by the various wavelengths which make up a single optical data pulse travelling at slightly different speeds down the fiber. As network data rates increase to 10Gbits/sec and beyond, this dispersion causes the pulses to overlap, an effect which worsens with distance travelled. The result is that the receiver can no longer distinguish the logic '1's from the '0's causing degradation of the data. Traditionally, the solution has been to use Dispersion Compensating Fiber (DCF), although this cannot compensate for each individual constituent wavelength, and it is limited by its power handling capability and intrinsic high loss characteristics.

Using Southampton Photonics' DCG approach means that the dispersion slope of each individual wavelength can be very accurately compensated at the receiver end, which enables higher data rates and more channels over longer distances. In many applications, the BragNet DCGs, with their very high power handling capability and low insertion loss, can be used to complement DCF and offer a means of compensating for chromatic dispersion on a per wavelength basis.

The BragNet DCGs are available in one, two or four wavelength formats and all have channel spacings of 100GHz. The packaged versions are housed in athermal cylindrical packages measuring only 6.5mm x 180mm. Fixed wavelength dispersion compensating modules (DCMs) are a primary application. For example, a 32 channel compensation system could be produced from only eight 4-channel DCGs which would represent a very large space saving over comparable methods. Alternatively, the DCGs can be supplied in unpackaged fiber format where they are ideal for use in stretched or thermally tuned applications.

The BragNet DCGs represent a natural product extension for Southampton Photonics as Marketing Director, Vince Sykes, outlined: "We introduced the world's most accurate Fiber Bragg Grating with a channel spacing of 25GHz at last year's OFC, and the dispersion compensating gratings are a natural extension of this breakthrough technology. They will give subsystem designers enormous flexibility; they can use between one and four channel packaged devices to build the smallest, most cost-effective, multi-channel compensation modules available, or they can use the unpackaged gratings in tuneable systems."

About Southampton Photonics

The company manufactures in-fiber optical components and subsystems based on its Application Specific Fiber Platform which allows the manufacture of reliable, high-performance in-fiber components and subsystems in volume. SPI's expertise is in specialty fiber, fiber Bragg grating design and fabrication, as well as amplifier and laser technology. These core technologies form the basis of the company's state-of-the-art components and subsystems, and make optical systems and networks more flexible, powerful and less expensive. Southampton Photonics' in-fiber technology enables optical networks to transport more bits, over more channels, with greater accuracy, at a lower cost.

Supplied either as a packaged device for use in fixed wavelength compensation applications, or in fiber format for use in tuneable compensation modules, the high power handling capability and small size of the BragNet DCGs will offer many advantages to network equipment designers. They feature a wide range of compensation values from 200 to 2000ps/nm, an insertion loss of <1.5dB, and can operate over the C and L-bands.

BragNet(TM)is a registered trademark of Southampton Photonics

NOTE TO EDITORS: In the third paragraph there is a "less than" symbol before "1.5dB". This symbol may not appear properly in some systems.