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In dynamic spectrum access (DSA), Environmental Sensing Capability (ESC) systems are implemented to detect the incumbent users' (IU) activities for protecting them from secondary users' (SU) interference as well as maximizing secondary spectrum usage. However, IU location information is often highly sensitive and hence it is preferable to hide its true location under the detection of ESCs. In this paper, we design novel schemes to preserve both static and moving IU's location information by adjusting IU's radiation pattern and transmit power. We first formulate IU privacy protection problem for static IU. Due to the intractable nature of this problem, we propose a heuristic approach based on sampling. We also formulate the privacy protection problem for moving IUs, in which two cases are analyzed: (1) protect IU's moving traces; (2) protect its real-time current location information. Our analysis provides insightful advice for IU to preserve its location privacy against ESCs. Simulation results show that our approach provides great protection for IU's location privacy. 

Spectrum monitoring is a powerful tool in dynamic spectrum access to help secondary users access the unused spectrum white space. The common approach for spectrum monitoring is to build infrastructures (e.g. spectrum observatories), which cost much money and manpower but have relatively low coverage. To aid in this, we propose a crowdsourcing based spectrum monitoring system for a large geographical area that leverages the power of masses of portable mobile devices. The system can accurately predict future spectrum utilization and intelligently schedule the spectrum monitoring tasks among mobile secondary users accordingly, so that the energy of mobile devices can be saved and more spectrum activities can be monitored. We also demonstrate our system's ability to capture not only the existing spectrum access patterns but also the unknown patterns where no historical spectrum information exist. The experiment shows that our spectrum monitoring system can obtain a high spectrum monitoring coverage and low energy consumption.