User's Manual

Table Of Contents
Boomer II User Manual & Integrator’s Guide ______________________________ APPENDIX F – Guide to Desense
BM210012WT37 137 Copyright Wavenet Technology © November 2003
Each source must be identified and controlled. This
identification is at times difficult.
The host/terminal and modem must communicate the problem
at hand to attempt to correct it. This capability is not supported
by the Boomer II OEM modem.
Pulling the Harmonic away from the Channel Frequency
RF Network Issues
Each RF network has its own requirements for the subscriber device.
Most networks implement a coverage equalization scheme. This
consists of configuring the infrastructure sites such that their RF power
output is equal to that of the subscriber device.
Since most portable devices are battery operated, the transmitter power
of the portable units is relatively low. To compensate for this, the base
site transmitter power is decreased to a level equal to that of the
portable. The base site has a much larger and reliable power source,
and is capable of putting out more power. This would help overcome
desense problems that the portable unit incurs. Most network managers
prefer not to increase their site power because of ERP licence
limitations and cell overlap issues.
Network operators must consider ambient noise levels when designing
their coverage plans. Once the wireless modem and host/terminal are
engineered not to “self-desense”, other machines in the user’s
environment can still impact radio performance. These machines are
not usually within close proximity of the wireless modem antenna, and
have less effect. An FCC Class B radiator can impact the wireless
~
Amplitude
Fs
Fss
Fh
Fc
Fhs
Freq.
Fs Interference source fundamental frequency
Fss Shifted source fundamental frequency
Fh Interference source harmonic
Fhs Interference source harmonic shifted
Fc Channel frequency