User's Manual

Bay Level Offset Calibration – continued

3-118 1X SC 4812T Lite BTS Optimization/ATP FEB 2005

PRELIMINARY

Table 3-39: Set–up Test Equipment for RF Path Calibration Procedure

n ActionStep

! CAUTION

To prevent damage to the Test Equipment, all Transmit (TX) Test Connections must be via the 30

dB Directional Coupler for 800 MHz or via a 30 dB Coupler with a 20 dB In–line Attenuator for

1900 MHz.

4 For TX Path Calibration, connect the Test Equipment as shown in Figure 3-16, Figure 3-17, or

Figure 3-18, depending on the Communications Analyzer being used.

Transmit (TX) Path Calibration

Description

The assigned Channel Frequency and desired Power Level at the Frame

TX Ports for transmit Calibration are derived from the BTS CDF File.

Each BBX at the site is assigned to a Sector and Carrier. These are

specified respectively in the Sector and Carrier Fields of the

“ParentCARRIER“ Parameter in each BBX Cards CDF File Block.

The Channel Frequency and desired Power Output for the assigned

sector are specified respectively in the “ChannelList“ and

“

SIFPilotPwr“ Parameters of the CDF Block for the CARRIER to

which the BBX is assigned.

Ensure that the bts–#.cdf (or bts–#.necf) and cbsc–#.cdf

Files loaded on the LMF Computer are current. The LMF

will obtain carrier and channel information from these

files and insert it into the appropriate CDMA Test

Parameter Screen.

Failure to have the most current files from the CBSC can

result in incorrect channel information being used to

calibrate the BTS and unfavorable affects on BTS

performance.

Carrier and Channel Numbers should only be entered

manually for special test cases or as a last resort.

NOTE

The Calibration Process attempts to adjust the measured Power Output

to within +0.5 dB of the desired Power Output. The Calibration Settings

will pass if the error is less than +1.5 dB.

The TX BLO for the SC 4812T Lite is approximately 45.0 dB +

5.0 dB.

BLO is the Gain in dB between the known Power Output of the BBX

and the measured Power Input at the TX Port. BLO is derived by

deducting the known BBX Power Output from the Power Input

measured at the TX Port or (Measured TX Port Power Input) – (BBX

TX Power Output).