Atec Tektronix-ST2400A - Manual (Page 6)

ST2400A
Receiver
Specifications
page 6
2.488 GBIT/S OPTICAL RECEIVER:
Type – InGaAs APD.
Input tolerance – ±20 ppm.
Wavelength – 1250-1600 nm.
Sensitivity – -28 dBm minimum at
10
–12 BER.
Overload – -10 dBm at 10 –12 BER.
Input reflectance – Better than –27 dBm.
Threshold offset – 100 settings, uncali-
brated. Initial setting optimized by factory
Range: ± 150 mV (typical).
2.488 GBIT/S ELECTRICAL INPUTS
AC-coupled 50
Ω
terminated ECL clock and
data interfaces; allow ST2400A to operate
error-free when electrical outputs are
looped to electrical inputs through a bias-
tee termination; data valid when sampled
within ±50 ps of center of data eye; SMA
connectors. ECL specifications: At high
input voltage, 25°C, –0.98 V (min). At low
input voltage, 25°C, –1.95 V (min)
and –1.63 V (max).
RECEIVER TIMING
Analyzer Clock Recovery –
Input Frequency Range: 2.48832 Gb/s
±20 ppm.
Input Jitter Tolerance: Meets Bellcore
GR-253-CORE and ITU G.825.
155/622 Mbit/s Output Timing – Derived by
dividing the clock recovered from the
Analyzer 2.488 Gb/s input.
Tributary Drop Interfaces – Allows payload
analysis using an external test set such as
the Tektronix CTS 850, CTS 710, or ST112.
155 Mbit/s Electrical:
75 Ω BNC CMI per ITU-T G.703 and
Bellcore GR-253-CORE (at 25°C ±5°C).
155/622 Mbit/s Optical:
Wavelength: 1310 nm (1273-1355 nm).
Minimum average power: –15 dBm.
Maximum average power: –8 dBm.
Category: I-4.1/IR-1.
Type: Class 1 laser per IEC 825-1 and
21CFR 1040.
PAYLOAD ACCESS
A selected tributary (1 of 16 155 Mbit/s or 1
of 4 622 Mbit/s) is dropped to an external
SDH or SONET test set, using the clock
recovered from the 2.488 Gbit/s input. Drop
Overhead: B1, B2 are recalculated; H1-H3
are copied from the selected channel. For
155 Mbit/s signal, the remainder of over-
head is copied from the first three columns
of the 2.488 Gbit/s input. For 622 Mbit/s
signal, the first three columns of the drop
signal are copied from the first three
columns of the 2.488 Gbit/s signal; the last
nine columns of the remainder are copied
from the selected drop channel.
Jitter transfer from 2.488 Gbit/s receiver to
drop interface is filtered by a 1 MHz
(nominal) bandwidth PLL, and divided down
to the drop rate.
Overhead Display: 2.488 Gbit/s, column 1 of
the first STM-1 or STS-3/3c transport over-
head bytes can be displayed as hex values.
Displayed bytes: A1, A2, B1, E1, F1, D1-D3,
H1-H3, B2, K1, K2, D4-D12, S1, E2. Clear-
text decoding (for easy interpretation of
G.707/GR-253-CORE message codes): S1
(Synchronization Status Byte), K1/K2 bytes
(APS – Automatic Protection
Switching/MSP – Multiplex Section
Protection).
Defect and Alarm Measurement: LOS, LOF,
OOF, AIS, MS-RDI/RDI-L. Status: Displayed
as front-panel LEDs with "history" button.
ERROR MEASUREMENT
SDH: B1, B2, B3, MS-REI per G.821 and
G.826; unavailability per G.827. Errored
Blocks, Errored Seconds, Severely Errored
Seconds, Unavailable Ratio, Unavailable
Seconds, Errored Seconds Ratio, Severely
Errored Seconds Ratio, Consecutive
Severely Errored Second Periods, Back-
ground Block Errors, Background Block
Error Ratio, Total Count, Available Errored
Blocks, Available Errored Seconds, Available
Background Block Errors, Available Severely
Errored Seconds, BER.
SONET: B1, B2, B3, REI-L per GR-253-
CORE. Errored Seconds, Severely Errored
Seconds, BER, Total Count.
B1, B2, MS-REI/REI-L Status: Displayed as
front panels LEDs with "history" button.
ERROR REPORTING
Test Period –
Manual start/stop, timed start/stop, and
repeated gate.
Duration: 1 s to 99 days.
Resolution: 1 s.
Report Printout –
Comprehensive printout of alarms, errors,
performance analysis, test start/stop/
pause time.
Print on event, at end of test, both, or on
demand.
Event Log –
Previous tests held in memory for subse-
quent printing.
Alarms, error counts and S1 (SSM) byte
changes logged per second, output to
printer or PC as required.
REMOTE CONTROL
Interfaces –
IEEE-488.2 (GPIB) and RS-232.
Command Set: High-level ASCII.
Printer –
Interface: DB-25 translation of Centronics.
Signal: TTL.
Description: Byte serial ASCII printer inter-
face. Follows industry standard.
Connector: DB-25.
Drivers –
National Instruments LabWindows CVI or
LabView; Hewlett-Packard HP-VEE.
EXTERNAL REFERENCE TIMING INTERFACES
SDH: 2.048 Mbit/s or 2.048 MHz SETS input
per G.703, except that ST2400A input
requires ±40 ppm. BNC connector on front
panel.
SONET: 1.544 Mbit/s BITS input per ANSI
T1.101-1994, except that ST2400A input
requires ±40 ppm. Bantam connector on
rear panel.