WO2013107379A1 - Procédé, station de base, terminal et système de travail de coopération entre un wlan et un réseau cellulaire - Google Patents

Procédé, station de base, terminal et système de travail de coopération entre un wlan et un réseau cellulaire Download PDF

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Publication number
WO2013107379A1
WO2013107379A1 PCT/CN2013/070670 CN2013070670W WO2013107379A1 WO 2013107379 A1 WO2013107379 A1 WO 2013107379A1 CN 2013070670 W CN2013070670 W CN 2013070670W WO 2013107379 A1 WO2013107379 A1 WO 2013107379A1
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WO
WIPO (PCT)
Prior art keywords
wlan
terminal
information
base station
access
Prior art date
Application number
PCT/CN2013/070670
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English (en)
Chinese (zh)
Inventor
谢芳
胡南
胡臻平
Original Assignee
***通信集团公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ***通信集团公司 filed Critical ***通信集团公司
Publication of WO2013107379A1 publication Critical patent/WO2013107379A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W48/00—Access restriction; Network selection; Access point selection
    • H04W48/08—Access restriction or access information delivery, e.g. discovery data delivery
    • H04W48/12—Access restriction or access information delivery, e.g. discovery data delivery using downlink control channel
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/12—Wireless traffic scheduling
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks
    • H04W84/042—Public Land Mobile systems, e.g. cellular systems
    • H04W84/045—Public Land Mobile systems, e.g. cellular systems using private Base Stations, e.g. femto Base Stations, home Node B

Definitions

  • the present invention relates to the field of wireless communication technologies, and in particular, to a method, a base station, a terminal, and a system for a wireless local area network and a cellular network to work together.
  • Background technique
  • Wireless Local Area Network has been considered as an important means of offloading cellular network services due to its operation in the 2.4GHz free band, low cost, easy deployment, and high data rate.
  • the use of WLAN networks to offload cellular network services, especially low-value services such as streaming web browsing and instant messaging (such as QQ and MSN), can effectively reduce the burden on the cellular network, improve indoor coverage, and provide high-speed access, thereby enhancing the user experience.
  • the Access Network Discovery and Selection Function is a network element defined by the 3GPP for accessing network discovery, and provides a network selection policy (including related information for access network discovery and selection) for the terminal.
  • the network selection policy may include network information such as available WLAN, Worldwide Interoperability for Microwave Access (Wimax), the type of network that is preferentially accessed, and even the network identifier of the preferential access (such as the service set identifier of the WLA). (Service Set Identifier, SSID), working channel, etc., and conditions and charging policies for which the network selection policy applies and is disabled.
  • the manager client in the terminal is composed of a policy acquisition module, a policy matching module, a policy execution module, an automatic authentication module, and the like, and the client determines whether the terminal should access the cellular network or the WLAN according to the obtained network selection policy.
  • the communication protocol standard between the AKDSF and the terminal is based on the Open Mobile Alliance Device Management (OMA-DM) framework.
  • the method for offloading cellular network services by using WLAN is that the terminal determines whether the service should be connected to the WLAN or the cellular network according to the type of service initiated and the network selection policy.
  • the cellular network and the WLAN work independently. Each time the terminal decides to access the WLAN, it must search the network, receive a beacon frame (Beacon), or send a probe frame to randomly try to access an access point (Access Point). , ⁇ ), sometimes it may take several attempts to successfully access the ⁇ , which takes a long time and wastes system resources and affects the user's business experience.
  • the embodiments of the present invention provide a method, a base station, a terminal, and a system for a WLAN and a cellular network to work together to improve the speed at which a terminal accesses a WLAN.
  • a method for a wireless local area network WLAN and a cellular network to work together comprising:
  • the base station determines that the terminal should access the WLAN
  • the base station determines deployment information of the WLAN
  • the base station determines the WLAN scheduling information according to the determined deployment information of the WLAN, and sends the WLAN scheduling information to the terminal through the physical downlink control channel PDCCH of the cellular network.
  • a base station, the base station includes:
  • a first determining unit configured to determine that the terminal should access the wireless local area network WLAN
  • a second determining unit configured to determine deployment information of the WLAN
  • a sending unit configured to determine WLAN scheduling information according to the determined deployment information of the WLAN, and send WLAN scheduling information to the terminal by using a physical downlink control channel PDCCH of the cellular network.
  • a method for a wireless local area network WLAN and a cellular network to work together comprising:
  • a terminal, the terminal includes:
  • a receiving unit configured to receive wireless local area network WLAN scheduling information that is sent by the base station through a physical downlink control channel PDCCH of the cellular network;
  • An access unit configured to access the WLAN according to the WLAN scheduling information.
  • the base station is configured to determine that the terminal should access the WLAN, determine the deployment information of the WLAN, determine the WLAN scheduling information according to the determined deployment information of the WLAN, and send the WLAN scheduling information to the terminal by using the physical downlink control channel PDCCH of the cellular network;
  • the terminal is configured to receive wireless local area network WLAN scheduling information that is sent by the base station through the physical downlink control channel PDCCH of the cellular network, and access the WLAN according to the WLAN scheduling information.
  • the base station when determining that the terminal should access the WLAN, determines the deployment information of the WLAN when determining that the WLAN needs to be used to offload the cellular network service, and adopts the frequency of the WLAN operation as a subcarrier.
  • the PDCCH is used to perform cross-carrier scheduling on the WLAN, and the terminal can access the WLAN according to the WLAN scheduling information sent by the base station through the PDCCH, thereby avoiding the existence of the terminal in determining the access to the WLAN in the prior art.
  • the problem of long access time and wasted system resources increases the speed at which the terminal accesses the WLAN.
  • FIG. 1 is a schematic diagram of a terminal network selection architecture based on an operator policy defined by the 3GPP in the prior art
  • FIG. 2 is a schematic flowchart of a method for working in cooperation between a WLAN and a cellular network according to Embodiment 1 of the present invention
  • FIG. 3 is a schematic structural diagram of a base station according to Embodiment 2 of the present invention
  • FIG. 4 is a schematic structural diagram of a terminal according to Embodiment 3 of the present invention.
  • FIG. 5 is a schematic structural diagram of a system in which a WLAN and a cellular network work in cooperation according to Embodiment 4 of the present invention. detailed description
  • LTE-Advanced LTE-Advanced
  • LTE-A Long Term Evolution-Advanced
  • Carrier Aggregation is based on the principle of combining two or more basic carriers to meet higher bandwidth requirements. After the carrier aggregation technology is introduced, the number of working carriers in one cell is changed from one to multiple, forming a multi-carrier communication scenario.
  • the solution provided by the embodiment of the present invention is based on the carrier aggregation technology.
  • the base station determines that the WLAN is to be used to offload the cellular network service
  • the frequency of the WLAN operation is used as a subcarrier to perform cross-carrier scheduling on the WLAN.
  • a first embodiment of the present invention provides a method for working in cooperation between a WLAN and a cellular network.
  • the process of the method is as shown in FIG. 2, and includes:
  • Step 101 The base station determines whether access to the WLAN is required.
  • the base station can determine whether it is necessary to use the WLAN to offload the cellular network service, and determine that the terminal should access the WLAN when it is determined that the WLAN is used to offload the cellular network service.
  • the base station may, but is not limited to, determine whether the terminal should access the WLAN by using a service type to be executed in the terminal.
  • the service to be executed in the terminal is an instant communication service. For example, when the QQ chats, it is determined that the service needs to be offloaded by the WLAN, that is, the terminal should be connected to the WLAN.
  • Step 102 The base station determines deployment information of the WLAN.
  • the deployment information of the WLAN can be simply understood as the map information of the WLAN AP.
  • the information can be stored centrally in a certain network element.
  • the WLAN AP map information of Haidian District is stored in the network management.
  • the base station can determine the deployment information of the WLAN in any of the following three ways:
  • Method 1 When determining that the terminal should access the WLAN, the base station initiates a request to the network element that saves the deployment information of the WLAN. And obtaining the deployment information of the WLAN sent by the network element as the determined deployment information of the WLAN.
  • the second method is: the base station receives the deployment information of the WLA periodically sent by the network element, and the distance determining terminal should access
  • the deployment information of the WLAN received by the WLAN at the time of the WLAN is used as the deployment information of the determined WLAN.
  • the third method is: when the base station receives the deployment information of the updated WLAN when the deployment information of the saved WLAN is updated, The deployment information of the updated WLAN received at the latest time when the terminal should access the WLAN is determined as the deployment information of the determined WLAN.
  • Step 103 The base station performs cross-carrier scheduling.
  • the base station can use the frequency of the AP as a subcarrier to perform cross-carrier scheduling on the WLAN.
  • the step 103 may include: determining, by the base station, the WLAN scheduling information according to the determined deployment information of the WLAN, and transmitting the WLAN scheduling information to the terminal by using a Physical Downlink Control Channel (PDCCH) of the cellular network.
  • PDCCH Physical Downlink Control Channel
  • the information carried by the PDCCH of the existing LTE system includes one or more of the following information:
  • the PDCCH can be classified into 10 types in the prior art.
  • a new PDCCH format is proposed, and the base station uses the format to implement carrier aggregation. The way to cross-carrier scheduling of WLAN networks.
  • the information carried in the new PDCCH format (that is, the WLAN scheduling information sent by the PDCCH) provided in this embodiment may include information indicating that the current scheduling is a WLAN carrier, and an SSID corresponding to the WLAN indicating the terminal access, indicating the terminal connection.
  • the information carried in the new PDCCH format may include information indicating that the current scheduling is a WLAN carrier, an SSID corresponding to the WLAN indicating the terminal access, a working channel of the WLAN indicating the terminal access, and access to the WLAN.
  • the capabilities of the terminal require information for all four types of information.
  • any one of the remaining three types of bit combinations in the three reserved bits (bits) of the carrier indication field CIF introduced by the enhanced long-term evolution (LTE-AR10) of the tenth version may be used to indicate the current scheduling.
  • the SSID corresponding to the WLAN indicating the terminal access may occupy 16 bits;
  • the working channel of the WLAN indicating the terminal access can occupy 4 bits
  • the working channel of the WLAN indicating the terminal access can occupy 2 bits
  • the capability requirement information for the terminal accessing the WLAN can occupy 16 bits.
  • the capability requirements for the terminal may include, but are not limited to, at least one of the following: support for polling, support for Density Parity Check Code (LDPC), and support for transmitting space-time block codes (Space-Time Block Coding) , STBC), support for receiving STBC, etc.
  • LDPC Density Parity Check Code
  • STBC Space-Time Block Coding
  • Step 104 The terminal receives the WLAN scheduling information.
  • the terminal may receive WLAN scheduling information sent by the base station through the PDCCH of the cellular network.
  • Step 105 The terminal accesses the WLAN.
  • the terminal may access the WLAN according to the WLAN scheduling information.
  • the terminal may determine, according to the capability requirement information of the terminal that accesses the WLAN in the WLAN scheduling information, first, whether it meets the capability requirement of the terminal, and when it is determined that the capability requirement of the terminal is not met, the terminal does not need to try to connect. Into the WLAN.
  • the base station determines whether the terminal needs to access the WLAN, and when determining that the terminal needs to access the WLAN, performs cross-carrier scheduling on the WLAN to improve the speed at which the terminal accesses the WLAN. Further, the first embodiment provides at least three ways for the base station to obtain the deployment information of the WLAN, improves the flexibility of the base station to obtain the deployment information of the WLAN, and defines a new PDCCH format for carrying the WLAN scheduling information.
  • a second embodiment of the present invention provides a base station.
  • the structure of the base station is as shown in FIG. 3, and includes:
  • the first determining unit 11 is configured to determine that the terminal should access the WLAN; the second determining unit 12 is configured to determine the deployment information of the WLAN; the sending unit 13 is configured to determine the WLAN scheduling information according to the determined deployment information of the WLAN, and The PDCCH transmits WLAN scheduling information to the terminal.
  • the second determining unit 12 is specifically configured to determine deployment information of the WLAN by using any one of the following three methods: When determining that the terminal should access the WLA, the device sends a request to the network element that saves the deployment information of the WLAN, and uses the received deployment information of the WLAN sent by the network element as the determined deployment information of the WLAN;
  • a third embodiment of the present invention provides a terminal.
  • the structure of the terminal is as shown in FIG. 4, and includes:
  • the receiving unit 21 is configured to receive wireless local area network WLAN scheduling information that is sent by the base station through the PDCCH of the cellular network;
  • the access unit 22 is configured to access the WLAN according to the WLAN scheduling information.
  • Embodiment 4 of the present invention provides a system in which a WLAN and a cellular network work together.
  • the structure of the system may be as shown in FIG. 5, including a base station 31 and a terminal 32, where:
  • the base station 31 is configured to determine that the terminal should access the WLAN, determine the deployment information of the WLAN, determine the WLAN scheduling information according to the determined deployment information of the WLAN, and send the WLAN scheduling information to the terminal through the physical downlink control channel PDCCH of the cellular network;
  • the terminal 32 is configured to receive wireless local area network WLAN scheduling information that is sent by the base station through a physical downlink control channel PDCCH of the cellular network, and access the WLAN according to the WLAN scheduling information.
  • embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.
  • a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.
  • These computer program instructions can also be stored in a particular computer capable of booting a computer or other programmable data processing device In a computer readable memory that operates in a computer readable memory, causing instructions stored in the computer readable memory to produce an article of manufacture comprising instruction means implemented in a block or in a flow or in a flow chart and/or block diagram of the flowchart The functions specified in the boxes.
  • These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Selon un mode de réalisation, la présente invention concerne un procédé, une station de base, un terminal et un système de travail de coopération entre un WLAN et un réseau cellulaire, comprenant les étapes suivantes : détermination d'informations de déploiement de WLAN lorsqu'une station de base détermine qu'un terminal doit accéder à un WLAN, c'est-à-dire lorsque le WLAN est déterminé comme étant nécessaire pour un partage de service de réseau cellulaire ; utilisation d'un point de fréquence de fonctionnement de WLAN en tant que sous-porteuse ; utilisation, à la manière d'une agrégation de porteuses, du PDCCH du réseau cellulaire pour effectuer une planification inter-porteuses pour le WLAN ; et accès au WLAN par le terminal, conformément aux informations de planification de WLAN transmises par la station de base par le biais du PDCCH, en évitant ainsi les problèmes de temps d'accès long et de gaspillage de ressources de système à l'état antérieur de la technique lorsque le terminal est déterminé comme devant accéder au WLAN, et en améliorant ainsi la vitesse d'accès au WLAN par le terminal.
PCT/CN2013/070670 2012-01-18 2013-01-18 Procédé, station de base, terminal et système de travail de coopération entre un wlan et un réseau cellulaire WO2013107379A1 (fr)

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CN201210015604.4 2012-01-18
CN201210015604.4A CN103220786B (zh) 2012-01-18 2012-01-18 Wlan和蜂窝网络协同工作的方法、基站、终端和***

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