User's Manual

ManualsBrandsDamm Cellular Systems ManualsElectronicsDOOR SYSTEM-TX

Doc. No.

Rev.

Date

DRAFT

1.01

2012-01-27

Damm Cellular Systems A/S, Denmark

TetraFlex

7.5 Manual - BS421 Configuration

TetraFlex® 7.5

Manual

2-73

The Damm BS system has a flexible system to provide synchronization between individual

Transceivers. Build-in GPS Receivers give absolute time synchronization to the radio cells.

External Inputs can also be marked as Primary Sync. References.

When a BS is Network locked, automatic frequency correction of the Master Oscillator (RX

and TX carrier frequencies) is provided, and Seamless Handover to other Network

Synchronized Cells is activated.

The BS can be setup to run as either Sync Master 0 to 4 or Slave. The Masters shall

preferably be provided with GPS antennas or an External Primary Sync source. The

remaining BS's shall be setup as Slave and does not need a GPS antenna.

The BS421 is provided with one External 1PPS (1 Pulse Per Second) output and two external

1PPS inputs. The Slaves shall receive external 1PPS inputs connected to Masters.

In addition to the hardware 1PPS, sync messages are send every second on IP from the

Masters to attached BS's.

A Master will indicate Master Mode, if:

1) Synchronized to the internal GPS RX or

2) Synchronized to an External Input marked as Primary and indicating Master Mode

The priority can be changed with OM command 72/MASTER/c

(c = 0-4 or S)

Master 0 priority:

1) Int. GPS RX

2) Ext. Master 1, Master Mode

3) Ext. Master 2, Master Mode

4) Ext. Master 3, Master Mode

5) Ext. Master 4, Master Mode

6) Ext. Master 1, Resync-only

7) Ext. Master 2, Resync-only

8) Ext. Master 3, Resync-only

9) Ext. Master 4, Resync-only

10) Int. Free-Run

Master 1 priority:

1) Ext. Master 0, Master Mode

2) Int. GPS RX