The spectrum utilization ratio should be improved without harmful effect on current wireless systems and applications. This will greatly help to solve the bottleneck problem of spectrumscarcity.
In a recent presentation, the regulator's technical advisors compared "dire predictions" about the scarcity of spectrum to Thomas Malthus's grim prognostications in 1798 about the scarcity of food.
Using the licensed spectrum in "secondary utilization" way, cognitive radio provides a feasible solution for contradiction between spectrum resource scarcity and increasing radio access demands.