Atheros AP222A, Руководство пользователя

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COMPANY CONFIDENTIAL 35
CWMIgnExCCA
#iwpriv wifi N CWMIgnExCCA 1|0
This command allows the system to ignore the clear channel assessment (CCA) on the extension channel for
11n devices operating in HT 40 mode. Normally, to transmit, the device will require no energy detected on
both the control and extension channels for a minimum of a PIFS duration. This control will allow for ignoring
energy on the extension channel. This is not in conformance with the latest draft of the 802.11n specifications,
and should only be used in a test mode. The default value for this parameter is 0 (do NOT ignore extension
channel CCA). This command has a corresponding get command.
#iwpriv wifi0 CWMIgnExCCA 1
#iwpriv wifi0 GetCWMIgnExCCA
wifi0 GetCWMIgnExCCA:0
FIRStepLvl
#iwpriv wifi N FIRStepLvl level
This command will adjust the FIR filter parameter that determines when a signal is in band for weak signal
detection. Raising this level reduces the likelihood of adjacent channel interferers causing a large number of
(low RSSI) PHY errors, lowering the level allows easier weak signal detection for extended range. This
parameter is also modified by the ANI algorithm, so this may be change dynamically during operation, usually
in steps of single units. The default value for this parameter is 0. The command has a corresponding Get
command, but this returns the initialization (starting) value, and not the value that is currently in the operating
registers.
#iwpriv wifi0 FIRStepLvl 1
#iwpriv wifi0 GetFIRStepLvl
wifi0 GetFIRStepLvl:0
ForceBias
ForBiasAuto
#iwpriv wifi N ForBiasAuto 1|0
#iwpriv wifi N ForceBias Bias
This command activates the “force bias” feature. This is used as a workaround to a directional sensitivity issue
in the AR5133 PHY chip in 2.4 GHz bands. ForBiasAuto will automatically select the bias level depending on
the selected frequency. ForceBias will set the bias to a value between 0 and 7. These commands are only
available when the driver is compiled with the #define ATH_FORCE_BIAS parameter defined. Even when this
switch is enabled, the default values for both parameters are 0 (disabled). This should only be enabled if the
sensitivity issue is actually present.
The command has corresponding Get commands
#iwpriv wifi0 ForBiasAuto 1
#iwpriv wifi0 ForceBias 2
#iwpriv wifi0 GetForBiasAuto
wifi0 GetForBiasAuto:0
#iwpriv wifi0 GetForceBias
wifi0 GetForceBias:1