KR20100126631A - Entry restriction scheme for femto abs - Google Patents

Abstract

PURPOSE: An entry restriction scheme for femto abs is provided to efficiently perform a communication among macro base station, femto base station and the terminal. CONSTITUTION: A non-member terminal receives a preamble and SFH(Super Frame Header) of the CSG(Closed Subscriber Group) closed femto base station(S601). The terminal transmits the ranging code(S602). The terminal receives a ranging acknowledgement message(S603). In case the ranging state is succeed, the terminal transmits the ranging request message to the femto base station(S604). The femto base station always establishes the CSG cell bar of the ranging response message as 1(S605). The terminal does not attempt to enter into the corresponding femto base station.

Description

Entry restriction scheme of UE in femto base station {Entry restriction Scheme for Femto ABS}

The present invention relates to a broadband wireless access system, and more particularly, to a method and an apparatus for performing the femto base station to effectively limit whether or not the entry of the terminal according to the situation.

A femto base station is a small version of a macro base station, which performs most of the functions of a macro base station, and is a type of base station that may be installed in an area covered by the macro base station or in a shaded area not covered by the macro base station. A femto base station has a network configuration that operates independently and can be installed much more than a relay base station in the city or indoors.

1 is a configuration diagram of a wireless communication system to which a femto base station is added.

As shown in FIG. 1, a wireless communication system to which a femto base station is added includes a femto base station 110, a macro base station, a femto network gateway (FNG) 130, and an access service network. service network (hereinafter referred to as "ASN") 140 and a connectivity service network (hereinafter referred to as "CSN") 150. Macro base station means a general base station of a conventional wireless communication system.

The femto base station 110 operates directly as a macro base station by directly connecting to a transmission control protocol / internet protocol (TCP / IP) network, and has a coverage of about 0.1 to 30 m, and one femto base station 110 can accommodate It is assumed that there are about 10 to 20 terminals. The femto base station 110 may use the same frequency as the macro base station (in the case of intra FA), or may use another frequency (in the case of Inter FA).

The femto base station 110 may be connected to the macro base station through an R1 interface to receive a downlink channel of the macro base station, and the femto base station 110 may transmit a control signal to the macro base station.

The femto base station 110 may cover an indoor or shadowed area that the macro base station does not cover and may support high data transmission. The femto base station 110 may be installed in an overlay form in the macro cell, or may be installed in a non-overlay form in an area not covered by the macro base station.

Femto base station 110 is classified into two types. The first type is a closed subscriber group (CSG) femto base station, and the second type is an open subscriber group (OSG) femto base station. The CSG femto base station may group the terminals accessible to it to grant a CSG ID (identification), and may discriminate when the terminal that has been granted the CSG ID and the terminal that do not access the CSG femtocell base station. The OSG femtocell base station is a base station to which all terminals can access.

The FNG 130 is a gateway controlling the femto base station 110 and may be connected to the ASN 140 and the CSN 150 through the Rx interface and the Ry interface. The femto base station 110 may receive a service from the CSN 150 through the FNG 230, and the terminal connected to the femto base station 110 may provide functions such as authentication and IMS to the FNG 130 or the CSN 150. You can get the service from.

The CSN 150 provides a terminal with a connection of application services such as the Internet and VoIP, and provides authentication and billing functions. The ASN 140 can control the macro base station and manage the connection between the macro base station and the CSN 150. have.

Meanwhile, the above-described CSG type femto base station may be classified into two types according to accessibility of non-member terminals, that is, terminals not received CSG IDs.

CSG-closed femto base station (CSG-Closed Femto ABS) is a type that allows access only to the member terminals. The terminal may store the CSG closed femto base station identifiers allowed for its access in a white list.

On the other hand, CSG open femto base station (CSG-Open Femto ABS) preferentially supports the service to the member terminals, and if the resource is available is a type that allows access to non-member terminals. However, service levels for non-member terminals may be differentiated as compared to member terminals.

As described above for the CSG type femto base station in the mobile communication system using the femto base station, it is assumed that the two types are fixed according to whether or not the non-member terminal is allowed to be connected. This can be seen from the partition information in the Advanced Air Interface System Configuration Descriptor message.

Meanwhile, when the macro base station and the femto base station are installed in the same frequency region, non-member CSG terminals connected to the macro base station may feel interference from neighboring femto base stations. In this case, the macro base station may adjust the interference of the terminal by preventing the femto base station from using a predetermined resource region.

It is an object of the present invention to provide an efficient communication system and communication method.

Another object of the present invention is to provide an efficient communication method for determining whether the femto base station performs access to the femto base station by providing information indicating whether the femto base station is allowed to access the non-member terminal and apparatus for performing the same. It is to provide.

Technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

In a mobile communication system including a macro base station, at least one femto base station, and at least one terminal according to an embodiment of the present invention for solving the above problems, the specific femto base station communication method, the specific femto base station Broadcasting cell type information indicating the CSG femto base station among the Open Subscriber Group (OSG) femto base station and the Closed Subscriber Group (CSG) femto base station; Receiving a first message for attempting to enter a network from a specific terminal; And transmitting a second message including access permission information indicating whether the non-member terminal accesses the specific femto base station to the specific terminal.

In this case, when the specific femto base station is a CSG closed femto base station (CSG Closed Femto ABS), it is preferable that the access permission information is always set to a value that does not allow access of the non-member terminal.

In addition, when the specific femto base station is a CSG open femto base station (CSG Open Femto ABS), it is preferable that the value of the access permission information is determined according to a specific condition. Here, the specific condition may include a resource level available to the specific femto base station or an interference coordination situation of a non-member terminal interfered by the specific femto base station.

In a mobile communication system including a macro base station, at least one femto base station, and at least one terminal according to an embodiment of the present invention for solving the above problems, a method for performing communication by a specific terminal, broadcast from a specific femto base station Receiving cell type information indicating that the CSG femto base station is selected from an Open Subscriber Group (OSG) femto base station and a Closed Subscriber Group (CSG) femto base station; Transmitting a first message for attempting to enter a network to the specific femto base station; Receiving a second message from the specific femto base station including access permission information indicating whether the non-member terminal is allowed to access the specific femto base station; And determining whether to access the specific femto base station according to the value of the access permission information and whether the specific terminal is a member of the specific femto base station.

In this case, when the specific femto base station is a CSG closed femto base station (CSG Closed Femto ABS), the access permission information is always set to a value that does not allow the access of the non-member terminal, the step of determining the specific terminal is Only when a member of a specific femto base station can be performed to determine to connect to the specific femto base station.

In addition, when the specific femto base station is a CSG open femto base station (CSG Open Femto ABS), it is preferable that the value of the access permission information is determined according to a specific condition. Here, the specific condition may include a resource level available to the specific femto base station or an interference coordination situation of a non-member terminal interfered by the specific femto base station.

According to an aspect of the present invention, there is provided a specific terminal apparatus for performing communication in a mobile communication system including a macro base station, at least one femto base station, and at least one terminal; And a radio communication (RF) module for transmitting and receiving a radio signal to and from the outside under the control of the processor. Here, the processor obtains cell type information indicating that the CSG femto base station is broadcasted from a specific femto base station and is an Open Subscriber Group (OSG) femto base station and a Closed Subscriber Group (CSG) femto base station, and attempts to enter a network to the specific femto base station. Transmits a first message for obtaining the access permission information indicating whether to allow access of the non-member terminal to the specific femto base station through a second message received from the specific femto base station; It may be controlled to determine whether to connect to the specific femto base station according to whether the specific terminal device is a member of the specific femto base station.

In this case, when the specific femto base station is a CSG Closed Femto ABS, the access permission information is always set to a value that does not allow access of a non-member terminal, and the processor determines that the specific terminal device is assigned to the specific femto base station. Only when a member of the femto base station can be controlled to access the specific femto base station.

In addition, when the specific femto base station is a CSG open femto base station (CSG Open Femto ABS), it is preferable that the value of the access permission information is determined according to a specific condition. Here, the specific condition may include a resource level available to the specific femto base station or an interference coordination situation of a non-member terminal interfered by the specific femto base station.

In the above embodiments, the first message is a ranging request (AAI_RNG-REQ) message, and the second message is a ranging response (AAI_RNG-RSP) message.

According to the above-described technique, the CSG femto base station can efficiently perform communication between the macro base station, the femto base station, and the terminal by using information indicating whether to permit connection of the non-member terminal.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 is a configuration diagram of a wireless communication system to which a femto base station is added.
FIG. 2 illustrates a method of converting a type to a CSG closed femto base station by the CSG open femto base station according to an embodiment of the present invention, and notifying the terminal of unnecessary network entry (NE) or handover (HO). Figure is shown.
3 is a diagram illustrating a method in which a CSG closed femto base station converts a type to a CSG open femto base station according to an embodiment of the present invention, and notifies the terminal of a network entry (NE) or a handover (HO) of the terminal. One drawing.
FIG. 4 is a diagram for describing a method of a base station prohibiting network entry / handover of non-member terminals without a cell type change using a CSG cell bar according to a resource state of a CSG open femto base station according to another embodiment of the present invention. .
FIG. 5 is a diagram for describing a method in which a femto base station uses the same cell bit as the cell bit used by the macro base station according to another embodiment of the present invention.
FIG. 6 is a diagram illustrating a method in which a CSG closed femto base station restricts access of a non-member terminal using a CSG cell bar bit through a ranging response message according to another embodiment of the present invention.
FIG. 7 is a diagram for describing a method in which a CSG open femto base station restricts access of a terminal using a CSG cell bar bit through a ranging response message according to another embodiment of the present invention.
FIG. 8 is a diagram for describing a method of transmitting an indicator indicating whether a terminal is a member of a corresponding femto base station according to another embodiment of the present invention, and determining whether to permit the access based on the femto base station.
9 is a diagram for describing a method of informing a terminal whether a terminal is a member according to another embodiment of the present invention.
10 is a diagram for briefly describing an apparatus configuration of a terminal, a femto base station, and a macro base station according to embodiments of the present invention.

DETAILED DESCRIPTION Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

Embodiments to be described below will be described with the assumption of a mobile communication system conforming to the IEEE 802.16m standard for convenience of description, but need not be limited thereto. The base station and the terminal according to the IEEE 802.16m system are improved by distinguishing them from legacy systems, for example, a mobile station (MS) and a base station (BS) according to the IEEE 802.16e system. : ABS), Advanced MS (AMS), but in the following description of embodiments of the present invention will be simply described as a base station, a terminal.

In addition, the above-described CSG open femto base station (CSG-Open Fmeto ABS), CSG closed femto base station (CSG-Closed Femto ABS) may be referred to in other terms as long as the non-member terminal can be connected to the CSG femto base station. have.

In addition, as described above, the cell type may be classified through SA-Partitioning information, and information on the SA-Partitioning range may be transmitted through another MAC message (ie, AAI_SCD). For example, in the case of a femto base station, the CSG closed closed femto base station is classified as private, and the OSG femto base station is classified as public, so that the preamble partitioning is performed and corresponding partitioning information is extended to extended system information. Alternatively, cell-selection of a terminal may be supported by a method of delivering through SFH. In addition, the cell bar bit transmitted in the SFH is an indicator representing the accessibility to all base stations.

Based on the above, various embodiments of a communication scheme using a type conversion of a femto base station are described below.

In a mobile communication system including a macro base station, one or more femto base stations, and one or more terminals, a specific femto base station can broadcast whether it is an OSG femto base station or a CSG femto base station through a superframe header (SFH). have. In addition, in case of the CSG femto base station, one of two types (for example, CSG opening / closing) according to the accessibility of the non-member terminal may be broadcasted through an AAI_SCD message.

In addition, the femto base station according to an embodiment of the present invention is configured as a CSG-closed type when serving only a CSG member, and can provide services to non-member terminals when resources of the CSG closed femto base station are free. Assume that the type can be changed to the CSG open femto type. In this case, the femto base station preferably informs the network and the neighbor terminals of the type change.

That is, when the femto base station in the CSG closed mode has sufficient resources, the femto base station changes the mode to the CSG open mode to provide services to non-member terminals (for example, the owner is temporarily visiting the customer through his home CSG femto base station). You can also allow services. In this case, it may be necessary to change the femto type from CSG closure to CSG opening and inform it.

On the contrary, even a CSG open femto base station cannot serve non-members, that is, if there are not enough resources for non-member terminals, it can serve additional CSG members, but later Since the service is not available to the terminals it is necessary to inform the terminal / network.

Whether a CSG femto base station is a CSG open femto base station or a CSG closed femto base station can be generally classified as a 'type', and the CSG femto base station is assigned to the CSG open / closed type at the physical layer according to its operation method. A corresponding preamble cell ID may be allocated. However, when the CSG femto base station changes its cell type according to embodiments of the present invention, it may confuse communication in the physical layer. Therefore, in another embodiment of the present invention, the CSG femto base station may be applied in such a manner that the CSG femto base station only changes the operation 'mode' without changing the cell type (ie, using physically distinguished identifiers or the like). . For example, when the user is initially assigned a preamble cell identifier corresponding to the CSG closed femto base station, the operation mode may be changed to a CSG open femto base station to allow access of a non-member terminal. In this case, the mode switching of one's own may use a different type of broadcast signal.

Therefore, in one embodiment of the present invention, the femto base station changes the type / mode according to the situation, broadcasts it, and does not make unnecessary network connection to the terminals based on the broadcasted information, or enables the network connection to the terminals. It is proposed to inform the femto base stations. For convenience of explanation, hereinafter, the femto base station will be described based on changing the 'type' according to the situation.However, unless otherwise indicated, the femto base station also changes the 'mode' while maintaining the 'type'. Assume that it is included.

Hereinafter, a method of using the type change of the CSG femto base station according to the situation (for example, the resource situation) of the femto base station will be described as described above.

First embodiment

FIG. 2 illustrates a method of converting a type to a CSG closed femto base station by the CSG open femto base station according to an embodiment of the present invention, and notifying the terminal of unnecessary network entry (NE) or handover (HO). Figure is shown.

In FIG. 2, it is assumed that the first terminal AMS 1 is a CSG member terminal and the second terminal AMS 2 is a non-member terminal. In addition, it is assumed that the first terminal is receiving a service from the CSG open femto base station.

If the resources of the CSG open femto base station are exhausted, the femto base station according to the present embodiment may switch to the CSG closed femto base station and inform the first and second terminals thereof. The type conversion of the femto base station may be according to the state of the femto base station (for example, resource conditions) or may be according to the command of the macro base station.

Although FIG. 2 illustrates broadcasting of the type conversion information of the femto base station through the SFH, it may be performed through an AAI-SCD message or another message. This may also be seen that the macro base station plays a role similar to a cell bar indicator for prohibiting access of the terminal.

The second terminal receiving the type conversion information of the femto base station as described above may not unnecessarily attempt to enter the network or handover to the femto base station.

3 is a diagram illustrating a method in which a CSG closed femto base station converts a type to a CSG open femto base station according to an embodiment of the present invention, and notifies the terminal of a network entry (NE) or a handover (HO) of the terminal. One drawing.

In FIG. 3, as in FIG. 2, it is assumed that the first terminal AMS 1 is a CSG member terminal and the second terminal AMS 2 is a non-member terminal. In addition, it is assumed that the first terminal is receiving a service from the CSG open femto base station.

The CSG closed femto base station according to the present embodiment may change the femto type when sufficient resources are available or when the user wants to service more terminals through his or her femto base station by changing the femto type. FIG. 3 illustrates an example in which a type of a CSG closed femto base station is changed to a CSG opening and broadcasted through an SFH to give a non-member second terminal AMS 2 an opportunity to enter a network. The changed cell type may be transmitted through another broadcast message or MAC message in addition to SFH.

When the CSG open femto base station is no longer able to accommodate additional non-member terminals, the femto type is broadcasted to the SFH from CSG open to CSG closed, and the cell bar indication is used as described above. You can expect the same effect.

Second embodiment

Meanwhile, a method of using a cell bar bit independently of the type change of the CSG femto base station as described above will be described.

FIG. 4 is a diagram for describing a method of a base station prohibiting network entry / handover of non-member terminals without a cell type change using a CSG cell bar according to a resource state of a CSG open femto base station according to another embodiment of the present invention. .

The CSG open femto base station may broadcast the CSG cell bar bit 'on' (for example, set to 1) through the SFH when the non-CSG member terminals are not available to service. In addition, in the present embodiment, a Tcsg_barred timer is also broadcasted to indicate a period in which a non-member CSG terminal is prohibited from accessing by using a timer, and the non-CSG members are connected to the non-CSG members until the timer expires (for example, handover). Or initial network entry request) may be denied. However, in the present embodiment, even if the CSG cell bar bit is 'ON', the CSG member terminals may be allowed to access.

FIG. 5 is a diagram for describing a method in which a femto base station uses the same cell bit as the cell bit used by the macro base station according to another embodiment of the present invention.

The cell bit according to the present embodiment is assumed to perform a function of inhibiting connection of not only non-member terminals but also CSG member terminals. That is, the femto base station may broadcast by broadcasting the femto cell bar bit 'ON' (for example, set to 1) through SFH for cell load balance.

Neighboring UEs should avoid access to the femto base station, which assumes that this state is maintained during the Tfemto barred timer transmitted with the femto cell bit. In other words, the femto cell bar bit according to the present embodiment has a meaning irrespective of the femto subscriber type.

Third Embodiment

Meanwhile, in the above-described embodiments, the selba bit or the corresponding information is transmitted through the superframe header, but in this case, the superframe header configuration of the macro base station and the femto base station is different due to the addition of the selba bit. Hereinafter, a method for notifying a CSG cell bar bit or corresponding information to a terminal without changing a superframe header configuration broadcasted by a femto base station is proposed.

In this case, a predetermined MAC message may be used as a method of transmitting the CSG cell bar bit, and a ranging response (AAI_RNG-RSP) message may be used as an example. This will be described with reference to FIG. 6.

FIG. 6 is a diagram illustrating a method in which a CSG closed femto base station restricts access of a non-member terminal using a CSG cell bar bit through a ranging response message according to another embodiment of the present invention.

Referring to FIG. 6, the non-member terminal receives the preamble and SFH of the CSG closed femto base station (S601). Through this, the UE can know the type of the femto base station, and since the cell bar of the SFH is set to 0, it will attempt to access the femto base station.

Accordingly, the terminal transmits the ranging code to the femto base station (S602), and receives a ranging acknowledgment (AAI_RNG-ACK) message indicating the ranging status information from the femto base station (S603).

At this time, if the ranging state is a success (success), the terminal transmits a ranging request (AAI_RNG-REQ) message to the femto base station (S604).

In this case, the femto base station always sets the CSG cell bar of the ranging response (AAI_RNG-RSP) message to '1' and transmits it to the terminal (S605).

As the terminal receives the ranging response message with the CSG cell bit set to 1, the terminal does not attempt to enter the corresponding femto base station since the terminal is a non-member terminal.

Next, a case of the CSG open femto base station will be described with reference to FIG. 7.

FIG. 7 is a diagram for describing a method in which a CSG open femto base station restricts access of a non-member terminal using a CSG cell bar bit through a ranging response message according to another embodiment of the present invention.

In FIG. 7, except that the femto base station is a CSG open type, steps S701 to S704 are similar to steps S601 to S604 in FIG. 6, and thus descriptions thereof will be omitted for simplicity.

In step S705, if the CSG open femto base station does not want to allow the entry of the non-member terminal for load balancing or other reasons, the CSG open femto base station transmits a ranging response message with the CSG cell bar set to 1. On the contrary, when the femto base station allows entry of non-member terminals, the femto base station may set the CSG cell bar of the ranging response message to zero.

Accordingly, the terminal may determine whether to stop the entry attempt according to the value of the CSG cell bar.

The reason why the ranging response message is used in the embodiments described above with reference to FIGS. 6 and 7 is that it may not be determined whether the UE is a CSG member during the ranging process. Accordingly, by including the CSG cell bar bit in the ranging response message, the terminal may determine whether to stop the network entry procedure when it is possible to determine whether the terminal is a CSG member of the base station currently attempting to enter the network.

Fourth embodiment

Hereinafter, a technique for indicating whether a terminal is a member according to another embodiment of the present invention will be described.

FIG. 8 is a diagram for describing a method of transmitting an indicator indicating whether a terminal is a member of a corresponding femto base station according to another embodiment of the present invention, and determining whether to allow an access based on the femto base station.

Referring to FIG. 8, there may be a time when a CSG open femto base station can no longer provide services to non-CSG member terminals due to resource exhaustion (S801). Non-CSG member terminals that are not aware of this situation may continue to attempt network entry.

At this time, the non-member terminal (AMS 1) receives the preamble and SFH from the femto base station to obtain system information (S802) and transmits the ranging code to the femto base station (S803).

In response, the femto base station transmits a ranging acknowledgment (AAI_RNG-ACK) message indicating the ranging state to the terminal (S804), and if the ranging state indicated by the AAI_RNG-ACK message is success, the terminal is a femto base station The ranging request message is transmitted (S805).

In this case, the terminal (non-CSG member) may transmit the 'OFF' CSG member bit to indicate that the terminal is not a CSG member when transmitting the AAI_RNG-REQ.

The CSG open femto base station that has received this may transmit preamble index information in order to redirect to a neighboring base station together with a ranging abort timer in the AAI_RNG_RSP message (S806).

9 is a diagram for describing a method of informing a terminal whether a terminal is a member according to another embodiment of the present invention.

FIG. 9 is similar to the technique of FIG. 8, but different in that it transmits the CSG member bits in a Quick Access Message. Therefore, description of overlapping portions will be omitted.

Specifically, when performing network entry to the CSG open base station, the non-CSG member terminal may transmit a message together with a ranging code (S903). When the CSG member bit is 'OFF' and transmitted in the message part, the femto base station may recognize that the non-member terminal is entering the network. Therefore, when the femto base station cannot enter the non-member network at this time, the femto base station may reject the access of the terminal through the ranging response message (S906).

Fifth Embodiment

Hereinafter, as another aspect of the present invention, a method of broadcasting a network entry condition of a CSG femto base station will be described.

If the connection is allowed when the current connection is poor or no other base station can be found even though the terminal discovers the CSG open femto base station in the vicinity, the CSG open femto base station broadcasts such a trigger condition in advance, thereby unnecessary connection of the terminal. You need to stop trying. If the trigger condition is not broadcasted in advance, non-CSG members may attempt handover or network reentry whenever a CSG open femto base station is found.

Therefore, the present embodiment proposes to broadcast the network re-entry conditions of the CSG open femto base station through the SFH. In addition, macro base stations and neighboring femto base stations propose to broadcast a trigger condition for handover to a CSG open femto base station.

Table 1 shows a method of broadcasting the network entry conditions of the CSG open femto base station through the SFH. In this embodiment, it is assumed that the macro base station or the neighbor femto base stations broadcast a trigger condition for handover to the CSG open femto base station.

name Length
(beat) value Type 2 (MSB) Trigger Metric Type:
0x0: CINR Metric
0x1: RSSI metric
0x2: Number of lost frames metric Function 2 Calculation of trigger conditions:
0x0: the metric of all neighboring base stations is greater than the absolute value
0x1: Metrics of all neighboring base stations are less than absolute
0x2: The metric of all neighboring base stations is smaller in relative value than the serving base station metric.
0x3: Metric of serving base station is greater than absolute Duration 3 (LSB) 2 ^ p (p: number of frames)

In Table 1, Type is a field indicating a criterion indicating a link state of a neighbor / serving base station and may include a CINR, an RSSI, and a number of missed frames. In particular, the number of lost frames may be used for estimating that the terminal does not find the base station when the number of lost frames is measured above a predetermined value.

The Duration field indicates that link state measurements are made for 2 ^ p frames to increase the reliability of the results.

The application method of Table 1 will be described with specific examples.

Example 1: (Type / Function / Duration = 0x2 / 0x3 / 2 ^ p)

It indicates when the number of lost frames from all neighboring base stations is larger than the absolute value during the 2 ^ P frame period (that is, when there are no base stations with link states that can be connected to the surroundings).

Example 2: (Type / Function / Duration = 0x0 / 0x1 / 2 ^ p)

The link status of all neighboring base stations is measured to indicate when the CINR is smaller than the absolute value (that is, when there is no base station with a CINR value close enough to maintain the connection in the vicinity).

Meanwhile, Table 2 shows a handover trigger condition transmitted by the existing macro base station.

The trigger condition for entering the CSG open femto base station according to an embodiment of the present invention proposes to add a function as shown in Table 3 to the handover trigger condition transmitted from the macro base station as shown in Table 2 above. do.

name Length
(beat) value Type 2 (MSB) Trigger Metric Type:
0x0: CINR Metric
0x1: RSSI metric
0x2: Number of lost frames metric Function 2 Calculation of trigger conditions:
0x0: the metrics of all other neighboring base stations are greater than the absolute value
0x7: Metrics of all other neighboring base stations are less than absolute Duration 3 (LSB) -

In Table 3, functions 0x0 and 0x7 use the values reserved in Table 2, and assume that they are limited to conditions for handover to the CSG open femto base station according to the present embodiment. It is also assumed that the CSG open femto base station is included in a neighbor list transmitted by the macro base station.

The trigger condition which added Table 3 to said Table 2 is demonstrated using a specific example.

Example 1: (Type / Function / Operation = 0x2 / 0x0 / Handover)

Indicates when the number of frames lost from all other neighbor base stations except the CSG open femto base station is greater than the absolute value (ie, when no other neighbor base stations can be found other than the CSG open femto base station).

Example 2: (Type / Function / Operation = 0x0 / 0x7 / Handover)

It indicates when the measured CINR values of all other neighbor base stations except the CSG open femto base station are smaller than the absolute value.

Each of the above-described embodiments and the embodiments according to the embodiments may be used in combination with each other according to circumstances.

Terminal and base station device configuration

Hereinafter, an apparatus configuration for performing a communication method of a terminal, a femto base station, and a macro base station as described above will be described.

10 is a diagram for briefly describing an apparatus configuration of a terminal, a femto base station, and a macro base station according to embodiments of the present invention.

The apparatus 50 shown in FIG. 10 may be a terminal, a femto base station, or a macro base station described in the above embodiments. When the device 50 is a femto base station device, the processor 51 of the device 50 controls the conversion of the CSG open / closed type according to the situation, and the cell type change information is transmitted through the RF module 53. Can transmit

The device 50 includes a processor 51, a memory 52, a radio frequency unit (RF unit) 53, a display unit 54, and a user interface unit 55. Layers of the air interface protocol are implemented in the processor 51. The processor 51 provides a control plan and a user plan. The function of each layer may be implemented in the processor 51. The processor 51 may include a contention resolution timer. Memory 52 is coupled to processor 51 to store operating systems, applications, and general files. If the device 50 is a terminal, the display unit 54 may display a variety of information and use well-known elements such as a liquid crystal display (LCD) and an organic light emitting diode (OLED). The user interface unit 55 may be composed of a combination of well known user interfaces such as a keypad, a touch screen, and the like. The RF unit 53 may be connected to the processor 51 to transmit and receive a radio signal. The RF unit 53 may be divided into a transmission module and a reception module.

The layers of the air interface protocol between the terminal and the network are based on the lower three layers of the open system interconnection (OSI) model, which is well known in a communication system, for the first layer L1, the second layer L2, and the third layer. Can be classified as (L3). The physical layer or the PHY layer belongs to the first layer and provides an information transmission service through a physical channel. A radio resource control (RRC) layer belongs to the third layer and provides control radio resources between the UE and the network. The terminal and the network exchange RRC messages through the RRC layer.

Embodiments according to the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the hardware implementation, the control information transmission and reception method according to an embodiment of the present invention is one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable (PLDs) logic devices), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of the implementation by firmware or software, according to an embodiment of the present invention, may be implemented in the form of a module, procedure, function, etc. to perform the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

It is obvious that the claims may be combined to form an embodiment by combining claims that do not have an explicit citation relationship in the claims or as new claims by post-application correction.

Claims (15)

In a mobile communication system comprising a macro base station, at least one femto base station and at least one terminal, a method of performing communication by a particular femto base station,
Broadcasting cell type information indicating that the specific femto base station is the CSG femto base station among an Open Subscriber Group (OSG) femto base station and a Closed Subscriber Group (CSG) femto base station;
Receiving a first message for attempting to enter a network from a specific terminal; And
And transmitting a second message to the specific terminal, the second message including access permission information indicating whether the non-member terminal is allowed to access the specific femto base station. The method of claim 1,
When the specific femto base station is a CSG closed femto base station (CSG Closed Femto ABS),
The access permission information is a communication method of the femto base station, characterized in that it is always set to a value that does not allow the connection of the non-member terminal. The method of claim 1,
When the specific femto base station is a CSG open femto base station (CSG Open Femto ABS),
The access permission information of the femto base station, characterized in that the value is determined according to a specific condition. The method of claim 3,
The specific condition includes a resource level available to the specific femto base station or the interference coordination situation of the non-member terminal interfered by the specific femto base station. The method of claim 1,
The first message is a ranging request (AAI_RNG-REQ) message.
The second message is a ranging response (AAI_RNG-RSP) message, characterized in that the communication method of the femto base station. In the mobile communication system comprising a macro base station, at least one femto base station and at least one terminal, a method for performing communication by a specific terminal,
Receiving cell type information indicating that the CSG femto base station is selected from an Open Subscriber Group (OSG) femto base station and a Closed Subscriber Group (CSG) femto base station broadcast from a specific femto base station;
Transmitting a first message for attempting to enter a network to the specific femto base station;
Receiving a second message from the specific femto base station including access permission information indicating whether the non-member terminal is allowed to access the specific femto base station; And
And determining whether to connect to the specific femto base station according to the value of the access permission information and whether the specific terminal is a member of the specific femto base station. The method of claim 6,
When the specific femto base station is a CSG closed femto base station (CSG Closed Femto ABS),
The access permission information is always set to a value that does not allow access of non-member terminals,
The determining step,
And determining to access the specific femto base station only when the specific terminal is a member of the specific femto base station. The method of claim 6,
When the specific femto base station is a CSG open femto base station (CSG Open Femto ABS),
The access permission information of the terminal characterized in that the value is determined according to a specific condition. The method of claim 8,
The specific condition includes a resource level available to the specific femto base station or an interference coordination situation of a non-member terminal interfered by the specific femto base station. The method of claim 6,
The first message is a ranging request (AAI_RNG-REQ) message.
And the second message is a ranging response (AAI_RNG-RSP) message. In a specific terminal device for performing communication in a mobile communication system including a macro base station, at least one femto base station and at least one terminal,
A processor; And
Including a radio communication (RF) module for transmitting and receiving a radio signal with the outside under the control of the processor,
The processor comprising:
A first message for acquiring cell type information, which is broadcast from a specific femto base station and indicates that the CSG femto base station is among the Open Subscriber Group (OSG) femto base station and the Closed Subscriber Group (CSG) femto base station, and attempts to enter a network to the specific femto base station. Transmits and obtains access permission information indicating whether to allow access of a non-member terminal to the specific femto base station through a second message received from the specific femto base station, and thus the value of the access permission information and the specific terminal device; And determine whether to connect to the specific femto base station according to whether or not is a member of the specific femto base station. 12. The method of claim 11,
When the specific femto base station is a CSG closed femto base station (CSG Closed Femto ABS),
The access permission information is always set to a value that does not allow access of non-member terminals,
The processor comprising:
And controlling the access to the specific femto base station only when the specific terminal device is a member of the specific femto base station. 12. The method of claim 11,
When the specific femto base station is a CSG open femto base station (CSG Open Femto ABS),
And the access permission information is determined according to a specific condition. The method of claim 13,
The specific condition includes a resource level available to the specific femto base station or an interference coordination situation of a non-member terminal interfered by the specific femto base station. 12. The method of claim 11,
The first message is a ranging request (AAI_RNG-REQ) message.
And the second message is a ranging response (AAI_RNG-RSP) message.

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