Overview of the Laser Communication System for the NICT Optical Ground Station and Laser Communication Experiments on Ground-to-Satellite Links

摘要

The National Institute of Information and Communications Technology (NICT) conducts research and development of laser communication technologies necessary for the realization and quality improvement of optical space communications. An in-orbit verification experiment of the inter-orbit optical communication link between the Optical Inter-orbit Communications Engineering Test Satellite (OICETS) (known as "Kirari"), which was developed by the Japan Aerospace Exploration Agency (JAXA), and the Advanced Relay Technology Mission Satellite (ARTEMIS), developed by the European Space Agency (ESA), was successfully conducted in December 2005. Kirari was launched by a Dnepr Launch Vehicle from the Baikonur Cosmodrome in the Republic of Kazakhstan and injected into Low Earth Orbit (LEO) at an altitude of 610 km and an inclination of 97.8°. The functionality of the satellite systems was checked during the first three months, in which acquisition and tracking of stars and planets was successfully performed. In December 2005, the first bidirectional laser communication link between Kirari and ARTEMIS was successfully established. The Kirari optical communication demonstration experiment with the NICT optical ground station (KODEN) was successfully realized because the optical antenna can be pointed toward the optical ground station with a special satellite attitude control system. The objectives of KODEN were to confirm the tracking abilities of Kirari and the optical ground station in the presence of atmospheric turbulence, as well as to verify the capabilities of laser communication systems with respect to ground-to-LEO satellite links. Phases 1, 2, and 3 of the bidirectional ground-to-satellite laser communication experiment were successfully performed in March, May, and September 2006, and Phase 4 of the experiment was conducted between October 2008 and February 2009 under research collaboration with JAXA. In this paper, the results obtained in Phases 1-4 of the KODEN experiment are summarized.