A.17.20.1 Description of the model

This path loss model was developed by ITU-R and its detailed description can be found in [1].  The model was developed for the evaluation of candidate IMT-Advanced Radio Interface Technologies in the frequency band 2–6 GHz and for the following environments: urban macro (UMa), urban micro (UMi), suburban macro (SMa), rural macro (RMa), and indoor hotspot (InH). Note that only outdoor scenarios UMa, SMa, and RMa are implemented in SEAMCAT. The path loss model from Report ITU-R M.2135-1 is an empirical path loss model based on measurements results carried out in IST-WINNER II project [2], as well as results from the literature. The model supports LOS and NLOS propagation conditions as well as the LOS probabilities. This model includes clutter loss and as such, it is not to be combined with the clutter loss model of Recommendation ITU-R P.2108-0.

Table 1: ITU-R M.2135-1 Path Loss model

Note 1:
Breakpoint distance dBP'=4hBS'hMS'fc/c, where fc is the centre frequency in Hz, c=3×108 m/s is the propagation velocity in free space, and hBS' and hMS' are the effective antenna heights at the BS and the MS, respectively. The effective antenna heights hBS' and hMS' are computed as follows: hBS'=hBS-hE, hMS'=hMS-hE, where hBS and hMS are the actual antenna heights, and hE is the effective environment height assumed to be hE=1 m.

Note 2:
Break point distance dBP=2πhBShMSfc/c, where fc is the centre frequency in Hz, c=3×108 m/s is the propagation velocity in free space, and hBS and hMS are the antenna heights at the BS and the MS, respectively.

SEAMCAT specific implementation:

hBS=maxhTx, hRx
hMS=minhTx, hRx

Table 2: LOS Probability

Scenario	LOS probability
UMa
SMa
RMa

Note: According to Report ITU-R M.2135-1, the LOS probabilities are used only for system level simulations.

In case the LOS probability is used, the path loss is computed as follows:

for a given Tx-Rx distance d:

• compute probability of LoS:  
• draw a sample value from uniform distribution 
• if   the path is LoS:

• else the path is NLoS:

where path losses in the LOS and NLOS conditions ( and ) and the LOS probability, , for a given scenario are shown in Table 1 and Table 2, respectively. 

A17.20.2 Input parameters

The input parameters for the path loss model ITU-R M.2135-1 are shown in Figure 1 and defined in Table 3.

Figure 1: GUI of the ITU-R M.2135-1 path loss model

Table 3: Parameters of the ITU-R M.2135-1 path loss model

References