DE19721127A1 - Unidirectional paging network expansion method - Google Patents

Abstract

The paging network expansion method uses connection of the unidirectional paging network to a mobile radio telephone network via an interface in the form of a direct data connection, for direct data exchange between the paging network and the radio telephone network. A paging signal is transmitted to a terminal in standard format via the paging network, with transmission of acknowledgement signals for the paging call and/or other signals and messages via signalling channels of the mobile radio telephone network and the direct data connection interface.

Description

The invention relates to a method for expanding a unidirectional paging network to a quasi bidirectional Paging network, as well as a device and a terminal for Execution of the procedure.

Calls are usually made via a classic paging network, e.g. B. Cityruf, Scall performed. A GSM mobile radio network also offers limited paging functions via the Short Message Service (SMS). A full-fledged paging service, as is possible in radio paging in terms of functionality, number of subscribers and call throughput etc., cannot be reproduced and implemented by the SMS infrastructure for technical - and above all cost reasons. In principle, the following features between paging and GSM SMS can be highlighted in this context:
Call:
Advantages:

• - Almost nationwide supply
• - Good supply inside buildings
• - Very small receivers
• - High standby time (battery time)
• - Inexpensive

Disadvantage:

• - No acknowledgment function for the paging
• - High airtime consumption when transmitting Text, especially for nationwide Reachability.

SMS:
Advantages:

• - Almost nationwide supply
• - Acknowledgment function
• - Caching of messages
• - Location of the receiver possible (GSM Mobility management

Disadvantage:

• - Poorer care within Buildings
• - Low standby time, high power consumption of the terminal.

The paging is consistently one-way Communication, d. H. the participant has no way to send a message yourself. When paging the caller does not know whether the called party receives the message received or read. Here would be one Acknowledgment function is advantageous, through which the called party can Receipt of the message confirmed. To such a Acknowledgment function in conventional paging networks realize, two-way communication is required with the associated infrastructure of broadcasting and Reception facilities. Into the pager would also have to a sufficiently powerful transmitter unit integrated will.

Bidirectional paging networks have already been developed (e.g. in the USA, called TANGO).

However, for the reasons mentioned, these are only very difficult high investments in the infrastructure of the paging network realizable.

It is an object of the invention to propose a method to existing one-way radio paging networks for a quasi two-way To make paging ready, using the procedure low technical and financial expenditure can be realized should be.  

The object is achieved by the features of patent claim 1 solved. A device and a terminal for implementation The method is the subject of claims 19 and 24, respectively.

According to the invention, a paging network (paging network) and a Telecommunications network, preferably a GSM mobile radio network, with a common access (gateway) connected. This makes it possible to take advantage of the previous advantages of paging the missing Acknowledgment function of radio calls, which normally only possible in two-way paging networks. Of the Paging will continue to be sent in the paging network. The Acknowledgment takes place in the GSM network. Major advantage of Invention is that only existing infrastructures be exploited and no additional, costly Facilities are necessary.

Another advantage is that through the mobility management Function in the GSM network to determine the location of the receiver becomes possible. This can lead to the paging zone assignment of the Receiver and thus to save airtime in the paging network be used. The required airtime of a radio call is a measure of the transmission capacity and utilization of a radio network. The necessary modifications are in principle independent of the standard of the paging network. The procedure is therefore can be used for any paging network.

Some paging systems (e.g. ERMES) transmit paging Area code to the pager, which enables the terminal to change the To recognize the paging area. When changing to one new paging area can be via GSM Short Message Service Mobile originated in the paging network a so-called paging area Update will be carried out.

The following advantages result from the method according to the invention reached:

• - Direct acknowledgment of radio calls possible;
• - Extended acknowledgment parameters possible (e.g. yes,  No, I'm calling back. . . );
• - Through mobility management in GSM is done by targeted transmission of the paging Airtime savings in the paging area, nationwide Accessibility (possibly international accessibility when using roaming connections);
• - By transferring the paging area to the network and management of the paging area is done by targeted transmission of the paging Airtime savings in the paging area, nationwide Accessibility (possibly international accessibility when using roaming connections);
• - New offerings with new applications possible;
• - Existing services in the GSM and paging network not affected;
• - Participants in the GSM or paging service have the Possibility to use the services of the other network as well to use;
• - Independence from the paging network standard used - thus also usable for future networks;
• - No new network structure necessary;
• - No new network standard necessary;
• - Subsequent implementation in existing Network infrastructure is possible at any time;
• - Minimal investment.

The coupling of a GSM network with a paging network can technically according to the invention through various concepts will be realized. The implemented in GSM Mobile Originated Short Message Service (for acknowledgment) and the mobility management function (for location determination) be usable.

The first concept sees the connection of the GSM network to the Paging network through a gateway with a short Message Service Center (SMSC) can be realized. A Integration of functionality into an existing SMSC possible. A modification of an SMSC according to the requirements  and use as an independent network node is exclusively for the application purpose according to the invention also possible. The Short Message Service Center e.g. B. the D1- Cellular network is already set up for the necessary gateway functions prepared.

A second concept sees the use of a special one Gateway computer through which the two networks without Modifications can be linked together.

In all concepts, two essential functions of the GSM standards used:

• - Mobility management for the localization of the end device and thus to determine the corresponding paging zone.
• - Mobile Originated Short Message Service to acknowledge the Paging.

The proposed concepts have the following special features Properties on:

• - There will be a call acknowledgment and a Location determination of the recipient allows, for this Functions no user channel (i.e. channel for the transmission of Language, data etc.) of the GSM network. The whole necessary exchange of information between terminal and short Message Service Center (SMSC) happens through Signaling channels of the GSM network.
• - It becomes standard at the SS # 7 interface to the GSM network GSM protocols used without modification. The corresponding Connection to the SS # 7 network is via a gateway. The required MAP signaling procedures are in every GSM Network implemented.
• - The acknowledgment function primarily becomes this used to indicate to the system that a paging successfully transmitted and received by the participant is, and therefore no new paging is necessary.

In a development of the invention it is provided that the Participants also payload (predefined and freely defined answers to the call) with the acknowledgment can send in a short message.

• - If the ERMES paging system is used, this transmits the paging area code, which makes it the Terminal is possible, a change of ERMES paging area to recognize. When changing to a new ERMES Paging area can be done using the GSM function Short Message Service Mobile Originated a so-called ERMES paging area Update will be carried out.
• - The one available through the GSM Mobility Management As an alternative to determining the location information Stay area of the terminal can be used.
• - To implement the acknowledgment is on the mobile radio side the GSM Short Message Service is required. There will be none Transfer voice information.
• - The normal operating state of the terminal is switched off Energy saving reasons a constantly switched on Pager and one (automatic) only for the GSM Location updates or ERMES paging area updates and Acknowledgment be switched on mobile radio part. The advantage is a very high standby time of the end device due to low Energy consumption of the cellphone part.

The location update procedure in the GSM network (for storing the Location of the GSM terminal in GSM databases) can - for energy saving reasons - via a timer controlled cyclically (automatic Switch on the mobile phone component and carry out a Location updates).

Is the cellular part switched off for a long time or if there is no radio contact, no location update can be made  be performed. The end device is located possibly already in a different area than the last one determined paging zone. If a call is now sent and not acknowledged within a predefined period of time, then there are the following options:

• - In principle, every unacknowledged call is repeated sent out.
• - The calls are in one by a time factor certain, constantly increasing radius around the most recently determined paging zone up to nationwide sent out.
• - The paging is made a second time e.g. B. nationwide which automatically sends a location when it is received
• - Update procedure for paging zone assignment is triggered.
• - The call is placed in the default call zone of the paging service

To the functionality resulting from coupling the networks to be able to make full use of the resulting possibilities appropriate end devices necessary. There are different ones Device configurations conceivable.

The "Economy" configuration is for existing ones Mobile subscribers suitable, or for those without the Use of new devices the advantages of the invention Want to use the procedure. There is a separate one GSM terminal and a pager terminal are used. Will be from Pager receive a message, so this can be done directly via the GSM device can be acknowledged. To transfer the Acknowledgment signals can also be the multi-frequency dialing method (DTMF) can be used. It is therefore also possible that Acknowledgment via any DTMF-compatible phone. In the GSM network it is Mobile Originated Short Message capable GSM end devices also possible, manually via the short Message Service to acknowledge the call.

"Expert" terminal

This system represents an independent terminal. This Terminal includes a pager (preferably a text pager) as well as a cell phone part, which only an SMS Has functionality. Both components are internal coupled via an interface (e.g. RS232). For operation the device becomes a normal SIM card with SMS authorization needed. It is sensible to use one designed only for this purpose SIM card. When a message is received via the pager is in a direct acknowledgment of the message with this terminal possible. The individual possibilities of acknowledgment and Location determination of the participant will be explained in more detail later. So that the mobility management of the GSM network in full The cellular component should be able to be used do not send an IMSI Detach Message. An execution as PCMCIA variant for laptops / palmtops is also conceivable. As a transition, normal text pagers with interfaces can be used be used. These can e.g. B. in a special Adapter in which the mobile radio part is implemented, be coupled.

"Vision" terminal

This system represents an independent device and includes a pager, taking advantage of the paging Infrastructure, as well as a fully "speaking" Cellular phone. A normal SIM card required. The pager can be integrated Paging receiver (e.g. city call or in the future via ERMES) via the paging infrastructure are called and via the GSM Confirm infrastructure.

Both devices are internal via a common interface coupled. A direct acknowledgment of the message is with possible on this device. The individual possibilities of Acknowledgment and location of the participant have already been explained. So that the mobility management of the GSM network in can be used in full, can be provided that the mobile radio component does not have an IMSI Detach Message sent.  

In the following the invention based on several Drawings illustrating execution paths explained in more detail. Here go from the drawings and their description further features and advantages essential to the invention Innovation. It shows:

Fig. 1 The principle of coupling a paging and GSM network;

Fig. 2 Simplified representation of the required network architecture;

FIG. 3 shows the coupling of networks in a first embodiment;

FIG. 4 shows the coupling of the networks in a second embodiment;

FIG. 5 Coupling of the networks in a third embodiment;

Fig. 6 Schematic structure of a suitable terminal;

Fig. 7 operating principle of the call acknowledgment with the "economy" terminal configuration.

Fig. 1 shows the general concept of the invention. In a known paging network 1 (e.g. city call, ERMES), a call signal 2 is sent to a terminal 3 which is set up to receive paging calls. In addition, the terminal 3 is GSM-compatible or at least can be coupled to a GSM mobile radio device. This makes it possible to use the terminal to send an acknowledgment signal 4 , which is associated with the paging, via the GSM mobile radio network 5 and which is received by a corresponding GSM switching center. Between the paging network 1 and the mobile radio network 5 there is an interface 6 through which a direct connection between the two networks is established. The acknowledgment signal 4 is transferred from the GSM mobile radio network 5 to the paging network 1 and registered or processed there. In addition, there is the possibility of locating the location area of the terminal 3 by means of the functions implemented in the GSM mobile radio network and making this location information available to the paging network. With this location information, the paging network is able to send out the paging in a targeted manner in the determined area of the subscriber.

The required network architecture is shown in simplified form in FIG. 2. The paging switch 7 of the paging network 1 , here in the example an ERMES paging network, has access to a switching center MSC of the GSM network 5 via a direct interface 6 and a gateway 20 . The responsible body for the management of the subscriber data in the paging network 22 is connected to the post-processing center 21 of the GSM network, so that common subscriber data can be accessed and exchanged between the two networks.

The customer interface 23 of the paging system enables third parties to initiate a paging and the acknowledgment of the paging z. B. to answer on his phone.

To implement the connection between the GSM network and Paging network there are three concepts:

Referring to FIG. 3, the connection of the two networks, the GSM network 5 and radio transmission network 1 is made by a gateway (access), which can be realized with a Short Message Service Center 10 (SMSC) of the GSM network. An SMSC already has gateway functions in GSM networks (especially the D1 network), ie it is prepared for a connection to external systems.

The SMSC 10 essentially consists of two components:

Interworking Entity 11 (IW Entity)

The IW Entity 11 represents the interface to the signaling standard of the GSM network and has a MAP interface (MAP: Mobile Application Part). Existing MAP signaling procedures allow the location of the subscriber and thus the paging zone to be determined, as well as the SMS procedures that are necessary to acknowledge a paging.

Service Center 12 (SC)

This is the actual service center. The service center 12 has, inter alia, a direct interface 12 to the switching center 7 (PNC: Paging Network Controller) of the paging network, which, for. B. can be a standardized X.25 interface (packet-oriented transmission). An X.25 interface must also be provided in the paging network controller 7 . The databases required for assigning subscriber and device identifications, for determining the location information and for storing the status information of radio calls (which are to be acknowledged) are implemented in the service center 12 . The databases in Service Center 12 have e.g. B. the following entries:

• - Participant identity IMSI / MSISDN
• - MSC identifier
• - Storage and evaluation of status information for each call:
  • - Radio call sent, await acknowledgment
  • - Acknowledgment has been made
  • - acknowledgment parameters
  • - Additional parameters for assigning the acknowledgment to a radio call that has already been sent (e.g. consecutive numbering of a radio call, date of receipt.)
• - Date / time of the last database action

Paging Network Controller (PNC)

The databases required for assigning subscribers (MSISDN / IMSI) and device identification (PagerID), for determining the location information and for storing further status information from the respective radio calls should be implemented in PNC 7 . Relevant subscriber data therefore only has to be administered and maintained at one point in the system. The PNC 7 needs the subscriber data in order to determine whether a radio call is to be sent to a subscriber and the procedures according to the invention are to be carried out.

At this point, the connection between paging and GSM subscriber data are produced.

The PNC databases have e.g. B. the following functions:

• - Assignment of the pager ID to the MSISDN / IMSI (and vice versa)
• - Assignment of the MSC identifier to the paging zone (s)
• - Storage and evaluation of status information for each paging, e.g. B .:
  • - Participant data
  • - specific data for each call
  • - Monitoring of transit times between paging and acknowledgment
  • - Storage of the last paging zone
  • - Acknowledgment status

The PNC 7 checks and compares the data as to whether a short message contains information for acknowledging a transmitted call. The PNC must also monitor the transit times between paging and acknowledgment and then decide whether to retry the paging.

According to FIG. 4, there is a further and inexpensive possibility of realizing the use of a special gateway computer 14 . The gateway computer is an aid with which access to the mobile radio network 5 is created. This makes it possible to monitor and display signal flows in the network, to simulate special signal flows and feed them into the network and to communicate with external components.

The gateway computer is a computer with an SS # 7 protocol stack and a connection to the SS # 7 network, which, after appropriate programming, can perform exactly the tasks described like a multilink monitoring system. By adding a component to the multilink monitoring system 14 that can also actively send signaling messages SS # 7, the functions described above can be achieved without modification of the existing Short Message Service Center (according to concept 1).

The databases for assigning subscriber and device identifiers, for determining the location information and for storing the status information of radio calls can, for. B. be implemented on a separate database server, similar to Concept 1, which is connected to the gateway computer 14 via a suitable interface 16 in order to relieve it of complex database operations. The gateway computer 14 is connected to the switching center 7 of the paging system 1 via a suitable interface 17 . When configured for this application, the gateway computer essentially consists of two components:

a. Module for SS # 7 communication

This module provides analogous to the interworking entity of the SMSC is the interface to the 55 # 7 network and has the Ability to generate and send GSM MAP messages as well as decode incoming GSM MAP messages. Thereby the system can communicate with GSM network components and the GSM MAP procedures for acknowledgment and localization To run.

b. Module for communication via network

The multilink monitoring system is activated via this component a network for communication with the PNC is connected.

FIG. 5 shows a further possibility of the network connection between a GSM mobile radio network 5 and an ERMES paging network 1 . The network architecture used essentially corresponds to that of concept 1 according to FIG. 3.

The connection of the GSM network 5 to the paging network 1 , for. B. via an X.25 interface, is in turn achieved by a gateway implemented in the SMSC 10 . The SMSC 10 is connected to the GSM network 5 via an SS # 7 interface. The paging area code (paging zone code) broadcast periodically by the ERMES paging network 1 is received by the terminal 3 and transmitted by short message to the SMSC 10 (signal 4 ') and from there via the X.25 interface to the PNC 7 of the paging network. The paging network thus “knows” where the paging receiver 3 is located, so that a targeted transmission of a paging call to the respective terminal 3 is possible. The GSM location update procedure for the call zone determination of the terminal 3 is not required.

Under certain circumstances, it is possible for a location update (signaling 24 ) to be carried out automatically when the terminal 3 is logged into the GSM network 5 . However, by using the transmitted paging area code, it is not necessary to convert the determined GSM location into a corresponding paging zone and to notify the PNC 7 .

The possibilities for localizing the terminal are described with reference to FIGS. 2 and 3:
The service center 12 receives the request from the paging network 1 via the cross-network interface 13 to determine the (last known) location of a terminal 3 . The IW entity 11 uses a signaling procedure to determine the identifier of the GSM switching center (MSC), which supplies the subscriber at the moment. The MSC identifier is converted into a corresponding paging zone in the service center 12 or in the paging switching center 7 . This works across the GSM network and can even be used for foreign paging zones thanks to international roaming (GSM and ERMES). GSM networks are divided into different MSC areas, which can be assigned to the corresponding paging zones of the paging network. The determined paging zone is transmitted to the paging network 1 and the paging is then deliberately emitted only in this zone. This leads to immense airtime savings.

In the service center 12 , a database entry is created which contains the status and important parameters for the paging or the acknowledgment of the paging.

If the GSM mobility management is to be used in full, it makes sense that the special terminal 3 does not send an "IMSI Detach Message". By transmitting an IMSI detach message before each switching off of the GSM terminal, the transmission of the location information is prevented, which is undesirable in the application according to the invention. If the transmission of the IMSI Detach Message is nevertheless permitted, the procedure does not return an MSC identifier if the mobile radio device is switched off. For a sensible use of the mobility management, however, it is necessary according to the invention that an MSC identifier is always returned which indicates the location of a mobile radio telephone at the MSC level.

As stated, it makes sense to use the IMSI Detach Message suppress, however, it is not mandatory to to use the invention.

It is not possible to send the IMSI Detach Message suppress, before sending the radio message through a "system call" prompting the terminal, a Perform location update in the GSM network and thus a To enable determination of the lounge area.

The normal operating state of the terminal is switched off Energy saving reasons a constantly switched on Paging receiver and only for the location and the Acknowledgment must be activated GSM mobile radio part.

Application and possibilities of localization:
The location update procedure in the GSM network (for location determination) can be carried out cyclically / periodically - for energy-saving reasons - using a timer (automatic switching on of the mobile phone component and implementation of a location update) or manually by pressing a button as "follow-me" -Function. It would also be conceivable to program this timer using a special radio call or a short message to set different timer values depending on the mobility of the subscriber. If the mobile radio part of the terminal 3 is switched off for a long time or there is no radio contact, no GSM location update can be carried out and the terminal may already be in a different area than the determined paging zone.

Localization by transmission of the paging area code with short message (e.g. at ERMES). The paging network 1 regularly (at intervals of less than one second) sends out the current paging area, ie the paging zone identifier.

The terminal 3 receives and stores this current paging area and sends the paging area to the gateway 20 by means of an SMS mobile originated procedure via the GSM return channel 4 . The PNC 7 is informed via the gateway 20 and there an update of the paging area is carried out in the database for the respective subscriber entry (paging area update).

The terminal can use the paging area code broadcast constantly by comparison with the stored "old" paging Check area code to see if it is in a new paging area stops. The terminal recognizes that it is in a new one Paging area or the stored information about the paging area is lost becomes a paging area Update started. Through this paging area update procedure can be ensured that radio calls are always in the current Paging area will be sent.

In this concept, the GSM location update is only used for this required, the GSM component of the terminal in the GSM network log in and thereby send short messages enable.

The individual acknowledgment options are shown below presented in more detail. A switch from manual to automatic acknowledgment can be set on the end device be.

Acknowledgment of a radio call

The following section describes the procedure for Acknowledgment of a paging call via the Short Message Service.  

The procedure can be analogous to the concepts described be applied. The acknowledgment function is in the first Line used to indicate to the system that a paging successfully transmitted and received by the participant is and therefore no new paging is necessary (Acknowledge). In a further stage, from Participant user information (predefined or freely defined Replies to the call) with the acknowledgment in a short Message are sent (extended acknowledge).

Special short messages can be sent from terminal 3 to acknowledge a received radio call. To do this, you first need to log into the GSM network. The terminal sends a short message to the Short Message Service Center 10 . The service center 12 recognizes a short message that is intended to acknowledge a radio call. Certain parameters and possibly the text of the short message, which identify a paging, are determined / extracted by the service center 12 and corresponding information is transmitted to the paging network 1 , for example if the service center 12 detects that a due to the entries in the status database Paging has been acknowledged. The entry in the status database and the short message in the SC can then be deleted.

Automatic acknowledgment by end device

When a radio call is received, the Acknowledgment of the radio call (if there is GSM radio coverage). The pager switches this via the internal interface Mobile part and there is an automatic Acknowledgment via GSM after logging into the GSM network.

Manual acknowledgment

With manual acknowledgment the pager switches that Cellular part when receiving a message. Then done the acknowledgment manually by pressing Acknowledgment button.  

Advantage: very high stand-by times of the recipient low energy consumption of the cellphone part.

Generate a short message

After receiving a radio call, the logic of the terminal 3 generates a short message which contains all the data which are required to acknowledge the radio call. Data contained in the call (e.g. serial number of the message), system parameters (e.g. date and time of receipt) and data from the SIM card can be used for this. Information on the MSISDN of the subscriber, the destination address and the service center address must be available.

This is a "pure" acknowledgment d. H. the message to the Paging network that a specific paging broadcast and has been received, possible.

In addition to the pure acknowledgment "receive call", there is the option of transmitting additional user data to the gateway by transferring predefined answers (contained in the call) or self-defined texts in the short message to be formed. This user data can be transmitted from the gateway 20 to the PNC 7 by the acknowledgment procedure.

Further functions / applications:

• - The change from manual to automatic acknowledgment is adjustable on the terminal.
• - The subscriber can use the acknowledgment function for radio calls Switch active or passive in the paging system.
• - A non-acknowledgment of a message in one predefined period results in a call repetition.
• - A non-acknowledgment of a message in one predefined period or after repeated Call repetition has e.g. B. a nationwide call to Episode. If there is still no acknowledgment, could a corresponding information to an alternative pager / SMS The recipient or fax number can be deducted.
• - A manual acknowledgment via each DTMF telephone is through Entry of an acknowledgment code possible  
• - A confirmation of receipt can be in a corresponding Software to be integrated.
• - A confirmation of receipt can be sent via a Information service (e.g. voice server) can be requested.

The manual acknowledgment, according to Fig. 7 in the simplest case directly via the GSM terminal or any DTMF capable telephone carried eighteenth A location determination with the "economy" solution is not practical since the GSM terminal and pager are physically separate devices. The pager is operated in its normal paging zones or the call is only sent in these zones.

For an acknowledgment via DTMF-compatible telephones, either the code can be filtered out of the PNC 7 when a special dialing number is selected, or a further access 19 to the SMSC 10 must be created and the acknowledgment message identified and evaluated there.

Regardless of the method used, the following results basic procedure:

If a radio call is sent, the recipient of the message can carry out the acknowledgment directly via his GSM terminal or via any DTMF-capable telephone 18 . He has a personal acknowledgment code and receives e.g. B. for numeric and text calls via the call numbering function, the number of the radio call that must be acknowledged is communicated. Parameter transfers are also possible, e.g. B. Yes: 007; No: 4711.

As an example, the acknowledgment code can be structured as follows:
Access number for entering the acknowledgment code: 016x
Recipient's phone number: 1234567
Number of the call to be acknowledged: 2
Acknowledgment code: 007 (for yes)
Complete acknowledgment code. 016x 1234567 2 007

In addition to the pure acknowledgment "radio call received" there is the Possibility of passing parameters on the radio calls in GSM staggered responses, e.g. B. Yes, no, I call back etc. These predefined - but also by the participant self definable - answers can be selected and with the Acknowledgment signal are sent back.

The possible terminal configurations for using the method according to the invention will be described in more detail below with reference to FIG. 6.

A terminal 3 consists of the components paging module 25 , GSM module 26 and controller 27 . An external switch 28 can be provided, via which the user can switch off the GSM module in order to save battery capacity.

The terminal preferably has a display and additional control buttons (not shown). The Power is supplied by batteries or rechargeable batteries.

Paging module 25

The paging module 15 contains all the functionalities of a known pager. These may have been expanded to include additional functionalities:

• - Controlled by the controller 27 , the paging module can switch between the locking mode and non-locking mode.
• - It informs the controller 27 of the receipt of a paging message so that the message can be confirmed.
• - It informs the controller 27 of the loss of service on the current paging frequency
• If the paging module 25 is in the locking mode and the radio supply for the current paging frequency is no longer sufficient to receive paging messages, all paging frequencies are scanned. The list of those frequencies for which there is sufficient radio coverage is sent to the controller.
• The subsequence mask (SM) must be transmitted to the controller 27 on request.
• - A change in the SM, z. B. on the paging Air interface, must be communicated to the controller.

GSM module 26

The GSM module 26 consists of the mobile equipment and the SIM (Subscriber Identity Module). At least the functionalities that are required for acknowledgment operation are implemented in the GSM module. External modules such as keyboard, display, microphone and loudspeaker can be omitted. The GSM module is switched on or off by the external switch 28 . The GSM module can be activated or deactivated by the controller 27 . A switched-off GSM module cannot be activated by the controller 27 until it is switched on again via the switch 28 . The SIM in the GSM module is a standard SIM according to GSM 11.11. To operate the GSM module, the PIN on the SIM must be deactivated. From the perspective of a GSM network, an activated GSM module 26 behaves like a GSM terminal:

• - The activation of the GSM module 26 corresponds to the switching on of a GSM telephone by the subscriber. The GSM module will log into an available GSM network.
• An activated GSM module can transmit a GSM short message (SMS-MO) to the PNC specified by the controller at the request of the controller 27 .
• - If the GSM module is deactivated, there may be a Logout in the GSM network using IMSI detach.

The GSM module informs the controller 27 of the state of its mobility management (MM) sublayer, and of the success or failure of an SMS sent.

Controller 27

The controller 27 connects the paging module 25 and the GSM module 26 of the terminal 3 and controls activation, sending of short messages and deactivation of the GSM module 26 . Triggered by the paging module 25 , the controller 27 executes two procedures, the paging area update procedure and the acknowledge procedure.

The controller 27 can be implemented as an independent assembly or as a process in the control computer.

Paging area update procedure

With the paging area update procedure, the controller 27 ensures that the PNC is able to send messages to the terminal again after the loss of the old paging area. If the paging module 25 is in locking mode and the radio supply to the locked paging area is no longer provided, the controller 27 is informed of this and starts the paging area update procedure.

In the first step, the paging module scans the available ones Paging frequencies. The result is sent to the controller transferred to one of the following mechanisms carries out:

• 1) The operator ID (OPID) of one or more paging areas is identical to the home OPID (OPIDhome) or with the last used OPID:
  The controller 27 selects a paging area for this OPID. The selection is made with an equally distributed probability function.
  The controller 27 activates the GSM module 26 and transmits the selected paging area (OPID, PA) with a GSM SMS to the PNC. After successful transmission, the paging module 25 is brought into the locking state.
• 2) a) Neither a paging area of the last used one nor the home OPID are found:
  The paging module 25 is brought into the non-locking state, whereby paging messages are expected on all available frequencies.
• b) The GSM module 26 is activated and the list of the available OPIDs and paging areas is transmitted to the PNC via a GSM SMS. From this list, the PNC can select a network operator suitable for paging roaming and use it to transmit messages.
• c) As long as the terminal 3 is in the non-locking state, the available OPIDs and paging areas are continuously determined. If the list determined here differs from the last one transmitted, then if OPIDhome is not available, 2b) is executed, otherwise 1). It may be necessary to define a waiting time between two transmissions according to 2b). After the transmission of the short message, the GSM module 26 is deactivated.

If the external switch 28 of the terminal 3 is OFF, the GSM module 26 is not activated. The transmission of information to the PNC is considered to have failed and will be suspended until it is switched on.

The activation of the GSM part 26 and the transmission of an SMS should preferably take place in the time in which the paging pager does not expect any messages. This could be done by evaluating the subsequence mask (SM).

If the transmission of the parameters to the PNC fails, the controller 27 deactivates the GSM module 26 and tries a new paging area update attempt after a time to be defined. The paging module is brought into the non-locking state. As the number of unsuccessful paging area update attempts increases, the waiting time increases. The number of attempts is unlimited.

Paging area detach

The switching off of the GSM module 26 could be communicated to the PNC by a paging area detach. The GSM module 26 is activated before switching off, an SMS with content to be defined is sent and the GSM module 26 is subsequently deactivated. The paging module 25 is brought into the non-locking state. If the transfer fails, no further attempt is made.

Acknowledge procedure

The controller 27 starts an acknowledge procedure as soon as the paging module 25 indicates the receipt of a paging message in. First of all, the subscriber is informed of the receipt of the message and the possibility to select a manual confirmation (manual acknowledge). Thereafter, the controller 27 activates the GSM module 26 and transmits the confirmation for all pending messages that have not yet been confirmed, in the order of receipt, to the paging network center (PNC) in addition to those in the software with a short message answers predefined by the terminal, these can be expanded by any responses received with the paging message. If the manual confirmation does not take place within a defined time, an automatic confirmation takes place. As with manual confirmation, the GSM module is activated and a short message is sent to the paging network center (PNC) as confirmation for all pending messages that have not yet been confirmed, in the order in which they were received. After successful transmission of all confirmations, the GSM module is deactivated. The short message sent when a call is acknowledged contains the parameters RIC, paging area (OPID, PA) in which the message was received, time stamp and acknowledgment number in addition to the response that may have to be transmitted.

By transferring the paging area, an implicit paging area update is carried out with the confirmation. If the transmission was successful, the paging module 25 is lured to the OPID and PA transmitted in the process.

Failure of the acknowledge procedure

If the acknowledge procedure fails (automatically or manually), the GSM module 26 is deactivated. After a time to be defined, another acknowledge attempt is carried out. The waiting time increases with the number of unsuccessful attempts. The number of attempts is limited. The unsuccessful transfer due to a lack of radio coverage is displayed to the subscriber so that the subscriber has the opportunity to enter the GSM coverage area. Another attempt to transmit the receipt can be started by the participant pressing a button. The subscriber is informed of the successful transmission or the final failure to acknowledge messages.

Personalization of the end device

Since a standard SIM is used, the Personalization as with any GSM SIM. Here, however the PIN is deactivated.

The personalization of the terminal 3 is carried out as for the known pagers by the manufacturer or network operator. Not only RIC and SM are communicated here, but also the PNC number (SMS service center number). The RIC, SM and PNC number are stored in a non-volatile memory in the terminal.

Possible developments of the invention

If the subscriber has switched off his GSM terminal and is standing in GSM an SMS message for transmission, so it will redirected to his pager.

International roaming: There is international roaming Agreement with a foreign GSM network operator, the Service can also be used abroad if there is a corresponding paging system exists.

Intelligent Network IN functionality for enhanced call Forwarding: If mobile subscribers are not available and an important phone call cannot be placed through it a call is transmitted with the Prompt to switch on the mobile phone or to to enter the coverage area of the mobile network. The  Call forwarding conditions can originate as well be selectable depending on the time.

Call forwarding for important messages: alerting by Paging for urgent short message that is not broadcast can. The call forwarding conditions can originally as well as being time-dependent.  

used abbreviations

DPC: Destination Point Code (GSM)
DPPS: Data Post Processing System (GSM)
GMSC: Gateway Mobile Switching Center (GSM)
GSM: Global System for Mobile Communication (GSM)
GT: Global Title (GSM)
HLR: Home Location Register (GSM)
IW Entity: Interworking Entity (GSM)
IMSI: International Mobile Subscriber Identity (GSM)
MAP: Mobile Application Part (GSM)
DTMF: multi-frequency dialing
MTP: Message Transfer Part SCCP (GSM)
MSC: Mobile Switching Center (GSM)
MSRN: Mobile Station Roaming Number (GSM)
MSISDN: Mobile Station ISDN Number (GSM)
0 Operation and maintenance
OPID: Operator (ERMES)
PA: Paging Area (ERMES)
PAU: Paging Area Update
Pager ID: Pager Identification (ERMES)
PNC: Paging Network Controller (ERMES)
RIC: Radio Identity Code (ERMES)
SPC: Signaling Point Codes (GSM)
SS # 7: Signaling System Number 7 (GSM)
SC: Service Center (GSM)
SCCP: Signaling Connection Control Part (GSM)
SHS: Subscriber Handling System (ERMES)
SIM: Subscriber Identity Module (GSM)
SM-PP: Short Message Peer to Peer
SMS: Short Message Service (GSM)
SMSC: Short Message Service Center (GSM)
SMSMO: Short Message Service Mobile Originated (GSM)
SMSMT: Short Message Service Mobile Tenninated (GSM)
TCAP: Transaction Capability Application Part (GSM)
VLR: Visitor Location Register (GSM)
VMSC: Visited Mobile Switching Center (GSM)

Reference list

1 paging network
2 call signal
3 terminal
4 , 4 ' acknowledgment signal
5 GSM cellular network
6 interface
7 Paging Network Controller (PNC)
8 Mobile Switching Center / Visitor Location Register
9 Home Location Register (HLR)
10 Short Message Service Center (SMSC)
11 Interworking Entity (IW Entity)
12 Service Center (SC)
13 interface between GSM u. Paging network
14 Multilink monitoring system
15 Operation & maintenance
16 Administration
17 interface (cross-network)
18 phone
19 interface
20 access (gateway)
21 DPPS data post-processing
22 subscriber data management (in the paging network)
23 customer interface (e.g. for paging orders)
24 signal
25 paging module
26 GSM module
27 controllers
28 External switch

Claims (28)

1. A method for expanding a unidirectional paging network to a quasi bidirectional paging network, characterized in that the paging network is connected via an interface in the form of a direct data connection to a telecommunications network, so that a direct data exchange between the paging network and the telecommunications network is possible, the Transmission of radio calls to a terminal device via the radio call network and transmission of acknowledgment signals and / or other signals and messages from the terminal device via signaling channels of the telecommunications network, from which the transmitted signals are forwarded to the radio call network via the direct data connection and processed there. 2. The method according to claim 1, characterized in that the telecommunications network is a GSM cellular network. 3. The method according to claim 1, characterized in that the telecommunications network is private or public Telephone network is. 4. The method according to any one of claims 1 to 3, characterized characterized in that for the transmission of signals between the short message to the end device and the GSM mobile network Function (SMS) is used. 5. The method according to any one of claims 1 to 4, characterized characterized that the interface between a short  Message Service Center (SMSC) of the GSM network and a paging Network controller (PNC) of the paging network is provided. 6. The method according to any one of claims 1 to 4, characterized characterized in that the interface between a gateway Computer of the GSM network and a paging network controller (PNC) of the paging network is provided. 7. The method according to any one of claims 1 to 6, characterized characterized by the Paging Network Controller (PNC) via the interface a GSM Mobile Application Part (MAP) Protocol procedure in the GSM network can be initiated by the Location area of the terminal within the GSM network determine. 8. The method according to any one of claims 1 to 6, characterized characterized by the Paging Network Controller (PNC) via the interface is a location update procedure in the GSM network can be initiated to the lounge area of the To determine the terminal within the GSM network. 9. The method according to any one of claims 1 to 8, characterized characterized in that the location area of the terminal in GSM network of a corresponding GSM switching center is assigned and a corresponding paging zone of the Paging network can be determined. 10. The method according to any one of claims 1 to 6, characterized characterized in that the paging network constantly Paging zone information sent out by the terminal received and over the GSM return channel to the paging network Controller is sent back to the lounge area of the To determine the terminal within the paging network. 11. The method according to any one of claims 1 to 10, characterized characterized in that the paging signal only in the corresponding paging zone in which the Device was last localized.   12. The method according to any one of claims 1 to 11, characterized characterized that the required databases for assignment of subscriber and device identifiers to determine Location information and for storing the Status information of paging in the Short Message Service Center (SMSC) of the GSM network are set up. 13. The method according to any one of claims 1 to 12, characterized characterized that the required databases for assignment of subscriber and device identifiers to determine Location information and for storing the Status information of calls in a database server are set up. 14. The method according to any one of claims 1 to 12, characterized characterized that the required databases for assignment of subscriber and device identifiers to determine Location information and for storing the Status information of calls in the paging network Controllers are set up. 15. The method according to any one of claims 1 to 14, characterized characterized in that an unacknowledged call repeats is sent out. 16. The method according to any one of claims 1 to 15 thereby characterized in that an unacknowledged call in a previously defined call zone is sent. 17. The method according to any one of claims 1 to 16 thereby characterized in that an unacknowledged paging occurs several times in a constantly increasing call radius is transmitted. 18. The method according to any one of claims 1 to 17, characterized characterized in that the paging in the entire paging network is transmitted and automatically upon receipt in the terminal  a location determination of the recipient (location update procedure) triggers in the GSM network. 19. The method according to one or more of claims 1 to 18, characterized in that the paging in a foreign, with your own paging network via data exchange lines connected paging network is transmitted at least temporarily and that a transmission of acknowledgment signals and / or other signals and messages via signaling channels of a foreign telecommunications network, which is located in the area of the foreign paging network, and that the Forwarding of signals and messages to your own Paging network associated telecommunications network is made by which the transmitted signals via direct Data connections forwarded to your own paging network and processed there. 20. Device for performing the method according to claims 1 to 19, characterized by a direct data connection ( 6 , 13 , 17 ) between a gateway ( 20 ) of the telecommunications network ( 5 ) and a switching center ( 7 ) of the paging network ( 1 ) which data connection ( 6 , 13 , 17 ) acknowledgment and location information are transmitted. 21. Device according to claim 20, characterized in that the gateway ( 20 ) is a short message service center ( 10 ). 22. The device according to claim 20, characterized in that the gateway ( 20 ) is realized by a gateway computer. 23. Device according to one of claims 20 to 22, characterized in that a database ( 12 ) for storing and processing subscriber-specific and paging-specific data is set up in the gateway ( 20 ). 24. Device according to one of claims 20 to 22, characterized in that in the switching center ( 7 ) of the paging network, a database for storing and processing subscriber-specific and paging-specific data is set up. 25. Terminal for performing the method according to claims 1 to 19, characterized in that the terminal ( 3 ) is prepared for operation in both networks and comprises a paging module ( 25 ) for receiving conventional paging signals, an at least SMS-capable Mobile radio module ( 26 ), and a control unit ( 27 ) for connecting the paging module ( 25 ) to the mobile radio module ( 26 ) and for controlling activation, deactivation of the modules ( 25 , 26 ), for sending acknowledgment Messages and initiation of the paging area update procedure and / or cellular location update procedure. 26. Terminal according to claim 25, characterized in that the personalization of the mobile radio module ( 26 ) is carried out by a standard SIM. 27. Terminal according to claim 25 or 26, characterized in that it has a switching device ( 28 ) through which the mobile radio module ( 26 ) can be switched off manually. 28. Terminal according to one of claims 25 to 27, characterized characterized in that it is a full cell phone includes.