11.2 PDH Functions> E3 Pulse Mask
This function captures and analyzes E3 (34.368Mbits/s) pulse shape. The purpose of maintaining the correct pulse shape is to
reduce inter-symbol interference – if the logic 1s and 0s cannot be detected by the receiver correctly, bit and code errors will
result.
The pulse amplitude and overall shape are superimposed and compared with ITU-T G.703 pulse conformance template.
Telecommunications signals require specific load impedance for pulse mask compliance testing to be accurate. When high
frequency pulses are transmitted down a transmission line, a portion of the pulse will be reflected when and wherever it
encounters an impedance mismatch. The reflection is proportional to the impedance mismatch i.e. the greater the mismatch, the
greater the reflection of the pulse.
11.3 PDH Functions > E1 APS Testing
This function measures the Automatic Protection Switching (APS) limits of the network. APS applies the Multiple E1 Links and
enables network elements to re-route traffic to a backup circuit in the event of network failure or problems.
Test Procedure:
1. The TX150 should be connected to transmission system to ensure that the switching time is measured for the
service transported by the E1 links.
2. Ensure that no errors or alarms are present on the transmission system because this will impact the
measurement.
3. The measurement will be triggered by an Alarm Indication Signal (AIS)
4. The TX150 measures how long the AIS event remains present after the event is first recognized and will
continue to measure the total disruption time in the event of multiple disruptions.
TX150 e-Manual D07-00-023 Rev A02
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