FIELD OF THE INVENTION

This invention relates to a mechanism to support Internet Protocol data flows within a wireless communication system. The invention is applicable to, but not limited to, gateway queuing algorithms in packet data transmissions, for example, for use in the universal mobile telecommunication standard.

BACKGROUND OF THE INVENTION

In a cellular communication system, a geographical region is divided into a number of cells, each of which is served by base stations, sometimes referred to as Node-Bs. The base stations are interconnected by a fixed network which can communicate data between the base stations. A mobile station, sometimes referred to as user equipment (UE) is served via a radio communication link from the base station of the cell within which the mobile station is situated.

A typical cellular communication system extends coverage over an entire country and comprises hundreds or even thousands of cells supporting thousands or even millions of mobile stations. Communication from a mobile station to a base station is known as the uplink, and communication from a base station to a mobile station is known as the downlink.

The fixed network interconnecting the base stations is operable to route data between any two base stations, thereby enabling a mobile station in a cell to communicate with a mobile station in any other cell. In addition, the fixed network comprises gateway functions for interconnecting to external networks such as the Internet or the Public Switched Telephone Network (PSTN), thereby allowing mobile stations to communicate with landline telephones and other communication terminals connected by a landline. Furthermore, the fixed network comprises much of the functionality required for managing a conventional cellular communication network including functionality for routing data, admission control, resource allocation, subscriber billing, mobile station authentication etc.

Currently, the most ubiquitous cellular communication system is the 2nd generation communication system known as the Global System for Mobile communication (GSM). GSM uses a technology known as Time Division Multiple Access (TDMA) wherein user separation is achieved by dividing frequency carriers into 8 discrete time slots, which individually can be allocated to a user. Further description of the GSM TDMA communication system can be found in The GSM System for Mobile Communications' by Michel Mouly and Marie Bernadette Pautet, Bay Foreign Language Books, 1992, ISBN 2950719007.

Currently, 3rd generation systems are being rolled out to further enhance the communication services provided to mobile users. The most widely adopted 3rd generation communication systems are based on Code Division Multiple Access (CDMA) technology. Both Frequency Division Duplex (FDD) and Time Division Duplex (TDD) techniques employ this CDMA technology. In CDMA systems, user separation is obtained by allocating different spreading and scrambling codes to different users on the same carrier frequency and in the same time intervals. In TDD, additional user separation is achieved by assigning different time slots to different users similarly to TDMA. However, in contrast to TDMA, TDD provides for the same carrier frequency to be used for both uplink and downlink transmissions. An example of a communication system using this principle is the Universal Mobile Telecommunication System (UMTS). Further description of CDMA and specifically of the Wideband CDMA (WCDMA) mode of UMTS can be found in ‘WCDMA for UMTS’, Harri Holma (editor), Antti Toskala (Editor), Wiley & Sons, 2001, ISBN 0471486876.

In a 3rd generation cellular communication system, the communication network comprises a core network and a Radio Access Network (RAN). The core network is operable to route data from one part of the RAN to another, as well as interfacing with other communication systems. In addition, it performs many of the operation and management functions of a cellular communication system, such as billing. The RAN is operable to support wireless user equipment over a radio link of the air interface. The RAN comprises the base stations, which in UMTS are known as Node Bs, as well as Radio Network Controllers (RNCs) which control the base stations and the communication over the air interface.

The RNC performs many of the control functions related to the air interface including radio resource management and routing of data to and from appropriate base stations. It further provides the interface between the RAN and the core network. An RNC and associated base stations are known as a Radio Network Subsystem (RNS).

3rd generation cellular communication systems have been specified to provide a large number of different services including efficient packet data services. For example, downlink packet data services are supported within the 3GPP release 5 specifications in the form of the High Speed Downlink Packet Access (HSDPA) service. A High Speed Uplink Packet Access (HSUPA) feature is also in the process of being standardised. This uplink packet access feature will adopt many of the features of HSDPA.

In accordance with the 3GPP specifications, the HSDPA service may be used in both Frequency Division Duplex (FDD) mode and Time Division Duplex (TDD) mode.

In HSDPA, transmission code resources are shared amongst users according to their traffic needs. The base station or “Node-B” is responsible for allocating and distributing the resources to the users, within a so-called scheduling task. Hence, for HSDPA, some scheduling is performed by the RNC whereas other scheduling is performed by the base station. Specifically, the RNC allocates a set of resources to each base station, which the base station can use exclusively for high speed packet services. The RNC furthermore controls the flow of data to and from the base stations.

Therefore, most packet based systems contain schedulers that control when the individual data packets are transmitted, in order to share the available resource, whether time-slots in a time division multiple access (TDMA) communication system or power and codes in a code division multiple access (CDMA) communication system. An introduction to schedulers can be found in ‘Service discipline for guaranteed performance service in packet-switching networks’, authored by Hui Zhang, and published in the Proceedings of the IEEE, volume 83, no. 10, October 1995.

U.S. Pat. No. 6,845,100 describes use of two separate schedulers; a packet scheduler and a QOS scheduler. The packet scheduler allocates resources to users and then within this user's allocation the QoS scheduler prioritizes some packets over other depending upon the radio bearer they are assigned to.

Thus, there exists a need to provide an improved mechanism to differentiate between IP data flows.

SUMMARY OF THE INVENTION

In accordance with aspects of the present invention, there is provided a wireless communication system, an apparatus, and a method of operation therefor, as defined in the claims.

Accordingly, in one embodiment of the present invention there is provided an apparatus for use in allocating resource in a wireless communication system, the apparatus comprising mapping logic arranged to map one or more services to individual radio bearers of a plurality of radio bearers; reporting logic arranged to indicate buffer occupancy for the plurality of radio bearers; and prioritization logic arranged to prioritize the allocated resource across multiple wireless communication units on a radio bearer basis.

The provision of prioritization logic arranged to prioritize allocated resource across multiple wireless communication units enables prioritization of a particular service across users, so that for instance hyper text transport protocol (HTTP) traffic can be prioritized over file transfer protocol (FTP) traffic, whether the FTP traffic was associated with one user or a number of other users.

In one embodiment of the present invention, the apparatus comprises a database storing a plurality of service specifications, one per wireless communication unit, that define the mapping between data flow and respective radio bearers.

The provision of a database storing a plurality of service specifications provides a very wide range of mapping characteristics can be configured. Furthermore, different mappings can be achieved on a per tier or even per user basis.

In one embodiment of the present invention, the apparatus further comprises signal dividing logic operably coupled to mapping logic and arranged to split services into individual radio bearers from a single (PDP) context.

The provision of the signal dividing logic provides user equipment with the ability to no longer need to send a secondary packet data protocol (PDP) context request to begin a new service, thereby avoiding significant latency.

In one embodiment of the present invention, the wireless communication unit is user equipment arranged to allocate resource in an uplink communication path.

In one embodiment of the present invention, the apparatus is located in a radio access network (RAN) that comprises prioritization logic arranged to allocate resource to a plurality of wireless communication units in a downlink communication path on a radio bearer basis.

In one embodiment of the present invention, a wireless communication unit of the plurality of wireless communication units comprises a signal processor arranged to identify buffer occupancy for individual radio bearers and a transmitter operably coupled to the signal processor and arranged to transmit a message to the radio access network.

The provision of a signal processor arranged to identify buffer occupancy for individual radio bearers (or services) advantageously enables any system to provide prioritization, whether within a users allocation or across users. In one embodiment of the present invention the message indicates separate buffer occupancy for each of the radio bearers.

The provision of a message that indicates separate buffer occupancy for each of the individual radio bearers provides effective prioritization, in that the allocator knows the buffer occupancy for each radio bearer (RB), in the UL direction. This supports signalling to enable the UE to report this volume.

In one embodiment of the present invention, the apparatus further comprises weighting logic operably coupled to the signal processor and the prioritization logic and arranged to provide a set of weight values for each service across a plurality of users such that the prioritization logic allocates bandwidth resource to individual radio bearers according to a set of weight values.

The provision of weighting logic operably coupled to the signal processor and the prioritization logic allows a proportion of the resource to be allocated to particular radio bearers (e.g. services). This is in contrast to the conventional prioritization scheme provided by 3GPP, which uses a simple absolute priority scheme.

In one embodiment of the present invention, the apparatus further comprises a transmitter transmitting the set of weight values to the wireless communication unit. This feature provides the advantage that the UE can then properly prioritize traffic whilst receiving a single physical allocation from the network and not have to use the simple absolute priority system defined in 3GPP.

In one embodiment of the present invention, the radio access network comprises a scheduler arranged to schedule prioritized allocated resource across multiple wireless communication units in response to the message.

In one embodiment of the present invention, the radio access network comprises a plurality of classifiers associated with the one or more services operably coupled to the mapping logic such that the mapping logic maps data packets onto respective radio bearers.

The provision of classifiers associated with the one or more services advantageously supports the filtering of services onto radio bearers.

In one embodiment of the present invention, there is provided an apparatus comprising a memory and a processor operably coupled to the memory. Program code is executable on the processor, where the program code is operable for mapping one or more services to individual radio bearers of a plurality of radio bearers; reporting buffer occupancy for the plurality of radio bearers; and prioritizing the allocated resource across multiple wireless communication units on a radio bearer basis.

In one embodiment of the present invention, a wireless communication system comprises a radio access network facilitating communication to a plurality of wireless communication units. The wireless communication system comprises mapping logic arranged to map one or more services to individual radio bearers of a plurality of radio bearers; reporting logic arranged to indicate buffer occupancy for the plurality of radio bearers; and prioritization logic arranged to prioritize the allocated resource across multiple wireless communication units on a radio bearer basis.

In one embodiment of the present invention, a method for limiting a number of services supported at an instant of time in a wireless communication system is described. The method comprises determining a normalised service weighting parameter of allocated resources; determining a number of resource allocation units allocated to each service; and determining whether the number of services that have resources allocated is greater than a threshold. The method further comprises limiting a number of resource allocation units allocated in response to the number of services that have resources allocated is greater than a threshold; re-calculating a number of resource allocation units allocated to each service; and ordering services in an order of resource allocation units allocated to each service, and select a number from the ordered services. The method further comprises setting all services not selected to zero; determining whether the number of services that have resources allocated is greater than a threshold; and when said number of services that have resources allocated is greater than the threshold, repeating said steps of re-calculating, ordering, setting and determining.

In this manner, even when a large population of users exist, each with many services, the number of messages required to allocate the overall resource is limited to a manageable number. It is noteworthy that a single user with multiple services, each allocated resource, will only result in a single allocation message. However, by having large numbers of users with large numbers of services the chance of allocating a small amount of resource to many users is increased.

