News: Optoelectronics
7 March 2022
NeoPhotonics launches ultra-narrow-linewidth laser for LEO satellites
NeoPhotonics Corp of San Jose, CA, USA – a vertically integrated designer and manufacturer of silicon photonics and hybrid photonic integrated circuit (PIC)-based lasers, modules and subsystems for high-speed communications – has launched a radiation-tolerant version of its Nano ultra-pure-light tunable laser, for use in low-earth-orbit (LEO) satellite communications applications.
NeoPhotonics’ existing Nano-ITLA (integrated tunable laser assembly) is in high-volume production for terrestrial fiber-optics applications and is used by many of the leading optical networking companies in their most advanced coherent pluggable modules and high-speed embedded systems. The new radiation-tolerant laser introduces enhancements including an adaptive approach to achieve extended-lifetime operation of the proven Nano laser hardware in a radiation flux environment to enable reliable operation in space without compromise to performance and stability.
Multiple companies are now deploying or developing constellations of low-earth-orbit satellites to bring high-bandwidth communications to areas not currently served by wireless infrastructure. These constellations consist of thousands of satellites which must have high-bandwidth connections between them to avoid service drop-outs. These satellite-to-satellite communications links are now shifting from microwave to coherent optical technology, taking advantage of the vast increase in transmission capacity developed for terrestrial fiber-optic communications, where 800Gbps is now regularly transmitted on a single wavelength.
While coherent communications technology is now highly advanced, space is a hostile environment for the electronics and related hardware used in telecommunications, largely due to radiation impacts from galactic cosmic rays, high-energy particles from the sun, and particles trapped by the earth’s magnetic field. Special ‘radiation hardened’ electronic devices, which are more robust than those typically used on the ground, are often used to mitigate these issues, but they can add significantly to cost. For the lasers used in coherent communication, the control electronics are often more vulnerable to these radiation effects than the laser itself.
One example of the laser control subsystem electronics that is particularly vulnerable to ionizing radiation is the memory (RAM and FLASH) that microprocessors rely on. While radiation effects on memory can be lessened by using special packaging or by more expensive hardware components, the effects of ionizing radiation on memory corruption can also be mitigated by incorporating radiation-tolerant software enhancements, resulting in greatly improved reliability, recovery and resilience, as has been demonstrated during laboratory testing designed to simulate low-earth-orbit conditions.
“NeoPhotonics has been a leader in the design, development and high-volume production of ultra-narrow-linewidth tunable lasers for coherent communications over the last decade, and we are excited to offer our high-performance to the exciting new application of satellite communications,” says chairman & CEO Tim Jenks. “We have used our long experience and deep understanding of lasers technology to develop an innovative software-centric approach to radiation tolerance that speeds time to market, while maintaining performance and limiting costs.”
