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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 345

60 percent of the measured data. This is fairly good performance in a macrocell
prediction model.

6.2.2 Validation of the i crocell Model
M
In Sec. 4.2.7, measurement data were collected by different groups in various countries/
cities for selected applications with unique frequencies, varying transmitter heights,
and differing cell site parameters within a range of mobile communication environ­
ments. We must also consider different buildings that have unique shapes with indi­
vidual heights and widths and built with various materials and different spacing.
Measurement data were carried out in San Francisco, Japan, and Spain.
Comparisons with collected measurement data demonstrate that the model per­
formed exceptionally well in varying mobile environments with different cell site
parameters, as shown in Sec. 4.2.7.

(
6.2.3 Validation of the In-Building Model P icocell Model)
In Sec. 5.2.5, measured data were collected at the Qualcomm building. This set of tests
examined some special cases in the building, such as the impact of elevators on the
signal attenuation. LOS, NLOS, single room, and multiple rooms were considered.
Figure 5.2.6.1 shows the measured versus predicted charts. More than 85 percent of
the predicted values were within a delta value of 4 dB.

6.3 System Design Aspects Using Different Prediction M o dels

3
6. . 1 Preparing to Design a System
There are many technologies that can help to improve and enhance the COMA net­
work's coverage and capacity. However, the key consideration is the trade-off
among cost, benefit, and risk. In this section, three different new technologies are
analyzed and applied to a specific study area. The deployment of a microcell pro­
vides much enhanced capacity and coverage. The implementation of repeaters can
improve limited coverage but lose certain capacities. The masthead low-noise
amplifier (LNA) improves both the coverage (and with higher sensitivity) and the
capacity. First, we analyze the benefits from these technologies and then consider
the trade-off on the cost of improvement on a per-decibel basis. A system design is
conducted based on the terrain and ETAK data. Then the design criteria and link
budgets are analyzed and balanced. The Lee propagation model was applied to
come up with radio coverage plots from each cell site within the study area. Then
the COMA coverage plots (Ec/10 and E/10) for forward and reverse links are
derived. Based on these plots, the analysis on effects of applying these new tech­
nologies can be further studied and compared. As shown from these studies, each
technology has its own pros and cons.
The goal here is to study the modeled design and applying the new technology to
see if there are any of the following:
• Performance improvement
• Reduction of capital without affecting the service
• Associated cost and risk