Heterogeneous coexistence between cognitive radio networks over TV white space: A nonlinear control perspective

An increasing number of different unlicensed wireless technologies have been deployed in the TV white space (TVWS). Because MAC/PHY designs of coexisting networks are incompatible, heterogeneous cognitive radio networks operating in the same TVWS spectrum may cause severe mutual interference, which further leads to performance degradation or even the inability to continue operation. Motivated by the competition relationship between different species in a stable ecosystem, this paper formulates the heterogeneous coexistence problem over TVWS as a nonlinear feedback control system (NFCS) based on the Lotka-Volterra competition model. With the differential mean value theorem, we can obtain a feedback controller to the NFCS via solving a sufficient condition in the form of linear matrix inequalities, based on which a spectrum sharing allocation algorithm (SSAA) is proposed to enable the NFCS to converge to any feasible spectrum share. It is shown that the SSAA is compatible with the IEEE 802.19.1 system. Finally, extensive simulations demonstrate the efficiency of the proposed SSAA