  Electromagnetic metasurfaces can be characterized as intelligent if they are
able to perform multiple tunable functions, with the desired response being
controlled by a computer influencing the individual electromagnetic properties
of each metasurface inclusion. In this paper, we present an example of an
intelligent metasurface which operates in the reflection mode in the microwave
frequency range. We numerically show that without changing the main body of the
metasurface we can achieve tunable perfect absorption and tunable anomalous
reflection. The tunability features can be implemented using mixed-signal
integrated circuits (ICs), which can independently vary both the resistance and
reactance, offering complete local control over the complex surface impedance.
The ICs are embedded in the unit cells by connecting two metal patches over a
thin grounded substrate and the reflection property of the intelligent
metasurface can be readily controlled by a computer. Our intelligent
metasurface can have significant influence on future space-time modulated
metasurfaces and a multitude of applications, such as beam steering, energy
harvesting, and communications.
