Method, system, transmitter and receiver for multicast messages in a wireless system

A method for transmitting multicast messages in a Radio system and appropriately designed and radio system correspondingly designed transmitter and receiver

The present invention relates to a method for transmitting of multicast messages in a radio system, in particular a mobile radio system, as well as a correspondingly designed Radio system and appropriately designed transmitter and Receiver.

The mobile technology is in a rapid development. Currently, on the standardization of the so-called UMTS mobile radio system ( "Universal Mobile Telecommunication System ") of the third generation mobile phone worked.

As multicast messages Messages are designated, which from a transmitter, for example in a mobile radio system of a base station, simultaneously to a (as multicast group Marked) group of receivers, eg mobile stations, be transmitted, ie, the transmitter sends a multicast message only once to the to the respective multicast group belonging receiver, the transmitter, where appropriate, it is not known which of the of range of the Transmitter located mobile stations to the multicast group and thus be as a receiver for the transmitted multicast message come into question.

While for some time approaches for transfer of such multicast messages in mobile systems are discussed in this regard are still not complete known and satisfactory proposals.

Therefore, the present invention is based on the object, a method for transmitting multicast messages in a Radio system, especially a mobile radio system to suggest which multicast messages with little effort, can be sent securely and reliably. Furthermore should accordingly by means of the present invention ausgestaltetes radio system with an appropriate transmitter and Receivers are provided.

This object is inventively achieved by a method with the features of claim 1 and a radio system with Features of claim 27 and a transmitter as claimed in claim 29 and achieved a receiver according to claim 31st The sub-claims each define preferred and advantageous embodiments of the present invention.

According to the invention, before the transfer of Multicast messages send a message to the assignment or allocation of resources in the radio system, in particular for to transfer assignment of appropriate communication channels, wherein of the belonging to the corresponding multicast group Recipients evaluate this message, and each one of these up communication connection corresponding to the transmitter and is configured to allow for a transfer the multicast messages from the transmitter to the receiver via the previously configured connections can. The multicast messages can be in particular also be irregularly distributed data over time.

With the initially transmitted from the transmitter to release Allocating resources in the radio system are to be the Multicast group belonging receivers preferably Resources a general transport channel and a general physical channel on which the common transport channel is mapped assigned. A "common channel" ( "Common Channel") is a readable by all recipients or understood audible channel, which is thus in contrast to a so-called "Dedicated Channel" no special receiver is assigned.

The allocation for the transferred resources release of Transmitter preferably contains information about the configuration the general transport channel and the common physical Channel, so that the belonging to the multicast group Receiver the common transport channel and the general physical channel in accordance with this notice to prepare for the transmission of multicast messages can configure.

The provided for allocating resources of message Transmitter can in particular a general logic Control or control channel is transmitted and an identifier have for each multicast group, so that the individual recipients by evaluating this identifier to determine whether they to the corresponding Multicast group belong or subsequently transmitted Multicast messages intended for them.

Alternatively, the provided for allocating resources Notice from the transmitter also has a special logic Control or control channel, which is exclusively for the Transmission of control messages or control messages is provided for multicast groups are transmitted.

Once a receiver, ie, in a mobile radio system a Mobile station, wherein the transmitter side, that is, in a mobile radio system at the network operator or the wireless network control unit, has registered for a multicast group, is the receiver from the transmitter side the identifier for notified the respective multicast group.

If a receiver from the transmitter, a communication on the receive presence to be transmitted multicast messages and part of the receiver to a multicast group, is of the Receiver a corresponding multicast unit in the so-called BMC layer ( "Broadcast Multicast Controller") of Receiver, which in a corresponding RLC entity the so-called RLC layer ( "Radio Link Control") of Layer model is connected, configured. This RLC entity preferably via a common data channel with the so-called MAC-layer ( "Medium Access Control") connected, said general data channel to the previously mentioned general transport channel is mapped. when the recipient of the corresponding multicast group logs out, the multicast unit of this receiver is dissolved in the BMC layer again.

Do all belonging to the affected multicast group Receiver built up a signaling connection to the transmitter, can from the transmitter already mentioned above (and hereinafter simply referred to as "resource allocation message" or "resource allocation message" hereinafter) Communication on the allocation of resources of the radio system for Sending preparing the transfer of multicast messages , so that the multicast group to the respective receivers belonging to the common transport channel and the general physical channel in response to the in This release contains configuration information to configure, and then transfer the Multicast messages is possible.

The resources, ie the corresponding general transport channel and the general physical channel, are preferably only assigned for a certain period of time, wherein For example, the start and end time of this time, the individual recipients with the resource allocation message be notified, said after this time this general transport channel and this general physical channel preferably be dismantled.

The present invention is preferably suitable for use in a mobile radio system, in particular in a UMTS mobile radio system. Naturally, however, the present invention is not limited to this preferred application, but can generally be used in any radio system are, in the transmission of multicast messages should be possible, bearing in mind that the present invention, both the transmitter side and the Receiver side are concerned.

The present invention will in more detail below with reference to the accompanying drawings based on preferred embodiments explained.

Fig. 1 shows a simplified illustration of a mobile radio cell a mobile radio system for explaining the invention Transmission of multicast messages,

Fig. 2 shows a state diagram for explaining the transmission of multicast messages in accordance with a preferred Embodiment of the present invention,

Fig. 3 shows a representation of multiple layers of a explained layer model by applying the well with reference to FIG. 2 Embodiment,

Fig. 4 shows a possible design of an inventive Multicast message or resource allocation message,

FIG. 5 shows a representation of a layer model for explaining the transmission according to the invention of multicast messages, and

Fig. 6A and Fig. 6B are views showing a so-called "Physical Shared Allocation Message" prior Technology.

In the present invention, a method for Transmission of multicast messages or to Ressourcenallokierung to prepare for the transmission of multicast messages proposed, this being in particular using a general transport channel and a general physical channel, the different at different times Mobile stations may be assigned to happen. One example is the UMTS mobile radio systems ( "Universal Mobile Telecommunication System ") as" Downlink Shared Channel "(DSCH) designated channel. It is particularly also described how the resources by signaling on a common channel single multicast group are assigned, wherein in the present Invention with "common channel" ( "Common Channel"), a channel is meant the be read by all mobile stations can.

Since the present invention partially in common with an already conventionally used for UMTS mobile radio systems provided and transferred for other purposes resource allocation message, namely the so-called "Physical Shared Channel Allocation Message ", has to follow first the generation and production of conventional are explained in resource allocation message, before the Received special features and details of the present invention becomes.

THE "PHYSICAL SHARED CHANNEL ALLOCATION MESSAGE" UNDER UMTS

The layer model of the protocols on the air interface according to the UMTS mobile radio standard is shown in Fig. 5.

Each mobile station UE consists of a physical layer PL ( "Physical Layer"), the transmitter side for processing the data for transmission over the air interface via physical channels 10 is responsible, and the receiving end the received data as a media access control layer overlying MAC ( "Medium Access Control") passes, that they are further processed by this layer can. On the network side is the physical PL layer in a base station BS which landline connection via a a radio network controller RNC ( "RNC") of the respective mobile radio system connected or wireless service provider. The connections between the physical layer PL and the MAC layer are called transport channels 11 and specify how the data be transferred (eg on general channels or channels, the only dedicated to a particular mobile station are). The MAC layer has tasks such as identification of users for which a packet is intended, if it is transmitted on common channels, and the picture of logical channels 12 onto the transport channels 11. For adds the MAC layer transmitting end control information (for example, the identity of the mobile station) to be transmitted to the Data packets which will them from a radio link control layer RLC ( "Radio Link Control") has received. At the receiving end this control information is analyzed and removed from the data packets, before they are delivered the logical channels 12 forwarded to the RLC layer will. As logical channels 12, the compounds are between the MAC layer and the RLC layer respectively.

The RLC layer is responsible for the monitoring of the Data transmission, ie for the identification of missing data packets and possibly the new request. In the RLC layer, multiple units can be defined. Each RLC entity is a connection between higher Layers and RLC (eg Radio Bearer) connected. Also the RLC layer may transmitter end the data packets it receives from scored higher layers, add control information. This control information is used at the receiving end, to judge as to whether data packets are missing, and removed from the data packets, before they return to the higher layers are passed.

Above the RLC layer is a radio resource control layer RRC ( "Radio Resource Control"), which for the Configuration of the underlying layers and especially their is responsible for establishing the connection. The connections 13 are exchanged between the RLC layer and the RRC layer "Signalling Radio Bearer" (SRB) called. Also located located above the RLC layer radio bearer, called "Radio Bearer ", which are used for the actual data transmission and the connection 14 between the RLC layer and the representing parent application. Transferring the packet data, also located above the RLC layer a so-called packet data convergence layer PDCP ( "Packet Data Convergence Protocol "), for example, for the compression of is IP packets ( "Internet Protocol") responsible. furthermore is located above the RLC layer, a so-called "Broadcast Multicast" -Kontrollschicht BMC ( "Broadcast Multicast Controller ") which so called for the reception of "Cell Broadcast" messages is used. The BMC layer can similarly to the RLC layer several BMC units To be defined.

For transmission in particular packet data was for UMTS already known as a DSCH ( "Downlink Shared Channel") specified. The DSCH is a transport channel 11, the on a physical channel PDSCH ( "Physical Downlink Shared Channel ") is displayed. The special thing about this channel is that a radio network controller RNC resources reservations within a radio cell and the resources for assign a certain amount of time a particular mobile station UE can, so that there is a just this in the specified time a Mobile station UE dedicated resource. This leaves irregularly accruing traffic efficiently Send manner to the mobile station.

In UMTS, two different modes are defined, the TDD - ( "Time Division Duplex "), and the FDD mode (" Frequency Division Duplex "). In the case of TDD mode, the PDSCH resource the RRC layer over the radio network controller RNC a message "Physical Shared Channel Allocation" a mobile station assigned UE, either on a general Channel ( "Common Channel"), the UE from all mobile stations at the same time can be read, or on a channel which only a certain mobile station UE is assigned to the Mobile station is sent. In UMTS, the general Transport channel 11, the multiple mobile stations UE at the same time can be read and on the news from the network to the mobile stations UE can be sent, as FACH ( "Forward Access Channel") called. This general Transport channel 11 in the physical layer PL mapped onto a common physical channel 10, the UMTS as SCCPCH ( "Secondary Common Control Physical Channel ") is referred to. In the event that the message is sent via a common channel, the message contains an identifier for the mobile station for which this Message is intended.

In the context of the present invention is in particular the transfer the RRC message "Physical Shared Channel Allocation Message "on general channels of interest. Therefore, is mainly considered this case in the following.

Furthermore, the transmission of the above, in this case said message be divided into two sub-cases.

In the first case, the RRC message "Physical Shared Channel Allocation Message "to Ressourcenallokierung in Radio network controller RNC via a only a certain Mobile station UE allocated logical channel 12 of if the RLC layer to the MAC layer, and in the mobile station UE assigned via such only the mobile station logical channel of the MAC layer to the RLC layer passed. Such only a mobile station UE assigned logical channel 12 is in UMTS as DCCH ( "Dedicated Control Channel") called. The RLC layer in the radio network controller RNC can the message add control information before this one is then passed to the MAC layer. As to the general Transport channel (FACH) and data for other mobile stations transmitted, adds the MAC layer in the radio network controller RNC always certain control information added to a message when the MAC layer this over the DCCH received from the RLC layer and on should forward the general FACH transport channel. With Use the control information, the MAC layers in identify the mobile stations, among other things, whether the message is intended for them.

The control information comprises for, as shown in Fig. 6A among other things, from a field UEIDTYPE which indicates as the ID of the mobile station looks like, and a Field UEID that the actual identification of the respective Mobile station contains. Further comprise the MAC control information a field TCTF ( "Target Channel Type Field ") and a MUX field. The control information TCTF indicates the process via which logical channel a data packet, forwarded that to a common transport channel (FACH) is to be, was given to the MAC layer. This is necessary as the control information, the data packet to the be added to the transmitter side, depending on which logical channel via a common transport channel forwarded data packets originate, are different. When the information is thus included in the TCTF field that the package via a logical DCCH channel to the MAC layer was given, know the receiving mobile station that the Control information from the fields described above is. The MUX field is used for demultiplexing, if several logical channels on each common transport channel be ready. In addition, the message contains a Data packet DP with the actual message information, which has received the MAC layer of the RLC layer, ie the data packet includes a RRC message and possibly added RLC control information.

The message shown in Fig. 6A is thus connected via the respective common transport channel (FACH) 11 to the physical Layer PL passed, which at the news a general physical channel (SCCPH) 10 to all mobile stations UE transmits in the cell signaling compound is a up to the radio network controller RNC have. The configuration of the general transport channel 11 and 10 of the physical channel and the logical Channel (DCCH) 12 and the RLC layer, the MAC layer and the physical layer PL is all mobile stations Build the signaling connection has been made known, that all mobile stations can receive the message. The MAC layers of the mobile stations then check the identity the mobile station for which the message was sent. The mobile stations that do not have the specified in field UEID Identity are identified, discard the message. The mobile station identified by the identity is removed, the MAC control information from the message and outputs the remaining message via the corresponding logical channel (DCCH) 12 next to the RLC layer, which also evaluates the RLC control information and the message packet then passes it to the RRC layer.

In the second case, the RRC layer of the RRC message "Physical adds Shared Channel Allocation Message "itself an information added, identified with that mobile station is provided for this message. The message is forwarded to the RLC layer of the message possibly adds RLC control information and this data packet then a general logical channel (SHCCH = "Shared Channel Control Channel") 12 to the MAC layer passes. The MAC layer adds all the data packets, it has a logical channel (SHCCH) received 12, specific MAC control information added. These consist as shown in Fig. 6B only from the field TCTF, which in this is assigned the value "SHCCH" case. The data packet is then through a common transport channel (FACH) 11 passed to the physical layer PL, which the Message on a general physical channel (SCCPH) 10 transmits over the air interface. The configuration of the general transport channel 11 and the general physical Channel 10, and the logical channel (SHCCH) 12 and RLC layer, the MAC layer and the physical layer PL is again all mobile stations build the signaling link been made known, so that all mobile stations can receive the message. The mobile stations within the cell, the message provide information on the MAC layer and RLC layer to the RRC layer further. The MAC layers the mobile stations remove the MAC control information and forward the message on the basis of contained in TCTF field information on the corresponding logical channel (SHCCH) 12 next to the RLC layer. There the RLC control information to be removed and the message passed to the RRC layer. Only in the RRC layer is based on the information contained in the message checked, sent the message for which mobile station has been. Only the mobile station via the attached identity is identified using the message. All other mobile stations discard the message.

In both cases described contains the PDSCH message Information about, for example, the period in which the Mobile station the PDSCH resources are available, and the configuration of the physical channel 10. Alternatively, can select one or multiple configurations of the PDSCH channel using the system information in the whole cell are distributed and in the message for allocating the PDSCH resources only with an identifier on the appropriate Configuration are referenced. In the event that the message a only a mobile station assigned channel takes place (hereafter "Dedicated Channel" (DCH) hereinafter), reads only that mobile station, the message for which this was also determined.

In the case of FDD mode, the resource allocation is carried out via one only of each mobile station assigned channel ( "Dedicated Channel"). This channel is about a particular Field ( "Transport Format Combination Identifier" TFCI) notified to the mobile station, that in the next time window or frames ( "frame") data for the mobile station on the PDSCH channel is transmitted. The TFCI field are the different transport formats relating to the size and Number of data packets of different logical Ducts 12, so the channels between the RLC layer and the MAC layer, within such a time window, are transmitted, respectively. If a specific assignment uses the TFCI field, the mobile station detects it, that in the next time slot transmission on the PDSCH channel takes place. The configuration of the PDSCH channel was doing communicated in setting up the communication link of the mobile station.

With regard to the RRC layer is between different RRC states differed. The PDSCH channel and DSCH are in TDD mode only in the RRC states CELL_FACH and CELL_DCH, in FDD mode even only in the RRC state CELL_DCH available. In the states CELL_PCH and URA_PCH and IDLE MODE the DSCH / PDSCH channel unavailable.

The various states express, the level at which Position of the mobile station is known and what resources each available.

In the RRC state CELL_DCH of the mobile station are dedicated resources assigned, and the mobile station is at the cell level known, that the network is known, in which cell the respective mobile station is located.

In the RRC state CELL_FACH the mobile station are general assigned resources it with other mobile stations have to share. In this state, the mobile station is also known at the cellular level.

In RRC state CELL_PCH the mobile station receives radio messages from the network and listen to the notification channels PICH ( "Paging Indicator Channel") and PCH ( "Paging Channel"), on the network of the mobile station may be notified that eg messages for each mobile station are present. The mobile station is known in the state at the cellular level.

The RRC state URA_PCH is similar to CELL_PCH, but with the difference that the position of the mobile station Network is exactly not known, but the network only Success has been in what group of cells the mobile station could stop.

In IDLE MODE, the mobile station also receives radio messages from the network and listen to the notification channels PICH and PCH. In contrast to the states URA_PCH and However Cell_PCH has the radio network controller RNC does not Knowledge about the mobile station itself, and not about whether the mobile station is in one of its control Cells is.

The notification mechanism consists of two stages. in the first step divides the network of the mobile station by a Indicator with on the PICH channel that messages on available to the PCH channel for the mobile station. Only then reads the mobile station receives the PCH channel, in which the actual notification is from.

THE TRANSMISSION OF MULTICAST MESSAGE OF THE PRESENT INVENTION

Based on the in connection with the message "Physical Shared Channel Allocation Message "principle described is in the context of the present invention a transmission of Multicast messages in a radio system, in particular a Mobile communication system, is proposed. Ideally, the multicast messages within a radio cell only once a plurality of mobile stations are transmitted simultaneously. The to transmitted data can irregularly over time be distributed, so that transmission over a DSCH channel similar channel would be advantageous.

An essential component of this is the allocation of resources a general transport channel 11 and a general physical channel 10 for transmission of multicast messages, similar to the existing UMTS channels DSCH / PDSCH. This is done in particular by a resource allocation message, which in the following as "multicast Channel Allocation Message "is referred to and the configuration the general transport channel 11 and the general physical channel 10 contains. Alternatively, it may also be possible configurations along with identifiers distribute all mobile stations within a cell and in the resource allocation message to a group of mobile stations only the respective identifier for selection the desired configuration to send. Furthermore, should the Message advantageously information about the Start contain time and end time of a period in which the respective Resource of the group of mobile stations, that is, the Multicast group is assigned.

The resource allocation message "Multicast Channel Allocation Message "may be on two different paths to all mobile stations UE are sent in a cell signaling compound is a the radio network controller RNC have built.

In the first case, the resource allocation message will be a general logical control channel in UMTS as the SHCCH-channel transmitted and includes an identifier for the respective multicast group. The RRC layers of the mobile stations UE each determine whether the message corresponding to the Mobile station is intended or not.

In the second case, the resource allocation message will be a new, specific logical control channel, the only the transmission of control messages for multicast groups to be used, transferred. This special logical channel is hereinafter referred to as MCCCH channel ( "Multicast Control Channel "), respectively. In this case, the MAC layer forms the radio network controller RNC logic MCCCH channel onto a common transport channel 11th at Using the general FACH transport channel 11 adds the MAC layer of the message the control information added TCTF and assigns control information to the value "MCCCH". also adds the MAC layer of the message a further control information MCID, which identifies the multicast group, for which the "Multicast Channel Allocation Message" is determined, added. The entire message with the "Multicast Channel Allocation Message "including any RLC control information (Numeral DP), the TCTF field and the MCID field is shown in Fig. 4 and by the reference numeral SN provided. Advantageously, only the rich MAC layers that mobile station UE that led to the by MCID field designated multicast group include that message to the RLC layer on.

In the event that the mobile stations UE in the IDLE state MODE or in connection state to the RRC states URA_PCH or CELL_PCH are, is in a Benachrichtungs alert which is sent to the mobile stations, as the reason for notifying the presence of multicast messages indicated. In particular, already are existing messages "Paging Type 1" or "Paging Type 2" is used and the Reason for notification by this message in a Information Element "Paging Cause" specified by this Information Element Another value "multicast message" will be added.

A mobile station UE belonging to a multicast group, configure at least one multicast unit in the BMC layer, which connected to an RLC entity in the RLC layer is. The RLC entity is also a general Data channel (CTCH) is connected to the MAC layer. For data transmission is also the CTCH channel in the MAC layer on a common transport channel 11 for transmission of multicast messages ready, said general transport channel 11 in the physical layer PL to a general physical channel is mapped 10th After all Mobile stations UE to the respective multicast group the quantities for which messages for transmission, include, a signaling connection to the radio network control unit RNC have built, this sends the resource allocation message "Multicast Channel Allocation Message". Which logical channel 12 (DCCH or MCCCH) used for is to be, will build the signaling link the mobile stations UE notified. Those mobile stations UE that belong to the corresponding multicast group, build then the common transport channel 11 and the general physical channel 10 for transferring Multicast messages according to the resource allocation message specified configuration.

The functionality described above can also serve as state diagram being represented. The state diagram is shown in Fig. 2, where each state 100-103 follows can be characterized:

In state 100, which are also referred to as "MC_Null" may include the respective mobile station no multicast group and the network does not attempt Accordingly, the mobile station to notify you if a multicast message present for transmission.

In a state 101, which also referred to as "MC_Saving" can be heard each mobile station of a multicast group to which a corresponding multicast unit in the BMC layer exists. The mobile station managed by the State 100 to the state 101 by the mobile station logs for a first multicast group the network, the network then the mobile station an identifier for each multicast group notifies (state transition 1 in Fig. 2). In the state 101, the mobile station reads radio messages and also listen to the notification channels PICH and PCH. The network notifies the mobile station via the notification channels PICH and PCH if multicast messages available for transfer. The state 101 corresponds to the RRC IDLE MODE, CELL_PCH and URA_PCH. A return to state 100 occurs when the mobile station logs out of all the multicast groups and the corresponding Multicast unit is deleted in the BMC layer (State transition 2).

Receives the mobile station a notification that multicast messages to the corresponding multicast group, which belongs to the mobile station exist, the mobile station builds a signaling connection to the network on and changes to a state 102 (state transition 3).

In the state 102, which also referred to as "MC_Monitoring" can be, therefore, the mobile station belongs to a multicast group on, there is a multicast unit in the BMC layer, and there is a signaling connection between the mobile station and the radio network controller RNC, wherein the mobile station at any time RRC messages on a general channel (eg the general FACH transport channel) can receive. This state corresponds to the 102 RRC state CELL_DCH or CELL_FACH. This requires the mobile station be extended over the prior art in such a way that even then always receive a common channel can be when the mobile station is in the RRC state CELL_DCH is.

The mobile station then receives network resource allocation message, with which the resources of a general transport channel and a common physical Channel of the mobile station for the transmission of multicast messages be assigned to. The mobile station establishes the general Transport channel and the general physical Channel to receive multicast messages on and changes in a state 103 (state transition 4).

In the state 103, which is also referred to as "MC_Active" can be, therefore, the mobile station belongs to a multicast group on, there is a multicast unit in the BMC layer, and the mobile station has a common transport channel and a physical channel for the transmission of constructed multicast messages. In addition, the multicast unit connected to an RLC entity in the RLC layer, wherein the RLC entity has a general logical data channel (CTCH channel) is connected to the MAC layer. Of the general logical data channel to the common transport channel ready for the transmission of multicast messages. The mobile station may now multicast messages via These common transport channel and the general physical Channel received. The messages are sent via the general logical data channel (CTCH) to the appropriate RLC entity and from the latter to the multicast unit in the BMC layer forwarded. The multicast unit in the BMC layer uses a contained in the multicast message Multicast address to a corresponding application, the message forward.

After the specified in the resource allocation message Period builds the mobile station to the transmission provided by multicast messages common transport channel and general physical channel off again. Remains the signaling connection between the mobile station and the network initially made, a return in the state 102 (state transition 5). If, however, the Signaling connection between the mobile station and the Network degraded, a return is made to state 101 (State transition 6). A change from the state 101 in the State 103 occurs when the network of the mobile station notifies to transition to the RRC state CELL_PCH.

Below is the generally explained above procedure detail using a preferred embodiment and Referring to FIG. 1 and FIG. Will be explained in the third

Fig. 1 shows the structure of a radio network, as for example specified for the UMTS mobile radio standard. Several mobile stations UE1-5 located in a radio cell Z, which is spanned by a base station BS and which the mobile stations connected via air interfaces are and communicate. The base station BS is in turn a landline connection to a radio network controller RNC connected. It is assumed that the mobile stations UE1-3 belong to a multicast group A, while the Mobile stations UE 4 and UE5 according to this embodiment belong to any multicast group. These are mobile stations thus in the multicast state 100 (see. FIG. 2).

It is also assumed that the mobile station UE1 in the RRC state IDLE MODE and the mobile station UE2 in the RRC state CELL_PCH is. The mobile stations UE1 and UE2 are thus the multicast state 101 (see. FIG. 2) and have constructed accordingly a multicast unit MCU in the BMC layer (See. Fig. 3) with the overlying applications V1 via a connection and via a further connection V2 with a RLC entity RLCU (see. Fig. 3) the RLC layer connected is. The RLC entity RLCU is again a general logical data channel 12 (eg, the CTCH channel) the MAC layer is connected. There is in this state, no general transport channel and not a general physical channel for transmission of multicast messages. The mobile stations UE1 and UE2 listen to the Benachrichtungskanäle PICH and PCH.

The mobile station UE3 is in accordance with this embodiment, are in the RRC state CELL_FACH, ie the mobile station UE3 has a signaling connection to the radio network controller constructed RNC and can signaling messages receive. The mobile station UE3 is therefore in the multicast state 102. The mobile station also has a Multicast unit MCU built in the BMC layer. This is with the overlying applications with a compound V1 and via a further connection V2 with a RLC entity connected RLCU the RLC layer. The RLC entity is in turn a general logical data channel 12 with the MAC layer connected. There is also in this state no general transport channel 11 and no general physical channel 10 for transmission of multicast messages.

The signaling link over which a mobile station resource allocation message "Multicast Channel Allocation Message "receives, can in two different ways be configured. In both cases, the signaling connection so constructed that the message over a general physical channel 10 (eg, the SCCPCH channel) to the physical layer PL reaches, where they generally have a Transport channel 11 (eg, the FACH) to the MAC layer is passed. In the first case (case A), the Message on a general logical control channel 12 (Eg, the channel SHCCH) forwarded to the RLC layer, which eventually passes the message to the RRC layer. Only the RRC layer then checks with reference to the information about the multicast group for which this message has been sent, if the message for the own mobile station is relevant or not. checking in the second case (case B) the MAC layer using the MAC control information, the specify which multicast group determines the message is whether the message for each mobile station determines or not. Subsequently, the MAC layer is the message via a logical control channel 12 (ie, the previously MCCCH mentioned specific channel) to the RLC layer on, said on this logical control channel 12 for news are passed, the determined for this mobile station are. The RLC layer then passes the message to the RRC layer continue.

It is now assumed that a message for the multicast group A arrives at the radio network controller RNC. The radio network controller RNC knows that the mobile stations UE2 and UE3 are in cells of itself be controlled. In addition, the radio network controller know RNC that these belong to the multicast group A. Since the mobile station UE1 in the RRC IDLE state MODE is, the exact cell in which the mobile station UE1 is, the radio network controller RNC does not known. Therefore, the radio network controller RNC sends a notification to the mobile station UE1 in all cells, in which the mobile station UE1 is suspected. Also the Mobile station UE2 is sent a notification. However, since the radio network controller RNC is known that the mobile station UE2 is in the cell Z, this is Alerts sent only in this cell Z.

The aforementioned notifications of radio network controller RNC contain advantageously an information, the reason for the notification, namely, Presence of multicast messages indicates. Especially can for alerts the existing RRC messages "Paging Type 1" and "Paging Type 2" used are already an information "Paging Cause", so the Reason for notification included. For the range of values this information "Paging Cause" can this example "No multicast message" added a value will.

The mobile station UE1, which in the RRC IDLE state MODE is, still has no signaling connection to the Radio network controller RNC constructed. Upon receiving the aforementioned notification builds the mobile station UE1 therefore first a signaling connection (RRC connection) to the radio network controller RNC on. The Mobile station UE2, which is located in the RRC state CELL_PCH, reactivates its signaling link by the radio network controller RNC by sending a confirmed RRC message that it is in the cell Z. The mobile stations UE1 and UE2 thus have a signaling connection constructed and are located in the RRC state CELL_FACH. You can therefore now signaling messages on a common transport channel 11 (eg, the FACH) and a general physical channel 10 (eg, the SCCPCH channel) received. As for the mobile station UE3 has been described, the signaling connection for receiving the resource allocation message "Multicast Channel Allocation Message "of the radio network controller RNC in two different ways be configured (case A or case B) (cf. above). The mobile stations UE1, UE2 and UE3 therefore are now in Multicast state 102 (see. Fig. 2).

If the signaling link for the transmission of the message "Multicast Channel Allocation Message" under Case A configured, sends the RRC layer of the radio network controller RNC now a signaling message to the RLC layer, which possibly adds control data and then on a general logical control channel 12 (Eg the SHCCH Channel) forwards it to the MAC layer. The MAC layer detects that the message on a general Control channel passes from the RLC layer to the MAC layer is and a common transport channel to the physical Layer PL is to be forwarded. Therefore, adds the MAC layer of a message control information TCTF added and includes this information about the value of "SHCCH". subsequently is the message via a common transport channel 11, as the FACH, forwarded to the physical layer PL, which they have a common physical Channel 10 (eg, the SCCPCH channel) to all mobile stations sends in the cell Z, which in the RRC state CELL_FACH or CELL_DCH are. In the present embodiment these are the mobile stations UE1-5. These mobile stations receive the message on the general physical Channel 10 and give them to their physical layers PL further that the message on the common transport channel 11 forwarded to the MAC layers. The MAC layers Refer to the field TCTF the MAC control information, that the message on the common logical SHCCH control channel is to be forwarded. The MAC layers then remove the MAC control information and forward the message through general logic SHCCH control channel to the RLC Schichen on. The RLC layers Remove now turn any existing control information and pass the message to the overlying them RRC layers on.

The resource allocation message includes the configuration the general transport channel 11 and the general physical Channel 10, which for the subsequent transmission the multicast messages to be used. also is an identifier for the multicast group A, as well as a Start and end time that indicates how long the resource the multicast group A should be assigned to contain. Alternatively, once one or more configurations the general transport channel 11 and the general physical channel 10 for transmitting multicast messages are to be used, to all mobile stations Sending the cell Z and the configuration identifiers be assigned to. For this case, the resource allocation message contains instead of the actual configuration only the respective identifier, so that the Mobile stations it to the desired configuration can close.

Since in this embodiment, the mobile stations UE1-5 are in the RRC state CELL_FACH, get this resource allocation message. However, since only the mobile stations UE1-3 the multicast group A include, discard the mobile stations UE 4 and UE5 resource allocation message, as they does not have the multicast address or the multicast identifier, is what in this message identifies will. The mobile stations UE1, UE2 and UE3 to recognize Hand of multicast identifier that multicast messages to be transferred to them.

If the signaling link for transmitting the resource allocation message configured according to Case B, sends the RRC layer of the radio network controller RNC is now a Signaling message to the RLC layer of the message possibly adds control data and then on the logical multicast control channel (MCCCH) 12 to the MAC layer forwards. The MAC layer detects that the Message on a logical multicast control channel of the RLC layer has come to the MAC layer and a common transport channel 11 to the physical layer PL to be forwarded. Therefore, the MAC layer adds the Send the control information TCTF which the value "MCCCH" is assigned, and the field MCID which the multicast group identifier contains, added (see. Fig. 4). Subsequently, the message is sent to the physical layer PL forwarded that this a general physical Channel 10 (eg, the SCCPCH channel) to all mobile stations sends in the cell Z, which in the RRC state CELL_FACH or CELL_DCH are (in this case the Mobile stations UE1-5). These receive the message on the general physical channel 10 and pass it along to the physical Layers PL further that the message on the common transport channel 11 forward it to the MAC layers. The MAC layers refer to the MAC control information the TCTF field, that the message on the particular logical Multicast Control Channel (MCCCH) are passed 12 should. From this, the MAC layers also recognize that a Another check array MCID follows. The MAC layer of a each mobile station then determines whether the respective mobile station identified by the identifier specified in the field MCID becomes. In this embodiment, this is for the Mobile stations UE1-3 the case. Remove Their MAC layers thus the control information and forward the message on MCCCH the channel to the overlying them RLC layers continue. The RLC layers remove their turn may existing control information and pass the message to the RRC layers on. The RRC layers must in this not check, whether the message for a multicast group has been sent, to which the respective mobile station belongs, as this already happened in the MAC layers is. As has already been mentioned, contains the resource assignment message the configuration of the general Transport channel 11 and the general physical channel 10, which used for transmission of the multicast message to be. In addition, an information about the time contain start and end times, which is indicated, how long the resource assigned to the multicast group A should be. Alternatively, in turn, may include one or more Configurations of the general transport channel 11 and the general physical channel 10, of the transmission Multicast messages are used to all mobile stations Sending the cell Z and the corresponding configurations Identifiers have been assigned. For this Case contains the resource allocation message instead of actual configuration, only the identifier for Selection of the respective configuration.

The mobile stations UE1, UE2 and UE3 now configure the common transport channel 11 and the general physical Channel 10, which for the transmission of multicast messages to be used in accordance with the resource allocation message Information contained.

The configuration of the BMC layer, the RLC layer, the MAC layer and the physical layer PL is illustrated in Fig. 3.

The BMC layer is already configured a multicast unit MCU is built within the BMC layer. This multicast unit is inventively all multicast messages receive the multicast group A and on the to the higher level connection V1 to the desired application pass the multicast group A. Furthermore, there is already a further connection V2 between the multicast unit MCU in the BMC layer and an RLC entity in RLCU the RLC layer. The RLC entity is a general logical channel 12 for transmitting general data, in UMTS designated CTCH ( "Common Traffic Channel"), with the MAC layer is connected. Within the MAC layer is that general logical channel 12 on the newly configured general Transport channel 11 for transmission of multicast messages to be used and in turn in the physical layer PL on the transmission of multicast messages provided general physical channel is imaged 10, ready.

To the one defined in the resource allocation message Start time catch the mobile stations UE1-3 to, on the general physical channel to receive data 10. To the same time captures the radio network controller RNC RNC to send the multicast messages. included this the transmitted multicast message packets an identifier the respective addressed multicast group, in the present Case of the multicast group A. The received multicast message packets be on the general transport channel 11 and the logical channel 12 to the corresponding RLC entity passed RLCU and from there via the connection V2 forwarded to the multicast unit MCU in the BMC layer. In the multicast unit MCU is the multicast message via the further connection to the corresponding application V1 forwarded.

In the signaling message is - as already mentioned is - a start and end time indicated that describe the length of time for the duration of the resources the general transport channel 11 and the general physical been channel 10 assigned to the multicast group A are. After that duration, ends the radio network controller RNC the transmission of multicast messages to this multicast group. The mobile stations UE1-3 build the common transport channel 11 and the general physical channel from 10th If the mobile stations, the Remove signaling connections, that is in the RRC state IDLE MODE or switch to the RRC state URA_PCH or CELL_PCH, they are situated according to the invention in the multicast state 101. If there are the signaling connection, Are they in the RRC state CELL_FACH or CELL_DCH, ie the corresponding mobile station is located by degradation the general transport channel 11 and the general physical Channel 10 according to the invention in the multicast state 102 (See. Fig. 2).