Chapter 11 Using The Radwin Gsu; What Is It For; Radwin Gsu Functionality; Typical Gsu Scenarios - Radwin 5000 HPMP User Manual

Chapter 11
Using the RADWIN GSU

What is it for

The GPS-based synchronization unit (GSU) is designed to handle inter-site interferences
under large-scale deployment scenarios.
The RADWIN GSU (or just GSU for short) is an outdoor unit consisting of a standard WinLink
1000 enclosure, a GPS antenna and a PoE device.
The GSU is connected to the HSS Unit using a standard HSS cable. It synchronizes the trans-
mission timing of multiple Hub-Sites to the same clock source thus eliminating self interfer-
ence.

RADWIN GSU Functionality

The GSU receives a synchronization signal from the GPS once per second. It distributes a
RADWIN proprietary synchronization signal to all other ODU units using the RS422 protocol
and the standard HSS mechanism, where the GSU acts as an HSM unit.
When the GSU doesn't receive a synchronization signal from the GPS for 30 seconds, it moves
automatically to Self-Generation mode and acts as a regular HSM unit, until the GPS recovers.

Typical GSU Scenarios

Independent Distributed Sites
In the scenario of Figure 11-1, we have multiple independent collocated sites, which may
interfere with each other. To meet this situation, we coordinate all of them using the GSU as
shown.
The GSU functions like "wide area HSS unit", ensuring that all participating radios at the loca-
tions marked GSU each transmit and receive at the same time.
RADWIN 5000 HPMP User Manual Release 3.3.30 11-1