Wi-Fi based localization research typically falls into
two distinct paradigms: radio propagation modeling and
radio frequency (RF) fingerprinting [8]. The former attempts
to infer the position of the target device using equations
that express wireless signals in the specific environment and
obviously it is very important and difficult of wireless signal
propagation parameter estimation to obtain an accurate
position due to the complex signal transmission pattern in
indoor environment [9]. Research like [9] has indicated that
the well-known log-normal shadowing model complies with
the following formula (1).