Fremont,
CA, March 15, 2005 -
Optoplex today announced the introduction of its newest
product, the DPSK.
The DPSK is designed to be the industry’s smallest,
athermal differential phase-shift keying demodulator.
The DPSK converts Phase modulation into Amplitude modulation
over the entire C+L band without requiring unwieldy monitoring
and temperature feedback controls to lock the frequency.
In
comparison to the established on-off keying (OOK) modulation
format, DPSK is emerging as the preferred modulation format
for transmitting 40-Gb/s signals because DPSK exhibits
less power penalties and therefore allows for farther
transmission ranges.
The
crux of the DPSK system is its demodulator. Prevailing
DPSK demodulator technology is based on a Mach-Zehnder
interferometer. The glaring drawback to the Mach-Zehnder
interferometer is its fiber-based construction, making
it inherently temperature sensitive and therefore requiring
additional monitoring circuitry and feedback loops to
maintain a proper operating temperature.
In
contrast, Optoplex’s DPSK demodulator is based on
a free-space optical design, allowing it to be compact,
athermal and polarization-independent. The measured frequency
drift of Optoplex’s device over temperature is only
~0.02 GHz/°C. Further, the DPSK exhibits a total polarization-dependent
frequency shift of less than 0.3 GHz over the 0~70°C
temperature range with an extinction ratio of greater
than 30 dB. Each DPSK will cover all channels in the C+L
band.
The
DPSK measures only 25 mm x 25 mm x 10 mm because it does
not require any sophisticated monitoring and feedback
controls to lock a desired frequency. Having passed rigorous
reliability testing based on Telcordia GR-1221 requirements,
the DPSK is production-ready for mass implementation.
With
the DPSK, Optoplex Corporation once again demonstrates
its capacity to introduce revolutionary new components
to solve today’s most challenging optical communication
problems.
