Description
Objective: Development of a miniature spaceflight compatible atomic clock for secure telecommunications.
Targeted improvements: Introduction of Miniature Space Frequency Reference technology. Providing radiation insensitivity and improved stability (target ~10-12 per day) with respect to OCXOs.
Description:
For optimum performance, secure telecommunication applications require very precise time synchronisation between the receiver and the transmitter. For techniques such as FHSS (Frequency Hopping Spread Spectrum), the synchronisation requirement is approximately a few microseconds in order to implement a fast tracking and anti-jamming scheme without penalising the transmission rate. Such accuracies can be maintained for several hours only with atomic clocks.
In comparison to oscillators employing a piezoelectric resonator, atomic clocks offer the additional benefit of being intrinsically insensitive to radiation effects (both ionizing and non-ionizing). Telecom systems like MILSTAR (and its evolution AEHF) embark Rubidium atomic clocks.
Rubidium compact clocks are available in the worldwide commercial market for non-space applications. Performances are in line with the requirements for secure telecommunications, which are less demanding than those for navigation applications. This makes it possible to achieve a compact design with reduced power consumption. Physical package (i.e. atomic resonator) reliability is well proven, but the thermal, mechanical and electronic designs need to be adapted for space application,.
Starting from an existing European design with proven atomic resonator reliability, the overall thermo-mechanical design shall be revised with the objective of power consumption optimisation with a mass target of a few hundred grams. In parallel, the electronics shall be modified to be suitable for space application. The final objective is a fully verified engineering model, including performance verification in a thermal-vacuum environment.