User's Manual

So ThinDacValue = 512 - 180 = 358.
- PwrVsAgcSlope : (former D_PWR_VS_AGC_SLOPE in the file EEPROM.H). This
parameter is proportionate to the slope of the straight line describing the power on the antenna
expressed in dBm versus the Agc value loaded in the 8 bits Agc DAC.
To calculate the value to give to this parameter, multiply the previous slope by -128.
Notice that PwrVsAgcSlope = 128x128 / AgcVsPwrSlope.
e.g : if the slope is -0.4 dBm by Agc step, PwrVsAgcSlope = -128 x (-0.4) = 51.
Notice that the straight line describing the power on the antenna versus the Agc must be built when the
level on I and Q ADC is constant whatever the power on the antenna is.
To do so, the nominal software can be used when synchronisation is possible. To make the
synchronisation possible, the parameters ThinDacValue and RoughDacValue should be calculated as
described and likely values should be given to the parameters PwrVsAgcSlope (e.g 51),
AgcVsPwrSlope (e.g 320), BoardGain (e.g 40) and VoltageOrder (e.g 90).
Then one can try to synchronise on a test set (e.g HP 8922) and tune the power and then read the Agc
order for several value of power. The Agc order can be read in the top of the PC screen while using
HAPC software. The right field is the second Agc field of the second line of the parameters displayed.
It is just on the left of the Mkr field. Of course the value of the power on the antenna must be read on
the test set and not in the Pwr field.
Notice that the Mkr field should be rather constant while the power increase or decrease because of the
software control even if the parameters are not good, however, the calculation may be improved by
leading again the whole process using, the values obtained for PwrVsAgcSlope and AgcVsPwrSlope.
- AgcVsPwrSlope : (former D_AGC_VS_PWR_SLOPE in the file EEPROM.H). This
parameter is proportionate to the slope of the straight line describing the Agc value loaded in the 8 bits
Agc DAC versus the power on the antenna expressed in dBm.
To calculate the value to give to this parameter, multiply the previous slope by -128.
e.g : if the slope is -2.5 Agc step by dBm , AgcVsPwrSlope = -128 x (-2.5) = 320.
Notice that AgcVsPwrSlope = 128x128 / PwrVsAgcSlope.
See above, description of the PwrVsAgcSlope.
- VoltageOrder : (Former VOLTAGE_ORDER_VALUE in the file EEPROM.H). This
parameter is
expressed in step of Agc DAC. It allows to adjust the voltage on the I and Q kernel DAC egaliser
entrance.
The voltage should be about 1 V pp. If VoltageOrder is increased by one, the voltage on I and Q
increased by about 0.05 V.
To calculate the right value, give a likely value to this parameter, and measure the voltage when the
mobile is synchronised (see the process described for the calculation of the parameter
PwrVsAgcSlope). Then measure the voltage on the kernel DAC egaliser entrance and adjust the value
of VoltageOrder until the right voltage is obtained.
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