OGS-OFL - Optical Ground Station for Tbit Feeder Link

Objectives

The main objectives of the OGS-OFL activity are

  • to define a preferred concept of the optical feeder link system that matches the features and needs of optical payloads in GEO HTS
  • to identify critical optical technologies that require de-risking
  • to perform selected risk mitigation activities on the constituents of such system with emphasis on the optical ground station 

The activity incorporates a simulation tool and a lab demonstrator for transmission through the atmospheric channel. The simulation tool provides the following features:

  • Use of published models of atmospheric turbulence strength
  • Supports Downlink calculation: temporal behavior & statistics of irradiance
    • at the OGS entrance pupil
    • and in the OGS focal plane / single-mode receiver
  • Supports Uplink calculation: temporal behavior & statistics of irradiance
    • at the target satellite
    • taking into account adaptive pre-compensation & anisoplanatism (point-ahead)
  • Allows for sizing of the downlink / uplink aperture
    • Dimensioning  of the bi-directional AO system
  • Includes effects of wind speed

The Lab Demonstrator provides the following key features:

  • Simulates atmospheric turbulence, using rotating phase screens
  • Validates simulation tool w.r.t. beam propagation effects
  • Can be used as a "plug-in" atmospheric channel simulator
    • at the target satellite, taking into account adaptive pre-compensation & anisoplanatism (point-ahead)
    • at the ground receiver
    • investigate & demonstrate end-to-end performance of an optical communications system including atmospheric channel impact

transparent to communications system (Tx/Rx fiber interfaces)

 

Challenges

This project complements findings of various optical feederlink investigations, such as ESA projects ORELIA and ONUBLA, as well as the BATS project under EU FP7. The challenge is to establish a preferred concept for an optical feeder link system of 1Tbis/s and more:

  • Constitute customer requirements and carry out system analysis
  • Trade-off optical modulation / demodulation schemes, incl. multiplexing / de-multiplexing, optical amplification, and atmospheric turbulence mitigation
  • The high-power handling capability of a large actuator deformable mirror is investigated
  • The activity scope considers an optical bi-directional point-to-point Space-Ground-Links to GEO, while staying compatible to Tbit/s OFL performance requirements
  • In addition, high-power handling capability of a large actuator deformable mirror is investigated.

Benefits

The purpose of the proposed activity is to support the development of the Adaptive Optical Ground Station (AOGS) product series of Synopta, both, stationary or transportable, towards application in Optical Feeder Links (OFL). This type of optical ground station is capable of handling multi-100Gbit/s data rates

Features

The purpose of the proposed activity is to support the development of the Adaptive Optical Ground Station (AOGS) product series of Synopta, both, stationary or transportable, towards application in Optical Feeder Links (OFL). This type of optical ground station is capable of handling multi-100Gbit/s data rates.

System Architecture

The functional test system to be developed in this project is an End-to-End OFL Lab Demonstrator, comprising

  • Optical transmitter and receiver
  • RF modems for validation of user signals
  • Adaptive Optics
  • Atmospheric Channel Simulator

Plan

The work plan comprises three milestones (PDR, TRR, FR) which separate an initial analytical part from a functional test campaign. The work is split into three main parts and is expected to be completed by Q4 2018:

  1. Requirements and System Analysis (KO to PDR)
  2. B/B Manufacturing & Test Preparations (PDR to TRR)
  3. Lab Demonstrators, Test Campaign, Appraisal (TRR to FR)

Current status

The project achieved PDR in January 2018.

Work in progress

Contacts

ESA Contacts

Status date

Monday, January 22, 2018 - 10:19