Atec Anritsu-MT8221B - Manual (Page 17)

17
BTS Master™ Base Station Analyzer Features
Backhaul Analyzers (Options 0051, 0052, 0053)
E1 Measurements (Option 0052)
Error Detection
Frame Bits, Bit Errors, BER,
BPV, CRC, E Bits
Error Analysis
Errored Seconds (ES)
Error Free Seconds (EFS)
Severely Errored Seconds (SES)
Unavailable Seconds (UAS)
Available Seconds (AS)
Degraded Minutes (DGRM)
Rx Signal
Frequency, Vpp (Max/Min), dBdsx,
Clock Slips, Frame Slips
VF
Frequency, Power
T1 Measurements (Option 0051)
Error Detection
Frame Bits, Bit Errors, BER,
BPV, CRC, PATLS
Error Analysis
Errored Seconds (ES)
Error Free Seconds (EFS)
Severely Errored Seconds (SES)
Unavailable Seconds (UAS)
Available Seconds (AS)
Degraded Minutes (DGRM)
Rx Signal
Frequency, Vpp (Max/Min), dBdsx,
Clock Slips, Frame Slips
VF
Frequency, Power
T3 Measurements (Option 0053)
Error Detection
Frame Bits, Bit Errors, BER, BPV,
Lof Count, P-bit Errors, C-bit Errors,
FEBE Errors
Error Analysis
Excess Zeros
Errored Seconds (ES)
Error Free Seconds (EFS)
Severely Errored Seconds (SES)
Unavailable Seconds (UAS)
Available Seconds (AS)
Degraded Minutes (DGRM)
Pattern Loss Seconds (PATLS)
Rx Signal
Frequency, Vpp (Max/Min), dBdsx
VF
Frequency, Power
Backhaul Analyzers
The BTS Master features three Backhaul
Analyzer measurement modes:
• E1 Analyzer
• T1 Analyzer
• T3/T1 Analyzer
The goal of these measurements is to
maximize throughput for the cell site so
the base station can operate at maximum
call capacity and data rates for a good
customer experience.
Wireless operators need to test the
backhaul circuits prior to acceptance
from the Telco and for troubleshooting
faults. When troubleshooting cell site
technicians or RF engineers first step is to
decide if the fault is on the Telco side of
the demarcation point or on the wireless
operator’s side, since that determines who
needs to fix the fault.
When identifying faults, the
troubleshooting can often be done by
monitoring an in-service signal, looking
for data related errors. However, in some
cases, in-service testing is not enough,
and an out-of-service test must be
performed.
E1/T1/T3 Bit Error Rate Test (BERT)
A Bit Error Rate Test will measure how
accurately a backhaul circuit can send and
receive data. BER testing is always an
out-of-service activity. Errors will cause
re-transmissions and a lower over-all data
rate. Large numbers of errors will shut
down the circuit.
Frame Loss
Frame Loss counts errors in the framing
bits. Framing errors do not accumulate as
fast as other errors. When monitored for
extended periods of time, framing errors
can become a valuable indication of signal
quality. Frame Loss results in lower, or no,
throughput.
Carrier Loss
Carrier Loss keeps track of times that the
carrier is interrupted which means the line
is dropped and the cell site is off the air.
Frequency Accuracy
Frequency refers to the number of bits
per second on the backhaul line. Poor
frequency accuracy leads to slipped frames
and data loss.
E1/T1/T3 Bi-Polar Violation (BPV)
BPVs occur when the polarity does not switch every
time a “1” is transmitted. BPVs are symptoms of low
signal quality and result in lower, or no, throughput.
E1/T1/T3 Rx Signal Measurements – Vpp
Unusually low Vpp leads to a high bit error rate or
alarms, loss of sync and loss of carrier. Unusually high
Vpp leads to signal clipping and bit errors.
Histogram – Cyclic Redundancy Check (CRC)
CRC errors result in a lower overall throughput for the
T1 link. CRC errors can indicate problems bad enough
to shut down the link.
VF Channel Measurements
Verifies the level and frequency of the VF Channel.
Through the speaker the tester can make an audible
assessment of the signal quality of the circuit.