RAD Data comm E1 User Manual

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Chapter 1  Introduction 
FOM-E1/T1 Installation and Operation Manual 
1-4 Functional 
Description
 
 
Signal Conversion 
Conversion of the electrical signal into an optical signal takes place by using an 
infrared light-emitting diode or laser transmitter. At the opposite end of the fiber, 
the optical signal is converted back into an electrical signal and amplified to the 
required level. 
Data/Clock Recovery 
To recover data and clock from the signal, a Phase Locked Loop (PLL) circuit is 
utilized. FOM-E1/T1 provides internal selection for the E1/T1 electrical interfaces. 
Data Transfer 
The optical signal is linked to the fiber-optic media and transmitted via the optical 
link to the remote unit. A high sensitivity pre-amplifier and an AGC (Automatic 
Gain Control) circuit enable the remote unit to receive the optical signal. The 
output of the receiver is applied to the clock recovery circuit and the data 
regeneration circuit, which in turn apply it to the electrical interface driving circuit.