Received signal interpolation for context discovery in cognitive radio

This paper addresses the context acquisition to characterize different features of a primary network based on the power measurements obtained by a sensor network. In particular, it presents a comparative study of the impact of natural neighbor, linear, and nearest neighbor interpolation techniques carried out over the measurements at different geographical positions. Extracted features include transmitter position, antenna pattern or propagation model. An evaluation is carried out in scenarios including the effect of both correlated and non-correlated shadowing.Peer ReviewedPostprint (author’s final draft

Cognitive pilot channel enabling spectrum awareness

This paper presents the Cognitive Pilot Channel (CPC) solution as a mechanism allowing the terminal to be aware of the communication means available at a given time and place in a flexible spectrum management scenario. The different aspects to be considered in the CPC deployment are highlighted, together with the different implementation options. As a result, a CPC dimensioning methodology is formulated, identifying the main parameters involved in the process and the corresponding design trade-offs.Postprint (published version

On the applicability of image processing techniques in the radio environment characterisation

This paper presents a novel framework based on image processing techniques for the radio environment characterisation. Specifically, after digitalising a given scenario in accordance with the frequencies that are detected in each point, an image can be built whose pixel intensities capture the radio-electrical conditions. Through non-linear filtering and object detection operations the proposed framework allows identifying the homogeneous regions where certain frequencies can be detected. This methodology can be used in different contexts, such as the construction of databases to provide the terminals with spectrum awareness in flexible spectrum scenarios to facilitate the switch-on procedure or the secondary usage of spectrum, the support to devise proper strategies for cell and RAT selection, etc