Time and frequency transfer with a microwave link in the ACES/PHARAO mission

TL;DR

This paper discusses the development of a microwave link system for precise time and frequency transfer in the ACES/PHARAO space mission, emphasizing software modeling and real-time data processing for high accuracy.

Contribution

It presents the theoretical modeling, numerical simulations, and software development efforts for accurate time and frequency transfer via microwave links in space.

Findings

Phase accuracy and stability are crucial for mission success.

Software prototype development is underway to achieve real-time high-precision measurements.

Key aspects of measurement and software status are discussed.

Abstract

The Atomic Clocks Ensemble in Space (ACES/PHARAO mission), which will be installed on board the International Space Station (ISS), uses a dedicated two-way Micro-Wave Link (MWL) in order to compare the timescale generated on board with those provided by many ground stations disseminated on the Earth. Phase accuracy and stability of this long range link will have a key role in the success of the ACES/PHARAO experiment. SYRTE laboratory is heavily involved in the design and development of the data processing software : from theoretical modelling and numerical simulations to the development of a software prototype. Our team is working on a wide range of problems that need to be solved in order to achieve high accuracy in (almost) real time. In this article we present some key aspects of the measurement, as well as current status of the software's development.