User Manual
Table Of Contents
- ExtendAir (TDD) Digital Microwave Radios Installation and Management Guide
- Legal Notice
- Open-Source License Information
- Table of Contents
- About this Document
- Introduction
- Pre-installation Tasks
- Link Engineering and Site Planning
- Familiarization with the ExtendAir (TDD) Radios
- Initial Configuration and Back-to-Back Bench Test
- Time Division Duplex (TDD) Factors
- Link Orientation and Synchronization
- Radio Synchronization
- Offset Timing
- Virtual Local Area Network (VLAN)
- Simple Network Management Protocol (SNMP)
- System Installation and Initiation Process
- Installation
- Configuration and Management
- Telnet into the Command Line Interface (CLI)
- Telnet
- Exalt Graphical User Interface (GUI)
- Quick Start
- Navigating the GUI
- Radio Information Page
- Administration Settings Page
- Simple Network Management Protocol (SNMP) Configuration
- File Management Pages
- File Transfer Page
- File Activation Page
- System Configuration Page
- Ethernet Interface Configuration Page
- T1/E1 Configuration Pages
- VLAN Configuration Page
- Ethernet Rate Limiting
- GPS Information Page
- Alarms Page
- Performance Page
- Event Log Page
- User Throughput Page
- Diagnostic Charts Page
- Spectrum Analyzer Page
- Ethernet Utilization Page
- Reboot Page
- Manual Page
- Specifications
- Interface Connections
- Antennas
- Troubleshooting
- Back-to-back Bench Testing
- General Compliance and Safety
- Dynamic Frequency Selection
- Safety Notices
- Regulatory Notices
- Regulatory Compliance
- Regulatory Domain Keys
- EIRP Limits for the United States and Canada
- EIRP Limits for Australia
- EIRP Limits for the European Union and ITU Countries
- Declaration of Conformity to the R&TTE Directive 1999/5/EC
- Exalt Limited Hardware Warranty
- Copyright Notices
- Index
Exalt Installation and Management Guide
ExtendAir (TDD) Series Digital Microwave Radios
203591-002 55
2009-12-18
T1/E1 Loopback
Loopback is provided for any enabled T1 or E1 port. As shown in Figure 26 through Figure 28, the
choices are:
• No Loopback (default)
• External (local)
• External (remote)
• Internal
All loopback configurations control the loop at the Line Interface integrated circuit, which is the
device wired directly to the front panel ports.
External loopback modes are used in conjunction with an external test source. The designation of
‘local’ or ‘remote’ refers to where the loopback is occurring relative to the location where the loopback
is implemented. That is, on the radio being accessed, if External (remote) is selected, this loops the
signal back at the remote radio interface back towards the local radio. Likewise, if External (local) is
selected, the signal loops back at the local interface towards the remote radio (Figure 26 and Figure
27).
Figure 26 External (remote) loopback
Figure 27 External (local) loopback
When a local T1/E1 port is configured for External (remote) loopback, it is the same as configuring the
remote radio for External (local) loopback.
Internal loopback uses an internal test source, and sends the test source signal across the link, looped at
the remote radio’s interface, returned to the local radio, and looped at the local radio’s interface back to
the source. The inputs at both ends are looped back at the line level. Figure 28 illustrates the internal
loopback function.
Figure 28 Internal loopback
Note: Only one Internal loopback can be enabled at any time.