Page 243 - Integrated Wireless Propagation Models
P. 243

M i c r o c e l l   P r e d i c t i o n   M  o d e l s    221

                    20.00
                     0.00
                   -20.00   §,a
                 E'       i   +
                 � -40.00   '&
                            ��                         Pred�ted
                 U5  -60.00     19 +  +       +  ;
                                 +
                                        � +it-
                 (j')         t  1 V��  -i
                 c:                         + +�  +
                   -80.00                �  +     *  ++-n.  .L  +
                                                               +
                                                                      n  co
                                            + r  f\1   + +++   '],.  !  + '+��  fu +�  <f!l  co  "'']
                                                    t  ,(" ++ +  ++  +  {tt
                  -100.00                                 +    +   0   "'  "'  :t     + +  pooco�
                                                                                ;:
                                                                               ++ + :+ -¥-
                                               MeasU:ed           +              +
                  -120.00
                        0.00  500.00  1 0 00.00 1 5 00.00 2000.00 2500.00 3000.00 3500.00 4000.00 4500.00
                                                 Distance (feet)
                                                     (a)
                       1 . 00
                                                      �
                                               �
                       0.80
                                      /
                       0.60
                    LL
                    0
                    0           �
                       0.40
                             j
                       0.20
                           J
                       0.00
                          0.0     5.00     1 0 .00   1 5 .00   20.00   25.00   30.00
                                                  Delta (dB)
                                                     (b)
                                                                             M
               FIGURE 4.2.7.9  Stair-run case: measured versus predicted on Front Street at 844  H z. (a) RSSI
               of measured versus predicted. (b) CDF of the deviation between measured and predicted.


               these picocell sites can be much lower than the surrounding buildings. This will be
               discussed in more detail in the next chapter, as one must consider some in-building
               situations more carefully so that coverage, cost, and capacity can be balanced.
                  Figure 4.2.8.3 shows the building height clusters in different colors. Depending on
               the distribution and height of these buildings, the propagation characteristics over the
               radio path vary. The propagation model needs to have the ability to integrate these
               characteristics in a proper and effective manner. Based on the work from the Lee mac­
               rocell model with the automorphology factors described in Sec. 3.3, these factors and
               functions can be easily added to the Lee Microcell Model.
                  From a measurement integration perspective, some cities have both old and mod­
               ern buildings coexisting in the same vicinity. Applying one empirical curve for the
               building loss might not provide an accurate result. The measurement data need to be
               integrated into the attribute file to make the prediction more accurate. The model can
               thus derive the building loss curve based on the building material. The model can add
   238   239   240   241   242   243   244   245   246   247   248