The demand for wireless spectrum access has increased dramatically over the last years. At the same time, field measurements have shown that the licensed spectrum is highly underutilized. This way, dynamic spectrum access employing cognitive radio concept attracted lots of research efforts within academic and industrial bodies. Cognitive radio is a location-aware radio which acquires temporal awareness about the incumbent user activities within the wireless spectrum, and subsequently gains secondary spectrum access, if a specific frequency band is deemed to be available. Lots of research efforts have been done on spectrum awareness techniques which lead to efficient tools achieving accurate results. However, most of this research is done at the individual cognitive radio level. In order to fully enjoy the dynamic spectrum opportunities as well as optimizing the overall spectral efficiency of the available spectrum, network level spectrum awareness is required. Further, network level spectrum monitoring can be used for monitoring the network performance indicators such as quality of service (QoS), and further for interference detection and mitigation. In this project, we employ a combination of ground based sensors, distributed over a vast geographical area, and on-board satellite sensors, which are connected through in-orbit GEO satellites to a data centre, in order to collect temporal observations over a wide range of frequencies and geographical locations. The data centre then applies advanced signal processing algorithms including centralized spectrum cartography techniques to produce a global spectrum map over three dimensions: time, frequency, and location. This map is used by the network manager which can be the data centre itself, to optimize the network availability and throughput by providing service to the cognitive users. To achieve this goal, in this project, first we determine the satellite sensor network architectures which are appropriate for the objectives of this project, and then we develop cooperative signal processing algorithms required to produce the spectrum map based on ground sensors, followed by developing the required algorithms to perform on-board spectrum monitoring, and interference detection. The information obtained from on-board and ground sensors are finally combined in the data centre to obtain accurate information about all both terrestrial and satellite terminals. In order to develop the required algorithms in this project, we shall exploit advanced signal processing tools, e.g. estimation theory, beamforming, and distributed signal processing.