Having said this, there has also been some results in Germany and presented in Table 3.3 [89].
146 CHAPTER THREE
TABLE 3.3 Comparison of Micro- and Macrocell Results
Parameter Microcellular Macrocellular
RMS 2 sec 8 sec
excess 6 sec 16 sec
Staying along these lines of environment classification,
we have two items remaining: the first item
deals with results taken in US cities and compare
two cities on the West Coast to two cities on the East
Coast [90]. This is summarized in Table 3.4.
This difference is mainly due to the more dispersive
nature of the northern California region. We
have found that the West Coast German cities are less dispersive than the West Coast US cities. Also
note that the above published measurements are not exhaustive, but are meant to convey patterns.
The second item remaining is the choice of the PDP threshold to be used to remove unwanted
noise and interference. Below we present some results that show as the threshold is lowered, to effectively
include more echoes in the RMS calculator, the excess delay spread increases (see Fig. 3.39).
TABLE 3.4 Comparison between East Coast and
West Coast RMS Measurements in USA
East coast West coast
RMS (max) 7.5 sec 25.5 sec
Macrocell Excess Delay
0
1000
2000
3000
4000
5000
6000
7000
8000
??“30 ??“25 ??“20 ??“15 ??“10 ??“5 0
Threshold Level (dB)
Excess Delay (nsec)
A-910 MHz
B-910 MHz
C-910 MHz
D-910 MHz
MA-910 MHz
MB-910 MHz
FIGURE 3.
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