FOMi-E1/T1 Fiber Optic Modem

Features

Extends the range of E1/T1 signals over Fiber Optic links
Operates over Multimode or Single mode fibers
Transmission range up to 100 km using laser diode option
Conforms to all relevant ITU (CCITT) standards
Supports E1 balanced and unbalanced (COAX) interfaces
Full management of local and remote units from the front panel
Real time alarm indication for local and remote units, including dry contact external alarm
Transparent to framing (G.704)
Diagnostic loops according to ITU V.54 standard
Built-in V.52 BER tester
Modem card for LRS - 12, and double modem card for LRS - 24, 19" racks with SNMP management available

Description

The FOMi-E1/T1 Fiber Optic modem provides extended range for E1 (2048 Mbps) or T1 (1544 Mbps) signals over fiber optic cable.

FOMi-E1/T1 is designed to operate over several grades and sizes of fiber optic cable. The type of fiber optic interface chosen depends on the type of cable available and the operating distances required. Four optical interfaces are available:
- 850 nm LED for use over multimode fiber with typical distances of up to 5 km (3 miles)
- 1300 nm LED for use over singlemode fiber with typical distances of up to 38 km (24 miles)
- 1300 nm laser diode for use over single mode fiber for extended range up to 50 km (31 miles)
- 1550 nm laser diode for use over single mode fiber for extended range up to 100 km (62 miles).

FOMi-E1/T1 complies with ITU standards G.703, G.921 and G.956. The electrical interface includes circuits for recovering data and clock according to ITU G.703. It is transparent to E1 and T1 framing and operates with G.703 framed (G.704) or unframed signals.

FOMi-E1/T1's electrical interface complies with E1 or T1 standards. The following interface options are selectable:
- 75W unbalanced for E1
- 120W balanced for E1
- 100W balanced for T1.

Two versions of FOMi-E1/T1 are available: Master and Slave. The Master standalone version features a front panel LCD. The Slave unit has a blank front panel with a 20-pin connector. For cases where parameters of the slave or master unit have to be monitored or changed on the slave side, a Portable Control Unit (PCU) can be connected via the 20-pin connector (see Ordering).

The modem uses an in-band management channel for controlling and monitoring the remote unit. Both data and management are transmitted over the same fiber link, simultaneously, without interference.

Menu-driven software, available on the front panel, enables soft-select monitoring and adjusting the local and remote units.

LED status indicators and a supervisory port are provided for indicating system faults. The indicators available are optical ERR/AIS, electrical LOW/AIS. The supervisory port includes two dry contact closures:
- For major alarms (low level at the electrical interface or High Bit Error Rate at the optical interface)
- For minor alarms (AIS in electrical or optical interface).

Real time indication of system status is also provided on the front panel LCD for the local and the remote modem.

FOMi-E1/T1 is available as a standalone unit, as a card version for the LRS - 12 or as a double modem card for the LRS - 24 19" modem rack with SNMP management, which can accommodate up to 12/24 FOMi-E1/T1 modems.

The LRS - 12/24 cards and the attached standalone units can be managed from an ASCII terminal or UNIX HPOV platform software, connected to LRS - 12/24 by direct Ethernet connection.

RADview - a RAD SNMP management application is available for managing FOMi-E1/T1 and other RAD products.

The diagnostic facility of the unit includes different loop activation options and an internal BER tester. The available loops are:
- Local analog loopback
- Remote loopback. Loops and other management options can be activated from the front panel, from the PCU, from ASCII terminal connected to the LRS - 12/24, or from the central SNMP management station software. An internal BER tester that complies with V.52/511 pattern is also available.