User's Manual

Notice that when a voltage of 1 Vpp on I and Q kernel entrance is obtained, the parameter Mkr
displayed on the screen while using the HAPC software should be about 20. If not, there certainly
some hardware trouble.
- BoardGain : (Former BOARD_SPECIFIC_GAIN in the file EEPROM.H). This
parameter is expressed in dB and corresponds to the gain of the radio reception channel.
To calculate this parameter, a mean value being given to BoardGain (e.g 40), try to synchronise on a
test set (see the process described for the calculation of the parameter PwrVsAgcSlope).
When synchronised, read P1 the value in the field Pwr (HAPC software) and P0 the power level of the
test set. Then the value to be given to BoardGain corresponds to the difference between P0 and P1 if
there is no signal loss between the test set and the mobile.
e.g : The value given to BoardGain is 40.
The value in Pwr field is 56. It corresponds to a power of P1=-56 dBm.
The power level of the test set is P0 = -50 dBm.
Assume a signal loss L = -1 dBm.
Then BoardGain should be decreased by -P1+ (P0 + L) = 5 dB.
So BoardGain = 40 - 5 = 35 dB.
Notice that as soon as BoardGain is given a likely value (e.g 40 dB) the Agc loop works. BoardGain is
only usefull to get a good power measurement.
- TxPwrRampNbPts : number of steps of the Hamming power ramping. Up to now, 21 steps for
GISMO and GTI V1 radio and 23 steps for GTI V3 radio.
See below the description of the ParamPwRamp parameters.
- ParamPwRamp : (former structure ParameterPowerRamp in the file EEPROM.H). The values
following describe the Tx power level scheme for each of the 11 levels, level 5 to level 15 (GSM
phase 1) with 4 values for each level : PowerMin, PowerMax, DebNMin and DebCourbe.
The ramp up is constituted by 32 values each being loaded every ¼ bit in the kernel TxPower DAC
after the beginning of the ramp up. The ramp down is constituted by the same 32 values taken in an
inverted order.
The values are calculated by the software as following :
- The DebNMin first values are 0. Notice that DebNMin must be greater than zero otherwise a value
different from 0 could be left in the TxPower DAC after the ramp down.
- The n values between DebNMin and DebCourbe are the PowerMin values (n = DebCourbe -
DebNMin + 1). Notice that (DebCourbe + TxPwrRampNbPt) must be smaller than 31 otherwise
PowerMax couldn’t be reached.
- The TxPwrRampNbPts values following DebCourbe are obtained from a Hamming process between
PowerMin and PowerMax.
- The value for the (32 - DebNMin - n - TxPwrRampNbPts ) = (31 - DebCourbe - TxPwrRampNbPts)
steps remaining is PowerMax.
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