Database driven dynamic spectrum sharing is one of the most promising dynamic spectrum access (DSA) solution to address the spectrum scarcity issue. In such a database driven DSA system, the centralized spectrum management infrastructure, called spectrum access system (SAS), makes its spectrum allocation decisions to secondary users (SUs) according to sensitive operational data of incumbent users (IUs). Since both SAS and SUs are not necessarily fully trusted, privacy protection against untrusted SAS and SUs become critical for IUs that have high operational privacy requirements. To address this problem, many IU privacy preserving solutions emerge recently. However, there is a lack of understanding and comparison of capability in protecting IU operational privacy under these existing approaches. In this paper, thus, we fill in the void by providing a comparative study that investigates existing solutions and explores several existing metrics to evaluate the strength of privacy protection. Moreover, we propose two general metrics to evaluate privacy preserving level and evaluate existing works with them. 
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                            Spectrum Sharing Dynamic Protection Area Neighborhoods for Radio Astronomy
                        
                    
    
            To enforce incumbent protection through a spectrum access system (SAS) or future centralized shared spectrum system, dynamic protection area (DPA) neighborhood distances are employed. These distances are distance radii, in which citizen broadband radio service devices (CBSDs) are considered as potential interferers for the incumbent spectrum users. The goal of this paper is to create an algorithm to define DPA neighborhood distances for radio astronomy (RA) facilities with the intent to incorporate those distances into existing SASs and to adopt for future frameworks to increase national spectrum sharing. This paper first describes an algorithm to calculate sufficient neighborhood distances. Verifying this algorithm by recalculating previously calculated and currently used neighborhood distances for existing DPAs then proves its viability for extension to radio astronomy facilities. Applying the algorithm to the Hat Creek Radio Observatory (HCRO) with customized parameters results in distance recommendations, 112 kilometers for category A (devices with 30 dBm/10 MHz max EIRP) and 144 kilometers for category B (devices with 47 dBm/10MHz max EIRP), for HCRO’s inclusion into a SAS and shows that the algorithm can be applied to RA facilities in general. Calculating these distances identifies currently used but likely out-of-date metrics and assumptions that should be revisited for the benefit of spectrum sharing. 
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                            - PAR ID:
- 10519021
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-9122-8
- Page Range / eLocation ID:
- 1 to 6
- Subject(s) / Keyword(s):
- Spectrum sharing, citizens broadband radio service devices, dynamic protection area, radio astronomy
- Format(s):
- Medium: X
- Location:
- Glasgow, United Kingdom
- Sponsoring Org:
- National Science Foundation
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