  Exploiting of nonlinearity has opened doors into undiscovered areas for
achieving multiplexed performances in recent years. Although efforts have been
made to obtain diverse nonlinear architectures at visible frequencies, the room
is still free for incorporating non-linearity into the design of microwave
metasurfaces. In this paper, a passive dual-band power intensity-dependent
metasurface is presented. Here, power-multiplexing performance is achieved by
embedding PIN-diodes in the coding particles. The proposed digital metasurface
has three operational states: 1) it acts as a normal reflector at low power
intensities whereas provides a dual-band nonlinear response upon illuminating
by high-power incidences where 2) it perfectly absorbs the radiations at f1=6.7
GHz and 3) re-distributes the scattered beams by arranging the meta-atoms with
a certain coding pattern at f2=9.37 GHz. The nonlinear performance of the
designed tri-state coding elements has been characterized by using the
scattering parameters captured in the full-wave simulations where the accurate
models of the nonlinear diodes are involved. The emergence of microwave
self-biased metasurfaces with smart re-actions upon illuminating by incidences
of different power levels, revealing great opportunities for designing smart
windows, smart camouflage coating surfaces and so on.
