In Fig. 3.47 we show a curve labeled microcell model. This model has a breakpoint set to 100 m
(arbitrarily set) to convey the two-slope behavior. The model is given as generally as
(3.81)
where we have used the following values to plot the curve above
A 20
B 20
C 50
dbreak 100 m
PL cA B # log(d)
A B # log(dbreak) C # loga d
dbreakb
d dbreak
d dbreak
dbreak
4 # hBS # hMS
l
Next we move our attention to the macrocell environment where we have defined macrocells having
a radius greater than 1 km. At this point the breakpoint would have occurred already so the curves
are a straight line (when plotted on log scale). The following plots differ from presentations made in
other texts in that we have included additional countries in the comparison [7]. From a high level we
see the path loss curves have somewhat similar slopes but differing in the initial path loss offset. The
major exception being the path loss results pertaining to the NYC measurements. The macrocell path
loss summary is given below (see Fig. 3.48).
WIRELESS MULTIPATH CHANNEL 155
Microcell Path Loss Comparison
??“120
??“110
??“100
??“90
??“80
??“70
??“60
??“50
??“40
??“30
??“20
10 100 1000 10000
Distance (meters)
Path Loss (dB)
PL (London, 905 MHz)
PL(CA, 1.
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