In this chapter, we presented a novel soft decision cognitive radio and dynamic spectrum access paradigm which exploits not only the unused spectrum holes, but also the underused spectrum bands to maximize performance and channel capacity for secondary cognitive users. We reviewed commonly used multi-carrier based enabling waveforms for cognitive radio. We then extended the SMSE framework to generate such overlay, underlay, and hybrid overlay/underlay waveforms to support the soft decision cognitive radio. Performance analysis and simulation results over AWGN and fading channels were then presented to confirm the performance gain of the novel system.

Inspec keywords: AWGN channels; cognitive radio; fading channels

Other keywords: multicarrier based enabling waveforms; fading channels; overlay-underlay waveform design; dynamic spectrum access paradigm; hybrid overlay-underlay waveforms; soft decision cognitive radio; SMSE framework; secondary cognitive users; performance analysis; channel capacity; enhancing spectrum efficiency; AWGN channels

Subjects: Radio links and equipment