Agilent Technologies E4428C, User Manual

Page: 293 / 700

Chapter 9 269
BERT
Measuring RF Loopback BERT with Option 300
Measuring RF Loopback BERT with Option 300
The following procedure uses the data looped back from the base transceiver station (BTS) to measure the
bit error ratio introduced by the BTS receiver when it is receiving coded data from the test equipment.
Timing synchronization must first be achieved between the BTS and the test equipment so that data can be
transmitted and received at the expected times. Synchronization is achievable either to a received broadcast
channel (BCH), to a received full rate speech traffic channel (TCH) in the GSM format, or a packet data
channel (PDCH) in the EDGE format.
Required Equipment
The following equipment is required to make loopback BERT measurements.
• VSA Series Transmitter Tester, model E4406A, with the following required options:
−
Option BAH - GSM Measurement Personality
NOTE
Option 202 replaces Option BAH in the VSA if EDGE support is required.
−
Option 300
−
321.4 MHz IF Output
• ESG Vector Signal Generator, model E4438C
−
Option 300
−
GSM/EDGE base station loopback BERT test capability (requires Options UN7,
001/601or 002/602, 402)
Connecting the Test Equipment
Refer to Figure 9-2 for connections to the ESG, VSA, and base station.
CAUTION
If the base station output power is to be greater than the VSA input power specification
(+30 dBm), an external attenuator needs to be inserted prior to the RF INPUT connector on
the VSA.