Moreover, different sensors (Fig. 1) not strictly
related to communication are integrated such as
Complementary Metal-Oxide Semiconductor (CMOS) sensors
of the camera to take pictures and record videos,
accelerometers to detect the rotation of the screen, and
GPS to use the smartphone as road navigator or to detect
possible loss of the smartphone. All these sensors permit
extending the smartphone from a communication device
to a measurement device [3] for monitoring health parameters
and quality of life.