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A Novel Multiband Spectrum Sensing Method Based on Wavelets and the Higuchi Fractal Dimension
Yanqueleth Molina-Tenorio1, Alfonso Prieto-Guerrero2, Rafael Aguilar-Gonzalez3
1Master of Sciences and Information Technologies, Metropolitan Autonomous University Iztapalapa, Mexico City 09360, Mexico. yanqueleth@xanum.uam.mx.
Sensors (Basel, Switzerland)
|March 20, 2019
Summary
Two new methods for multiband spectrum sensing in cognitive radios were developed. These techniques effectively detect primary user activity, achieving 95% and 98% accuracy in simulations, enhancing spectrum efficiency.
Area of Science:
- Electrical Engineering
- Signal Processing
- Wireless Communications
Background:
- Cognitive radios require efficient multiband spectrum sensing to identify available frequency bands.
- Detecting primary user activity is crucial for dynamic spectrum access and avoiding interference.
Purpose of the Study:
- To implement and evaluate two novel methodologies for multiband spectrum sensing.
- To assess the effectiveness of continuous wavelet transform (CWT) and multiresolution analysis (MRA) for detecting spectrum holes.
- To combine MRA with Higuchi fractal dimension for robust primary user detection.
Main Methods:
- Implementation of continuous wavelet transform (CWT) for edge detection of available spectrum holes.
- Application of multiresolution analysis (MRA) for spectrum hole edge detection.
- Integration of MRA with Higuchi fractal dimension for decision-making on primary user presence.
Main Results:
- Both implemented methods demonstrated good performance on simulated and real signals.
- The first methodology (CWT-based) achieved 95% effectiveness in detecting primary user activity.
- The second methodology (MRA combined with Higuchi fractal dimension) showed 98% effectiveness under simulated conditions with SNR > 0 dB.
Conclusions:
- The CWT and MRA-based methods are effective for multiband spectrum sensing in cognitive radios.
- These techniques provide reliable detection of primary user activity across the wideband spectrum.
- The enhanced performance of the MRA-Higuchi fractal dimension method offers a promising solution for dynamic spectrum access.
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