Energy harvester based cognitive radio is a promising solution to address the
shortage of both spectrum and energy. Since the spectrum access and power
consumption patterns are interdependent, and the power value harvested from
certain environmental sources are spatially correlated, the new power dimension
could provide additional information to enhance the spectrum sensing accuracy.
In this paper, the Markovian behavior of the primary users is considered, based
on which we adopt a hidden input Markov model to specify the primary vs.
secondary dynamics in the system. Accordingly, we propose a 2-D spectrum and
power (harvested) sensing scheme to improve the primary user detection
performance, which is also capable of estimating the primary transmit power
level. Theoretical and simulated results demonstrate the effectiveness of the
proposed scheme, in term of the performance gain achieved by considering the
new power dimension. To the best of our knowledge, this is the first work to
jointly consider the spectrum and power dimensions for the cognitive primary
user detection problem