LG U8210, Service Manual, Page: 177 / 231

B. DCS Freq. Comp. Calibration
- Purpose
This item contains the change in Tx power of 15 ARFCN (Absolute Radio Frequency Channel
Number) relative to a reference ARFCN (channel 663).
NOTE 15 ARFCN + 1 ref channel = 16 channels.
- Procedure Proposal
1. Load the highest DCS power as defined in the standard.
2. Measure frequency response of the phone across 16 different ARFCN.
3. The data structure for all Tx frequency-compensated NV items are laid out as in the following
example.
NV_DCS_TX_FREQ_COMP
-8,-2,0,3,5,5,-7,-6
NOTE The first data index will correspond to channel index 0 and so on until the last index is reached
for all channels. The data point for the reference channel will always be 0.
C. DCS RX Gain Range Calibration
- Purpose
This item specifies the RX gain from the antenna to the MSM for 16 frequencies in the DCS band.
- Procedure Proposal
Same as in previous section in GSM except this time set the gain range and phone mode to DCS with
injected power of -65 dBm. In DCS we will frequency compensate over 16 channels.
7.3.5 PCS 1900 Calibration Items
A. PCS Ramp Up/Down Calibration
- Purpose
This item contains the PCS normal Tx burst up/down-ramp DAC values for each power level.
When a PCS Tx burst is generated, it shall pass the ETSI standard power mask as well as Output RF
Spectrum due to Modulation and Switching (OSRF).
- Procedure Proposal
1. Set phone to PCS mode. Determine the DAC codes for each power level during steady state (flat
part of the burst). Each power level has a tolerance limit as shown in Table 7-1.
2. Let’s call X the power levels and Y(x) (i) the up ramp DAC value of X power level at iteration i ( we
have 30). We then have the following:
7. CALIBRATION
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