@2013 6Harmonics Inc. All Right Reserved
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GWS Cmd >setrxatten 1 30
GWS Cmd >
The attenuator values will be set at the factory to provide the best combination of
RX Sensitivity and RX Linearity. The first attenuator is located between the LNA
and downconverter and is therefore at RF. In general this attenuator will be set to its
minimum attenuation “setrxatten 0 0”. The second attenuator is at the IF frequency
and is located after the channel select filter. The second attenuator is typically used
to trim the gain up or down in the factory to adjust for part to part variation during the
fabrication process. The gain of the GWS receiver is carefully set to allow the best
combination of RX linearity and sensitivity and is factored into the calculation of
RSSI.
In rare cases the user may find it beneficial to adjust the attenuator values. For
short links where the radio does not need to receive near its sensitivity, or which are
susceptible to strong interference, the user may find the radio performs better if the
first attenuator value is increased slightly, since this will reduce the amount of
interference incident upon the demodulator.
7.27 getrxatten command
The “getrxatten” command will return current setting for both attenuators:
GWS Cmd >getrxatten
FRxAtten : 10
RRxAtten : 30
GWS Cmd >
7.28 reboot command
The “reboot” command is to reboot GWS Node
GWS Cmd>reboot
8 Power Control and Link Configuration
For certain jurisdictions such as the USA the FCC has mandated that a TV Band
Device must use the minimum amount of power necessary in order to successfully
establish/maintain the communication link. In other jurisdictions there may not be a
requirement yet, but implementing good power control at the network level is
nevertheless recommended to minimize interference between nodes and to optimize
the aggregate throughput at the network.
8.1 Manual Power Control
For small networks the user may prefer to perform the power control manually to
have a good control over the interference and to balance the load between links.
