AU2003296691A1

AU2003296691A1 - Control of the configuration status of a mobile radio device for a multicast service

Info

Publication number: AU2003296691A1
Application number: AU2003296691A
Authority: AU
Inventors: Norbert Kroth; Jorg Schniedenharn; Alexander Vesely
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2003-01-13
Filing date: 2003-12-19
Publication date: 2004-08-10
Also published as: CN1757245A; WO2004064421A1; BR0317978A; ATE331397T1; EP1584206B1; JP2006513617A; EP1437900A1; EP1584206A1; DE50304005D1

Abstract

A configuration status (CS) to be assumed by a subscriber station after receiving a piece of multicast useful data (MULTICAST INFO) is adjusted. The multicast data is available via radio waves as a service to a group of subscriber stations, of which one or more has access to first (IDLE) or second (CONNECTED) CS. An Independent claim is also included for a device for radio access control between a base station and subscriber stations over an aerial interface in a radiotelephone communications system for carrying out the method of the present invention.

Description

Verification of Translation I, Bryan Rodwell, an employee of Siemens Translation Services, Hyde House, Oldbury, Bracknell, RG12 8FZ, Berkshire, United Kingdom, declare as follows: 1. That I am well acquainted with both the English and German languages, and 2. That the attached document is a true and correct translation made by me to the best of my knowledge and belief of: (a) The PCT specification of International Application No. PCT/EP03/14638 Date J 2-62> S (Signature of translator) (No witness required) PCT/EP03/14638 / 2003P.00237WOAU CONTROL OF THE CONFIGURATION STATUS OF A MOBILE RADIO DEVICE FOR A MULTICAST SERVICE The invention relates to a method for organization of the wireless interface in a radio communication system according to the preamble of Claim 1. Further, the invention relates to a device for radio access control between at least one base station and user stations over a wireless interface in a radio communication system according to the preamble of Claim 7. In radio communication systems information (for example voice, image information, video information, SMS [Short Message Service] or other data) is transmitted with the aid of electromagnetic waves over a wireless interface between transmitting and receiving station (base station or user station). The emission of electromagnetic waves takes place at carrier frequencies within the frequency band provided for the respective system. For the introduced GSM mobile radio system (Global System for Mobile Communication), frequencies of 900, 1800 and 1900 MHz are used. These systems essentially transmit voice, fax and Short Messages (SMS), as well as digital data. For future mobile radio systems with CDMA or TD/CDMA transmission modes, such as for example UMTS (Universal Mobile Telecommunication System) or other third-generation systems, frequencies in the frequency range of approx. 2000 MHz are planned. These third-generation systems are being developed with the aim of providing global radio cover, a wide range of services for data transmission and above all, flexible PCT/EP03/14638 / 2003P00237WOAU 2 administration of the capacity of the wireless interface, which in radio communication systems is the interface with the least resources. In these radio communication systems, above all through the flexible administration of the wireless interface it should be possible for a user station to send and/or receive a large data volume at high speed as required. Access by stations to the shared radio resources of the transmission medium, such as for example time, frequency, output or space, is regulated in these radio communication systems by multiple access (MA) methods. The connection between a base station and a user station takes place over a wireless interface. The base station can operate several radio cells. Usually at least one base station and one device for radio access control (RNC, Radio Network Controller) are components of a base station subsystem (RNS, Radio Network Subsystem). A radio communication system generally comprises several base station subsystems that are connected to a core network (CN). The device for radio access control of the base station subsystem is connected to an access device of the core network. Various methods are known for the addressing of user stations in radio communication systems. Apart from unicast, in which precisely one user station is addressed, the broadcast, in which all user stations within radio range of the transmitting base station are addressed, is found most often. Further, there is the multicast, in which the user stations of a PCT/EP03/14638 / 2003P00237WOAU 3 multicast group are addressed at the same time as the transmission of multicast useful information. Multicast, in which all radio stations within range of a base station are addressed, corresponds to a broadcast. Apart from individual useful information, data is therefore transferred in radio communication systems which is made available to several users. For example, such useful information comprises video streams or other broadcast and/or multicast information. Services for the transfer of useful information, which are not 'only envisaged individually for a single user, but are made available to several users, are summarized in the term MBMS (Multimedia Broadcast/Multimedia Service). Different MBMS services (Multimedia Broadcast/ Multimedia Service) are usually made available by the core network as separate data streams. As a rule, several configuration statuses are accessible to user stations within the radio communication systems. In UMTS, this involves e.g. Idle Mode, and Connected Mode which is divided into the statuses CELLDCH, CELL_FACH, CELLPCH and URAPCH. The object of the invention is to demonstrate a method and a device for radio access control of the kind mentioned at the beginning, which contributes to the efficient organization of the wireless interface in a radio communication system with group-specific services. This object is achieved for the method by a method with the features of Claim 1 and for the device for radio access control by a device with the features of Claim 7.

PCT/EP03/14638 / 2003P00237WOAU 4 The dependent claims relate to advantageous embodiments and developments. In the radio communication system useful information is provided as a service to a group of user stations via radio. At least two different configuration statuses are possible for at least one user station in the group. According to the invention, the device for radio access control makes a decision on which configuration status the at least one user station should adopt after receipt of the useful information based on one or more parameters. A group consists of at least one user station, as a rule, however, of a large number or plurality of user stations. The maximum number of user stations in a group corresponds to the number of user stations of the radio communication system. The radio communication system may therefore comprise user stations in the group and other user stations that, e.g. may belong to other groups, or also exclusively those user stations that belong to the group. The invention is therefore applicable to broadcast and multicast services. The decision about the type of configuration status to be adopted affects at least one user station in the group. It may affect any number of group members up to the entirety of the user stations in the group. Decisions with various outcomes may also be-taken for various group members. It is possible that the user stations which are subject to such a decision are determined by a condition or a common parameter, such as e.g. a regional restriction or a contract with the operator of the radio communication system. Inaccessible configuration statuses, physical channels to be PCT/EP03/14638 / 2003P00237WOAU 5 observed or also operating statuses of a user station may for example be involved. In an embodiment of the invention, one parameter or at least one of the parameters, is a parameter of the service. A decision can therefore be made solely on the basis of one or more parameters of a broadcast or multicast service, or also on the basis of a combination of one or more parameters of the service concerned with other parameters such as e.g. traffic usage. Preferably one parameter or at least one of the parameters of the service involves a service priority or a repetition frequency for emission of the service, such as e.g. an emission of useful information at intervals of 5 minutes or a transmission frequency of the service, or a length of useful information of the service, such as, for example, an average length of transmission of the service, or a number of items of useful information such as, for example, a number of data packets which are sent as part of the service, or information about the handling of the service by other devices for radio access control, such as, for example, whether another radio communication system with local crossover also offers the service concerned at the moment, or cost information. With regard to cost information, a decision could be made, for example, about the device for radio access control that for expensive services the user stations subscribing to this service are kept in a configuration status that is relatively expensive for the radio communication system. The same also applies to a service with a high service priority. The device for radio access control can therefore have available a list of parameters of the service such as, for example, a traffic profile of a multicast or a broadcast service. The list PCT/EP03/14638 / 2003P00237WOAU 6 entries are then each taken individually, or in combination with one another or with other parameters form the basis for the decision about the configuration status of one or more user stations. In an embodiment of the invention, at least one of the parameters involves a property of at least one user station. This could be, for example, a prioritization of the user station in the radio communication system or information about the battery or storage battery status of the user station. Advantageously, the accessible configuration statuses may comprise a connected mode and an idle mode. A connected mode is characterized by the fact that in this'configuration status a signaling connection between the user station and the radio network is maintained and the user station was assigned a radio network identification. In idle mode on the other hand, the user station is not known to the device for radio access control. In a development of the invention, at least one of the parameters of a core network connected to the device for radio control or of a device for monitoring and maintenance of the radio communication system was transferred to the device for radio access control. According to the invention, the device for radio access control has a means of making a decision on the basis of one or more parameters about the kind of configuration status to be adopted by the at least one user station after receipt of the useful information. Means and devices for implementation of the method can be provided.

PCT/EPO3/14638 / 2003P00237WOAU 7 The invention is explained hereinafter on the basis of an exemplary embodiment with reference to the' diagrams: Figure 1: a segment of a radio communication system, Figure 2: a flowchart of a method according to the invention. The exemplary embodiment relates to a radio communication system according to the UMTS standard. Figure 1 shows a segment of such a third-generation radio communication system.

This comprises a device RNC for radio access control which is linked to a base station NODE B and a core network CN. The object of the device RNC for radio access control is to control and monitor the base stations connected to it with their respective radio cells. The base station NODE B operates such a radio cell in which the user stations UE1 and UE2 are located. Further the device RNC for radio access control is connected to a device OMC for monitoring, control and maintenance of the radio network. The participants in the respective user stations UEl and UE2 subscribed to a multicast service. In this way, the user stations UEl and UE2 form a group. Additional user stations outside the group defined by the subscription of the participants can remain in the radio cells of the base station, which however are not significant for the explanation of the method according to the invention. Useful information such as, for example, stock market information or videos is sent from the base station NODE B and can be received and decrypted by the user stations UEl and UE2 in the group. User stations apart from the user stations UEl and UE2 in the group cannot decrypt this multicast PCT/EP03/14638 / 2003P00237WOAU 8 information. After activating a user station in the radio communication system, this is in idle mode. This mode is characterized by the fact that this user station is known in the core network CN, but not in the radio access network (RAN) of the radio communication system by means of identification information. A device RNC for radio access control therefore does not know which user stations are in idle mode in the radio cells of the base stations connected to it. A user station in idle mode does not exchange any information with the radio network until a connection request is made by the user station. After such a connection request, the user station changes to connected mode. A connection request may, for example, be initiated by the demand from the user station for a service or also by a paging inquiry from the radio network. The user stations of the radio communication system which are in connected mode are known to the respective device for radio access control on account of identification information and can therefore be located. The corresponding identification information was transmitted to the device for radio access control by the user station. The core network can also transmit information to the device for radio access control via the respective user station. While the connected mode is active, the respective user stations monitor other radio channels than the user stations which are currently in idle mode. A user station may also be in connected mode if it is not currently assigned a physical channel. In the flowchart in Figure 2, the user station is in idle mode IDLE at the beginning. In this mode, the user station cannot receive any useful information for the multicast service. In PCT/EP03/14638 / 2003P00237WOAU 9 order to be able to configure this for receipt of the useful information for the multicast service, it is necessary to notify the user station before transmitting the useful information. This notification takes place by means of a paging channel which the user stations subscribing to the multicast service observe. This notification involves group specific information which is solely addressed to the user stations UEl and UE2 in the group. The user station in Figure 2 receives the information necessary for the receipt and processing of the useful information for the multicast service from the signal PAGING. As a result of this, the user station changes to connected mode CONNECTED as a result of appropriate signal exchange with the base station. In this configuration status the user station receives the useful information MULTICAST INFO for the multicast service. After receipt of the useful information MULTICAST INFO from the multicast service, the user station can either remain in connected mode CONNECTED or switch to idle mode IDLE. In the latter case, a renewed switch -to connected mode CONNECTED is initiated on account of the next paging message which announces useful information for the multicast service. According to the invention, the device for radio access control makes a decision on whether the user station switches to idle mode IDLE or remains in connected mode CONNECTED after receipt of the useful information MULTICAST INFO for the multicast service. The device for radio access control takes this decision with the aid of a traffic profile of the multicast service, which profile was made available to the device for radio access control by the core network after PCT/EP03/14638 / 2003P00237WOAU 10 activation of the service. Alternatively, the traffic profile could also be notified to the device for radio access control per configuration when the multicast service is made available. Therefore the device for radio access control is in a position to decide which configuration status the user stations of the multicast group should adopt between the individual items of multicast information on account of the available traffic profile and the current load situation. This decision may be notified to the user stations in the paging message or in the message for the multicast service or in a'separate signaling message which can be transmitted before or also after the message for the multicast service. The decision on the configuration status to be adopted between the individual items of useful information for the multicast service may be taken both for all the user stations in the group, and also for one or more user stations regardless of the remaining user stations in the group. The decision may also include a combination of parameters of the traffic profile of the multicast service with user-specific parameters. Thus, for example, with regard to a highly prioritized user station, the decision could be taken for this to remain in connected mode while other user stations switch to idle mode. On account of the exchange of signaling information between a user station in connected mode and the respective base station, a user station remaining in connected mode signifies increased usage of the radio communication system. On the other hand, the connected mode offers the possibility that between the receipt of the paging message and the useful PCT/EP03/14638 / 2003P00237WOAU 11 information for the multicast service no time is required for a change in the configuration status, so that real-time data can be transmitted without delay. A further advantage of remaining in connected mode is that in this case the location of the user station is known to the radio network. This knowledge is relevant if the useful information for the multicast service is solely to be broadcast in the radio cells in which user stations in the multicast group are located. The decision of the device for radio access control therefore consists of the consideration of a series of influencing factors. A concrete example of such a decision is considered below: the content of the multicast service consists of information for entertainment offers such as, for example, cinema programs; the device for radio access control is subject to heavy use on account of a large number of user stations in the radio communication system; the multicast service is assigned a low priority in the traffic profile; the multicast service is broadcast at a repetition frequency of 30 minutes. In this case, the device for radio access control decides, for example, to let the user stations switch to idle mode. Otherwise, for example, the decision by the device for radio access control would be omitted if the content of the multicast service consisted of information about the traffic situation such as, for example, congestion messages, currently only a small proportion of the capacity of the device for radio access control were being used, the multicast service was assigned a high priority in the ,traffic profile and useful information for the multicast service were to be transmitted at intervals of 5 minutes. In this case, it would be preferable that at least some group users in the multicast PCT/EP03/14638 / 2003P00237WOAU 12 group remained in connected mode. If the device for radio access control is aware on account of the traffic profile of the multicast service that the service is broadcast very frequently, then, for example, the decision can be taken to keep all user stations in the multicast group in connected mode. This decision may be notified to the user stations concerned directly after subscription to the service. In this case the decision need not be retaken every time the service is broadcast, it is valid for the duration of time over which the service is broadcast. As in the aforementioned case all user stations in the multicast group are in connected mode, the broadcasting of a paging message is unnecessary. On account of the connected mode, the device for radio access control is aware whether user stations in the multicast group are in the area controlled by it.

Claims

1. Method for organization of the wireless interface in a radio communication system with user stations (UEl, UE2) and at least one device (RNC) for radio access control between at least one base station (NODE B) and user stations (UE1, UE2) over a wireless interface, whereby useful information (MULTICAST INFO) is made available as a service to a group of user stations (UEl, UE2) via radio, whereby for at least one user station (UEl, UE2) in the group at least two different configuration statuses (IDLE, CONNECTED) are accessible, c h a r a c t e r i z e d i n t h a t the device (RNC) for radio access control decides on the basis of one or more parameters about the type of configuration status (IDLE, CONNECTED) to be adopted by the at least one user station (UEl, UE2) after receipt of the useful information.

2. Method according to Claim 1, c h a r a c t e r i z e d i n t h a t the one parameter or at least one of the parameters involves a parameter of the service.

3. Method according to Claim 2, c h a r a c t e r i z e d i n t h a t the one parameter or at least one of the parameters involves a service priority or a repetition frequency for emission of the service, or a length of useful information (MULTICAST INFO) of the service or a number of items of useful information (MULTICAST INFO) or information about the handling of the service by other devices for radio access control or cost information. PCT/EPO3/14638 / 2003P00237WOAU 14

4. Method according to one of Claims 1 to 3, c ha r a c t e r i z e d i n t h a t at least one of the parameters involves a property of at least one user station (UEl, UE2).

5. Method according to one of Claims 1 to 4, c ha r a c t e r i z e d i n t h a t in accessible configuration statuses a connected mode (CONNECTED) and an idle mode (IDLE) are involved.

6. Method according to one of Claims 1 to 5, c h a r a c t e r i z e d i n t h a t at least one of the parameters of a core network (CN) connected to the device (RNC) for radio access control or of a device (OMd) for monitoring and maintenance of the radio communication system was transmitted to the device (ENC) for radio access control.

7. Device (RNC) for radio access control between at least one base station (NODE B) and user stations (UE1, UE2) over a wireless interface in a radio communication system, whereby useful information (MULTICAST INFO) is made available as a service to a group of user stations (UE1, UE2) via radio, whereby for at least one user station (UE1, UE2) in the group at least two different configuration statuses (IDLE, CONNECTED) are accessible, c h a r a c t e r i z e d i n t h a t the device (ENC) for radio access control has a means of making a decision on the basis of one or more parameters about the type of configuration status (IDLE, CONNECTED) to be adopted by the at least one user station (UE1, UE2) after receipt of the user information (MULTICAST INFO).