SE517498C2 - Connecting general packet radio service radio access network to universal mobile telecommunication system core network using temporary block flow and radio bearer - Google Patents

Abstract

At least one radio bearer is established, 801, at least one temporary block flow is established, 802, at least one radio bearer is associated with each of the temporary block flows, 803 and a reduced radio bearer identity is mapped to the real radio bearer identity. The reduced radio bearer identity is then included in the header of a radio link control/media access control header, 805 in order to inform the receiver of the radio bearer to which the data belongs. Independent claims are included for a computer readable medium with a program and for a radio communication system.

Description

20 25 30 35 517 498 2 data speeds up to 384 kbit / s, and potentially higher in high quality radio environments. In addition, GPRS allows your users to share the same radio interface resources and enables operators to charge customers for wireless services based on the amount of data transmitted instead of connection time.

The present invention is particularly applicable in the GSM / EDGE Radio Access Network (GERAN), wherein GPRS radio access networks are connected to Universal Mobile Telecommunications System (UMTS) core networks.

For GERAN release 5, the RAB (Radio Access Bearer) and RB (Radio Bearer) concepts from UMTS will be introduced.

Below are some key features of GPRS discussed in more detail.

GPRS radio interface, also called Um, is the logical link between the mobile station (MS) and the base station system (BSS). BSS may include a Base Station Controller (BSC) or a Radio Network Server (RNS) and a Base Transceiver Station (BTS).

RLC / MAC and the physical layers within the GPRS protocol stack, which are relevant to the invention, are described below.

RLC / MAC The radio link protocol, Radio Link Control (RLC), provides a radio solution-dependent reliable link. The access control function, Medium Access Control (MAC), controls access signaling (request and grant) procedures for the radio channel, and mapping of data frames from higher layers on the GSM physical channel (also referred to as GSM RF). The RLC / MAC layer is further described below.

Logical Link Control Layer (LLC), frames received from the Serving GPRS Support Nodes (SGSN), see Figure 2, in a downlink transmission and are divided into smaller RLC / MAC blocks, which are encoded into radio blocks on the physical stored.

Each radio block is transmitted in four consecutive bursts on a time slot (time slot TS). For example, if an MS is assigned time slot one to four, a radio block is transmitted in four bursts on time slot one, a second radio block is transmitted in four bursts on time slot two, etc. The transmission of packets to or from a certain MS is called a Temporary Block Flow (TBF). The equivalent of a call setup is an assignment of an uplink or downlink TBF for a packet transmission.

An MS can have a TBF in one direction or one in each direction. Each TBF is addressed by a Temporary Flow Identity (TF1) assigned by the network. When a TBF is assigned, the mobile is informed which time slot (s) it is to use and its TFI address.

A number of MSs can be allocated resources at the same time slot (s). The header of each downlink track block contains a TFI that shows which MS the radio block is addressed to.

The head of each downlink track block also contains a state link for the uplink, the Uplink State Flag (USF). The USF is used to notify the MSs who have uplink TBFs on that time slot, which of them is allowed to send an uplink radio block in the next group of four bursts.

Some of the different parts of the system are discussed further below.

TBF in (E) GPRS A Temporary Block Flow (TBF) is established when data is transmitted over the radio interface in (E) GPRS. Each T BF over the RLC / MAC layer is assigned a Temporary Flow Indentity (TF I) by the network. The mobile station shall assume that the TFI value is unique among simultaneous TBFs in the same direction (uplink or downlink) on all Packet Data Traffic Channels PDCH used for TBF.

The same TFI value can be used simultaneously for TBF on other PDCHs in the same direction or for TBF in the opposite direction. Up to 32 TBF can be established in each direction per PDCH.

An RLC / MAC block associated with a particular TBF should include a TF I.

TFI is used to uniquely identify the mobile station during packet transfer mode in an uplink or downlink RLC / MAC control message.

TBF in GERAN TF I in GERAN release 5 identifies a TBF for shared channels, and dedicated channels if MS has multiple fates on the same dedicated channel. TFI is a temporary identifier and can exist as long as there is data to be transmitted on the shared channel, or TFI can also be retained for a longer period of time. For dedicated channels, the data fate is identified by a TFI, which is permanent for at least as long as the dedicated channel is allocated, or the TBF may consist of a sequence and a set of time slots provided there is only one fate on the channel. TFI is assigned as for GERAN release 99.

The length of the TFI in GERAN release 99 is 5 bits.

Radio Access Bearer in UMTS A Radio Access Bearer (RAB) connection UMTS is realized through two subsequent segments, the Carrier Connection, between UMTS terrestrial radio access networks (UTRAN) and the core network, and Radio Bearerl (RB). _the connection, over the radio interface, referred to as Uu (iron-based with Um in GPRS).

RAB can be seen as the service provided by MS. RAB is defined by a set of Quality of Service (QoS) parameters such as range and it is set up for IPDP context activationf. Up to 256 RAB can be established per UE over Iu. of unequal error protection is required, each of these sub-feats is then realized over the radio as a radio bearer.

RB identified for UTRAN / GERAN The RB identifier (RB Id) identifies a radio bearer over the UU UU interface. An RB can carry signaling or use data and each RB maps to an RLC device. A total of 32 RB / MS is supported in the UTRAN via the radio interface. Since the same type of services are expected to be supported in GERAN as UTRAN, it is likely that GERAN will be able to support a maximum number of 32 radio carriers over the air.

Summary of the Invention The object of the present invention is to connect GPRS radio access networks to UMTS core networks to send data packets to and from a mobile station and achieve a system where the performance of the current GPRS system is improved. The object mentioned above is achieved by a method and a system according to the characterizing part of the independent claims.

Radio communication systems provided by the present invention include means for establishing at least one RB, means for establishing at least one TBF, and means for associating at least one RB to each OT BF, making it possible to connect GPRS radio access networks to UMTS core networks. to send data packets to and from a mobile station and achieve a system that improves the performance of the current GPRS system.

The method provided by the present invention comprises the steps of establishing at least one RB; establishing at least one TBF, and associating at least one RB to each of the at least one TBF, makes it possible to send data packets to and from a mobile station when GPRS radio access networks are connected to UMTS core networks.

An advantage of the present invention is that it makes it possible to reuse parts of UMTS for GPRS and thereby obtain coordination advantages to make the two systems more similar to each other.

Preferred embodiments are further defined in the dependent claims.

According to a second embodiment of the present invention, your RBs are associated with a TBF. A reduced RB identity is mapped to a true RB identity. The reduced RB identity is included in the header of an RLC / MAC packet to inform a recipient from which the RB data belongs.

An advantage of the second embodiment is that the signaling requirements are reduced and thereby the time delay.

Another advantage of the second embodiment is that the reduced RB identity saves space in the data packets.

Brief Description of the Drawings Figure 1 illustrates the basic configuration of a cellular mobile telecommunication system.

Figure 2 illustrates an example of a communication system in which the present invention can be implemented.

Figure 3 is a diagram showing the protocols affected by the radio interface according to a first embodiment of the present invention.

Figure 4 is a diagram showing the protocols affected by the radio interface according to a second embodiment of the present invention.

Figure 5 is a diagram showing the protocols affected by the radio interface according to a second embodiment of the present invention.

Figure 6 shows an uplink RLC / MAC data block header for MCS-1-4.

Figure 7 shows a downlink RLC data block header for MCS-1, MCS-2, MCS-3 and MCS-4.

Figure 8 shows a fate diagram of the method in accordance with the present invention.

Figure 9 shows a radio communication system in accordance with the present invention.

Detailed Description of Preferred Embodiments Figure 2 illustrates an example of communication system 2 in which the present invention may be implemented. In particular, the system 2 shown in Figure 2 is adapted to the GSM specifications and supports GPRS and Enhanced GPRS (EGPRS) (eg GERAN) technology. The mobile telecommunication system 2 includes a circuit-switched network 4, a packet-switched network 6, and a radio network 8 which is shared by the circuit-switched and packet-switched networks 4 and 6. In general, the circuit-switched network 4 is primarily used for voice applications, while the packet-switched network 4 connected network 6 primarily used for data applications. In accordance with the third generation mobile telecommunication standard, the circuit-switched network 4 can also support data communication, and the packet-switched network 6 can also support voice communication.

The circuit-switched network 4 includes a number of mobile services switching center / visitor location registers (MSC / VLRs) 12. For the sake of simplicity, only one MSC / VLR 12 is shown. Each MSC / VLR 12 handles a special 10 15 20 25 30 517 498 7 geographical area and is used to control communications in the managed area and to route communications to other MSC / VLRs 12. The VLR portion of the MSC / VLR 12 stores subscriber information related to mobile stations 10 currently located in that area. processed by MSC / VLR. The circuit-switched network 4 further includes at least one gateway mobile services switching center (GMSC) 14 which connects the circuit-switched network 4 to external networks, such as a public switched telephone network (PSTN) 16.

The packet-switched network 6 includes a number of Serving GPRS Support Nodes (SGSN) 18, which are used to route and control packet data communication, and a backbone IP network 20. A gateway GPRS support node (GGSN) 22 connects the packet-switched network 6 with an external IP. network 24 or other external data networks.

The radio network 8 includes a plurality of cells, each cell in the mobile communication system 2 being managed by a base station 26 which communicates with mobile stations 10 in the cell via a radio interface 28. The radio network 8 comprises a number of base stations 26 and a base station controller (BSC) 27, alternatively referred to as a Radio Network Controller (RN C) or Radio Network Server (RN S), which controls the said base stations 26. For circuit-switched communications, signals are routed from the MSC / VLR 12 to the base station controller 27 via an interface 34, to the base station 26. for the cell where the target mobile station 10 is currently located, and over the radio interface 28 to the mobile station 10. For packet data transmissions, on the other hand, signals are routed from SGSN 18 to base station controller 27 via an interface 25 to the base station 26 for the cell where the target mobile station 10 currently available, and over the radio interface 28 to the mobile station 10.

Each mobile station 10 is associated with a home location register (CPR) 30. CPR 30 stores subscriber data for the mobile station '10 used in connection with circuit-switched communications and can be accessed by MSC / VLR 12 to retrieve subscriber data related to circuit-switched services. Each mobile station 10 is also associated with a GPRS register 32. The GPRS register 32 stores subscriber data for the mobile station 10 used in connection with packet-switched communications and can be accessed through SGSN 18 for retrieval. subscriber data relating to packet-switched services.

Mapping an RB on a TBF According to a first embodiment of the present invention, an RB is mapped on a TBF.

In a first scenario, a mobile station (MS) has 2 RBs set up: RB1 and RB2. Figure 3 shows the protocols affected by the radio interface according to this first embodiment of the present invention. PHY stands for Physical Layer.

The following happens on the uplink: a) MS needs to send data for a first RB, ie. RB1.

A TBF, i.e. TBF1, set up for RB1: No data needs to be sent for RB2 at first.

Here MS sends TBF1 which is associated with RBI. b) MS then needs to send data for the second RB, ie. RB2. According to the first embodiment, a new TBF needs to be set up for RB2. To do so, the MS must wait for the network to poll, so it must send a "Packet Resource Request" message and receive a response from the network. The answer is a "Packet Uplink Assignment" that assigns a new TBF, ie. TBF2 associated with RB2.

Then, when the network polls the MS again, the MS can start sending data for the RB2.

This embodiment is a solution for reusing parts of UMTS for GPRS and thereby obtaining coordination benefits by making the two systems more similar to each other. Although this means a delay (see below) before data can be transmitted for RB2. The solution for mapping RB on TBF according to the second embodiment (see later under "Mapping fl your RB on a TBF") has no delay.

The delay before data can be sent for RB2 is 40 ms (20 ms for "Packet Resource Request" + 20 ms for "Packet Uplink Assignment") + the time MS needs to wait before it is polled. In addition, two signaling messages need to be sent.

The following happens on the downlink: a) If a TBF is needed, TBF1 is associated with RB1. b) If a second TBF is needed, the network must send a "Packet Downlink Assignment" to set up a new TBF for the second RB, before data can be transmitted for this RB, ie. TBF2 is associated with RB2.

Mapping of your RBs on a TBF There is a desire to save TBFs by using more than one RB per TBF at the same time. When examining the different layers, an RB is the one that comes on top of the Packet Data Convergence Protocol (PDCP), while a TBF is what the MAC offers the physical layer. At each layer, multiplexing can occur so that fl your entities can be mapped to an entity for the underlying layer. In a second embodiment of the present invention, multiplexing occurs at the PDCP and MAC layers.

The second embodiment describes a solution for multiplexing PDCP entities on TBF, which cover multiplexing at MAC levels. Multiple RBs are mapped on a TBF, and a reduced RB identity (reduced RB Id) is included in the RLC / MAC header to differentiate between different fl fates coming from different RBs. The real RB identifier is reduced to be more space-saving. An RB Id is proposed to be 5 bits in UMTS and a reduced RB Id according to the present invention can be as short as 2 bits. The space in the head is limited and it is assumed here that the reduced RB Id is 2 bits long but can of course be longer. The names of the fields introduced in the MAC header ("Reduced RB Id") and of what must be mapped to it ("RB Id") are used in accordance with this assumption.

Two scenarios of the second embodiment will be described. Both are based on the assumption that the reduced RB Id is 2 bits (x = 2), which means that the number of different reduced RB Id (n) is limited to four (OO, 01, 10, 11). Therefore, the method according to the second embodiment differs in the case where a number of reduced RB Id (n) is needed and is less than or equal to four and in cases where the required number of reduced RB Id (n) exceeds four. An MS intends to set up a number of RBs: RB 1, ..., RBn. Figure 4 shows the protocols affected by the radio interface according to the first scenario when n = <4 and where the mapping of the reduced RB Id is implicit.

Figure 5 shows the protocols affected by the radio interface according to the second scenario when n> 4 and where mapping of the reduced RB Id is explicit. 10 15 20 25 30 35 517 498 10 On the uplink the following happens: MS needs to send data for RB1 and a TBF ie. TBF1 is established for RB1, but it is advantageous to assign additional RB for TBF1 when TBF1 is established, even though MS currently only needs to send data for a small number of RBs. There is then no need for any reconstitution of TBF if it is necessary to send additional data for the other assigned RBs later. MS only needs to activate these RBs. To distinguish between different RBs, a reduced RB identity (reduced RB Id) is included in the RLC / MAC header. As mentioned before, it is assumed here that the space inside the head for the reduced RB Id is 2 bits long.

This means that if n = <4, the mapping between the 2-bit reduced RB Id to the actual RB Id can be implicit, ie. for 2 bits there are only four reduced RB Id namely 00, Ol, 10 and ll. According to the example of the first scenario shown in Figure 4, MS needs to send data for RB1 but has established TBF1, which is assigned for four RBs, ie. RB1, RB2, RB3 and RB4. The lowest real RB Id is e.g. mapped to the lowest reduced RB Id, for example for RB1 a reduced RB Id can be OO, for RB2 e.g. Ol, for RB3 e.g. 10 and for RB4 e.g. l 1. If MS later wants to send data for RB2, the transmission of data can start directly by using TBF1 and RB2 which have the reduced RB Id Ol.

If n> 4, i.e. MS needs to send data for RB1 but has established a TBF1 assigned e.g. for RB1, RB2, RB3, RB4 and RB5 shown in Figure 5, mapping between 2-bit reduced RB Id and the actual RB Id must be done explicitly. The reduced RB Id is used to distinguish between different flows coming from different RBs, but the actual RB Id must be included in the information section to inform the receiver from which the RB data belongs. If n> 4, at least 2 TBFs need to be set up if we still assume that the length of the reduced RB Id is two bits, since then it is only possible to distinguish between a maximum of four data fl feats on each TBF. In the example of the second scenario shown in Figure 5, TBF1 is established which is assigned to RBI, RB2, RB3 and RB4. For RB1 a reduced RB Id can be OO, for RB2 Ol, for RB3 10 and for RB4 11. Furthermore, TBF2 is established and assigned for RB5 and the reduced Id mapped on RB5 can e.g. be OO. The distribution of RB to TBF can be done in many ways, e.g. two RBs for TBF1 and three RBs for TBF2 etc. The limit is the one up to a maximum of four (2x) RBs that can be assigned to a TBF if the space inside the head for the reduced RB Id is 2 bits long (x = 2). If the space within the header of the reduced RB Id is 3 bits long (x = 3), a maximum of eight RBs can be assigned to a TBF. It should be noted that a bit in the information part can be used to indicate whether the actual RB Id is included in the information part or not, preferably the first bit.

If the RB uses an "acknowledged" RLC entity and n> 4, the actual RB Id for RB2 only needs to be included in the information portion of the first data block, because if the network does not receive it, the MS will retransmit it anyway.

If the RB uses an "unacknowledged" RLC entity and n> 4, the real RB2 must be included in the header of all data blocks transmitted with the new reduced RB Id (or perhaps until the first acknowledge / non-acknowledge (ack / nack) report is received by the network if MS polls for ack / nack).

On the downlink a) A TBF, TBF1, is set up between the network and the MS and the reduced RB Id OO is used for RBI. b) The data transmission for RB2 can start immediately provided that RB2 is associated with TBF1 in the allocation of TBF1, and that it uses another reduced RB Id.

The coupling between the actual RB Id and the reduced one can be implicitly or explicitly transmitted depending on the number of established RBs and allocated bits for the reduced RB Id.

Mapping of reduced RB Id to RB for n = <4 and n> 4 are provided in the same way for the above case for uplink.

Compared to the solution for mapping an RB to a TBF, this solution does not provide any delay before data can be sent on an additional RB, as no new TBFs need to be set up.

Include reduced RB Id in RLC / MAC data block header.

The number of spare bits in the current EGPRS RLC / MAC data headers is very limited. Therefore, some fields must be renamed to include a reduced RB Id in the header: For the uplink .. *. '1. An RLC / MAC data block is encoded with one of the available channel coding schemes MCS-1, MCS-2, MCS-3, MCS-4, MCS-S, MCS-6, MCS-7, MCS-8 or MCS-9.

Figure 6 shows an uplink RLC / MAC data block header for MCS-1-4. For MCS-1-4, it is suggested to use the Spare and PI fields for a reduced RB Id of two bits in length. It may also be possible to use the RSB and R-bits if the number of bits on the reduced RB Id must be increased in the future. Currently, RLC / MAC data headers for MCS 5-9 are uplinked, there are enough spare bits that can be used for the reduced RB Id.

For the downlink Since the downlink RLC data headers do not contain any spare bits at all, we suggest using the RRBP (Relative Reserved BLock Period) field for a 2-bit RB Id.

Figure 7 shows the downlink RLC data block header for MCS-1, MCS-2, MCS-S and MCS-4.

The RRBP value can be signaled when the TBF is set up and is fixed during the TBF.

Different lengths can be used for reduced RB lol fields on the uplink and downlink, and some other fields can be reused instead or in addition to those mentioned.

Mapping between the reduced RB Id and the actual RB Id when TBF is set “PP When a transmitter, whether it is the network or the mobile, has data to send for a particular RB, it first needs to establish a TBF to send data.

On the downlink On the downlink a "Packet Downlink Assignment" message is sent from GERAN to MS: In this message the identity of the RB (s) for which this TBF has been established must be indicated, as well as the reduced RB Id (s). ) to which it is mapped.

On the uplink On the uplink, a TBF can be established in two ways: l) In the two-phase access case, the MS sends a "Packet Channel Request" message to the network on the Random Access Channel (RACl-I) or 10 15 20 25 30 35 517 498 13 Packet Random Access Channel (PRACH). In this message, the MS indicates that it wants to allocate an uplink block. The network then responds with a "Packet Uplink Assignment" and allocates an uplink block to the MS, in which block the MS sends a "Packet Resource Request" requesting that an uplink TBF be established. the reduced RB Id (s) for which it / they are mapped can be indicated in the last message.The network responds with another "Packet uplink Assignment" where the mapping between the actual RB Id and the reduced RB Id can also be sent. 2) An ARI based access can also be performed: in that case MS has previously been allocated an "ARI" (Access Request Identities), in which case MS ARI includes in "Packet Channel Request" which it sends on PRACH or RACI-I A "Packet Uplink Assignment" that allocates TFI is then sent directly to the MS, as the MS has been identified by the ARI. Although your ARIs can be allocated to the same user, there is a case where an ARI does not identify the RB for which access is performed. When the data transmission begins, a mechanism must be introduced in the network to understand which RB the data is intended for. To give the connection between the reduced RB Id used and the real identity of the RB for which the data is intended, two methods are proposed: I. If ARI can be used for n <= 4 RB, mapping can be done implicitly: if MS e.g. . using reduced RB Id OO means that data is intended for RB with the lowest identity and so on II. Another method that can be used more generally consists of introducing the real RB Id in the information part of the blocks: a first bit of the information part, called the Identity Indicator (II) bit, should indicate whether the real RB Id has been included in the rest of the information part or not. N is data transmission begins after an ARI-based access, MS selects a reduced RB Id to send data for the RB that has data to send. The actual RB Id is included in the information part of the first blocks, and is indicated by the II bit. If the RLC mode of RB is "acknowledged", the real RB Id can only be included in the information part of the first block, as this block will be returned until the network has managed to receive it. If the RLC mode of RB is unacknowledged, RB Id should be included in the information section until an Ack / Nack report is received by the MS indicating that at least one block has been correctly received.

It should be noted that the two methods are not exclusive and can be used complementary.

The following applies to both uplink and downlink: A timer can be used when a reduced RB Id is to be taken down, it can be the same for all RBs or RB dependencies (in which case it can be sent during RB setup). A control message can also be used for reduced RB Id reallocation, ie. the mapping between the reduced RB Idzn and the actual RB Idzn is changed to avoid sending Packet uplink (or downlink) assignments which are very large messages. The mapping between the reduced and actual RB Idzars is performed as described above.

Figure 8 shows a fate diagram of a method in a packet-switched radio communication system for transmitting packets over a radio interface to or from a mobile station (MS), wherein the system uses Temporary Block Flow (TBF) and Radio Bearer (RB) concepts according to the invention. in a general mod.

The method comprises the following steps: 801. At least one RB is established. 802. At least one TBF is established. 803. At least one RB is associated with each of the at least one TBF. 804. A reduced RB Id is mapped to a real RB Id. 805. The reduced RB Id is included in a header of an RLC / MAC packet, to inform the receiver from which the RB data belongs.

The method has been implemented using a computer software product that includes software code components to perform the method steps. The computer program product is run on a computer stored in a base station system and in the mobile station, within the packet-switched radio communication system. The computer program is loaded directly or from a computer usable medium, such as an optical disk, a CD, the Internet, etc. Figure 9 shows a packet-switched radio communication system according to the present invention, in which data packets can be sent over a radio interface 901 between a mobile station 900 and a base station system 903. The mobile station 900 and the base station system 903 are included in a radio access network such as e.g. Enhanced GPRS (EGPRS). The base station system 903 is connected to the UMTS core network 905.

The system uses Temporary Block Flow (TBF) and Radio Bearer (RB) concepts.

The system includes means 902 for establishing at least one RB; means 904 for establishing at least one TBF and means 906 for associating at least one RB to each of the at least one TBF. A true RB Identifier (RB Id) identifies an RB across the radio interface to differentiate between different fates coming from different RBs. The system includes means 908 for mapping a reduced RB Id to an actual RB Id to become more space saving and to handle a number of RBs associated with a TBF. An RB Id is proposed to be 5 bits long as in UMTS and a reduced RB Id according to the present invention can be as short as 2 bits.

The system includes means 910 for including the reduced RB Id in a header of a Radio Link Control / Medium Access Control (RLC / MAC) packet, for informing a receiver from which RB data belongs.

The system further includes means for implicitly mapping reduced RB Id to actual RB Id, to handle the case where the number of established RBs is less than or equal to ZX and the reduced RB Id is x bits long. This means that, where the number of established RBs is less than or equal to 4, and the reduced RB Id is 2 bits long, the mapping may be implicit.

The system further comprises means for mapping reduced RB Id to actual RB Id on the uplink to handle the case where the communication system comprises a GSM / EDGE Radio Access network (GERAN) and in which an Access Request Identifier (ARI) based access is performed.

This means that for mapping the reduced RB Id to the actual RB Id can be performed explicitly if the number of established RBs exceeds 2X, and the reduced RB Id is x bits long. Which means that if the number of established RBs exceeds 4, in the case where the reduced RB Id is 2 bits long. Explicit mapping can also be performed when the number of established RBs is less than or equal to 2X.

Explicit mapping is possible in a system that includes means for including the actual RB Id in the information portion of said RLC / MAC packet. The system further comprises means for using a bit in the information part to indicate whether the actual RB Id is included in the information part or not.

To handle cases where an acknowledged RLC entity is used by an established RB and the number of established RBs exceeds QX, e.g. four, the system further comprises means for including the full RB Id, only in a first data block of all data blocks transmitted with the mapped reduced RB Id.

To handle cases where an unacknowledged RLC entity is used by an established RB and the number of established RBs exceeds 2X, e.g. four, the system further includes means for including the full RB Id in all data blocks transmitted with the mapped reduced RB Id, until a first acknowledge or non-acknowledge report is received.

In one embodiment, the system comprises a GSM / EDGE Radio Access network (GERAN). In that case, the system may include means for indicating in a control message, such as a "Packet Downlink Assignment" message sent from GERAN to MS, the actual RB Id (s) for which a TBF has been established and the respective reduced RB Id to which the actual RB Id (s) are mapped. The system may further comprise means for indicating in a control message, such as "Packet Resource Request" message, sent from MS to GERAN, the actual RB Id (s) for which a TBF has been established and the respective reduced RB Id to which it / the actual RB Id are mapped.

The system may further comprise means for taking down a reduced RB Id by means of an indication from a timer and / or means for reallocating a reduced RB Id by sending a control message.

The present invention is not limited to the preferred embodiments described above. Various alternatives, modifications and equivalents can be used. Therefore, the embodiments described above should not be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims (36)

10 15 20 25 30 517 498 17 PATENT REQUIREMENTS Method in a packet-switched radio communication system for transmitting packets over a radio interface to or from a Mobile Station (MS), the system uses Temporary Block Flow TBF and Radio Bearer RB concepts, characterized in that the method comprises the steps of: at least one RB is established (80l); at least one TBF is established (802); at least one RB is associated (803) with each of the at least one TBF. A method according to the preceding claim, wherein a number of RBs are associated with each of the at least one TBF. A method according to the preceding claim, wherein a real RB identifier (RB Id) identifies an RB, the method comprising the further step: a reduced RB Id is mapped to a real RB Id. The method of claim 3, comprising the further step: said reduced RB Id is included in a header of a Radio Link Control / Medium Access Control (RLC / MAC) packet to inform a receiver from which the RB data belongs. A method according to any one of the preceding claims 3-4, wherein the number of established RBs is less than or equal to QX, and the reduced RB Id is x bits long, said mapping of the reduced RB Id to the actual RB Id is performed implicitly. The method of claim 5, wherein x is equal to two. .__,. A method according to any one of claims 3-6, the van / id communication system comprises a GSM / EDGE RAdio Access network (GERAN) and wherein an Access Request Identifier (ARI) based access is performed and wherein said mapping of the reduced RB Id to the actual RB Id is performed on the uplink. 10 15 20 25 30 517 498 18 The method of claim 3, wherein the number of established RBs exceeds QX, and the reduced RB Id is x bits long, said mapping of the reduced RB Id to actual RB Id is performed explicitly. A method according to the preceding claim, wherein x is equal to 2. The method of the preceding claim, wherein said explicit mapping is performed by: actual RB Id is included in the information portion of said RLC / MAC packet. A method according to the preceding claim, comprising the further step of using a bit in the information part to indicate whether the actual RB Id is included in the information part or not. A method according to any one of the preceding claims 8-11, wherein an established RB uses an acknowledged RLC entity and the number of established RBs exceeds 2X, the method comprising the further step of: the full RB Id being included only in a first data block of all data blocks which sent with the mapped reduced RB Id. A method according to any one of the preceding claims 8-1 1, wherein an established RB uses an unacknowledged RLC entity and the number of established RBs exceeds 2x, the method further comprising the step of: the full RB Id being included in all data blocks transmitted with the mapped reduced RB Id, until a first acknowledge or non-acknowledge report is received. A method according to any one of claims 3 to 13, wherein the communication system comprises a GSM / EDGE Radio Access network (GERAN), the method comprising the additional step to be taken in TBF setup on the downlink: a control message, sent from GERAN to MS, the / the actual RB Id is indicated for which a TBF has been established and the respective reduced RB Id to which the actual RB Id (s) are mapped. 10 15 20 25 30 517 498 19 A method according to any one of claims 3-14, wherein the communication system comprises a GSM / EDGE Radio Access network (GERAN), the method comprises the further step to be taken in the TBF setup on the uplink: a control message, sent from MS to GERAN, the / the actual RB Id for which a TBF has been established and the respective reduced RB ld to which the actual RB Id (s) are mapped. A method according to any one of claims 3 to 15, comprising the further step: removing a reduced RB Id by means of an indication from a timer. A method according to any one of claims 3 to 16, comprising the further step of: reallocating a reduced RB Id by sending a control message. A computer program product directly downloadable in the internal memory of a computer within a mobile station or base station system of a packet-switched radio communication system, comprising software code portions for performing the steps of any of claims 1-17. A computer program product stored on a computer usable medium, comprising a readable program for causing a computer, within a mobile station or a base station system in a packet-switched radio communication system, to control an execution for the steps of any of claims 1-17. Radio communication system for transmitting packets over a radio interface (901) to or from a Mobile Station (900), the system is packet-switched and uses the Temporary Block Flow (TBF) concept and the Radio Bearer RB concept, characterized in that the system comprises : means (902) for establishing at least one RB; means (904) for establishing at least one TBF; and means (906) for associating at least one RB to each TBF. The radio communication system of the preceding claim, wherein a plurality of RBs are associated with each of the at least one TBF. 10 15 20 25 30 517 498 20 A radio communication system according to the preceding claim, wherein a real RB identifier (RB Id) identifies an RB, the system comprising means (908) for mapping a reduced RB Id to a real RB Id. The radio communication system of claim 22, wherein the system further comprises means (910) for including said reduced RB Id in a header of a Radio Link Control / Medium Access Control (RLC / MAC) packet to inform a receiver from which RB data belongs . A radio communication system according to any one of the preceding claims 22-23, wherein the number of established RBs is less than or equal to QX, and the reduced RB Id is x bits long, the system further comprising means for mapping the reduced RB Id to the actual RB Id implicit. The radio communication system of claim 24, wherein x is equal to two. A radio communication system according to any one of claims 22-25, wherein the communication system comprises a GSM / EDGE Radio Access network (GERAN) and wherein an Access Request Identifier (ARI) based access is performed, the system further comprises means for mapping the reduced RB Id to the actual RB Id on the uplink. The radio communication system according to claim 22, wherein the number of established RB exceeds 2x, and the reduced RB Id is x bits long, said means for mapping the reduced RB Id to the actual RB Id being performed explicitly. The radio communication system of claim 27, wherein x is equal to 2. The radio communication system of claim 28, wherein said explicit mapping is possible by including the actual RB Id in the information portion of said RLC / MAC packet. 10 15 20 25 30 517 498 21 The radio communication system of claim 29, further comprising means for using a bit in the information portion to indicate whether the actual Rb Id is included in the information portion or not. A radio communication system according to any one of the preceding claims 27-30, wherein an acknowledged RLC unit is used by an established RB and the number of established RBs exceeds 2X, the system further comprising means for including the full RB Id, only in the first data block of all data blocks sent with the mapped reduced RB Id. A radio communication system according to any one of the preceding claims 27-30, wherein an unacknowledged RLC entity is used by an established RB and the number of established RBs exceeds 2X, the system further comprising means for including the full RB Id in all data blocks transmitted with the mapped reduced RB Id, until a first acknowledge or non-acknowledge report is received. A radio communication system according to any one of claims 20-32, wherein the communication system comprises a GSM / EDGE Radio Access network (GERAN), the system further comprising means for indicating in a control message, sent from GERAN to MS, the actual RB Id (s) for which a TBF has been established and the respective reduced RB Id to which the actual RB Id (s) is mapped. A radio communication system according to any one of claims 20-33, wherein the communication system comprises a GSM / EDGE Radio Access network (GERAN), the system further comprising means for indicating in a control message, sent from MS to GERAN, the actual RB Id (s) for which a TBF has been established and the respective reduced RB Id to which the actual RB Id (s) is mapped. A radio communication system according to any one of claims 22-34, further comprising means for taking down a reduced RB Id by means of an indication from a timer. 517 498 22 The radio communication system of any of claims 22-35, further comprising means for reallocating a reduced RB Id by sending a control message.