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Energy-Efficient Fast Fourier Transforms for Cognitive Radio Systems
November/December 2010 (vol. 30 no. 6)
pp. 66-76
Roberto Airoldi, Tampere University of Technology, Tampere
Omer Anjum, Tampere University of Technology, Tampere
Fabio Garzia, Tampere University of Technology, Tampere
Alexander Wyglinski, Worcester Polytechnic Institute,
Jari Nurmi, Tampere University of Technology, Tampere

An energy-efficient fast Fourier transform (FFT) algorithm for cognitive radio communication systems uses a homogeneous multiprocessor system on chip. The algorithm allows for pruning of inputs such that algorithm complexity can be reduced whenever several of the FFT inputs are zero. Results show that the pruning algorithm significantly reduces energy consumption compared to a nonpruned version.

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Index Terms:
multiprocessor system on chip, energy efficiency, cognitive radio, NC-OFDM, FFT pruning, parallel algorithms.
Roberto Airoldi, Omer Anjum, Fabio Garzia, Alexander Wyglinski, Jari Nurmi, "Energy-Efficient Fast Fourier Transforms for Cognitive Radio Systems," IEEE Micro, vol. 30, no. 6, pp. 66-76, Nov.-Dec. 2010, doi:10.1109/MM.2010.84
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