Page 397 - Integrated Wireless Propagation Models
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T h e   l e e   C o m  p r e h e n s i v e   M  o d e l -  I n t e g r a t i o n   o f   t h e   T h r e e   l e e   M  o d e l s    375





                                                                               Macro
                                                                                  Tx
                                                                                   *

                              Micro Tx                              �  �  �
                                                                   �
                                                                  �
                                                             - - - - �
                                 �                   1 2    1 1  .._, ;:,   � r--h � 0.87 m
                                                 1 4  1i .f. !'•  ...   p
                                               15 ��                              i
                                             1 6    •   100   .   •  8
                   Pico Tx                1 7   •    1  Terra1n   ·   •  7   6    I
                                                  I
                                        1 8    •   25 ml   1 contour   •   •      I  I
                       DO           20  1 9   •   •   : 30 m                      I  I
                                     ,  .         �   t                          "
                                                      +  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  �
                                                                  r1=2200 m
                                                   -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  �
                                                                r2=2300 m
               FIGURE 6.4.4.2  Calculation i l lustrated for test point 14.



                                          (2400
                                 A 1  = 20 log   )  = 9 dB
                                            850
               The received signal P, at point 14 is found as


                              P, = P , - y · log(�) - A  1  + G, ,(h,) + L + a
                                                    ff7
                                  ,
                                                    1 . 37
                                = -61.7 dBm - 34.8 log ( { ) - 9 + 0 - 4 + 3.1

                                                     0
                                = -61.7 dBm - 5.48 - 9   +  - 4   + 3.1 = -77 dBm
               Figure 6.4.4.2 shows how the test point 14 is calculated for the diffraction loss.
                  Figure 6.4.4.3 shows the complete "test environment" of this study with the terrain
               data. The size of the test environment was limited to a manageable scope so that effort
               can be focused on benchmarking Lee's three different models.
                  Figure 6.4.4.3 shows the coverage areas from each cell site. This plot demonstrated
               the importance of integrated models and the value of the propagation model based on
               the radio wave traveling along the human-made environment and natural terrain.



          6.5   How to  Use  Prediction T o ols
               In previous sections, we have given examples of design aspects in each particular sce­
               nario. In this section, we give a systematic procedure to guide the user in using the
               prediction tools that have been developed from the prediction models. Once we choose
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