Page 391 - GuideFWA

SUMMARY AND CONCLUSIONS

• With dynamic channel assignment (DCA), the interference power on the
least-interfered channel must be studied to determine the effect of
interference.

• A simple teletraffic model based on Erlangs used by nearby FWA sites is
inadequate.

• The FWA transmitters will result in interference to the UPCS system that
can approach 50 dB above the thermal noise floor, on the least-interfered
channel.

• Interior building loss will in general not alleviate the problem.

• The FWA interference will severely impair the operation of UPCS
systems.

TWO-SLOPE PROPAGATION MODEL ADOPTED BY PCC-III
INTERFERENCE EXPERTS GROUP

? ??? 4p r ??? 2 4ht hr
?? ? ?
L(r) = ??????? r = rb with rb =
4p r 2 2 r = rb
?rb ?
?
?

ht and hr are transmit and receive antenna elevations (m)

? is wavelength (assumed 0.156 m)

r is distance between transmit and receive antenna (m)

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