Innovative AWG cascade technology for next-generation WDM applications

Broadex Technologies has launched its new AWG Cascade technology. The products comprise two synchronised AWGs arranged in series on a single chip, produces ultra-low insertion loss, flat-top bandpass shape and single-mode output.

The first product developed by the company to use the AWG Cascade technology is a multiplexer/demultiplexer chip for four-channel CWDM applications in datacentre transceivers. This new product provides best in class insertion loss as low as 2dB over the full 13nm flat-top passband with a true single-mode output, all within a compact 9mm x 3mm footprint. As data rates continue to increase, single-mode optical transmission becomes increasingly desirable. In WDM applications, the single-mode output beam from the AWG Cascade structure can be focussed to a much smaller diffraction-limited spot on ever-shrinking high-speed photodetector active areas, which eases assembly tolerances as well as improving signal strength. The single-mode beam also allows for highly efficient coupling directly from the AWG Cascade chip to silicon photonics grating couplers and waveguides.

The AWG Cascade chips will initially be available with layouts of a single 1x4 AWG Cascade and a double 2x8 Double Density (DD) AWG Cascade pair. These chips are suitable for use either as a multiplexer/demultiplexer pair or in 8-channel applications such as FR8 or LR8. The curved AWG Cascade structure can also be laid out efficiently to provide up to 64 individual AWG Cascade structures on a single chip, ideal for CPO used in next-generation multi-Terabit applications.

AWG Cascade products are available in various forms, from wafers to connectorised chips and modules, to suit customer needs. Customised solutions include angled input and output polishing, port locations, alignment features, loopback waveguides, chip size and connector types.

“Broadex’s AWG Cascade technology is a game-changer for next-generation WDM applications. It enables best in class optical performance whilst at the same time provides lower packaging cost when compared with traditional AWG and Thin Film approaches,” said Dr Henk Bulthuis, head of design and research at Broadex Technologies UK, who led the development of this technology. “Individual AWG Cascade structures can also be easily stacked and extended for multi-channel and multi-port configurations. In fact, the number of advantages grows with the number of devices on the chip.”