This paper introduces two cognitive radio (CR) systems: (a) heterogeneous type CR and (b) spectrum sharing type CR regarding its definition, usage model, fundamental system architecture, and developed prototype.
In cognitive radio networks, secondary users need to conduct spectrum sensing to properly detect the presence of primary signals that may have much lower power than noise plus interference power. In such a case, time-varying noise plus interference, which is briefly called noise uncertainty in this paper, can substantially degrade the sensing reliability of… (More)
—Non-coherent UWB receivers provide robustness against multi path fading at low complexity. The analog front-end of these receivers, however, is susceptible to narrowband interference (NBI), thus requiring NBI mitigation capability. NBI identification and NBI parameter estimation is the first step towards implementing effective NBI mitigation. We propose an… (More)