JP2003502927A - Calling in mobile telecommunications networks - Google Patents

Abstract

(57) [Summary] A method of processing an incoming call and an incoming call signal in a control center of a mobile communication network (1) while the level of the incoming call signal is high. The method includes receiving paging signals at a control center (7), identifying a priority level of each paging signal, and transmitting a paging message corresponding to at least a portion of the paging signal to a communication network (1). Broadcasting to each registered mobile station (3). A paging message corresponding to a paging signal with a higher priority level is broadcast before a paging message corresponding to a paging signal with a lower priority level.

Description

Detailed Description of the Invention

FIELD OF THE INVENTION The present invention relates to paging in mobile telecommunication networks, and more particularly to paging mobile stations registered in the mobile telecommunication network.

BACKGROUND OF THE INVENTION In today's mobile telecommunications networks, mobile switching stations in the telecommunications network are known.
The incoming call is notified to the mobile station currently registered in the communication network by the paging message transmitted from the center: MSC) via the base transceiver station (BTS) on the paging channel (broadcast paging channel). . Similarly,
The incoming paging message (broadcast paging message) informs the mobile station of the incoming text message (and other network notification messages).

In a typical digital mobile communication network, a BTS located at the center of each geographical cell has to communicate with mobile stations in the geographical cell. Each pair of adjacent BTSs is classified into each location area (LA). European GSM
In a communication network, BTS of a predetermined LA is controlled by a base station controller (BSC).
The visitor location register (VLR) holds not only the record of the mobile station currently registered in the communication network but also the LA in which each registered mobile station is currently located. This information is updated as each registered mobile station roams between LAs. Each VLR is typically co-located with the MSC of the communication network. In Japan's PDC communication network, since the role of BSC is integrated with MSC called Visited MSC (Visited MSC), it is VMSC that holds and updates LA information.

When the PDC type communication network, which is a Japanese digital standard, is further examined, one call channel is assigned to each LA, and a call message is broadcast to mobile stations in the LA on this call channel. be able to. The capacity of one call channel of the PDC communication network is 15 (15 pages) calls per 0.72 seconds.
During peak hours of usage of multiple LAs with relatively large numbers of people (eg, sports stadiums, exhibition venues, etc.), the capacity provided by one paging channel may be insufficient. In such a situation, the incoming call may not be connected to the mobile station as well as the delay in delivering the text message or other message.

Similar call channel overloading may occur after a failure of the VMSC or a component of the VMSC. Such a failure in the PDC communication network may result in loss of information identifying the LA in which the mobile station currently registered in the communication network is located. This is
When the VMSC recovers, it means that the mobile station that has received the incoming call or message alert has been called across the network (ie, for every one of all LAs). ing. This greatly increases the number of call messages that must be sent during the post recovery time. Further, in such a situation, the incoming call may not be connected to the mobile station, and the incoming message may not be delivered. Also, the PDC that the Home Location Register (HLR) holds at the MSC level (as opposed to the LA level) holds details about the subscriber location of the network.
Loss of LA information can occur if the home location register (HLR) of the network fails. When the failed HLR resets, its momentum is VMS
When it reaches C (Reset ... has a knock-on effect on VMSCs), the LA information of the VMSC disappears.

A similar problem is that mobile telecommunications networks other than PDC networks, such as GSM, AMPS and TA.
It can also occur in the CS communication network.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome, or at least mitigate, the above mentioned shortcomings with existing mobile telecommunication networks and calling systems. This and other objectives are achieved by providing a mechanism by which incoming calls and notifications can be prioritized to ensure optimal use of paging messages.

According to a first aspect of the present invention, there is provided a method of processing incoming calls and call alerts (message alerts) at a control center of a mobile communication network during times of high call demand. The method comprises: receiving at the control center the alert signals, identifying a priority level of each call signal, a call message corresponding to at least a fraction of the alerts. (Paging message) is broadcast to each mobile station registered in the communication network. In this method, a paging message corresponding to a paging signal having a high priority level has a low priority level. It is broadcast before the call message corresponding to the call signal.

In one embodiment of the present invention, the priority level of the alert signal is determined depending on the service associated with the alert signal. For example, the ringing signal may be associated with a voice or fax telephone call, a data call, a text message, a network notification message, and the like. More specifically, the priority level of the paging signal may be related to the temporal urgency of the service associated with the paging signal. This means, for example, that ringing signals for telephone calls are assigned the highest priority and ringing signals for text message delivery are assigned the lowest priority. Therefore, the call channel (
If a paging channel) is in use, ringing signals related to the delivery of text messages are rejected, while ringing signals for incoming calls on the phone are processed immediately or capacity is available on the ringing channel. When placed in a queue to be processed.

It will be appreciated that the paging message is broadcast over the air interface from one or more points remote from the control center. Receiving a plurality of paging signals and identifying the priority level of each paging signal is performed at one node of the telecommunication network, while broadcasting the paging message is at another node of the telecommunication network. It will also be appreciated that it can be implemented in a node.

In another embodiment of the present invention, priorities are assigned based on the calling and / or called party identities associated with incoming alerts. For example, a subscriber of a mobile communication network may select one of several service levels whose subscriber's tariff is linked to the selected service level. If the paging channel is in use, the ringing signal associated with the subscriber (either the calling party, the called party, or a combination of both) that has selected the highest level of priority will be subscribed to the lower service level. It is processed before a call signal associated with a person and processed as a call request.

In order to identify the priority of the calling signal based on the identity of the calling party, the control center has a category of incoming trunk to the center, a telephone number string of the calling subscriber, and , The prefix dialed before the called B-number (pr
efix), or one of.

In order to identify the priority of the calling signal based on the identity of the called party, the control center may call the telephone number (B number) string or the IMSI number string of the called party, and You can look up one of the prefixes dialed before the B number.

Identification of the priority level associated with a given calling or called party is maintained from the control point to some other network node, eg, the priority level of the subscriber. Is determined by sending an inquiry to the service control point of the HLR or intelligent network that is

The control center that receives the incoming call signal and broadcasts the call message is a PD
It may be VMSC in the C communication network or the AMPS communication network.

In the GSM network, the control center may be MSC-VLR or BSC. In GSM networks, call priorities are enhanced Multi-Level Precedence and Pre-emption (eMLPP) service (ETS).
Given or retrieved from 300 932). The BSC may indicate to the MSC-VLR the congestion level of the call in the relevant location area by sending a paging congestion message to the MSC-VLR. Upon receiving this message, the MSC-VLR filters out low priority call signals and removes them, and informs the BSC of only high priority call signals. In this way, signaling traffic between MSC-VLR and BSC can be reduced.

In the case of a system where the call function is shared between the MSC-VLR and the BSC, the MSC-VLR not only sends the priority level to the BSC with the call request, but also the MSC-VLR wait indicator (queuing). indicator) can be sent. This indicator indicates whether the BSC can add a call request to the queue.
Notify BSC.

The call priority is determined by the type of call requested by the call signal. For example, if a call signal requests a global page (that is, a call for all LAs controlled by the control center), this call signal is given a low priority, while the call signal is local. When requesting a call (ie, a call for one LA), the call signal is given high priority.

According to a second aspect of the present invention, there is provided a call control system for a mobile communication network, the system comprising an input means for receiving a call signal corresponding to an incoming call and an incoming message, and at least It has a processing means for identifying the priority level of the incoming call signal during a high call request time, and a transmitting means for transmitting a call message corresponding to the call signal via the call channel of the communication network. When the amount of incoming call signals is large, the sending means sends a call message corresponding to a call signal with a high priority,
It is arranged to be broadcast before the call message corresponding to the low priority call signal.

Detailed Description of an Embodiment A telecommunications network 1 utilizing the Japanese PDC digital mobile telephone standard is shown in FIG. The network includes a number of base transceiver stations (BTS) 2, each of which is a mobile station (MS) located in a geographical cell centered on the BTS 2.
It is arranged so that it can communicate with 3. A pair of adjacent BTSs 2 that cover an area 5 called a location area is a visited mobile service switching center (Visited).
It is collectively controlled by the Mobile Services Switching Center (VMSC) 7. The VMSC 7 is responsible for controlling multiple LAs and for routing telephone calls, other users and signaling data within the telecommunication network 1. In the PDC system, the VMSC 7 holds the record of the MS currently registered in the communication network 1 as well as the LA in which the registered mobile station is located (This role in the GSM communication network is the visitor location register. (VLR) performed).

The mobile communication network 1 is called the mobile communication network 1 and its mobile communication network (foreign mobile net).
at least one gateway MSC (G
MSC) 8. Examples of other communication networks are the PSTN communication network 9 and the mobile communication network 10.

When a subscriber (either the PSTN communication network 9 or another mobile communication network 10) makes a voice call to the MS 3 currently registered in the mobile communication network 1, the ISDN user section (ISDN)
User Part: ISUP) protocol, using the sender's home communication network 9 or 10
To the VMSC7 of the mobile communication network 1 from the initial address message (Initial Address Me
ssage: IAM) will be sent. The IAM contains a field that identifies the IAM associated with the voice telephone call. Normally, VMSC7 looks up MS3's record and calls the called LA's current LA.
Responds to the reception of IAM by identifying. The VMSC 7 then broadcasts the paging message from the identified BTS 2 of the LA on the paging channel assigned to that LA.

Generally, the paging message broadcast includes the International Mobile Subscriber Identity (IMSI) of the called MS3. MS3 ’s own
To know the IMSI, it responds to the paging message by listening to the broadcast channel and returning an acknowledgment message to its mobile network 1. After this, the resources of the air interface are reserved and the B-number reply message is propagated to the originator's network to establish a circuit-switched link to carry the voice data.

For example, the mobile communication network or its own mobile communication network (home mobile network)
From MS registered in any of 1 (short message service (SM
When a text message (called S) is received at the VMSC 7, this message is first sent to the message center (MC) 11 of the home network 1. The MC 11 then sends an IAM to the VMSC 7 to indicate that there is an incoming text message. Similar to a call signal for a voice call, the VMSC 7 broadcasts a call message to the destination MS3, assuming capacity is available on the call channel assigned to the LA where the destination MS3 is located. In the GSM communication network, the MAP message "Forward SM (Fo
rwardSM) ”can be used to send an alert from the MC to the MSC-VLR.

As already explained above, in order for one paging channel to handle (either due to low demand, failure of VMSC 7 and loss of location information), the amount of incoming paging signals is It can be too big. The VMSC 7 is aware of the amount of call signaling alert traffic (ie, incoming IAM) and, in the event of overload, identifies the priority level of each call signal. Time is important (time-cri
tical) ringing signals are assigned a high priority and time-insensitive ringing signals are assigned a low priority. Therefore, the ringing signal corresponding to the incoming call of the telephone to the MS3 is assigned a high priority and the incoming notification indicating the incoming text message is assigned a low priority. The VMSC 7 of the communication network 1 immediately broadcasts a call message on a call channel of an appropriate LA for a call signal of high priority. In contrast, text messages (
And other low-priority services) will be sent to the call message only when spare capacity is available on the call channel and when no time-sensitive related call signals are waiting in VMSC7. To be converted. In some circumstances, the VMSC 7 may return an error message to the originator, eg, MC 11, if the call message cannot be broadcast for a low priority call signal. The originator can later try to initiate the connection, or even refuse the operation.

It will be appreciated that other types of ringing signals may be given high or low priority levels, or some intermediate level of priority. These call signals include message waiting indication (Message Waiting Indica) along with call signals for fax calls and data calls.
option: MWI).

In an alternative embodiment of the invention, a network operator may require a subscriber to select one of several service levels. For example, the subscriber
One may choose a high priority delivery service or one may choose a low priority delivery service. In an environment with high call traffic, an outgoing call for a subscriber who chooses a high priority delivery service is called before a subscriber who chooses a low priority delivery service. Of course, operators add premiums to the high-priority delivery service and / or discount subscribers who choose the low-priority delivery service. When a call is placed or a text message is sent to a subscriber of another network, the IAM can include an indication of the delivery priority selected, which indication is detected on the other VMSC.

The VMSC 7 of the communication network 1 from which the call or text message distribution is started can hold the subscriber's register together with the selected distribution service. The priority of the calling subscriber is determined based on the category of the incoming trunk line to the exchange or the telephone number of the calling subscriber. Priority is also identified based on the number prefixed to the called party number (B number). The priority of the caller is determined from the incoming signaling message, eg ISUP signaling parameters.

It will be appreciated that the level of delivery service is based on the identity of the called party. The called party category is retrieved from the HLR or SCP, or the called party's telephone or IMSI number sequence.

As already explained, the present invention can be applied to a GSM communication network, but in the GSM communication network, the MSC-VLR generates a call request based on a call signal (incoming alerts), These call requests are sent to the BSC associated with the given location area. If there is no information on the level of call congestion in BSC, MSC-VLR will
All call requests must be sent to the BSC. In order to reduce the level of signaling traffic between the MSC-VLR and the BSC, the BS processing this traffic
New parameters may be added to SAP. This parameter indicates the level of congestion at the BSC, and more specifically notifies the MSC-VLR when the BSC's call channel is congested. After this, the MSC-VLR selects and removes the low-priority ringing signal, and only BSCs the general call request corresponding to the high-priority ringing signal.
To notify.

In the GSM network, an additional parameter, referred to here as the “queue indicator”, is M
It may accompany the call request sent from the SC-VLR to the BSC. This indicator indicates to the BSC whether the call request is placed in the BSC's call queue and waiting to be broadcast on the call channel. When a new call request is received at the BSC and the call channel is congested, the associated queue indicator is examined to determine if the call request can be added to the queue. If so, the request is queued. If the request cannot be queued, the BSC analyzes the priority level associated with the request. If the priority level is high, the BSC can reject lower priority requests in front of or near the call request and replace them with new requests. If the newly received request has a low priority, the request is rejected without being queued. These queue indicators can be added to the use of call channel congestion parameters, as described in the preceding paragraph.

It will be understood by those skilled in the art that various modifications can be made to the above-described embodiments without departing from the scope of the present invention. For example, it was pointed out that the present invention is applicable to GSM communication networks. In this case, the priority of the ringing signal is MS
Determined at C-VLR level or SCP level. The paging message is sent to the appropriate BSC along with the message priority. Knowing the available call capacity, the BSC can decide whether to broadcast this call message.

Although the embodiments described above utilize circuit switched calls, it will be appreciated that the invention may be conveniently used in packet switched networks such as GRPS and the proposed UMTS. . The present invention is not limited to the above-mentioned protocol for carrying call signals to the VMSC / MSC-VLR. For example, TCP / IP can be used to carry the call signal.

[Brief description of drawings]

[Figure 1]   The figure which shows the PDC type communication network typically.

2 is a flowchart showing a method of processing a call message in VMSC of the communication network of FIG.

[Procedure for Amendment] Submission for translation of Article 34 Amendment of Patent Cooperation Treaty

[Submission date] June 5, 2001 (2001.6.5)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Contents of correction]

[Claims]

2. The method of claim 1 , wherein the level of priority given to a service depends on the time-criticality of the service.

3. A method according to claim 1 or claim 2 , wherein the service comprises voice, data or fax calls and text messages, the latter being given a relatively low delivery priority and the former being compared. The method wherein the highest delivery priority is given.

4. The method of claim 1, wherein a priority level is assigned based on the identity of the calling and / or called party associated with an incoming call signal.

5. The method according to claim 1, wherein the priority assigned to the paging signal is paging resources occupied by the paging signal.
The method depending on the amount of.

6. The method of claim 5 , wherein call signals that are global calls are given low priority, and call signals that are local calls are given high priority.

7. A method as claimed in any one of claims 6, wherein the communication network is a PDC communication network, the control center receives an incoming call signal broadcasting a paging message , The method being VMSC.

8. A method as claimed in any one of claims 6, wherein the communication network is a GSM network, the control center receives an incoming call signal broadcasting a paging message , MSC-VLR or BSC.

9. The method of claim 8, by sending a call congestion message to the MSC-VLR, the BSC is, when indicating the level of call congestion level associated location area MSC-VLR, said MSC -The VLR selects and removes low priority call signals and notifies the BSC of only high priority call signals.

10. The method according to claim 8 or 9 , wherein the MSC-
The VLR sends a queue indicator to the BSC along with a call request to the BSC for the BSC to broadcast a call message, and the queue indicator allows the BSC to add the call request to the queue. The method of notifying the BSC whether or not.

11. The method as claimed in any one of claims 6, wherein the control center, the method is a service control point.

12. A call control system for a mobile communication network, comprising: input means for receiving a call signal corresponding to an incoming call and an incoming message; and priority of an incoming call signal at least during a time when demand for the call is high. A processing means for identifying the level of ranking, and a transmitting means for transmitting a calling message corresponding to the calling signal via the calling channel of the communication network, wherein the priority is high when the amount of the incoming calling signal is large. paging message corresponding to the call signal, in a system that includes, said transmitting means being arranged to be broadcast before the call message corresponding to the low priority call signal, said processing means, said call signal by assigning the identification of services and priorities accordingly associated, It said system characterized by being arranged to identify the priority level of the call signal.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Contents of correction]

A similar problem is that mobile telecommunications networks other than PDC networks, such as GSM, AMPS and TA.
It can also occur in the CS communication network. U.S. Pat.No. 5,533,094 refers to mobile stations in a cellular telecommunications system.
It explains how to put it out. Call priority, based on the pattern of the previously characteristics of the allocated group and calls assigned to each call.

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Contents of correction]

[Figure 1]

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Claims (13)

[Claims] 1. A method of processing an incoming call and an incoming call signal at a control center of a mobile communication network during a time when a demand for the call is high, wherein the control center receives the call signal and each call. Identifying the priority level of the signal, and broadcasting a paging message corresponding to at least a part of the paging signal to each mobile station registered in the communication network, The method wherein the paging message corresponding to a higher level paging signal is broadcast before the paging message corresponding to a lower priority paging signal. 2. The method of claim 1, wherein the priority level of a paging signal depends on a service associated with the paging signal. 3. The method according to claim 1, wherein the level of priority given to the service is time-criticality of the service.
) Said method depending on. 4. A method according to claim 2 or claim 3, wherein the service comprises voice, data or fax calls and text messages, the latter being given a relatively low delivery priority and the former being compared. The method wherein the highest delivery priority is given. 5. The method of claim 1, wherein a priority level is assigned based on the identity of the calling and / or called party associated with an incoming call signal. 6. The method according to claim 1, wherein the priority level assigned to the calling signal is a calling resource (Paging res) occupied by the calling signal.
The method according to the amount of ources). 7. The method of claim 6, wherein call signals that are global calls are given low priority and call signals that are local calls are given high priority. 8. The method according to any one of claims 1 to 7, wherein the communication network is a PDC communication network, and the control center that receives an incoming call signal and broadcasts a call message. , The method being VMSC. 9. The method according to any one of claims 1 to 7, wherein the communication network is a GSM communication network, and the control center that receives an incoming call signal and broadcasts a call message. , MSC-VLR or BSC. 10. The method of claim 9, wherein the BSC indicates to the MSC-VLR the call congestion level of the associated location area by sending a call congestion message to the MSC-VLR. Is a method for selecting and removing low priority call signals and notifying the BSC of only high priority call signals. 11. The method according to claim 9 or 10, wherein the MS
The C-VLR sends a queue indicator to the BSC along with a call request for the BSC to broadcast a call message, the queue indicator allowing the BSC to add the call request to the queue. The method of notifying the BSC whether or not it is possible. 12. The method according to any one of claims 1 to 7, wherein the control center is a service control point. 13. A call control system for a mobile communication network, comprising input means for receiving a call signal corresponding to an incoming call and an incoming message, and prioritizing an incoming call signal at least during a time when the demand for the call is high. A processing means for identifying the level of ranking, and a transmitting means for transmitting a calling message corresponding to the calling signal via the calling channel of the communication network, wherein the priority is high when the amount of the incoming calling signal is large. Said transmitting means arranged such that broadcasting of a paging message corresponding to a paging signal occurs before a paging message corresponding to a paging signal having a lower priority.