Page 225 - GuideFWA

The average value of s is

=?sD2 f s (a )da = D - D = D (5-14)
2 3 6 (5-15)
a

0

and the CDF is

?Fs (x) x} x f s (a )da ? x x2 ? D
= Pr{s < = 0 = 4 ? D - D2 ? , 0= x = 2 .
? ?

5.1.2. Response [16] to Comments on PCC.III-919/97 [17]

5.1.2.1 Summary of the PCC.III Interference Experts Group

The PCC.III Interference Experts Group was committed to releasing a report on issues of
incompatibility between FWA and PCS interference at the September meeting of PCC.III in
Mexico City. Throughout its work program, most of the Group’s efforts focused on the problem
of adjacent-channel interference between Licensed PCS and FWA. As a result, there was
insufficient time before the report deadline to include material on cochannel interference between
FWA and UPCS in the report, which refers the reader to the two contributions (one from Lucent
[17] (reproduced in section 5.1.1) and one from Ericsson[18]) that were submitted on the
FWA/UPCS issue. These will henceforth be referred to as the “Lucent contribution” and the
“Ericsson contribution.” Both contributions were provided with the Report to members of the
PCC.III Plenary.

It is noteworthy that in assessing the adjacent-channel interference between FWA and Licensed
PCS, the Experts Group used a 1-dB rise in the noise floor as the interference criterion, and
computed the separation distances required to prevent the interference from exceeding that level.
It is also noteworthy that during the course of its work, the Group developed a table of system
parameters, and also adopted a propagation model. These are documented in the Group’s
meeting report from the Brasilia meeting (June, 1997).

Both the Ericsson and Lucent contributions were presented orally as well as in written form to
the Experts Group in Mexico City. There was significant discussion and debate, although
agreement could not be reached between the “DECT Proponents” and the other participants. In
the next section of this paper the main points of debate will be summarized and addressed.

5.1.2.2 Summary of the Contributions

The Lucent and Ericsson contributions take fundamentally different approaches to evaluating the
interference from Fixed Wireless Access systems to UPCS. Those approaches can be
summarized as follows:

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