A Dynamic Power Limit Based on Measures of Brightness in CR-UWB

For cognitive radio combining ultra wideband (CR-UWB), if there are not any spectrum holes for a current radio environment, the power of CR-UWB must be limited not to interfere the primary user (PU). The interference temperature of radio environment is an equivalent temperature, and can not be measured in practice, so a dynamic power limit based on measures of brightness of radio environment is presented in this paper. Depended on an interference temperature constraint and cognitive function of CR-UWB, the dynamic power limit of CR-UWB can be obtained by a self-regulating emission mode, a two-dimensional working scenario depended on the distance measure and location is given, some numerical values of the dynamic power limit can be gained through computer simulation.