Page 311 - Integrated Wireless Propagation Models
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I n - B u i l d i n g   ( P i c o c e l l )   P r e d i c t i o n   M  o d e l s    289

                  The received signal inside the room is



                                            Wall                                (5.2.8.3.2)
                                                            og  r +
                                                                        LOS
                                                                   LOS
                            _      " "         loss,  -�i=l  m   1  [(  d  ) ! d   )]
                                                   " "
                            - P LOS  - �i=l  mill wall ;   room
               where P, = received power in dBm in the room,
                   Pws = the power at the interception point of LOS and the first wall in dBm,
                     n = n umber of walls,
                       = the path-loss slope for each wall in dB I dec (obtained in Sec. 5.3.2.1 ),
                  m ill wa n
                 Wall = l oss due to the ith wall,
                    loss
                      ;
                      r = the mobile radial distance from the base transmitter to the mobile receiver
                        in meters,
                   m room  = the path-loss slope for inside the room in dB/ dec, and
                   dws = LOS distance from the transmitter to the first wall in meters.
                                                                                 = L o is
                  The general formula of the Lee model is shown in Sec. 5.3.5, where L ill wa n   ( )
                  expressed in Eq. (5.2.8.3.2).
               5.2.8.3.2   Measurement Integration  The success of any prediction model relies on taking
               advantage of field measurement data and fine-tuning the model formula for different
               environments. Due to the enhancement on the Lee model, the four curves shown in
               Fig. 5.2.8.3.3 can be adjusted through measurement integration.
                  As shown in Fig. 5.2.8.3.7, different setups are used in collecting measured data to
               tune the Lee model.
                  The first one will be in the LOS situation. In the LOS situation, two different cases
               need to be specified. One is within the Fresnel zone, and the other is after the Fresnel
               zone area. This needs to be distinguished so that behavior after the close-in distance can
               be further fine-tuned. Based on the measured data for handling this category, the path­
               loss curve can be derived. The various path-loss setups are highlighted in Fig. 5.2.8.3.8.







                                                                  e  LOS
                                                           0
                                                                  o  Non-LOS aggregate










               FIGURE 5.2.8.3.7  Measurement data collection.
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