NeoPhotonics Releases L-Band Coherent Optics Solutions to Double the Capacity of Optical Fibers

Posted Mar 23, 2020 by NeoPhotonics Corporation

Leading developer of silicon photonics and advanced hybrid photonic integrated circuit based lasers, modules and subsystems, NeoPhotonics, has developed an L-Band suite of coherent optical components, including its 64 GBaud L-Band High Bandwidth Coherent Driver Modulator (HB-CDM), 64 GBaud L-Band Intradyne Coherent Receiver (ICR) and Ultra-Narrow Linewidth L-Band Tunable Laser Micro-ITLA. Together with NeoPhotonics standard C-Band coherent components, these new products enable customers to double the capacity of optical fiber links.

The C-Band is the primary band for telecommunications with wavelengths centered around 1550 nm. The L-Band uses wavelengths centered around 1590 nm and is primarily used to complement the C-Band to increase data capacity, especially in long-haul networks. By adding channels in the L-Band, operators can double the capacity of an optical fiber. NeoPhotonics 64 Gbaud coherent components and tunable lasers enable single channel 600G data transmission over short haul data center interconnect (DCI) links using 64 QAM. These components also support 400G over metro distances of 400-600 km using 64 GBaud and 16 QAM or 200G over long-haul distances of greater than 1000 km using 64 GBaud and QPSK.

The NeoPhotonics L-Band External Cavity (ECL) micro-ITLA incorporates the same laser architecture as the C-Band laser for a pure optical signal with an ultra-narrow linewidth and very low phase noise. In coherent systems, any error in the phase of the signal and reference lasers, due to the laser’s linewidth, can cause data errors, thereby making narrow linewidth critical in systems using higher order modulation.

The NeoPhotonics 64 Gbaud L-Band HB-CDM co-packages an Indium Phosphide based Mach-Zehnder (MZ) quadrature modulator chip with a linear, quad-channel, differential 64 GBaud driver. Both the C-Band and L-Band versions of the HB-CDM are designed to be compliant to the Optical Internetworking Forum (OIF) Implementation Agreement OIF-HB-CDM-01.0 “High Bandwidth Coherent Driver Modulator”.

The latest 64 Gbaud L-Band Micro-ICR incorporates an integrated comixer chip and four balanced photodiodes with four differential linear amplifiers to provide four output channels at 64 GBaud. The form factor of the High Bandwidth Coherent Receiver is designed to be compliant with the OIF Implementation Agreement for Micro Integrated Intradyne Coherent Receivers; IA #OIF-DPC-MRX-02.0.

For applications that require more capacity than provided by the standard C-Band, but do not require the full L-Band, each of these components is available in a “C++” version, which supports tuning across the full “Super C-band” covering 6.0 THz of spectrum or up to 50 percent more than standard systems. These C++ components can support 80 channels at 75 GHz channel spacing, which effectively increases the capacity of an optical fiber by as much as 50 percent over standard C-Band only systems at comparable distances.