2N ATEUS 501101E, User Manual

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3. Functional 

Description 

Users mostly use their PBXs and GSM Gateways intuitively, without reading any 

instructions, or follow very simple instructions provided by an authorized person. The following 
functional description is therefore intended for technicians, who follow the instructions 
(depending on the PBX set-up) and solve any operational problems. 

3.1. Outgoing Call

3.1.1.  Picking Up the Line 

The PBX picks up a line the moment a subscriber picks up his or her handset and dials a 
number that is interpreted by the PBX as the “GSM Gateway Access“ code. This code 
depends on the PBX type and set-up. Some PBXs accept the GSM prefix as this code. 
Then, the user need have no worry that the call is made via the GSM Gateway. 

Note

: If the GSM Gateway is busy, the PBX can either give the caller the busy tone 

 or choose another connection (PSTN, or there may be more GSM 

Gateways with one PBX).

3.1.2.  GSM Gateway Ready Signalling 

The

GSM Gateway registers the off-hook (current inflow) immediately and then, if everything is 

O.K., starts sending its usual dialling tone 

. Now the subscriber can dial the number. 

Notes:

• 

As far as pulse dialing is selected, DTMF dialing can be used to enter programming 
mode and program GSM gateway by phone. In case of any other DTMF dialing, GSM 
gateway will answer by busy tone.

• 

 If there is no GSM signal, no SIM card has been inserted, no PIN code has been 
entered, or if there is another problem, the PBX transmits a special tone (see below – 
“Telephone Line Tones“). 

3.1.3. Dialling Receive 

The GSM Gateway is ready to receive pulse or tone dialling (according to the set-up). As 
soon as the subscriber starts dialling a number, the GSM Gateway mutes the dialling 
tone 

 (as with public telephone exchanges). The user must dial digits in no more 

than 6 second intervals; otherwise the number is regarded as complete and sent to the 
GSM network (this timeout is programmable).  

Note: 

Some PBXs analyse the whole number first and then transmit the dialling into the CO 

line (GSM Gateway). Here, the signalling type and the timeout depend on the PBX set-up! 

3.1.4.  Dialling End Recognition 

The GSM Gateway itself can recognize the end of some numbers according to their 
length. Moreover, you can set your GSM Gateway in such a way that the GSM Gateway 
accepts the ‘*‘ or ‘#‘ (for tone dialling only) symbols as the end of dialling. Otherwise, it 
waits 6 seconds after the subscriber stops dialling (the timeout is programmable). Then, 
the subscriber can hear a short tone   signalling the dialling end and the GSM Gateway 
transmits the received number into the GSM network. If the caller goes on dialling, the 
GSM Gateway will not accept the extra digits!

3.1.5. Connection Establishing 

In this moment, GSM gateway is making a connection, and it takes typically 8 seconds. During 
this time, the subscriber hears a special "call progress" tone (differs by GSM gateway model 
and version of software). Next, the subscriber usually hears the ringing tone 

 or another signal transmitted by the GSM network. The connection, 

however, is not established and paid for until the called party answers the phone. The GSM 
network signals this moment and the GSM Gateway can pass the information to the PBX. If 
this type of signalling is used (exceptionally), the calling party can hear a click in the earphone.