JP4990357B2 - Information providing apparatus and method for intermediate link area in broadband wireless access communication system using multi-hop relay system - Google Patents

Description

  The present invention relates to a broadband wireless access communication system using a multi-hop relay scheme, and more particularly, to an apparatus and method for providing information about an intermediate link (zone) on which information transmitted to a terminal is relayed.

  In a 4th generation (4G) communication system, which is a next generation communication system, a user has a service with various service qualities (Quality of Service: QoS) having a transmission rate of about 100 Mbps. There is a lot of research going on. In particular, in the current 4G communication system, broadband wireless access (such as a wireless area network (hereinafter referred to as a LAN) system) and a wireless metropolitan area network (hereinafter referred to as a MAN) system are used. Broadband wireless access (BWA) communication systems are being actively studied to support high-speed services in a form that guarantees mobility and QoS. The typical communication systems are the Institute of Electrical and Electronics Engineers (IEEE) 802.16d communication system and the IEEE 802.16e communication system.

  In the IEEE 802.16d communication system and the IEEE 802.16e communication system, an orthogonal frequency division multiplexing (hereinafter referred to as OFDM) system / orthogonal frequency division multiple connection (physical channel) is used. An Orthogonal Frequency Division Multiple Access (hereinafter referred to as OFDMA) method is used. The IEEE 802.16d communication system is currently in a state in which a subscriber station (SS: Subscriber Station; hereinafter referred to as SS) is fixed, that is, a state in which SS mobility is not considered at all and a single cell structure. It is a system that is considered. In contrast, the IEEE 802.16e communication system is a system that considers the mobility of the SS in the IEEE 802.16d communication system, and the SS having the mobility is a terminal (Mobile Station; hereinafter referred to as MS). Called.

  FIG. 1 is a diagram schematically illustrating a structure of a general IEEE 802.16e communication system.

  As shown in FIG. 1, the IEEE 802.16e communication system has a multi-cell structure, that is, a base station (BS) 110 having a cell 100 and a cell 150 and managing the cell 100. And a base station 140 that manages the cell 150, and a plurality of MSs 111, 113, 130, 151, and 153. Signal transmission / reception between the base stations 110 and 140 and the MSs 111, 113, 130, 151, and 153 is performed using the OFDM / OFDMA scheme. Here, among the MSs 111, 113, 130, 151, and 153, the MS 130 is located in a border area between the cell 100 and the cell 150, that is, a handover area. Accordingly, when the MS 130 moves to the cell 150 side managed by the base station 140 while transmitting and receiving signals to and from the base station 110, the serving base station (serving BS) moves from the base station 110 to the base station 140. Be changed.

  In a general IEEE 802.16e communication system, signaling is transmitted and received between the fixed base station and the MS as shown in FIG. 1 through a direct link. Therefore, reliability between the base station and the MS is improved. A high wireless communication link can be easily configured. However, since the position of the base station is fixed in the IEEE 802.16e communication system, the configuration of the wireless network is low in flexibility. Therefore, in a wireless environment in which the traffic distribution and the call request amount change drastically, the efficiency is low. It is difficult to provide a typical communication service.

  In order to overcome these disadvantages, a data transmission scheme of a multi-hop relay mode is used as the IEEE 802.16e by using a fixed relay station (RS), a mobile relay station, or a general MS. The present invention can be applied to a general cellular radio access communication system such as a communication system. The wireless access communication system using the multi-hop relay method can quickly reconfigure the network in response to a change in the communication environment, and can operate the entire wireless network more efficiently. For example, a wireless communication system using the multi-hop relay scheme can expand the cell service area and increase the system capacity. That is, when the channel state between the base station and the MS is poor, by installing a relay station between the base station and the MS, and configuring a multi-hop relay path through the relay station, A radio channel with better channel conditions can be provided to the MS. In addition, by using the multi-hop relay method in a cell boundary region where the channel state is poor from the base station, a higher-speed data channel can be provided and the cell service area can be expanded.

  Here, a structure of a wireless communication system using a multi-hop relay scheme for expanding the base station service area will be described.

  FIG. 2 is a diagram schematically illustrating a structure of a broadband wireless communication system using a multi-hop relay scheme for expanding a base station service area.

  As shown in FIG. 2, the multi-hop relay radio communication system has a multi-cell structure, that is, a cell 200 and a cell 240, and a base station (Base Station: BS) 210 that manages the cell 200. , A base station 250 that manages the cell 240, a plurality of MSs 211 and 213 located in the cell 200 area, and a plurality of MSs 221 that are managed by the base station 210 but exist in the area 230 outside the cell 200 area 223, a relay station 220 that provides a multi-hop relay path between the base station 210 and the MSs 221 and 223 existing in the area 230, and a plurality of MSs 251, 253, and 255 located in the cell 240 area, A plurality of MSs 261 and 263 managed by the base station 250 but existing in the area 270 outside the cell 240 area; Serial constructed from the relay station 260 Metropolitan which provides multihop relay paths between the BS 250 and the MS261,263 existing in the region 270. Here, transmission / reception of signals between the base stations 210 and 250, the relay stations 220 and 260, and the MSs 211, 213, 221, 223, 251, 253, 255, 261, and 263 uses the OFDM / OFDMA scheme. Done.

  At this time, the MSs 211 and 213 and the relay station 220 included in the cell 200 region can directly transmit and receive signals to and from the base station 210, but the MSs 221 and 223 existing in the region 230 are connected to the base station 210. I cannot send or receive signals directly. Therefore, the relay station 220 manages the area 230 and relays signals between the base station 210 and the MSs 221 and 223 that cannot directly transmit and receive signals, and the MSs 221 and 223 pass through the relay station 220. The base station 210 can transmit and receive signals. Also, the MSs 251, 253, 255 and the relay station 260 included in the cell 240 region can directly transmit and receive signals to and from the base station 250, but the MSs 261, 263 existing in the region 270 are connected to the base station 250. I cannot send or receive signals directly. Therefore, the relay station 260 manages the area 270 and relays signals between the base station 250 and the MSs 261 and 263 that cannot directly transmit and receive signals, and the MSs 261 and 263 pass through the relay station 260. The base station 250 can transmit and receive signals.

  Here, in the broadband wireless communication system using the multi-hop relay of FIG. 2, the relay stations 220 and 260 are infrastructure relay stations that are installed by a service provider and managed by the base stations 210 and 250 in advance. There may be a client relay station operating as a subscriber station (SS or MS) or a relay station depending on the situation. In addition, the relay stations 220 and 260 are non-mobile fixed relay stations, non-residential relay stations having non-resident characteristics (eg, notebook personal computers), or the MS It can be a mobile relay station with mobility.

  On the other hand, when a relay station is used to expand the cell area, the conventional frame structure defined between the base station and the terminal is expanded to define the frame structure between the base station, the relay station, and the terminal. There must be. That is, the frame structure must be defined so that the base station can communicate with a plurality of relay stations and terminals based on a single communication platform. For this purpose, the base station downlink frame must be divided into an area for communication between the base station and the terminal and an area for communication between the base station and the relay station. The area for communication between the terminal and the base station and the area for communication between the relay station and the terminal must be divided. That is, the limited resources must be appropriately divided to accommodate the relay station. However, the number of relay stations connected to the base station and the channel environment are extremely fluid. In other words, the cell environment is extremely fluid. Therefore, an area or relay station for communication between the base station and the relay station is required. -It may be extremely irrational to use a fixed area for communication between base stations. Therefore, recently, techniques for dynamically operating such areas have been proposed. If such a region is dynamically changed in this way, a signaling procedure must be defined that can provide the region information to the relay station.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus and method for informing a relay station of information on an intermediate link area in which a base station and a relay station communicate in a broadband wireless access communication system using a multi-hop relay system. is there.

  Another object of the present invention is to provide an apparatus and method for informing a relay station that performs initial connection to a base station of information about an intermediate link region in a broadband wireless access communication system that uses a multi-hop relay scheme. .

  Still another object of the present invention is to relay size change information in a broadband wireless access communication system using a multi-hop relay scheme when the size of an intermediate link area in which a base station and a relay station communicate is changed. It is to provide an apparatus and method for informing a station.

  Still another object of the present invention is to inform the relay station of information related to the intermediate link area of the target base station when a mobile relay station performs handover in a broadband wireless access communication system using a multi-hop relay scheme. It is providing the apparatus and method of this.

In order to achieve the above object, according to an aspect of the present invention, there is provided a communication method of a base station in a cellular communication system using a multi-hop relay scheme, wherein a process of performing a network participation procedure with the relay station, after network participation procedure ends, the process of generating a message including relay link zone information regarding the relay link area and the base station and the relay station to communicate, said generated message to a physical layer processor, pre SL in Tsugikyoku And the message includes an intermediate area indicator indicating that the intermediate link area information is included.

According to another aspect of the present invention, there is provided a communication method of a base station in a cellular communication system using a multi-hop relay scheme, wherein whether or not an intermediate link area in which the base station and the relay station communicate is changed A process of checking the intermediate link area, a process of generating a message including change information of the intermediate link area, and a process of performing physical layer processing on the generated message and broadcasting to the relay station look including the door, the message, the information indicating a start of a relay link zone in the next frame, characterized in containing Mukoto.

According to still another aspect of the present invention, there is provided a communication method of a base station in a cellular communication system using a multi-hop relay scheme, and when a relay station is handed over, a frame of a frame in which a target base station communicates with the relay station. a process of receiving the relay link zone information defining relay link zone from the target base station, and generating a message including the relay link zone information of the target base station, the message to a physical layer processing, the And a process of transmitting to the relay station to be handed over.

According to still another aspect of the present invention, there is provided a communication method of a relay station in a cellular communication system using a multi-hop relay system, a process of performing a network participation procedure with the base station, and after completion of the network participation procedure. Receiving a message including intermediate link area information related to an intermediate link area in which the base station and the relay station communicate, and performing a relay station operation in an area indicated by the intermediate link area information, And an intermediate area indicator indicating whether the intermediate link area information is included.

According to still another aspect of the present invention, there is provided a communication method of a relay station in a cellular communication system using a multi-hop relay method, wherein a message including change information of an intermediate link region in which a base station and a relay station communicate A process of checking whether the message has been received, a process of confirming a changed intermediate link area from the message when the message is received, and a process of performing a relay station operation in the changed intermediate link area. see the message, information indicating a start of a relay link zone in a next frame, characterized in containing Mukoto.

According to still another aspect of the present invention, there is provided a communication method of a relay station in a cellular communication system using a multi-hop relay scheme, and an intermediate link region of a frame in which a target base station communicates with the relay station when performing handover. a process of receiving a message from the target base station including relay link zone information defining a process to check the relay link zone of the target base station from the message, after completing the handover, the link between during the previous SL And a process of performing relay station operation in the area.

  As described above, the present invention proposes a scheme for providing intermediate link area information for a base station and a relay station to communicate with the relay station in a broadband wireless access communication system using a multi-hop relay scheme. . The present invention has an advantage that the limited resources can be efficiently used because the intermediate link region can be dynamically changed in accordance with the cell environment within the limited frame.

  Hereinafter, the operation principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a specific description of a related known function or configuration may obscure the gist of the present invention, the detailed description thereof will be omitted. . The terms described later are terms defined in consideration of the function of the present invention, and this may vary depending on the intention of the user, the operator, or customs. Therefore, the definition must be made based on the contents throughout this specification.

  The present invention relates to a signaling procedure for providing a relay station with information on an intermediate link area in which information to be relayed to a terminal is transmitted in a broadband wireless access (BWA) communication system using a multi-hop relay scheme. Propose. Hereinafter, the present invention provides a method for notifying the relay station that performs initial connection to the base station of information related to the intermediate link region, and a method for notifying the relay station of the size change information when the size of the intermediate link region changes. Is described. Also, a method for notifying the relay station of information related to the intermediate link area of the target base station when a mobile relay station performs handover will be described.

  Here, the broadband wireless access communication system using the multi-hop relay scheme uses, for example, an Orthogonal Frequency Division Multiplexing (OFDM) scheme or an Orthogonal Frequency Division Multiple Access (OFDMA) scheme. It is a communication system. The broadband wireless access communication system using the multi-hop relay scheme transmits high-speed data by transmitting a physical channel signal using a plurality of sub-carriers in order to use the OFDM / OFDMA scheme. Transmission is possible, and mobility of the terminal can be supported by a multi-cell structure.

  In addition, the relay station of the broadband wireless access communication system using the multi-hop relay scheme may be a fixed node or a mobile node, or may be a specific system installed by a base station. That is, an arbitrary node having the above characteristics can be selected as a relay station according to a relay station capability negotiation procedure with the base station according to a pre-defined standard for extending the cell area of the base station.

  In the following description, a broadband wireless access communication system using multiple carriers will be described as an example. However, the present invention is similarly applied to a cellular-based communication system using a multi-hop relay scheme. Can do.

  FIG. 3 shows a frame structure for providing a synchronization channel synchronized with a terminal or a relay station in a broadband wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention.

  As shown in FIG. 3, the frame structure provides a synchronization channel for the terminal in a preamble form so that the synchronization and cell search of the terminal are easy. In addition, a synchronization channel for the relay station is provided in a postamble form so that the synchronization and cell search of the relay station are easy. In this way, the base station configures the front end and the rear end of the downlink subframe 310 of the base station frame 300 as a synchronization channel, so that the terminal or the relay station can receive synchronization information and a synchronization information from a synchronization channel at a fixed position. Neighboring base station information can be acquired.

  In addition, the unidirectional subframes 310 and 320 of the base station frame 300 are time-multiplexed into the first areas 311 and 321 and the second areas 313 and 323. Here, the first regions 311 and 321 and the second regions 313 and 323 may have a fixed length or may be dynamically changed according to a cell environment.

  In the first areas 311 and 321 of the base station frame 300, the base station communicates with a terminal connected through a direct link, and communicates with the relay station in the second areas 313 and 323. At this time, since the sizes of the first areas 311 and 321 and the second areas 313 and 323 can be dynamically changed according to a cell environment, the base station is synchronized with the terminal and the relay station. In order to provide a synchronized synchronization channel, the synchronization or connection channel is allocated to the front ends of the first regions 311 and 321 and the rear ends of the second regions 313 and 323. Here, in the uplink subframe 320, the connection channel (range slot) can be designated through a control channel, not a fixed position.

  The relay station communicates with terminals connected by a direct link in the first areas 361 and 371 of the relay station frame 350. The relay station allocates a synchronization or connection channel to the front ends of the first regions 361 and 371 in order to provide a synchronized channel to the terminal.

  At this time, the sizes of the first areas 311 and 321 and the second areas 313 and 323 of the base station frame 300 and the first areas 361 and 371 of the relay station frame 350 are dynamically changed according to the cell environment. The base station must provide the area size change information to the relay station. Therefore, a relay system considering the frame structure as shown in FIG. 3 must define a signaling procedure for providing communication area change information to the relay station.

  FIG. 4 shows an operation procedure of a base station for providing intermediate link region information to a relay station in a broadband wireless communication system using a multi-hop relay system according to an embodiment of the present invention.

As shown in FIG. 4, the base station first performs an initial connection procedure (network participation procedure) with the relay station in step 401. Here, the base station performs an initial connection procedure with the relay station in the first areas 311 and 321 of the base station frame 300 in the frame structure of FIG. That is, the downlink message required for the initial connection procedure is transmitted to the relay station via the first downlink region 311, and the uplink message is transmitted to the base station via the first uplink region 321. . When the relay station operation is activated after performing the initial connection procedure, the base station and the relay station supporting the relay service in the intermediate link area corresponding to the second areas 313 and 323 of the base station frame 300 Communicate. At this time, the relay station whose relay station operation is activated performs communication with the terminal in the first areas 361 and 371 of the relay station frame 360.
Therefore, after the initial connection procedure, the base station transmits information of the intermediate link region, that is, the second region 313 of the downlink subframe 310 of the base station frame 300 to the relay station in step 403.

  Therefore, after the initial connection procedure, the base station transmits information of the intermediate link region, that is, the second region 313 of the downlink subframe 310 of the base station frame 300 to the relay station in step 403.

  The intermediate link region information transmitted to the relay station can be transmitted using STC_DL_ZONE_IE that informs information about a region using a specific permutation or a specific transmission diversity mode, and includes the intermediate link region information. The structure of STC_DL_ZONE_IE is as shown in Table 1 below.

  As shown in Table 1, the STC_DL_ZONE_IE includes OFDMA symbol offset information indicating a start point of an area indicated by the IE (Information Element) and replacement information indicating replacement information of the area indicated by the IE. (Permutation) information, and downlink intermediate region indicator (RSDL zone indicator) information that informs that the region indicated by the IE is an intermediate link region.

  On the other hand, the method of notifying the relay station of the intermediate link area information in step 403 includes a method of using one bit of STC_DL_ZONE_IE as a downlink intermediate area indicator (RS DL zone indicator) as shown in Table 1. It is also possible to consider how to utilize other existing messages or define new messages. As an example, a method in which a 1-bit downlink intermediate area indicator (RSDL zone indicator) is included in the AAS_DL_IE used to notify that it is an AAS (Adaptive Antenna System) area may be used. In this case, the structure of the AAS_DL_IE is as shown in Table 2 below.

  In still another method of informing the relay station of the intermediate link area information, a FCH (frame control header) includes a downlink intermediate area indicator (RSDL zone indicator) and a GAP / PAPR (Peak to Average Power Ratio) reduction area. The GAP / PAPR reduction IE used to indicate (reduction region) can be used to notify the intermediate link region. In this case, the FCH may include downlink intermediate region indicator information as shown in Table 3 below.

The relay station that has received the FCH including the downlink intermediate region indicator information recognizes that the region indicated by the GAP / PAPR reduction IE included in the downlink map (MAP) is the intermediate link region. The relay station functions in the area indicated by the GAP / PAPR reduction.
When the GAP / PAPR reduction IE is used, the GAP / PAPR reduction IE can be used not only for the purpose of indicating the intermediate link area but also for the original purpose. When used for the original purpose, the lower node (terminal or relay station) of the base station can ignore the received signal when receiving a signal in the area indicated by the GAP / PAPR reduction IE. . Therefore, when receiving a plurality of GAP / PAPR reduction IEs from the base station or the upper relay station, the relay station must be able to distinguish which GAP / PAPR reduction IE is an IE that informs the intermediate link region. Therefore, consider using the F DL RS DL zone indicator to indicate which GAP / PAPR reduction IE is used to notify the intermediate link region among one or more GAP / PAPR reduction IEs. Can do. In such a case, the FCH may include downlink intermediate region indicator information as shown in Table 4 below.

  In Table 4, the downlink intermediate area indicator (RSDL zone indicator) includes GAP / PAPR reduction information (IE) indicating the intermediate link area in the downlink map, and the downlink map. When one or more pieces of GAP / PAPR reduction information are included in the information, it is informed which position of the one or more pieces of GAP / PAPR reduction information the GAP / PAPR reduction information indicating the intermediate link area is located. .

  For example, when a 2-bit value is used as the downlink intermediate region indicator (RSDL zone indicator) and the value of the downlink intermediate region indicator (RSDL zone indicator) is set to 01, the relay station Among the GAP / PAPR reduction information in the downlink map, the first GAP / PAPR reduction information that appears can be recognized as an IE for notifying the intermediate link area. Accordingly, the relay station that has received the FCH with the downlink intermediate region indicator (RSDL zone indicator) value set to 01 receives the first GAP / PAPR reduction information in the downlink map. This is recognized as an IE that informs the link area, and performs a relay function in the area indicated by the GAP / PAPR reduction information.

  In the above description, it is described that the FDL RS DL zone indicator and GAP / PAPR reduction information used to represent the intermediate link region are used to inform the intermediate link region of the next frame. Can be used as information indicating an intermediate link region applied in the next second frame, in the next third frame, or in subsequent frames. This can be determined by the system initialization value, or can be applied via system information. Also, once set values can be fixed and used, and can be changed during system operation. In the unlikely event that the base station is changed during system operation, the base station must inform the subordinate node of the change contents via the system information (system information) and the like.

  On the other hand, the terminal that has received the GAP / PAPR reduction IE including the intermediate link area information recognizes that the area specified by the GAP / PAPR reduction IE is not used.

  Thereafter, in step 405, the base station determines whether the size of the intermediate link region corresponding to the second region 313 of the downlink subframe 310 of the base station frame 300 needs to be changed in the next frame. To do. If it is not necessary to change the size of the intermediate link area, the base station proceeds to step 407 and maintains the current intermediate link area. If it is necessary to change the size of the intermediate link area, the base station proceeds to step 409 and transmits the change information of the intermediate link area to the relay station.

  The notification message of the change of the intermediate link area for the next frame transmitted to the relay station has a structure as shown in Table 5 below.

  As shown in Table 5, the intermediate link region change notification message (DL_Frame_Prefix message) is included in an FCH (frame control header) transmitted from the intermediate link region to the relay station, and the DL_Frame_Prefix is: Sub channel group (used subchannel bitmap) information used in the intermediate link region of the frame, DL-MAP repetitive coding instruction (repetition_coding_indication) information immediately after the RS_Frame_Prefix, DL-MAP encoding instruction (coding_indication) information, The DL-MAP length information and the next frame Start offset information (OFDMA symbol offset or OFDMA symbol index) of the intermediate link area. Here, in the start offset information field of the intermediate link area, whether or not the start offset is changed and the start offset increase / decrease information can be designated. For example, if the OFDMA symbol offset value is 0b00000, it means that the start offset of the intermediate link area of the next frame is not changed, and if the value is 0b0xxx, the next value is 0b0xxxx. Means that the start offset of the intermediate link area of the next frame is increased by xxxx symbols, and if the value is 0b1xxx, it means that the start offset of the intermediate link area of the next frame is decreased by xxx symbols. To do. The OFDMA symbol offset value can be applied in consideration of the degree of link change, and can follow a predetermined pattern such as exponential increase / decrease or permutation increase / decrease in addition to the sequential increase / decrease method described in Table 5.

  Table 5 is an example, and the change information of the intermediate link area for the next frame may be transmitted to the relay station via a DL-MAP message transmitted from the intermediate link area of the current frame. Table 6 below shows an RS_DL-MAP message including change information of the intermediate link region.

  As shown in Table 6, the RS_DL-MAP message is a compressed indicator information indicating that it is a compression map, and the uplink subframe 320 of the base station frame 300 after the RS_DL-MAP message. Among them, RS UL MAP attached information indicating presence / absence of an RS_UL-MAP message indicating map information in the intermediate link region 323, and the next intermediate link indicating presence / absence of change of start offset of the intermediate link region of the next frame Next, an area change instruction (Next RS DL zone change indicator) information and an OFDMA symbol offset (OFDMA symbol offset) indicating the degree of increase / decrease of the start offset of the intermediate link area of the next frame fset) information, MAP message length information indicating the RS DL-MAP message length, and the number of OFDMA symbols (No. OFDMA) in the intermediate link region 313 among the downlink subframes 310 of the base station frame 300. symbol) information and a plurality of DL-MAP_IEs which are map information of the intermediate link region 313. The OFDMA symbol offset value of Table 6 is also applied in consideration of the degree of link change, and can follow a predetermined pattern such as exponential increase / decrease or permutation increase / decrease in addition to the sequential increase / decrease method.

  On the other hand, in Table 6, when RS UL MAP indicating map information of the intermediate link region 323 is present in the uplink subframe 320 of the base station frame 300, the structure of the RS_UL-MAP is as shown in Table 7 below. It is.

As shown in Table 7, the RS_UL-MAP message is a UCD (Uplink Channel Descriptor) including profile information of a burst transmitted through the intermediate link region 323 in the uplink subframe 320 of the base station frame 300. ) UCD count (UCD count) information indicating the count value of the message and allocation indicating the allocation start time of the intermediate link region 323 among the uplink subframes 320 of the base station frame 300 included in the RS_UL-MAP message Start time information, number of symbols indicating the number of OFDMA symbols in the intermediate link region 323 (No. OFDMA symbols) information, and the intermediate link region Including multiple of UL-MAP_IE 23 is a map information.
As described above, the change information regarding the intermediate link area can be notified to the relay station via the FCH message or the MAP message. As another example, a separate message can be defined and notified as shown in Table 8 below. it can.

  As shown in Table 8, RS_DL_zone_change_IE for notifying the change of the start offset of the intermediate link region for the next frame is OFDMA symbol offset information indicating the degree of increase / decrease of the start offset of the intermediate link region for the next frame. Etc. The OFDMA symbol offset values in Table 8 are also applied in consideration of the degree of link change, and can follow a fixed pattern such as exponential increase / decrease or permutation increase / decrease in addition to the sequential increase / decrease method.

  FIG. 5 shows an operation procedure of the relay station for receiving the intermediate link region information from the base station in the broadband wireless communication system using the multi-hop relay system according to the embodiment of the present invention.

  As shown in FIG. 5, first, in step 501, the relay station performs an initial connection procedure with the base station in the first areas 311 and 321 of the base station frame 300 of FIG. After completing the initial connection procedure, the relay station that activated the relay station operation receives STC_DL_ZONE_IE of Table 1 from the base station in Step 503, and from STC_DL_ZONE_IE of Table 1 to the base station frame 300 of FIG. Among the second areas 313 and 323, the intermediate link area information corresponding to the downlink 313 is recognized. In addition, the relay station may recognize the intermediate link region information by receiving AAS_DL_IE information including downlink intermediate region indicator information (RS DL zone indicator) from the base station. Alternatively, the relay station receives the FCH including the downlink intermediate region indicator information (RSDL zone indicator) and the downlink map including the GAP / PAPR reduction information (IE) and recognizes the intermediate link region information. You can also.

  In step 505, the relay station performs a relay station operation in the area indicated by the intermediate link area information. That is, a downlink signal from the base station is received in the intermediate link region. Thereafter, the relay station checks in step 507 whether a message notifying the change of the intermediate link area is received from the base station. As described above, the message notifying the change of the intermediate link region may be a DL_Frame_Prefix message (Table 5), the RS_DL-MAP message (Table 6), or the RS_DL_zone_change_IE message (Table 8).

  If a message notifying the change of the intermediate link area is received, the RS proceeds to step 509 to acquire the changed intermediate link area information from the received message, and the acquired information is obtained in the next frame. The relay station operates in the intermediate link area changed according to the received information. If the message notifying the change of the intermediate link area is not received, the relay station proceeds to step 511 and performs the relay station operation while maintaining the current intermediate link area.

  FIG. 4 and FIG. 5 described above describe the relay station that performed the initial connection procedure and the procedure for providing the intermediate link area information to the relay station that performs the relay station operation after performing the initial connection procedure.

  If the relay station has mobility, the relay station must continue to operate for lower nodes managed by the relay station even when the relay station hands over from the serving base station to the target base station. Therefore, the relay station needs to recognize in advance the intermediate link area information in the target base station for communication with the target base station after performing the handover.

  FIG. 6 shows a signaling exchange procedure for providing intermediate link area information of a target base station to a relay station to be handed over in a broadband wireless communication system using a multi-hop relay system according to an embodiment of the present invention. .

  As shown in FIG. 6, first, the target base station 650 provides the intermediate link region information of the target base station 650 itself to the serving base station 610 via the backbone network in step 611. Here, the intermediate link area information of the target base station 650 included in the message exchanged via the backbone network between the serving base station 610 and the target base station 650 is as shown in Table 9 below.

  As shown in Table 9, the intermediate link region information of the target base station includes DL zone symbol offset information indicating a symbol start point of the intermediate link region in the downlink of the target base station. DL zone permutation information indicating downlink replacement information in the intermediate link region of the target base station.

  Then, the serving base station 610 transmits intermediate link area information of the target base station 650 as shown in Table 9 to the relay station 640 in step 613. The intermediate link area information of the target base station may be included in a MOB_NBR-ADV message that the serving base station 610 transmits to the relay station 640 to provide information on neighboring base stations. Alternatively, the intermediate link region information of the target base station is a handover response message transmitted from the base station to the relay station as a response to a handover request message transmitted from the base station to request handover of the relay station or a handover request message from the relay station. Can be included in the message.

  After receiving the intermediate link area information of the target base station 650, the relay station 640 informs the serving base station 610 that the handover to the target base station 650 is performed in step 615, and performs handover to the target base station 650. Do. Then, the serving base station 610 reports the handover of the relay station 640 to the target base station 650 in step 617. At this time, the message reporting the handover of the relay station 640 includes intermediate link area information at the target base station 650 known by the relay station 640.

  Therefore, the target base station 650 does not change the intermediate link area until the handover procedure of the relay station 640 is completed in step 619. Meanwhile, the relay station 640 performs a handover procedure with the target base station 650 in step 621 and uses the intermediate link region information of the target base station 650 acquired from the serving base station 610 in step 623. And continue to function as a relay station in the service area of the target base station 650.

  In the embodiment of the present invention described above, a scheme for notifying the relay station of the information on the downlink 313 among the intermediate link regions corresponding to the second regions 313 and 323 of the base station frame 300 in the frame structure of FIG. It explained to the center. Of the intermediate link area, information on the uplink 323 is relayed via an RS_UL-MAP message without an additional indicator such as an RSDL zone indicator included in STC_DL_ZONE_IE or AAS_DL_IE of Table 1. Can be provided to the station. That is, the RS refers to the RS_UL-MAP message allocation start time information and the number of OFDMA symbols (No. OFDMA symbols) information in Table 7, and includes the uplink in the intermediate link area of each frame. 323 information can be obtained.

  So far, in the broadband wireless access communication system using the multi-hop relay system, the general operation procedure between the base station and the relay station that transmits and receives the intermediate link area information of the frame has been described. Hereinafter, an internal block configuration of a base station (BS) and a relay station (RS) for exchanging the intermediate link area information of the frame will be described. Since a base station and a relay station having the same interface module (communication module) have the same block configuration, in the following description, operations of the base station and the relay station will be described using the apparatus shown in FIG. In the following description, a TDD-OFDMA system is assumed. However, the present invention can be easily applied to FDD-OFDMA systems, hybrid systems that use both TDD and FDD, and cellular-based systems that use other resource partitioning schemes.

  FIG. 7 shows a block configuration of a base station (or relay station) according to the embodiment of the present invention.

  As shown in FIG. 7, the base station (or relay station) according to the present invention includes an RF processor 701, an ADC 703, an OFDM demodulator 705, a decoder 707, a message processor 709, a controller 711, a message generator 713, An encoder 715, an OFDM modulator 717, a DAC 719, an RF processor 721, a switch 723, and a time controller 725 are configured.

  As shown in FIG. 7, the time controller 725 first controls the switching operation of the switch 723 based on time synchronization. For example, if it is a section for receiving a signal, the time controller 725 controls the switch 723 so that the antenna and the RF processor 701 at the receiving end are connected, and if it is a section for transmitting a signal, The switch 723 is controlled so that the antenna and the RF processor 721 at the transmission end are connected.

  During the reception period, the RF processor 701 converts an RF (Radio Frequency) signal received via an antenna into a baseband analog signal. The ADC 703 converts the analog signal from the RF processor 701 into sample data and outputs it. The OFDM demodulator 705 performs FFT (Fast Fourier Transform) on the sample data output from the ADC 703, converts the sample data into frequency domain data, and selects the subcarrier data to be actually received from the frequency domain data. Output.

  The decoder 707 demodulates and decodes the data from the OFDM demodulator 705 according to a predetermined modulation level (MCS level) and outputs the result.

  The message processing unit 709 decomposes the control message input from the decoder 707 and provides the result to the control unit 711. The control unit 711 performs a corresponding process on the information from the message processing unit 709, generates information to be transmitted, and provides it to the message generation unit 713. The message generator 713 generates a message using various information provided from the controller 711 and outputs the message to the physical layer encoder 715.

  The encoder 715 encodes and modulates data from the message generator 713 according to a predetermined modulation level (MCS level) and outputs the result. The OFDM modulator 717 performs IFFT (Inverse Fast Fourier Transform) on the data from the encoder 715 and outputs sample data (OFDM symbols). The DAC 719 converts the sample data into an analog signal and outputs the analog signal. The RF processor 721 converts the analog signal from the DAC 719 into an RF (Radio Frequency) signal and transmits it through the antenna.

In the configuration described above, the control unit 711 is a protocol control unit, and controls the message processing unit 709 and the message generation unit 713. That is, the control unit 711 can perform the functions of the message processing unit 709 and the message generation unit 713. The reason why this is separately configured in the present invention is to distinguish and explain each function. Accordingly, when actually implemented, all of these can be configured to be processed by the control unit 711, and only some of these can be configured to be processed by the control unit 711.
In addition, the control unit 711 provides information necessary for performing protocol processing to a corresponding configuration unit in the physical layer, or generates a control signal in the corresponding configuration unit in the physical layer.

  Hereinafter, operations of the relay station and the base station according to the present invention will be described based on the configuration of FIG. Hereinafter, control message processing performed in a MAC (Media Access Control) layer will be mainly described.

  First, the operation of the base station will be described. The controller 711 controls general processing according to the change of the intermediate link area according to the present invention. When completing the initial connection procedure of an arbitrary relay station, the control unit 711 generates information on an intermediate link area for communicating with the relay station in the downlink subframe of the base station, and sends it to the message generation unit 713. provide. Then, the message generator 713 generates a message including information on the intermediate link area from the controller 711 and transmits the message to the physical layer. Here, a zone switch message (Table 1), an AAS_DL_IE message (Table 2), a GAP / PAPR reduction message, or the like can be used as the message including information on the intermediate link area. When using the GAP / PAPR reduction message, the FCH message may include indicator (RS DL Zone Indication) information indicating that the GAP / PAPR reduction message is a message including intermediate link region information.

  Further, the control unit 711 determines whether or not it is necessary to change the size of the intermediate link region, and if it is determined that the size of the intermediate link region needs to be changed, the intermediate link region Change information is generated and provided to the message generator 713. Then, the message generator 713 generates a message including the intermediate link area change information from the controller 711 and transmits the message to the physical layer. Here, the message including the intermediate link region change information includes a frame control header message (Table 5) transmitted from the current frame to the relay station by the base station, and a relay station downlink map indicating the downlink intermediate region map information. It may be an (RS_DL-MAP) message (Table 6) or a separately defined message (Table 8).

  In addition, when a message including intermediate link region information (Table 6) of a target base station to be handed over by the mobile relay station is received via a backbone network, the control unit 711 determines that the target base station from the received message. Are extracted and provided to the message generator 713. Then, the message generation unit 713 generates a message including the intermediate link region information of the target base station from the control unit 711 and transmits the message to the physical layer. Here, the message including the intermediate link region information of the target base station is an adjacent base station advertisement message (MOB_NBR-ADV message) for providing the adjacent base station information to the relay station, and the base station performs the handover of the relay station. It may be a handover request message transmitted for requesting or a handover response message for responding to a handover request of a mobile relay station.

  In addition, the control unit 711 generates information about an intermediate link region for communicating with the relay station in the uplink subframe and provides the information to the message generation unit 713. Then, the message generator 713 generates a message including the uplink intermediate link region information from the controller 711 and transmits the message to the physical layer. Here, the message including the uplink intermediate link area information may be a relay station uplink map message (Table 4) instructing map information of the uplink intermediate link area.

  The message generated from the message generator 713 is processed into a form that can be transmitted in the physical layer, and then transmitted via an antenna.

  Next, the operation of the relay station will be described. The message processing unit 709 decomposes the control message received from the terminal or the base station and provides the result to the control unit 711. A message including downlink intermediate link region information (STC_DL_Zone_IE, AAS_DL_IE, or GAP / PAPR reduction IE) or a message including downlink intermediate link region change information (DL_Frame_prefix, RSDLMAP, or RS_DL_zone_change base received from RS base) In this case, the message processing unit 709 extracts various control information included in the received message and provides it to the control unit 711.

  Then, the control unit 711 recognizes an intermediate link region for communicating with the base station based on the control information from the message processing unit 711, and synchronizes with the recognized intermediate link region, Take general control to perform the function.

  Further, when a message including intermediate link area information (Table 9) of the target base station is received from the serving base station at the time of handover, the message processing unit 709 uses the intermediate link area of the target base station from the received message. Information is extracted and provided to the controller 711. Then, the control unit 711 recognizes an intermediate link region for communicating with the target base station based on the control information from the message processing unit 711, and is synchronized with the intermediate link region of the target base station after the handover is completed. General control to function as a relay station.

  As described above, the present invention proposes a scheme for providing intermediate link area information for a base station and a relay station to communicate with the relay station in a broadband wireless access communication system using a multi-hop relay scheme. . The present invention has an advantage that the limited resources can be efficiently used because the intermediate link region can be dynamically changed in accordance with the cell environment within the limited frame.

  In the detailed description of the present invention, specific embodiments have been described. Of course, various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the embodiments described, but must be determined not only by the claims described below, but also by the equivalents of the claims.

1 is a diagram schematically illustrating a structure of a general IEEE 802.16e communication system. FIG. 1 is a diagram schematically illustrating a structure of a broadband wireless communication system using a multi-hop relay scheme for expanding a base station service area. FIG. 1 is a diagram illustrating a frame structure for providing a synchronization channel synchronized with a terminal or a relay station in a broadband wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention. FIG. FIG. 5 is a diagram illustrating an operation procedure of a base station for providing intermediate link region information to a relay station in a broadband wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention. FIG. 5 is a diagram illustrating an operation procedure of a relay station for receiving intermediate link region information from a base station in a broadband wireless communication system using a multi-hop relay system according to an embodiment of the present invention. FIG. 6 is a diagram illustrating a signaling exchange procedure for providing intermediate link region information of a target base station to a relay station to be handed over in a broadband wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention. It is a figure which shows the block configuration of the base station (or relay station) by embodiment of this invention.

Claims (38)

A communication method of a base station in a wireless communication system, comprising:
Performing a network participation procedure with the relay station;
A step of generating a message including intermediate link area information regarding an intermediate link area in which the base station and the relay station communicate after the network participation procedure;
And a process of transmitting the generated message to a physical layer processor, before Symbol RELAY station,
The method according to claim 1, wherein the message includes an intermediate area indicator indicating that the intermediate link area information is included. A communication method of a base station in a wireless communication system, comprising:
Performing a network participation procedure with the relay station;
A step of generating a message including intermediate link area information regarding an intermediate link area in which the base station and the relay station communicate after the network participation procedure;
And a process of transmitting the generated message to a physical layer processor, before Symbol RELAY station,
The method includes a middle region indicator indicating whether one of a GAP and a PAPR (Peak to Average Power Ratio) reduction region has been allocated.   When the message includes the intermediate link region information, a frame control header (FCH) message includes indicator information indicating that the message is a message including the intermediate link region information. The method according to claim 2. A communication method of a base station in a wireless communication system, comprising:
Inspecting whether an intermediate link area for communication between the base station and the relay station is changed,
When the intermediate link area is changed, generating a message including change information of the intermediate link area;
Performing a physical layer processing on the generated message and broadcasting to a relay station,
The method according to claim 1, wherein the message includes information indicating start of an intermediate link area of a next frame.   The message is included in any one of a frame control header (R-FCH: Relay Frame Control Header) message corresponding to the intermediate link area and a MAP message including allocation information of the intermediate link area. The method according to claim 4. A communication method of a base station in a wireless communication system, comprising:
When the relay station is handed over, a process in which the target base station receives intermediate link area information defining an intermediate link area of a frame to be communicated with the relay station from the target base station;
Generating a message including the intermediate link region information of the target base station;
Processing the physical layer and sending the message to the relay station to be handed over.   The message includes at least one of information indicating start of an intermediate link area of the target base station and information indicating a permutation scheme of the intermediate link area. 6. The method according to 6. A communication method of a relay station in a wireless communication system,
Performing a network participation procedure with the base station;
A process of receiving a message including intermediate link area information regarding an intermediate link area in which the base station and the relay station communicate after the network participation procedure;
A relay station operation in a region indicated by the intermediate link region information,
It said message, wherein the containing intermediate region indicator representing the Turkey contains the relay link zone information. A communication method of a relay station in a wireless communication system,
Performing a network participation procedure with the base station;
A process of receiving a message including intermediate link area information regarding an intermediate link area in which the base station and the relay station communicate after the network participation procedure;
A relay station operation in a region indicated by the intermediate link region information,
The method includes a middle region indicator indicating whether one of a GAP and PAPR reduction region has been allocated.   When the message includes the intermediate link region information, a frame control header (FCH) message includes indicator information indicating that the message includes the intermediate link region information. The method of claim 9. A communication method of a relay station in a wireless communication system,
Checking whether a message including change information of an intermediate link area in which a base station and a relay station communicate with each other is received;
Confirming an intermediate link area changed from the message upon receipt of the message;
Performing a relay station operation in the modified intermediate link region,
The method according to claim 1, wherein the message includes information indicating start of an intermediate link area of a next frame.   The message is transmitted by being included in one of a frame control header (R-FCH) message corresponding to an intermediate link region and a MAP message including allocation information of the intermediate link region. Item 12. The method according to Item 11. A communication method of a relay station in a wireless communication system,
When handing over, a process in which the target base station receives a message including intermediate link region information defining an intermediate link region of a frame communicating with the relay station from the target base station;
Confirming the intermediate link area of the target base station from the message;
Performing a relay station operation in the intermediate link area after completing the handover.   The message includes at least one of information indicating start of an intermediate link area of the target base station and information indicating a permutation scheme of the intermediate link area. 14. The method according to 13. A communication method in a wireless communication system,
After the initial connection procedure is completed, the base station transmits a first message including intermediate link area information to the relay station;
The relay station confirming intermediate link region information from the first message received from the base station;
The relay station performs a relay station operation in an area indicated by the intermediate link area information,
The method according to claim 1, wherein the first message includes an intermediate area indicator indicating that the intermediate link area information is included. A communication method in a wireless communication system,
After the initial connection procedure is completed, the base station transmits a first message including intermediate link area information to the relay station;
The relay station confirming intermediate link region information from the first message received from the base station;
The relay station performs a relay station operation in an area indicated by the intermediate link area information,
A method comprising an intermediate area indicator indicating whether one of a GAP and PAPR (Peak to Average Power Ratio) reduction area has been allocated.   When the message includes the intermediate link region information, a frame control header (FCH) message includes indicator information indicating that the message includes the intermediate link region information. The method of claim 16. When the intermediate link area is changed, the base station broadcasts a second message including change information of the intermediate link area to a relay station communicating in the intermediate link area;
The relay station confirming the changed intermediate link area from the second message received from the base station;
The method of claim 15, further comprising the step of the relay station performing a relay station operation in the modified intermediate link area.   The method of claim 18, wherein the second message includes information indicating start of an intermediate link area of a next frame.   The second message is transmitted by being included in one of a frame control header (R-FCH) message corresponding to an intermediate link region and a MAP message including allocation information of the intermediate link region. The method of claim 18. When the relay station is handed over, the base station transmits a third message including intermediate link area information of the handover target base station;
The relay station confirming the intermediate link area of the target base station from the information in the third message received from the base station;
The method of claim 15, further comprising: performing the relay station operation in the intermediate link area of the confirmed target base station after the handover is completed.   22. The third message includes at least one of information indicating start of an intermediate link area of the target base station and information indicating a permutation scheme of the intermediate link area. The method described in 1. A base station apparatus in a wireless communication system,
A message generator for generating a first message including intermediate link area information about an intermediate link area in which the base station and the relay station communicate after the initial connection procedure;
The message from the message generator and physical layer processing, and a transmitter for transmitting to the relay station,
The apparatus according to claim 1, wherein the first message includes intermediate area indicator information indicating that the intermediate link area information is included. A base station apparatus in a wireless communication system,
A message generator for generating a first message including intermediate link area information about an intermediate link area in which the base station and the relay station communicate after the initial connection procedure;
The message from the message generator and physical layer processing, and a transmitter for transmitting to the relay station,
The apparatus of claim 1, wherein the first message includes an intermediate area indicator indicating whether one of a GAP and a PAPR reduction area is allocated.   When the first message includes the intermediate link region information, a frame control header (FCH) message includes indicator information indicating that the first message is a message including intermediate link region information. 25. The apparatus of claim 24. When the intermediate link area is changed, the message generator generates a second message including change information of the intermediate link area;
The apparatus of claim 23, wherein the transmitter performs physical layer processing on the second message and broadcasts it to a relay station communicating in an intermediate link region.   The apparatus of claim 26, wherein the second message includes information indicating start of an intermediate link area of a next frame.   The second message is transmitted by being included in one of a frame control header (R-FCH) message corresponding to an intermediate link region and a MAP message including allocation information of the intermediate link region. 27. The apparatus of claim 26. When the relay station is handed over, the message generator generates a third message including intermediate link area information of the target base station,
The apparatus of claim 23, wherein the transmitter transmits the third message to the handover relay station by performing a physical layer process.   30. The third message includes at least one of information indicating start of an intermediate link area of the target base station and information indicating a permutation scheme of the intermediate link area. The device described in 1. A relay station apparatus in a wireless communication system,
After the initial connection is completed, a first message including intermediate link area information related to an intermediate link area in which the base station and the relay station communicate with each other is received from the base station, and the intermediate link indicated by the intermediate link area information in the first message A control unit that controls the communication unit to perform relay station communication in the area;
A communication unit that communicates with the base station in the intermediate link region,
The apparatus according to claim 1, wherein the first message includes an intermediate area indicator indicating that the intermediate link area information is included. A relay station apparatus in a wireless communication system,
After the initial connection is completed, a first message including intermediate link area information related to an intermediate link area in which the base station and the relay station communicate with each other is received from the base station, and the intermediate link indicated by the intermediate link area information in the first message A control unit that controls the communication unit to perform relay station communication in the area;
A communication unit that communicates with the base station in the intermediate link region,
The apparatus of claim 1, wherein the first message includes an intermediate area indicator indicating whether one of a GAP and a PAPR reduction area is allocated.   When the first message includes the intermediate link region information, a frame control header (FCH) message includes indicator information indicating that the first message is a message including intermediate link region information. 33. The apparatus of claim 32.   When receiving the second message including the change information of the intermediate link area from the base station, the control unit confirms the changed intermediate link area from the second message and relays the relay station in the changed intermediate link area. The apparatus according to claim 31, wherein the communication unit is controlled to perform communication.   The apparatus of claim 34, wherein the second message includes information indicating start of an intermediate link area of a next frame.   The second message is transmitted by being included in one of a frame control header (R-FCH) message corresponding to an intermediate link region and a MAP message including allocation information of the intermediate link region. An apparatus according to claim 34.   When receiving the third message including the intermediate link region information of the target base station to be handed over from the base station, the control unit confirms the intermediate link region of the target base station from the third message, and is confirmed when the handover is completed. The apparatus according to claim 31, wherein the communication unit is controlled to perform relay station communication in an intermediate link area of the target base station.   38. The third message includes at least one of information indicating start of an intermediate link area of the target base station and information indicating a permutation scheme of the intermediate link area. The device described in 1.

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