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DVB-T Channels Measurements for the Deployment of Outdoor REM Databases

Kliks A., Kryszkiewicz P., Cichoń K., Umbert A., Perez-Romero J., Casadevall F.

Journal of Telecommunications and Information Technology

2014

nr 3

42--52

In this paper the analysis of the spectrum occupancy in the TV band is provided based on the outdoor measurements campaigns carried out in Poznań, Poland in 2013 and 2014. The goal of this work is to discuss the stability and other important features of the observed spectrum occupancy in the context of outdoor Radio Environment Maps database deployment. Reliable deployment of these databases seems to be one of the critical points in practical utilization of the TV White Spaces for cognitive purposes inside buildings and in densely populated cities. The results obtained for outdoor scenario are briefly compared with the previous measurements conducted indoors in Barcelona, Spain, and in Poznań, Poland.

Spectrum Occupancy in Realistic Scenarios and Duty Cycle Model for Cognitive Radio

López-Benítez M., Casadevall F.

Advances in Electronics and Telecommunications

2010

Vol. 1, no. 1

26--34

Most of the spectrum occupancy measurement campaigns performed to the date in the context of cognitive radio are based on measurements in outdoor high points such as building roofs, balconies and towers. Although these measurement scenarios enable a more accurate estimation of the primary transmitters’ spectral activity, they may not be representative of the spectrum occupancy perceived by a cognitive radio user in many other interesting practical situations where users are not placed in a static high point. In this context, this work presents the results obtained in a spectrum measurement campaign performed over a rich diversity of measurement scenarios of practical interest. The considered scenarios include not only high points but also indoor environments as well as outdoor locations at the ground level in open areas and between buildings. The ariety of considered measurement scenarios provides a broader view and understanding of dynamic spectrum occupancy under different practical scenarios of interest. The impact of considering various locations on the spectral activity perceived by a cognitive radio user is determined, analyzed and quantified. Moreover, a theoretical model for the occupancy levels observed at different locations is developed and verified with the obtained results.