by josh perry, editor
teams of researchers from ibm research (zurich, switzerland) and the european union-funded addapt consortium have used complementary metal-oxide-semiconductor (coms) technology, standard for high-volume chip manufacturing, to produce a novel optical receiver that achieved aggregate bandwith of 160 gb/s through four optical fibers.
photo of the test setup (top) and the packaged receiver (bottom).
(alessandro cevrero/ibm research)
according to a report from the optical society of america (osa), this is the “fastest data transmission speed to date” and the new receiver also features link power-on/off functionality and can reach phase-lock in eight nanoseconds, which is another record.
the rapid power-on/off will reduce energy consumption on a chip or within an interconnected system and power would only be needed when data packets are transmitted through the optical link. the report added, “the novel design, packaged with an 850-nanometer photodiode array, targets low-cost vcsel-based optical links for datacenter interconnects.”
the report continued, “today, link utilization in datacenters is less than ten percent for 99 percent of the links. this means only ten percent of the links’ work time is actually used for transmitting user data, while the rest of the time is wasted by sending idle data packets that missing information. to improve power efficiency in optical interconnect system, the researchers developed the rapid on/off functionality for the receiver, so that links can be powered off during idle time and powered back on when the data is ready to be transmitted.”
in order to achieve the fast power-on time, the researchers designed the receiver with four identical channels associated with a link protocol that is equipped with smart analog circuits, which align the receiver’s clock with the arrival of the incoming data. the receiver detects the optical signals and turns the system on and off.
“they observed correct power cycling across a 109 power cycle, and that the receiver operates error free at 40 gb/s second yielding 160 gb/s aggregated bandwidth over multi-mode fibers,” the report added. “the experimental data also showed that ten-percent link utilization corresponds to 85-percent power saving on the receiver.”
researchers will continue studying the system’s effectiveness with a complete optical interconnect system and increase data transmission to 56 gb/s per channel.
the research will be presented at the optical networking and communication conference (ofc 2018) in san diego, calif. in march.