User's Manual

Table Of Contents
Bay Level Offset Calibration
68P64115A18–1
Mar 2003
1X SC 4812T Lite BTS Optimization/ATP Software Release R2.16.1.x
DRAFT
3-84
or 3A). The signal travels through the inter–frame diversity RX
cables, into the RX expansion in ports (RX EXPANSION 1B, 2B, or
3B in NO TAG or NO TAG) of the companion frame, through the
Expansion MPC (EMPC) in SCCP cage slot MPC–2, the CIO, and
terminates at a backplane BBX slot in the SCCP shelf.
S RFDS sampling paths – Directional couplers for RFDS signal
sampling are integral to the SC4812T Lite transmit and receive paths
in the DRDCs and TRDCs. Cables connect from these directional
couplers to the RFDS input connectors.
Component Verification During Calibration
TX Path Calibration
TX path calibration supports verification of correct BTS installation, RF
cabling installation and performance, functionality of all equipment
installed in the transmit RF chain, and the proper functioning of each
transmit RF path. External test equipment is used to calibrate and audit
the TX paths of the BTS.
RX Path Calibration
RX path calibration is not required or supported on CDMA BTS
systems. Default RX calibration values are written to the RX calibration
data files during the TX calibration process. RX functionality is verified
during Frame Erasure Rate (FER) testing.
When to Calibrate BLOs
Calibration to determine BLO:
1. Is required after initial BTS installation.
2. Must be done once each year for an operational BTS site.
3. Is recommended by Motorola for all associated RF paths after
replacing any of the following components:
BBX card
SCCP shelf
CIO card
CIO–to–PA trunking module RF cable
PA trunking module
Power Amplifier
Trunking module–to–TX filter/filter combiner RF cable
TX filter or TX filter combiner
TX filter/filter combiner–to–DRDC/TRDC cable
DRDC or TRDC
BLO Calibration Data File
During the calibration process, the LMF creates a calibration (CAL) data
file where BLO values are stored. After calibration has been completed,
these offset values must be downloaded to the BBXs using the LMF
BLO download function. A detailed description of the file organization
and content is provided in the following paragraphs