SAN JOSE,
Calif. — June 18, 2020 - NeoPhotonics Corporation (NYSE: NPTN), a leading developer
manufacturer of silicon photonics and advanced hybrid photonic integrated
circuit-based lasers, modules and subsystems for bandwidth-intensive, high speed
communications networks, today announced that it has completed experimental
verification of the transmission of 400Gbps data over data center interconnect
(DCI) ZR distances in a 75 GHz spaced Dense Wavelength Division Multiplexing (DWDM)
channel. NeoPhotonics achieved two milestones
using its interoperable pluggable 400ZR coherent modules and its specially
designed athermal arrayed waveguide grating (AWG)
multiplexers (MUX) and de-multiplexers (DMUX).
First, data rate per channel increases from today’s non-interoperable
100Gbps direct-detect transceivers to 400Gbps interoperable coherent400ZR modules. Second, the current DWDM
infrastructure can be increased from 32 channels of 100 GHz-spaced DWDM signals
to 64 channels of 75 GHz-spaced DWDM signals. The total DCI fiber capacity can thus
be increased from 3.2 Tb/s (100Gb/s/ch. x 40 ch.) to 25.6 Tb/s (400Gb/s/ch. x
64 ch.), which is a total capacity increase of 800 percent.
NeoPhotonics technology overcomes multiple
challenges to transporting 400ZR signals in 75 GHz-spaced DWDM channels. The 400ZR signal
utilizes an approximately 60 Gbaud symbol rate and 16 QAM modulation, resulting
in a broader transmitting signal spectrum compared to that of a standard 100
Gb/s coherent or PAM4signals. Furthermore, it is recognized
that the center frequencies of the lasers, MUX and DMUX will all drift due to temperature
changes and aging. Consequently, as the channel spacing is reduced from 100GHz
to 75GHz, adjacent channel interference (ACI) becomes more critical, and can
potentially degrade the optical signal-to-noise ratio of 400ZR signals.
The filters used in NeoPhotonics MUX and DMUXunits are designed to limit ACI while at the same time having a stable center
frequency against extreme temperatures and aging. The optical signal spectrum
of the pluggable 400ZR transmitter is very important for two reasons.
First, the spectrum should not be too wide, as that would result in “spillover
energy” impacting its neighbor DWDM channels. Second, it also cannot be
too narrow, as that would degrade the signal quality or even recoverability,
especially after the MUX and DMUX filtering.
NeoPhotonics has demonstrated end-to-end 90km DCI
links using three in-house 400ZR pluggable transceivers with their tunable
laser frequencies tuned to 75GHz spaced channels, and a pair of passive
75GHz-spaced DWDM MUX and DMUX modules designed specifically for this
application. The optical signal-to-noise ratio (OSNR) penalty due to the
presence of the MUX and DMUX and the worst-case frequency drifts of the lasers,
as well as the MUX and DMUX filters, is less than 1dB. The worst-case component
frequency drifts were applied to emulate the operating conditions for aging and
extreme temperatures.
“The combination of compact 400ZR silicon
photonics-based pluggable coherent transceiver modules with specially designed
75 GHz channel spaced multiplexers and de-multiplexers can greatly increase the
bandwidth capacity of optical fibers in a DCI application and consequently
greatly decrease the cost per bit,” said Tim Jenks, Chairman and CEO of
NeoPhotonics. “These 400ZR coherent
techniques pack 400Gbps of data into a 75 GHz wide spectral channel, placing
stringent requirements on the multiplexers and de-multiplexers. We are
uniquely able to meet these requirements because we do both design and fabrication
of planar lightwave circuits and we have 20 years of experience addressing the
most challenging MUX/DMUX applications,” concluded Mr. Jenks.
About NeoPhotonics
