Page 168 - Integrated Wireless Propagation Models

146 C h a p t e r T h r e e

180'
(a) Horizontal (b) Vertical

/

\
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,
, ' ' \
,
I <- 2o 'o
I \I
' "
' I
I
/
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--
-
(d) Horizontal pattern at 84°
(c) 3D (--40 dB at origin) downtilt (-40 dB at origin)
FIGURE 3.1.7.1.3.3 Antenna model ALP8007-N.

collected measured data. This path loss exponent can then be used as an input to the
simulator to simulate the C/I and frequency reuse factor for the area. Measured data
were collected in Los Angeles. The path loss exponents were calculated using Lee's pre­
diction model. Based on the calculated path loss exponent and the C/I from the simula­
tor, in a dense urban area, the smart antenna system can support a K = 3 reuse scheme.
Since the number of cellular subscribers always continues to grow at a rapid pace in
a starting market, service providers are forced to find new methods to increase capacity
in their networks. Having sectors in a cell is a means of reducing co-channel interfer­
ence, and thus increase system capacity. However, it is associated with a trade-off in