User's Manual

Table Of Contents
Test Set Calibration
68P64115A18–1
Mar 2003
1X SC 4812T Lite BTS Optimization/ATP Software Release R2.16.1.x
DRAFT
3-80
Non-Duplexed RX Cable Calibration
Table 3-28: Calibrating Non–Duplexed RX Test Cabling Using Signal Generator & Spectrum Analyzer
Step Action
1
NOTE
When preparing to calibrate a BTS with duplexed TX and RX the RX cable calibration must be done
using calibration setup in Figure 3-23 and the procedure in Table 3-27.
Connect a short test cable between the spectrum analyzer and the signal generator as shown in
Figure 3-24, detail “A” (top portion of figure).
2 Set signal generator to –10 dBm at the customers RX frequency of 824.7–848.31 MHz for North
American cellular or 1850–1910 MHz band for North American PCS.
3 Use the spectrum analyzer to measure signal generator output and record the value for the detail “A”
setup.
4 Change the test setup to the one shown in detail “B” (lower portion of Figure 3-24) to measure the
output at the customers RX frequency (824.7–848.31 MHz for North American cellular or 1850–1910
MHz band for North American PCS). Record the value measured with the detail “B” test setup.
5
Calibration factor = (value measured with detail “A” setup) – (value measured with detail “B” setup)
Example: Cal factor = –12 dBm – (–14 dBm) = 2 dB
NOTE
The short test cable is used for test equipment setup calibration only. It is not part of the final test
setup. After calibration is completed, do not re-arrange any cables. Use the test cable configuration
as–is to ensure test procedures use the correct calibration factor.
Figure 3-24: Cal Setup for Non–Duplexed RX Test Cabling Using Signal Generator & Spectrum Analyzer
Spectrum
Analyzer
Signal
Generator
A
B
Spectrum
Analyzer
SHORT
TEST
CABLE
CONNECTION TO THE COMMUNICATIONS
SYSTEM ANALYZER RF OUTPUT
CONNECTOR DURING RX MEASUREMENTS
Signal
Generator
BULLET
CONNECTOR
RX TEST
CABLE
SHORT TEST
CABLE
CONNECTION TO THE BTS RX ANTENNA
CONNECTOR DURING RX ATP
IMPORTANT: IF BTS TX/RX SIGNALS ARE
DUPLEXED, THE RX TEST CABLE CONNECTS
TO THE DUPLEXED ANTENNA CONNECTOR
AND MUST USE/BE CALIBRATED WITH THE 30
DB DIRECTIONAL COUPLER AND 20 DB
IN–LINE ATTENUATOR. SEE FIGURE 3-23.