ICC'13 WS - Fifth workshop on cooperative and cognitive networks (CoCoNet5)
2013
CoCoNet: KeynoteKey physical layer challenges for cognitive communications are sensing and communications.Within the sensing procedure the radio channel must be observed to find possible primary users, or to carrier sense other cognitive radios which are using the wireless resource.To ensure best performance, the ROC (receiver operating characteristic) of different sensing approaches gives best insight.It, however, very much depends on the sensing approach taken.Recent results show that major sensing improvements over standard OFDM can be obtained by using new capturing methods, based on GFDM (generalized frequency division multiplexing).For the cognitive radio communications to be allowed to communication the communications waveform and modulation must provide a very small out-of-band power radiation.This way primary users are not obstructed, or other secondary users can be densely packed within the band of cognitive operation.Also, the waveform and modulation chosen should have bandwidth scalability and should allow for spectrum aggregation.Hence, multi-carrier systems are a natural choice, i.e.OFDM, FBMC, or GFDM.A comparison shows the overwhelming benefits that can be achieved with GFDM, at a small cost in complexity.