In an ambitious endeavor to revolutionize satellite communications, Phlux Technology, Airbus Defence and Space, and The University of Sheffield have embarked on a trailblazing project funded by the European Space Agency. With a substantial investment of €500,000, the triumvirate aims to develop cutting-edge free space optical communications satellite terminals that will redefine the landscape of space-based communications.
At the heart of this groundbreaking project lie Phlux Noiseless InGaAs™ avalanche photodiodes, which serve as the infrared sensors in FSOC receivers. These innovative APDs are expected to deliver an unprecedented 6 dBm higher sensitivity compared to traditional InGaAs APDs operating at 1550 nm. This remarkable advancement enables the detection of significantly lower signal levels, paving the way for faster, higher bandwidth links with minimal latency. Moreover, the enhanced sensitivity ensures that adequate performance can be maintained for extended periods, as the link integrity is preserved over a wider angle during the satellite's overhead passage.
One of the primary technical hurdles in realizing FSOC lies in the diffraction of infrared signals as they traverse the troposphere, the atmospheric layer closest to Earth. Fluctuations in air temperature, humidity, and turbulence within the atmosphere cause variations in the intensity and angle of incidence of the infrared signal. Consequently, the beam wanders over the signal detector area, limiting performance. To address this challenge, the project focuses on developing a large area, high sensitivity APD that will serve as a wider receptor, mitigating the effects of beam wandering.
The radiation-hard detector module being developed as part of this project holds immense potential for various applications beyond FSOC. It could be utilized in space debris monitoring, greenhouse gas detection, and space navigation, showcasing the far-reaching impact of this innovative technology.
Ben White, CEO of Phlux Technology, expressed his enthusiasm for the project, stating, "This project is an endorsement of the value of our patented APD technology developed at The University of Sheffield. With more than an order-of-magnitude improvement in sensitivity over traditional devices, we offer the enabling component that makes other technology breakthroughs possible. Higher performance FSOC links are a perfect example, and it's exciting to be working with such prestigious organizations as ESA and Airbus Defence and Space."
Ludovic Blarre, leading Airbus Space Systems optical communication roadmap, highlighted the potential impact of the project, saying, "The availability of APD products at 1550 nm for optical communication with sensitivities close to those of fibered low noise optical amplifiers could be a game changer for the development of cost-effective laser terminals and optical ground stations. This will be an enabler for the rapid development of optical communication in satellites for direct-to-earth applications and inter-satellite links with data rates below 10Gbps. Our team is delighted to work with Phlux Technology and the University of Sheffield towards this goal and to carry out irradiation tests on their patented APD technology."
Professor Chee Hing Tan from the University of Sheffield expressed his enthusiasm for the project, stating, "This is a very challenging and exciting project that will provide opportunities for our team to extend our patented technology to an exciting new application in FSOC. Working with ESA, we hope to provide a disruptive technology that will accelerate the adoption of satellite to ground FSOC."
As the demand for bandwidth continues to surge beyond the capabilities of radio frequency systems, the FSOC market is poised for exponential growth. According to Allied Market Research, the market is expected to reach a staggering $4.8 billion by 2031, with a compound annual growth rate of 31.3%. The first phase of this groundbreaking project is set to conclude by the end of September 2025, marking a significant milestone in the advancement of satellite communications technology.