NTS—A nanosatellite space trial Elliott Coleshill à , Jeff Cain, Franz Newland, Ian D’Souza COM DEV Ltd., Cambridge, Ontario, Canada article info Article history: Received 29 January 2009 Received in revised form 2 November 2009 Accepted 8 November 2009 Available online 5 December 2009 Keywords: Nanosatellite AIS Automated information System NTS abstract The COM DEV Mission Development Group has recently launched a nanosatellite mission called NTS (Nanosatellite Tracking of Ships). NTS is a space trial, intended to provide proof-of-concept validation for a COM DEV AIS (Automatic Identification System) radio that has been specifically designed to receive ship AIS transmissions from low Earth orbit. The AIS system uses the very high frequency (VHF) band and provides detailed information about each equipped vessel. Not only does this system provide information such as the location of a vessel, but it also provides heading, engine status and other crucial information about the ship. Designed for terrestrial use, the AIS system traditionally has a range of only 100 km and uses a local self-organized time-division multiple access (SO-TDMA) scheme to ensure transmissions from all ships in any self- organized cell do not overlap. Receiving these signals from a space platform presents an opportunity to provide wide area monitoring of shipping activity. Detection of AIS signals from space will provide a new capability to track and monitor large maritime vessels even when there are large distances from traditional shore based detection systems. The NTS program was designed to be a low cost demonstration satellite and provide rapid risk mitigation to assist in the development of a future constellation of spacecraft that could provide operational AIS from space (AIS-S) reception and dissemination. The scope of the NTS program was kept to a minimum with focus on the design, development and demonstration of a new payload. The nanosatellite bus was developed using a combination of pre-existing designs by the University of Toronto Institute of Aerospace Studies/Space Flight Laboratory (UTIAS/SFL). The resulting bus design was a combination of their CanX-2 and Generic Nanosatellite Bus. The NTS spacecraft is able to provide the capability to detect AIS signals from low earth orbit with multiple, short AIS signal collection cycles over its planned mission lifetime. The paper presents an overview of the NTS spacecraft, mission concept and preliminary results obtained from the flight. & 2009 Elsevier Ltd. All rights reserved. 1. Introduction The Automatic Identification System (AIS) [1] is a ship- to-ship and ship-to-shore system that is used as an aid for collision avoidance and vessel traffic management. An AIS signal is a short message broadcast by a ship at two different VHF frequencies and includes information about the ship, its course, speed, crew and cargo. AIS transmit- ters are mandated for specific classes of vessels and are being voluntarily added by others (including search and rescue boats and aircraft). Class A is a mandatory service for all ships of 300 gross tonnage and upwards engaged on international voyages, cargo ships of 500 gross tonnage and upwards not engaged on international voyages and passenger ships irrespective of size. Class B is a voluntary Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/actaastro Acta Astronautica ARTICLE IN PRESS 0094-5765/$ - see front matter & 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.actaastro.2009.11.007 à Corresponding author. E-mail addresses: elliott.coleshill@comdev.ca (E. Coleshill), jeff.cain@comdev.ca (J. Cain), franz.newland@comdev.ca (F. Newland), ian.dsouza@comdev.ca (I. D’Souza). Acta Astronautica 66 (2010) 1475–1480