Abstract

This study focuses on improving the functioning of multiband Orthogonal Frequency Division Multiplexing (OFDM) system by utilizing wavelet transform as a substitute to Fast Fourier Transform (FFT). The performance is further refined by apt inclusion of modulation technique. Error control codes are utilized which aims at the removal of error from the transmitted bits. In addition to attain diversity Alamouti code is concatenated with error control codes. OFDM is the best fit for cognitive radio and sensing the free holes is the key task of any cognitive system. This study additionally also analyses the performance of energy detection based spectrum sensing in the presence of various noise models.

Keywords:

Alamouti code, cognitive radio, energy detection, error control codes, noise models, wavelet transform,

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Competing interests

The authors have no competing interests.

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