User Manual

Optimization Overview – continued

PRELIMINARY 2

SC 4812ET BTS Optimization/ATP – CDMA LMF

July 1999

1-2

CDMA LMF Product Description

CDMA LMF is a graphical user interface (GUI) based Local

Maintenance Facility(LMF). This product is specifically designed to

provide cellular communications field personnel the vehicle to support

the following CDMA Base Transceiver Stations (BTS) operations:

 Installation

 Maintenance

 Calibration

 Optimization

Online Help

Task oriented online help is available in the LMF by clicking on Help

from the menu bar.

Why Optimize?

Proper optimization and calibration assures:

 Accurate downlink RF power levels are transmitted from the site.

 Accurate uplink signal strength determinations are made by the site.

What Is Optimization?

Optimization compensates for the site-specific cabling and normal

equipment variations. Cables that interconnect the BTS and Duplexer

assemblies (if used), for example, are cut and installed at the time of the

BTS frame installation at the site. Site optimization guarantees that the

combined losses of the new cables and the gain/loss characteristics and

built-in tolerances of each BTS frame do not accumulate, causing

improper site operation.

Optimization identifies the accumulated loss (or gain) for all receive and

transmit paths at the BTS site, and stores that value in a database.

 RX path starts at the ancillary equipment frame RFDS RX directional

coupler antenna feedline port, through the RX input port on the rear of

the frame, through the DDRCs, Multicoupler Preselector Card (MPC),

and additional splitter circuitry, ending at a Code Division Multiple

Access (CDMA) Channel Processor (C–CCP) backplane Broad Band

Transceiver (BBX2) slot in the C–CCP shelf.

 A transmit path starts at the BBX2, through the C–CCP backplane

slot, travels through the LPA/Combiner TX Filter and ends at the rear

of the input/output (I/O) Panel. If the RFDS option is added, then the

TX path continues and ends at the top of the RFDS TX directional

coupler antenna feedline port installed in the ancillary equipment

frame.

These values are factored in by the BTS equipment internally, leaving

only site specific antenna feed line loss and antenna gain characteristics

to be factored in by the CFE when determining site Effective Radiated

Power (ERP) output power requirements.