User Manual

BTS Equipment Identification – continued

July 1999

1-15

SC 4812ET BTS Optimization/ATP – CDMA LMF

PRELIMINARY 2

Figure 1-4: SC 4812ET Intercabinet I/O Detail (Rear View)

RF CABINET

RFDS Expansion

RF Expansion

Exp. Punch

Punch

Block

27V

27V Ret

Conduit

Microwave

RF GPS

LAN

2 Sec

Tick

19 MHz

Clock

Ground Cable Lugs

1–3 Sector Antennas

4–6 Sector Antennas

Span/Alarm

Expansion 1

Pilot Beacon

Sector Configuration

There are a number of ways to configure the BTS frame. Table 1-2

outlines the basic requirements. When carrier capacity is greater than

two, a 2:1 or 4:1 cavity combiner must be used. For one or two carriers,

bandpass filters or cavity combiners may be used, depending on

sectorization and channel sequencing.

Table 1-2: BTS Sector Configuration

Number of

carriers

Number of

sectors

Channel spacing Filter requirements

1 3 or 6 N/A Bandpass Filter, Cavity Combiner (2:1 or 4:1)

2 6 Non–adjacent Cavity Combiner (2:1 Only)

2 6 Adjacent Dual Bandpass Filter

2 3 Non–adjacent Cavity Combiner (2:1 or 4:1)

2 3 Adjacent Bandpass Filter

3,4 3 Non–adjacent Cavity Combiner (2:1 or 4:1)

3,4 3 Adjacent Cavity Combiner (2:1 Only)