The COM DEV Missions group is dedicated to providing mission solutions on a global scale for a range of applications including safety, security, environmental monitoring and protection; with a specific focus on communications and scientific applications.
We conduct feasibility studies, mission simulations and end-to-end analyses to determine if a cost effective space-based solution can be provided. Armed with this information, the customer can determine if a microspace solution provides the best capability, performance and flexibility for the intended application. To date, our group has worked on microsateliite solutions for a range of domestic and international needs. In parallel, the group is actively engaged in small and microsatellite mission technology development contracts with the Canadian Space Agency and the Canadian Department of National Defence. Our strong understanding of standard space processes (whether it be quality, design or manufacturing) allows us to intelligently adapt and ensure that we are able to plan and execute activities in a highly streamlined manner. This results in lower cost and shorter schedules than standard space program while maintaining high quality. The core team is supported by dedicated facilities for mission, spacecraft and payload simulation, conceptual and detailed design and prototyping, as well as build, integration and test. This includes:
The Maritime Monitoring and Messaging Microsatellite, M3MSat, is the first implementation of the COM DEV Advanced Integrated Microsatellite (AIM) satellite bus, and the first complete satellite to be designed and built in-house at COM DEV International. M3MSat was developed for the Canadian government, specifically Defence Research and Development Canada (DRDC) and the Canadian Space Agency (CSA), and for COM DEV’s sister company, exactEarth Ltd., to expand their AIS monitoring constellation. The microsatellite will be launched into a high inclination, low earth orbit (~500km) on a PSLV rocket by the Indian Space Research Organisation in 2016. The primary payload will record two channel dual polarization AIS data which will be processed on the ground to extract the AIS messages. Although AIS data collection is the primary objective of this mission, it also carries a Low Data Rate (LDR) UHF communications terminal and a Deep-Dielectric Charging Monitor (DDCM) from DPL Science. The LDR will demonstrate two-way, low data rate communication between itself and a dedicated ground terminal. The DDCM (provided by DPL and sponsored by the CSA) is dedicated to measuring material and spacecraft charging. The satellite life span is expected to be at least five years.
Photo below: Working on M3MSAT at the CSA David Florida Laboratories in Ottawa.
The Automatic Identification System, or AIS, is designed for ship-to-ship and ship-to-shore communication to aid in collision avoidance and vessel traffic management. The use of AIS is mandated by the International Maritime Organization aboard ships of more than 300 gross tons and aboard all passenger ships. AIS messages include ship identification information in addition to position, course and speed. The messages are broadcast at 162 MHz with a horizontal range of approximately 20 nautical miles, or 40 km. The system uses a SOTDMA (self-organized time division multiple access) access scheme which prevents messages from ships within communication range from overlapping. In 2008, COM DEV launched a nanosatellite called NTS and proved that AIS messages could also be collected from space. This meant that it is possible to develop a global picture of ship traffic … something that is not available if one was to just use ground based systems. However, the SOTDMA system does cause some difficulty when receiving AIS signals from space. Ships within view of each other form self-organized “cells”. While some coordination between cells does occur, a ship at an extreme end of one cell is not coordinated with a ship at the other end of a different cell. The result is that ships not directly connected can, and will, send their messages at the same time. This causes message overlaps and, since a satellite can “see” several hundred independent cells, space-based AIS must use innovative ways to separate the individual messages. The fact that the ships send out their messages fairly regularly means that even with the occasional missed message, a comprehensive view of the maritime environment can be built up.
The NTS nanosatellite was launched in 2008 with the goal of demonstrating the reception of AIS signals from space. The satellite was built in partnership with the University of Toronto Institute of Aerospace Studies / Space Flight Laboratory (SFL) and was a prime example of responsive space with a project kick-off in Sept 2007 and launch in April 2008. The satellite is based on the SFL generic nanosatellite bus platform and a COM DEV developed AIS receiver. As a technology demonstration, the satellite and mission needed to survive a minimum of 1 month in order to demonstrate its objectives; however, it was hoped that the mission would last as long as 6 months to characterise the RF environment. The mission easily met its requirements and became an operational part of the fledgling exactEarth constellation. NTS was even used operationally to provide data for the World Cup in South Africa and the Olympic Games in Vancouver, Canada. As of April 2015, the satellite is no longer part of the operational AIS constellation of satellites but is still used as an experimental platform to test out the latest innovations in space-based AIS detection.
Following on from the success of the NTS mission, M3MSat was developed to be an operational satellite based on the 60x60x80cm AIM microsatellite platform. The platform was developed in collaboration with SFL in order to meet the CSA Multi-Mission Microsatellite Bus requirements for a generic Canadian bus and to provide a flexible platform for current and future operational missions. It has a modular design which allows the payload to be integrated separately and then installed on the bus late in the assembly process. The payload bay is situated on one of the largest spacecraft faces, maximizing the area available for antennas.
Photo below: The integrated M3MSAT satellite prior to mounting the solar panels. The AIM bus systems are contained in the black L-shaped section, while the payload is exposed in the upper left portion.
The platform provides the power, communication, attitude control, and data handling systems to support the payload operation. Thermal control is passive, with the exception of battery heaters. Solar panels and a lithium battery provide approximately 150W peak power, and 80W average, though this depends on the orbit. S-Band communication provides a 4kbps uplink and a 2Mbps downlink, which, for M3MSat, serves as the TT&C link as well a back-up link for payload data. The attitude control system consists of sun sensors, rate sensors, magnetometers, reaction wheels, torquer rods, and a dedicated attitude determination and control computer (ADC). The controller provides three-axis stabilized control with better than 5° pointing accuracy, in either an inertial pointing or a nadir tracking configuration. Data handling is provided by the CAN bus and housekeeping computer (HKC). Commands from ground are placed on the CAN bus by the communication system, and received directly by the intended unit. The HKC provides functionality of time-tagged commanding, housekeeping telemetry collection, and storage of back orbit data. A GPS receiver provides an onboard clock signal, as well as position data which can be used for orbit estimation on ground. The modular design means that performance is scalable to the mission and payload requirements. This ensures that the required performance can be achieved without unnecessary cost or complication.
For M3MSat, the platform has a dual redundant design for reliability which even includes the CAN bus. With the exception of the main mission antennas, only non mission critical equipment is not redundant. S-Band antennas are mounted on two opposing faces to ensure successful communication without attitude control. All six faces of the satellite have solar panels, to ensure power can be generated in all attitudes.
The AIS payload consists of a dual-polarization AIS receiver antenna, followed by redundant receiver and recorder chains. The payload data is downlinked to ground through a dedicated C-band system consisting of redundant C-band transmitters, both connected to a single antenna. Both receivers can be active simultaneously, but the downlink can only be active from one recorder at a time.
Photo below: The M3MSAT earth facing deck. The AIS (VHF), LDR (UHF), and C-Band antennas are mounted to the payload assembly. While the S-band antennas are mounted to the platform corner posts. The DDCM is also shown in this view.
The satellite was assembled from in-house and procured hardware and tested at COM DEV International facilities. UTIAS/SFL built and tested the attitude control system, power distribution system and on-board computers. In addition to being responsible for the mission and satellite systems design, COM DEV focused on the communication system, navigation system, payload and the structure and thermal designs. Functional testing was performed at unit, subsystem, and system levels using the actual ground station equipment to spur the simultaneous development and test of ground tools.
The formal environmental test campaign was performed at the CSA’s David Florida Laboratories and included near field antenna and EMC testing, thermal-vacuum, vibration and shock tests and an extended burn-in. In addition, an End-to-End test using free-space RF communication with the DRDC operation centre was performed. These tests ensure that the satellite will survive launch and perform as expected in orbit and by operating the satellite in the same manner and using the same tools as will be used in operations, the team developed an in depth understanding of how the system behaves and how to react when it doesn’t behave as expected.
Photo below: Ready for testing inside the T-Vac chamber at DFL. Liquid nitrogen in the chamber walls cooled the chamber, while the infrared light sources surrounding the satellite provided heat to simulate the on-orbit environment.
Following launch, COM DEV will participate in a three month commissioning program with the government operations team. At the successful completion of commissioning, operation will be handed to the government, who will work with exactEarth to ensure the maximum benefit is obtained from this asset.
Nanosatellite Tracking Ships: Cost-Effective Responsive Space
Pranajaya F.M., Zee R.E., Cain J., Kolacz R.
Proceedings of the 4S Symposium 2010, Madeira, Portugal. Paper: IAC2010-S16-1
NTS – Nanosatellite Space Trial
Coleshill, E., Cain, J., Newland, F. and DSouza, I.
Acta Astronautica 66 (2010) 1475-1480.
Nanosatellite Tracking of Ships: From Concept to Launch in 7 Months
Pranajaya, F., Zee, R., Cain, J.S. and Kolacz, R.
Proceedings of the 23rd Annual AIAA/USU Conference on Small Satellites, August 10-13, 2009. Paper: SSC09-IV-11. Logan, Utah, US.
Nanosatellite Tracking of Ships – Review of the first year of operations
Newland, F., Coleshill, E., D’Souza, I., and Cain, J.S.
Proceedings of the 7th Responsive Space Conference, Paper AIAA-RS7-2009-6005, Los Angeles, US, April 2009.
Nanosatellite Tracking of Ships: Responsive, Seven-Month Nanosatellite Construction for an On-Orbit Automatic Identification System Experiment
Pranajaya, F., Zee, R., Cain, J.S. and Kolacz, R.
Proceedings of the 7th Responsive Space Conference, Paper AIAA-RS7-2009-3010, Los Angeles, US, April 2009.
Space-Based AIS: Contributing to Global Safety and Security
Cain, J.S. and Meger, E.
Presented at the ISU 13th Annual Symposium – ‘Space for a Safe and Secure World’. Strasbourg, France, 18 – 20 February 2009.
NTS – A Nanosatellite Space Trial
Coleshill, E., Cain, J., Newland, F., D’Souza, I.
Space Based AIS Detection with the Maritime Monitoring and Messaging Microsatellite
Nathan G. Orr, Jeff Cain, Luke Stras, Robert E. Zee
64th International Astronautical Congress, Sept 2013, IAC-13, B4.4.10x18317
A Compact Circularly Polarized Antenna using an Array of Folded-Shorted Patches
S.K. Podilchak, M. Caillet, D. Lee, Y.M.M. Antar, L. Chu, J. Cain, M. Hammar, D. Caldwell, E. Barron
IEEE Transactions on Antennas and Propagation, Vol. 61, No. 9, September 2013
AIM Microsatellite Platform: A Canadian Multi-Mission Satellite Bus Solution
Jeffrey Cain and Franz Newland
30th AIAA International Communications Satellite System Conference (ICSSC), Sept 2012
Space based AIS Detection with the Maritime Monitoring and Messaging Microsatellite
N. Orr, J. Cain, L. Stras and R. Zee
Small Satellite Systems and Services – The 4S Symposium 2012, Portoroz, Slovenia, June 2012.
Compact Antenna for Microsatellite Using Folded Shorted Patches and an Integrated Feeding Network
S.K. Podilchak, M. Caillet, D. Lee, Y.M.M. Antar, L. Chu, P. Cowles, J. Cain, M. Hammar, D. Caldwell, E. Barron.
EuCAP 2012 Conference. 26-30 March, 2012. Pp. 1819 - 1823
Solar Array Arcing Mitigation for Polar Low-Earth Orbit Spacecraft
Bonin, G., Orr, N., Zee, R. and Cain, J.
Presented at the 24th Annual AIAA/USU Conference on Small Satellites, August 9 - 12, 2010. Paper: SSC10-X-7