A17.3.3 Indoor-indoor propagation

The use of the Extended Hata model for indoor-indoor propagation introduces the following adjustments according to the relative location of the pair of transmitter and receiver.

Same-building condition

The first step is to estimate whether the transmitter and the receiver are located in the same building. This is done trough a statistic trial. Let us denote P the probability that the transmitter and the receiver are located in the same building. P is calculated according to the following scheme:

Table 82: Same-building probability

Transmitter and Receiver in different buildings

When transmitter and receiver are located in different buildings, the calculation mode is similar to the indoor-outdoor propagation mode but with doubled additional values.

Median path loss

  (Eq. 209)

where 

                                  (Eq. 210)

Where  and are the attenuation due to external walls as defined in the Rx and Tx side respectively.

Variation in path loss

        (Eq. 211)

Transmitter and Receiver in same building

In this latter case a specific propagation model is used:

Median path Loss

The corresponding median path loss is given by the following formula :

 (Eq. 212)

with

       (Eq. 213)

where :

L_wi         : loss of wall (default 5 dB)

L_f          : loss between adjacent floor (default 18.3 dB)

b           : empirical parameter (default 0.46)

d_room     : size of the room (default 4 m)

h_floor      : height of each floor (default 3 m)

h₂          : height of the receiver (m)

h₁          : height of the transmitter (m)

d           : the distance between the transmitter and receiver (m)

Variation in path loss

Variation in path loss is modelled as an additional log-normal distribution, in order to take into account the uncertainty of building design, furniture of the rooms, etc. Typically it is set to 10 dB.