ADTRAN 2 x E1 user manual Link Planning, P O R T a N T

61280004L2-1C

Section 2 Installation

Three loopback functions are provided for diagnostic capability of each E1 interface. The local line loopback (Loop 1 as illustrated in Figure 2-1) loops the incoming E1 signal back out at the E1 framer. The remote link loopback (Loop 3 as illustrated in Figure 2-1) loops the E1 data back to the local end from the remote end. This allows a BERT to be run across the microwave link and back. The local link loopback (Loop 2 as illustrated in Figure 2-1) allows the local unit to loop E1 data back towards the remote end. The available loopback functions are illustrated in Figure 2-1.

E1

1 2

Local

RF Link 3

Remote

E1

Figure 2-1. E1 Loopback Locations

LINK PLANNING

I M P O R T A N T

The appropriate transmitter power must be calculated as part of the link planning.

The factors that must be taken into account when planning a link are optimal received signal level, transmitter power, antenna feedline loss (each end), antenna gain (each end), free space path loss, and required fade margin.

I M P O R T A N T

The optimal signal level for the receiver is -60 dBm.

14 TRACER 2 x E1 User’s Manual