KR20110047984A - How to handle proximity information transmissions and related communication devices - Google Patents

Abstract

PURPOSE: A method of handling proximity information transmission is provided to successively perform an inbound movement to a closed subscriber group cell. CONSTITUTION: A method of handling proximity information transmission for a mobile device includes a CSG(Closed Subscriber Group) whitelist capable of providing a list of accessible CSG cells in a wireless communication system(410). The method comprises sending the proximity information to a network of the wireless communication system when a CSG cell in the CSG whitelist is detected, and resending the proximity information to the network when the proximity information is not received by the network(420).

Description

Method of handling proximity information transmission and related communication device

Cross Reference to Related Application

This application is filed on October 30, 2009, entitled "Methods to transmit proximity indication information in wireless communications system," and US Patent Application No. 61 / 256,317, entitled "Methods to report proximity indication information after handover in wireless communications system." Priority is claimed by US Provisional Application No. 61 / 290,890, filed December 30, 2009, the contents of which are hereby incorporated by reference.

TECHNICAL FIELD The present application relates to a method used in a wireless communication system and a communication device thereof, and more particularly, to a method for processing proximity information transmission in a wireless communication system and a related communication device.

Long-term evolution (LTE) systems, initiated by the Third Generation Joint Project (3GPP), currently provide new radio interfaces that provide high data rates, low latency, packet optimization, and improved system capacity and coverage; It is considered as a radio network architecture. In LTE systems, an evolved universal terrestial radio access network (E-UTRAN) comprises a plurality of evolved Node Bs (eNBs) and communicates with a plurality of mobile stations, also called user equipments (UEs). do.

In an LTE system, a UE that supports closed subscirber group (CSG) characteristics is an inbound move (ie handover) to a CSG / hybrid cell when the UE is configured for proximity indication reporting by the network. Proximity information can be sent to the network to start up. A UE supporting the CGS feature has a CSG whitelist that includes one or more CSG IDs associated with CSG cells that allow the UE to access. While the CSG cell is coupled with a narrow coverage base station that can be used for great benefits such as high bandwidth wireless Internet access in homes and offices, and efficient and cost effective capacity solutions for indoor applications, hybrids The cell is accessed as a CSG cell by a UE with a CSG whitelist containing its CSG ID and as a normal cell by all other UEs.

Regarding the operation for inbound mobility, when the UE enters near a cell with a CSG ID that is in the CSG whitelist of the UE, proximity information is sent to the network (ie, E-UTRAN, eNB, or base station). The network configures the UE to make a measurement configuration that includes a measurement gap if needed after proximity information is received. The UE performs measurements on the CSG cell to generate a measurement report to the network in preparation for handover. In addition, the network may configure the UE to perform system information (SI) reporting. After the UE reads the CSG cell's system information, it sends an SI report containing the CSG cell's CSG ID to the network, so that the network is allowed to access the CSG cell based on that CSG ID and the UE's CSG whitelist. Allows you to check whether or not. In other words, the network determines whether to handover the UE to the CSG cell according to the measurement report and the SI report, and sends a handover command to the UE when the network decides to handover the UE to the CSG cell.

In addition, after transmitting "entering" proximity information to the network, if it is determined that the UE is no longer close to the entered CSG cell, the UE should send the "leaving" proximity information to the network. Otherwise, the network does not know that the UE has left, and will ask the UE to perform measurements on the CSG cell that has left, which will cause a waste of radio resources.

However, due to the ambiguous specification for proximity information transmission of the LTE system, the UE cannot perform inbound movement to the CSG / hybrid cell. In addition, several scenarios can be described as follows.

As a first scenario, proximity information sent by the UE may not be received by the network due to handover or RRC connection reestablishment procedure (caused due to radio link failure, RLC non-return error, MAC random access error, etc.). If proximity information is not received by the network, inbound movement to CSG / hybrid cells cannot begin because the network does not know whether the UE enters near CSG cells in the UE's CSG whitelist. Thus, the user of the UE will complain why the UE cannot use the CSG cell to communicate with. Details related to the inbound movement operation can be referred to from the above description, and thus will be omitted here.

The second scenario is after the UE connects to the first eNB and enters the vicinity of the cells with CSG IDs in the CSG whitelist of the UE. As such, the UE sends an access indication to the first eNB for inbound movement. Meanwhile, the first eNB sends a handover command to the UE and instructs the UE to handover to the second eNB. In addition, the handover command enables proximity indication reporting, allowing the UE to send proximity information to the second eNB. However, after the UE is handed over to the second eNB, the UE is still near the cells. That is, the UE does not leave near the cells even after handing over to the second eNB. In this situation, the UE never transmits proximity information since the UE never leaves near the cells. Therefore, the second eNB does not know whether the UE is near the cells, and thus cannot handover the UE to any CSG cell or set up system information (SI) reporting of the UE.

In addition, the UE connected to the first eNB is configured to perform SI reporting. The UE sends an SI report containing the CSG ID to the network, allowing the network to determine whether the CSG cell is allowed access according to the CSG ID. However, after the UE is handed over to the second eNB, the UE does not send an SI report because the SI reporting configuration from the first eNB is removed. As a result, the second eNB does not receive the SI report from the UE and thus cannot handover the UE to the CSG cell.

In addition, the above-described situation may occur in a universal mobile telecommunications system (UMTS). For example, when a UE approaches or leaves a CSG / Hybrid cell with a CSG ID in its CSG whitelist, the UE provides proximity information to the serving radio network controller (SRNC). Due to similar trends in the UMTS system, the problems described above arise as well.

An object of the present invention is to provide a method and a related communication device for processing proximity information transmission in a wireless communication system in order to solve the above problems.

The present invention will disclose a method of processing proximity information transmission for a mobile device having a CSG whitelist capable of providing a list of closed subscriber group (CSG) cells accessible in a wireless communication system. The method includes transmitting proximity information to a network of a wireless communication system when one CSG cell on the CSG whitelist is detected, and sending the proximity information to the network when the proximity information is not received by the network. Retransmitting.

The present invention discloses a method of processing proximity information transmission for a mobile device having a CSG white list capable of providing a list of accessible CSG cells in a wireless communication system. The method includes transmitting proximity information to a first base station of a wireless communication system when entering near CSG cells on a CSG whitelist, and making a connection transfer from the first base station to a second base station of the wireless communication system. Performing, and retransmitting the proximity information to the second base station if it is staying adjacent to the CSG cells on the CSG whitelist after the connection change is complete.

The present invention discloses a method for processing proximity information for a first base station of a wireless communication system. The method includes receiving proximity information from a mobile device in a wireless communication system, and when the mobile device attempts to change its connection from a first base station to a second base station, near the CSG cells in the CSG whitelist included in the mobile device. Signaling to the second base station of the wireless communication system that the mobile device is entering.

The present invention discloses a communication device of a wireless communication system for processing proximity information transmission. The communication device includes a CSG whitelist capable of providing a list of accessible CSG cells, means for transmitting proximity information to a network of a wireless communication system when a CSG cell in the CSG whitelist is detected, and proximity Means for retransmitting proximity information to the network when the information is not received by the network.

The present invention discloses a communication device of a wireless communication system for processing proximity information transmission. The communication device includes a CSG whitelist capable of providing a list of accessible CSG cells, and means for transmitting proximity information to the first base station of the wireless communication system when entering the vicinity of the CSG white cells in the CSG whitelist; Means for performing a connection change from the first base station to the second base station of the wireless communication system, and means for retransmitting the proximity information to the second base station when the connection change continues after staying in close proximity to the CSG cells in the CSG whitelist.

The present invention discloses a first base station of a wireless communication system for processing proximity information transmission. The first base station is provided with means for receiving proximity information from the mobile device of the wireless communication system, and when the mobile device attempts to change the connection from the first base station to the second base station, the first base station is in close proximity to the CSG cells in the CSG whitelist included in the mobile device. Means for signaling to a second base station of the wireless communication system that it is entering.

These and other objects of the present invention will no doubt become apparent after reading the following detailed description of the preferred embodiments illustrated in the accompanying drawings by those skilled in the art.

According to the present invention, a method and a related device for processing proximity information transmission are provided so that an inbound movement to a CSG cell can be successfully performed even when a connection change occurs.

1 shows a schematic diagram of a typical wireless communication system.
2 shows a schematic diagram of a typical communication device.
3 shows a schematic diagram of communication protocol layers of a typical communication system.
4-6 are flow diagrams of typical processes.

Reference is made to FIG. 1, which is a schematic diagram of a wireless communication system 10 according to one example. In short, the wireless communication system 10 consists of one network terminal and a plurality of user equipments (UEs). The wireless communication system 10 may be a Universal Mobile Telecommunications System (UMTS), a long-term evolution (LTE) system, or some other similar network system. In an LTE system, a network refers to an evolved-UTRAN (EUTRAN) that includes a plurality of eNBs or a core network entity (eg, a Mobility Management Entity called an MME), and mobile devices refer to user equipments (UEs). UEs may be devices such as mobile telephones, computer systems, etc. This term will be used throughout the entire document for easy reference, but it is to be understood that this disclosure is limited to any one particular type of network. In some examples, the network and the UE may be considered either a transmitter or a receiver depending on the direction of transmission, for example, in uplink (UL), the UE is a transmitter and the network is a receiver, In the downlink (DL), the network becomes the transmitter and the UE becomes the receiver.

2 shows a schematic diagram of a typical communication device 20. The communication device 20 may be, but is not limited to, the mobile device 10 shown in FIG. 1. The communication device 20 may comprise a processing means 20, such as a microprocessor or an application specific integrated circuit (ASIC), a storage unit 210 and a communication interface unit 220. The storage unit 210 can be any data storage device capable of storing program code 214 to be accessed by the processing means 200. Examples of storage unit 210 include, but are not limited to, subscriber identity module (SIM), ROM (ROM), flash memory, random-access memory (RAM), CD-ROM, magnetic tape, hard disk, And optical data storage devices. The communication interfacing unit 220 is preferably a radio transceiver and can exchange radio signals with the network according to the processing result of the processing means 2000.

3 shows a schematic diagram of communication protocol layers of an LTE system. Aspects of some of the protocol layers may be defined in program code 214 and executed by processing means 200. The protocol layers are from top to bottom radio resource controller (RRC) layer 300, packet data convergence protocol (PDCP) layer 310, radio link control (RLC) layer 320, Medium Access Control (MAC) Layer 330 and Physical (PHY) Layer 340. The RRC layer 300 is used to perform RRC connection management, measurement control, handover, and radio bearer (RB) control, which is responsible for creating and terminating radio bearers (RBs). Before the source eNB handovers the mobile device to the target eNB in the network of FIG. 1, the source eNB to the target eNB / MME, a HANDOVER REQUEST message for conveying information necessary to prepare for handover of the UE. Issue a. After the target eNB / MME prepares for handover and sends a HANDOVER REQUEST ACKNOWLEDGE / HANDOVER COMMAND to the source eNB, it must be aware that the source eNB can handover the UE to the target eNB. . This process will be referred to as handover preparation process from now on.

4 shows a flow diagram of a typical process 40. This process 40 is used to handle proximity information transmission within the UE, the mobile device of FIG. The UE has a CSG whitelist that can provide a list of accessible CSG (closed subscriber group) cells. This process 40 can be compiled into program code 214 and includes the following steps:

Step 400: Start.

Step 410: When a CSG cell in the CSG whitelist is detected, transmit proximity information to a network of the wireless communication system.

Step 420: When the proximity information is not received by the network, retransmit the proximity information to the network.

Step 430: Exit.

According to the process 40, the UE retransmits proximity information to the network when previous neighbor information was not successfully sent to the network. For example, the UE transmits proximity information to the network, but does not receive an acknowledgment (eg, RLC ACK) for confirmation of the proximity information transmission. The UE will then send proximity information back to the network. In addition, the UE may not successfully transmit proximity information due to a handover procedure or an RRC connection reconfiguration procedure. In this situation, the UE retransmits proximity information after handover or RRC connection reconfiguration is completely performed.

The process 40 clearly specifies how the UE will handle proximity information transmission failure. The UE retransmits the proximity information to the network when the network has not received the proximity information, thereby recognizing that the network enters the proximity of the cells with the CSG IDs in the CSG whitelist from that proximity information and accordingly sends the UE to the CSG. Allow handover to the cell. As the proximity information retransmission mechanism is clearly defined here, it is possible to increase the reliability of the proximity information transmission.

5 illustrates a flowchart of a typical process 50. This process 50 is used to handle proximity information transmissions within the UE, the mobile device of FIG. The UE has a CSG whitelist that can provide a list of accessible CSG (closed subscriber group) cells. This process 50 can be compiled into program code 214 and includes the following steps:

Step 500: Start.

Step 510: When entering a CSG cell in the CSG whitelist, transmitting proximity information to the first base station of the wireless communication system.

In step 520, a connection change is performed from the first base station to the second base station of the wireless communication system.

Step 530: Remaining near the CSG cells in the CSG whitelist after the connection change is completed, retransmit the proximity information to the second base station.

Step 540: End.

According to the process 50, after the UE moves to the second base station, the UE retransmits the proximity information to the second base station if the UE did not leave near the detected CSG cells before the connection change. The connection change may be a handover procedure or an RRC connection reset procedure. In other words, after the UE completely performs the handover procedure or the RRC connection reestablishment procedure to change the connection from the first base station to the second base station, the UE retransmits the proximity information to the second base station if it stays near the CSG cells. . Accordingly, the second base station may recognize from the proximity information that the UE enters the vicinity of the CSG cells and, accordingly, may set the UE to handover the UE to one CSG cell or perform system information (SI) reporting.

Based on the process 50, the following example is given. The UE connects to the source eNB and is configured to perform proximity indication reporting by the source eNB. Upon entering the vicinity of cells with CSG IDs in the CSG whitelist of the UE, the UE sends first proximity information (eg, “entering proximity information”) to the source eNB, while the source eNB handovers. Handover the UE to the target eNB via the command The handover command enables proximity indication reporting to the target eNB, allowing the UE to send proximity information to the target eNB after the handover procedure. After being over, when the UE still enters the vicinity of the CSG cells (ie, when the UE never leaves near the whole of the CSG cells), the UE sends the first proximity information to the target eNB. Since the UE recognizes from the first proximity information that the UE enters the vicinity of the CSG cells, the target eNB may hand over the UE to one CSG cell or configure the UE to perform SI reporting.

In addition, after the UE is handed over to the target eNB, when the UE leaves near the CSG cells (ie, when the UE leaves near all of the CSG cells), the UE accesses second proximity information (eg, “leaving”). Send the information to the target eNB, whereby the target eNB becomes aware that the UE is leaving the vicinity of the CSG cells, thus causing unnecessary actions on the UE (eg, handing the UE over to one CSG in the CSG whitelist). The UE should know that the UE sends the second proximity information to the target eNB only if the source eNB signals to the target eNB that the UE is entering the vicinity of the CSG cells. Since the eNB does not know that the UE is entering the vicinity of the CSG cells, the UE does not need to transmit the second proximity information to the target eNB, thereby reducing the transmission power entering the second proximity information. Established by the source eNB Eliminates the configuration settings for defined proximity indication reporting, so that the UE does not send proximity information to the target eNB after handover until the UE enters near cells with CSG IDs in the CSG whitelist. Do not.

6 shows a flow diagram of a typical process 60. This process 60 is used to handle proximity information transmission within the network (eg, eNB or base station) of FIG. 1. This process 60 can be compiled into the program code 214 and includes the following steps:

Step 600: Start.

Step 610: Receive proximity information from the UE of the wireless communication system.

Step 620: During the handover preparation procedure, when the UE attempts to change the connection from the first base station to the second base station, to the second base station of the wireless communication system, the UE near the CSG cells in the CSG whitelist included in the UE Signaling that is entering.

Step 630: End.

According to the process 60, the second base station is informed by the first base station that the UE is entering the vicinity of the CSGs when the UE performs a connection change from the first base station to the second base station. Accordingly, the second base station knows that the UE is in the vicinity of the CSG cells, and accordingly, the second base station can configure the UE to perform SI reporting or hand over the UE to one CSG cell.

Based on the process 60, the following example is given. The UE is connecting to the source eNB and is set to perform proximity indication reporting by the source eNB. When entering the vicinity of cells with CSG IDs in the CSG whitelist of the UE, the UE sends the first proximity information to the source eNB. Before the source eNB hands over the UE to the target eNB (ie, during the handover preparation procedure), the source eNB signals to the target eNB that the UE enters near the CSG cells. Thus, after the UE is handed over to the target eNB, the target eNB knows that the UE is near the CSG cells from the source eNB, so that the target eNB reports the proximity indication reporting, SI reporting, or hand of the UE to one CSG cell. Over can be set. In addition, the source eNB may signal SI reporting configuration to the target eNB during the handover preparation procedure. For example, the UE sends an SI report to the source eNB after connecting to the source eNB. Before the source eNB hands over the UE to the target eNB, the source eNB signals information about the SI report to the target eNB. The target eNB then knows from the source eNB that the UE enters the vicinity of the CSG cells and can thus establish proximity indication reporting, SI reporting, or handover of the UE to the CSG cell.

The steps of the processes described above, including the proposed steps, may be hardware, firmware known as a combination of computer instructions and data residing as hardware device and read-only software of hardware device, or means that may be an electronic system. It should be understood that they may be implemented by them. Examples of hardware may be analog, digital and synthetic circuits known as microcircuits, microchips, or silicon chips. Examples of electronic systems may include a system on chip (SOC), a system in package (Sip), a computer on module (COM), and a communication device 20.

In conclusion, typical examples and configurations have been proposed to handle successful transmission of the UE's proximity information when a connection change (eg, handover or RRC connection reestablishment procedure) occurs to successfully perform inbound movement to the CSG cell.

Those skilled in the art will appreciate that numerous modifications and substitutions can be made to the devices and methods of the present invention while maintaining the teachings thereof. Accordingly, the above disclosure should be construed as limited only by the scope of the appended claims.

Claims (18)

A method of processing proximity information of a mobile device having a CSG white list capable of providing a list of closed subscriber groups (CSGs) accessible in a wireless communication system, the method comprising:
Transmitting proximity information to a network of the wireless communication system when a CSG cell in the CSG whitelist is detected; And
Resending the proximity information to the network when the proximity information is not received by the network. The method of claim 1, wherein retransmitting the proximity information to the network when the proximity information is not received by the network,
Retransmitting the proximity information when the proximity information is not received by the network due to a handover procedure or a radio resouce control (RRC) connection reestablishment procedure. The method of claim 1, wherein retransmitting the proximity information to the network when the proximity information is not received by the network,
Retransmitting the proximity information to the network when an acknowledgment (ACK) for proximity information confirmation is not received. A method of processing proximity information of a mobile device having a CSG white list capable of providing a list of closed subscriber groups (CSGs) accessible in a wireless communication system, the method comprising:
Transmitting proximity information to a first base station of the wireless communication system when entering a vicinity of CSG cells in the CSG whitelist;
Performing a connection change from the first base station to a second base station of the wireless communication system; And
Retransmitting the proximity information to the second base station when staying near the CSG cells in the CSG whitelist even after the connection change is complete. The method of claim 4, wherein the performing of the connection change from the first base station to the second base station of the wireless communication system comprises:
And performing a handover procedure or an RRC resetting procedure to change from the first base station to the second base station. The method of claim 4, wherein
After the connection change is completed, when leaving the CSG cells in the whitelist and when the first base station signals to the second base station that the mobile device enters the CSG cells in the CSG whitelist. And transmitting the proximity information to the second base station. The method of claim 4, wherein
After the connection change is completed, when leaving the CSG cells in the whitelist and when the first base station does not signal that the mobile device enters the CSG cells in the CSG whitelist to the second base station. And not transmitting the second proximity information to the second base station. A method for processing proximity information of a first base station in a wireless communication system,
Receiving proximity information from a mobile device of the wireless communication system; And
When the mobile device attempts to change the connection from the first base station to the second base station, signaling to the second base station that the mobile device enters the vicinity of the CSG cells in the CSG whitelist. How to. The method of claim 8,
When the mobile device attempts to change the connection from the first base station to the second base station, signaling a system information reporting configuration to a second base station of the wireless communication system. How to feature. A communication device in a wireless communication system having a CSG whitelist capable of providing a list of accessible closed subscriber groups (CSGs) and handling proximity information transmission, the communication device comprising:
Means for transmitting proximity information to a network of the wireless communication system when a CSG cell in the CSG whitelist is detected; And
Means for retransmitting the proximity information to the network when the proximity information is not received by the network. The apparatus of claim 10, wherein the means for retransmitting the proximity information to the network when the proximity information is not received by the network,
Means for retransmitting the proximity information when the proximity information is not received by the network due to a handover procedure or a radio resouce control (RRC) connection reestablishment procedure. The apparatus of claim 10, wherein the means for retransmitting the proximity information to the network when the proximity information is not received by the network,
Means for retransmitting the proximity information to the network when an acknowledgment for acknowledgment of proximity information transmission is not received. A communication device of a wireless communication system having a CSG white list capable of providing a list of accessible closed subscriber groups (CSGs) and processing proximity information of a mobile device, the communication device comprising:
Means for transmitting proximity information to a first base station of the wireless communication system when entering a vicinity of CSG cells in the CSG whitelist;
Means for performing a connection change from the first base station to a second base station of the wireless communication system; And
And means for retransmitting the proximity information to the second base station when staying near the CSG cells in the CSG whitelist even after the connection change is complete. The apparatus of claim 13, wherein the means for performing a connection change from the first base station to a second base station of the wireless communication system,
Means for performing a handover procedure or an RRC resetting procedure to change from the first base station to the second base station. The method of claim 13,
After the connection change is completed, when leaving the CSG cells in the whitelist and when the first base station signals to the second base station that the mobile device enters the CSG cells in the CSG whitelist. 2 means for transmitting the proximity information to the second base station. The method of claim 13,
After the connection change is completed, when leaving the CSG cells in the whitelist and when the first base station does not signal that the mobile device enters the CSG cells in the CSG whitelist to the second base station. And means for transmitting no second proximity information to the second base station. In the first base station of a wireless communication system for processing proximity information,
Means for receiving proximity information from a mobile device of the wireless communication system; And
Means for signaling to the second base station that the mobile device enters a vicinity of CSG cells in a CSG whitelist when the mobile device attempts to change the connection from the first base station to a second base station. First base station. The method of claim 17,
Means for signaling a system information reporting configuration to a second base station of the wireless communication system when the mobile device attempts to change the connection from the first base station to the second base station. Characterized by a first base station.

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