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The NorSat-3 mission, with expected launch Q2/Q3 2020, aims to enhance the Norwegian recognized maritime picture with an experimental ship navigational radar detector (NRD) in addition to an AIS receiver. The NRD aims to geolocate ship navigation radars within 10 km circular error probable and verify AIS positions. The 10º NRD antenna field of view will nominally be pointed towards the horizon in order to maximize the area coverage and view of the ships’ navigation radar main lobe. Operating in a near polar low earth orbit the Norwegian area of interest may be covered between 10 and 15 times per day if pointing the antenna suitably. Achieving the desired geolocation accuracy and area coverage, while minimizing polarization loss, requires a highly capable attitude determination and control system. The signal processing capabilities of the Zynq Ultrascale+ system-on-chip enables the radar signal processing in orbit, although also requiring a large platform power generation capability. The mission, payloads and platform are described in this paper, including some of the lessons learned. All flight subsystems and payloads have completed their relevant unit environmental tests, including proton irradiation of NRD electronics. Final system verification and environmental testing begins August 2019, with a target flight readiness review November 2019.

AISSat-1 was launched on July 12, 2010 and is believed to be the first high performance nano-satellite to provide an observational service to governmental authorities. The primary mission objective is to perform maritime observation in the Norwegian High North and High South, thereby making a considerable contribution to the maritime situational awareness (MSA) of these areas. The satellite is built, tested and prepared for flight by the Space Flight Laboratory at the University of Toronto Institute for Aerospace Studies (UTIAS/SFL), and is based on the 20 cm cube Generic Nano-satellite Bus (GNB). UTIAS/SFL also handled the launch of AISSat-1 by an Indian Polar Satellite Launch Vehicle (PSLV) from southern India. The payload is an AIS receiver developed and manufactured by Kongsberg Seatex AS, Trondheim Norway. The Norwegian Defence Research Establishment (FFI), Kjeller Norway developed the AISSat-1 mission concept and has been responsible for managing the project and for testing and preparing the AIS payload for flight. The Automatic Identification System (AIS) for maritime vessels was introduced by the International Maritime Organization (IMO) to enhance the safety of life at sea (SOLAS). Vessels greater than 300 gt or carrying 12 or more passengers are broadcasting AIS messages on two channels in the maritime VHF band on regular basis to neighboring vessels for collision avoidance, and also to shore stations for vessel traffic services (VTS). AISSat-1 is designed to receive these AIS messages in space, and to forward the messages to the Norwegian Coastal Administration (NCA), with the aim to extend the range of the Norwegian ground based AIS network to also cover ocean areas at the high seas. Some early results from AISSat-1 presented here clearly demonstrate that a low cost high performance nano-satellite can provide excellent and much needed maritime observation information to government authorities.

The linear FMCW radar has become more popular in recent years mainly due toadvances in digital signal processing and the good performance of the radar at closeranges. What puts limits to the performance is mainly phase noise. Because trans-mission and reception happen simultaneously, the phase noise will limit the maxi-mum power that should be used and hence also the ability to detect weak targets.By ensuring during the design process that the phase noise is low, the radar s perfor-mance will thus get better. This thesis describes the construction of a FMCW radarfrequency synthesizer where the focus is mainly on phase noise. The functionalityof the circuit is shown to be successful, but there is more phase noise than what ispredicted. Several causes for this are discussed. Important background theory aboutradars, phase noise and phase-locked loops is presented and several simulations areperformed in order to get a better understanding. The conclusion of the work isthat it is not very hard to build a synthesizer, but in order to tweak the phase noiseperformance to be as good as the linear theory tells it to be, careful attention mustbe paid during all stages of the design.