JP2009528804A - Apparatus and method for supporting relay service in multi-hop relay broadband wireless access communication system - Google Patents

Abstract

An apparatus and method for supporting a relay service in a multi-hop relay broadband wireless access communication system.
At least one of communication between a base station and a first terminal within a service area of the base station and communication between a relay station and a second terminal within a service area of at least one relay station. At least one of a process of configuring a first section of a subframe for performing communication, communication between the base station and at least one relay station, and communication between at least one relay station and another relay station Configuring a second section of a subframe for performing one.
[Selection] Figure 7

Description

  The present invention relates to a multi-hop relay type multi-band wireless access communication system, and more particularly to provide a direct link service and a relay link service synchronously in the multi-hop relay type wide-band radio access communication system. The present invention relates to the apparatus and method.

  One of the most important requirements in the fourth generation communication system is a self-configurable wireless network configuration. A self-configuring wireless network refers to a wireless network that can provide mobile communication services by configuring the wireless network autonomously or in a distributed manner without the control of a central system. Generally, in the fourth generation communication system, in order to enable high-speed communication and accommodate a larger amount of calls, the fourth generation communication system must be composed of cells having a very small radius. In this case, it is expected that the fourth generation communication system cannot be centrally designed. Accordingly, the fourth generation communication system must be able to actively cope with environmental changes such as addition of new base stations while being controlled and constructed in a distributed manner. Therefore, in the fourth generation communication system, a self-configuring wireless network is required.

  In order to practically realize the self-configuration wireless network required in the fourth generation communication system, the technology applied in the ad-hoc network must be introduced into the wireless access communication system. Don't be. A typical example is a multi-hop relay broadband wireless access communication system, in which an ad hoc multi-hop relay technique is introduced into a broadband wireless access network composed of fixed base stations.

  In a general broadband wireless access communication system, communication is performed between a fixed base station (Base station) and a terminal (Mobile station) using a single direct link. A highly reliable wireless communication link can be easily configured between them. However, since the position of the base station is fixed in the broadband wireless access communication system, the flexibility of the wireless network configuration is low. Therefore, it is difficult for the broadband wireless access communication system to provide an efficient service in a wireless environment in which traffic distribution and call request amount change drastically.

  In order to overcome such disadvantages, the broadband wireless access communication system can use a relay service that transmits data in a multi-hop manner by using various peripheral terminals or relay stations. The broadband wireless access communication system using the multi-hop relay system can quickly reconfigure a network in response to a change in communication environment, and can operate the entire wireless network more efficiently. In the broadband wireless access communication system, a relay station is provided between a base station and a terminal, and a multi-hop relay path through the relay station is configured, so that a radio channel having a better channel state can be obtained. Can be provided to the terminal. That is, the broadband wireless communication system provides a higher-speed data channel by providing a service using a multi-hop relay system via a relay station in a cell boundary region where the channel state from the base station is poor. And the cell service area can be expanded.

  FIG. 1 illustrates a structure for providing a service using a multi-hop relay scheme in a general broadband wireless access communication system.

  As shown in FIG. 1, terminals 140, 150, 160, and 170 provided in a broadband wireless access communication system using a multi-hop relay scheme are connected via a base station 100 and first relay stations 110, 120, and 130. Wireless access service can be provided.

  That is, the terminals 140 and 150 provided in the service area 101 of the base station 100 communicate with the base station 100 using the terminal link L1 directly. At this time, the second terminal 150 located in the cell boundary area of the base station 100 and having a poor channel state communicates using the relay terminal link L2 of the second relay station 130, thereby performing a direct terminal link. A data channel faster than L1 can be provided.

  Terminals 160 and 170 located outside the service area 101 of the base station 100 communicate with the base station 100 via the relay terminal link L3 of the first relay station 110. That is, the base station 100 can expand the cell area by providing a communication link to the terminals 160 and 170 located outside the service area using the first relay station 110. At this time, the fourth terminal 170 located in the cell boundary area of the first relay station 110 and having a poor channel state uses the relay terminal link L4 of the second relay station 120 to increase the transmission capacity. Can do.

  As described above, the broadband wireless access communication system is configured to relay the terminal when the terminal is located outside the service area of the base station or when the channel condition is poor due to being located in a shaded area where the shielding phenomenon is severe due to a building or the like. A station is used to provide a superior radio channel to the terminal so as to communicate with the base station. That is, the base station can provide a high-speed data channel by applying a multi-hop relay scheme in a cell boundary area and a shaded area where channel conditions are poor, and can expand the cell service area.

  The relay stations 110, 120, and 130 used in FIG. 1 are a first relay station 110 used to expand a cell service area according to operational capability and a second relay station used to increase capacity. 120 and 130.

  The first relay station 110 is used to expand a cell service area. That is, the terminals 160 and 170 that are difficult to provide services directly from the base station 100 perform synchronization and network entry processes with the base station 100 via the first relay station 110. Accordingly, the first relay station 110 provides the terminals 160 and 170 with the functions required in the initial connection of the terminals 160 and 170, that is, the control information channel (or traffic channel) and the random connection channel in the broadcast form. .

  The second relay stations 120 and 130 relay services to terminals 150 and 170 located in the cell service area in order to increase service capacity. That is, the second terminal 150 is provided with a control information channel and random connection channel information from the base station 100 and is provided with a traffic channel from the second relay station 130. The fourth terminal 170 is provided with a control information channel and random connection channel information from the first relay station 110 and a traffic channel from the second relay station 120.

  In a general broadband wireless access communication system, transmission / reception of information between a base station and a terminal is performed based on a frame as shown in FIG. 2 below via a direct link. Here, FIG. 2 below shows a frame structure for performing transmission / reception of information between the base station and the terminal, and a time division duplex provided from the IEEE (Institut of Electrical and Electronics Engineers) 802.16 standard. A (Time Division Duplex) frame structure is shown as an example.

  FIG. 2 shows a TDD frame structure of a general broadband wireless access communication system.

  As shown in FIG. 2, the time division duplex frame 200 is divided into a downlink subframe 210 and an uplink subframe 220. Also, a TTG (Transmit / Receive Transition Gap), which is a time protection region (Guard region), is inserted between the downlink subframe 201 and the uplink subframe 211, and between the frames, An RTG (Receive / Transmit Transition Gap) is located.

  The downlink sub-frame 210 includes a preamble and common control information in a fixed position (Mandatory slot). That is, a terminal provided in the service area of the base station can acquire the synchronization and control information by receiving the preamble and the common control channel broadcast from a fixed location.

  As described above, the first relay station is located outside the service area of the base station and provides the broadband wireless access service to a terminal or relay station that is difficult to establish a direct link with the base station. Therefore, the first relay station must provide control information, an initial lasing slot, and the like so that the terminal or relay station can perform not only a user traffic service but also a network entry operation. In particular, in order to maintain the compatibility of the terminal, the first relay station has the same structure as the service via the direct link as shown in FIG. 3 below. Must be provided.

  Also, since the relay station performs transmission after receiving a control channel or a traffic channel from the base station or terminal in order to provide the relay service, all transmission / reception operations must be performed within a subframe of a unidirectional link. I must.

  FIG. 3 illustrates a TDD frame structure of a conventional multi-hop relay broadband wireless access communication system.

  As shown in FIG. 3, the unidirectional subframes 300 and 310 are divided into areas 301 and 311 for direct links and areas 303 and 313 for indirect links. That is, a certain section of the sub-frames 300 and 310 is allocated to areas 303 and 313 for providing a relay service using the relay station. At this time, the relay station provides information and data for relaying the service via a direct link area. Here, the areas 303 and 313 for the relay link service are referred to as indirect links.

  For example, the first relay station receives control information and a traffic burst for relay from the base station or terminal in the direct link areas 301 and 311. Thereafter, the first relay station relays control information and traffic bursts from the indirect link regions 303 and 313 to the terminal or base station.

  In addition, the second relay station receives a unicast traffic burst for relay from a terminal or a base station in the direct link areas 301 and 311. Thereafter, the second relay station relays the unicast traffic burst from the indirect link regions 303 and 313 to the terminal or base station.

  When performing communication using the frame structure as shown in FIG. 3, the broadband wireless access communication system uses different frames depending on the entity providing the broadband wireless access service, as shown in FIG. 4 below. Operates asynchronously with timing.

  FIG. 4 shows transmission / reception timings of terminals in a conventional multi-hop relay broadband wireless access communication system.

  As shown in FIG. 4, a terminal provided with a direct link service from the base station performs communication using the direct link area 401 and therefore has the same timing as the BS frame 421. On the other hand, since a terminal provided with a relay link service via a relay station performs communication using the indirect link area 403, it has the same timing as the RS frame 423.

  In a general broadband wireless access communication system, synchronization and handover are performed based on a preamble and control information transmitted to a fixed position in a frame. However, as shown in FIG. 4, since the terminal that provides the service operates asynchronously according to the entity that provides the broadband wireless access service, as shown in FIG. Over and synchronization is difficult.

  FIG. 5 shows a signal flow caused by movement of a terminal in a conventional multi-hop relay broadband wireless access communication system.

  As shown in FIG. 5, when the first terminal 520 provided with service from the base station 500 moves to the service area of the first relay station 510, the first terminal 520 transmits the preamble of the first relay station 510. And control information must be received.

  Further, when the second terminal 530 provided with service from the first relay station 510 moves to the service area of the base station 500, the second terminal 530 receives the preamble and control information of the base station 500. There must be.

  However, as shown in FIG. 3, since the base station 500 and the first relay station 510 operate asynchronously, the first terminal 520 and the second terminal 530 perform the handover after the handover. There is a problem that it is difficult to acquire control information.

  Further, as shown in FIG. 3, since the base station provides services to the terminal and the relay station simultaneously from within the direct link frame, the base station has a degree of freedom with respect to the system configuration for supporting the relay station. There is a problem that it is low.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a frame for efficiently providing terminal handover and synchronization in a multi-hop relay broadband wireless access communication system. An object of the present invention is to provide a configuration method and an apparatus for supporting the method.

  Another object of the present invention is to provide a frame configuration method for increasing the degree of freedom of a relay link and a device for supporting the same in a multi-hop relay broadband wireless access communication system.

  Still another object of the present invention is to configure a subframe as a connection link subframe and a relay link subframe in a multi-hop relay broadband wireless access communication system, and to synchronize the direct link service and the relay link service in a synchronous manner. It is to provide an apparatus and method for providing.

  In order to achieve the above object, according to a first aspect of the present invention, a subframe configuration method for supporting a relay service in a multi-hop relay wireless communication system is provided between first subframes of the subframe. In addition, during the process of forming a subframe for communicating with a terminal at the base station or at least one relay station, and another relay at the base station or at least one relay station between the second section of the subframe. And a process of constructing a subframe for communicating with a station.

  According to a second aspect of the present invention, a subframe configuration method for supporting a relay service in a multi-hop relay radio communication system includes a base station or a relay station during a first interval of the subframe. For the communication between the base station and the relay station, the relay station and the relay station, or the relay station and the terminal, during the process of configuring the subframe for communicating with the terminal and the second section of the subframe Comprising a step of forming a subframe, and a step of forming a subframe for communication between the base station and the terminal, and the relay station and the relay station, during a third interval of the subframe. To do.

  According to a third aspect of the present invention, an operation method of a base station for supporting a relay service in a multi-hop relay wireless communication system uses a first section of the subframe according to a predetermined subframe configuration scheme. And a process of communicating with the terminal and a process of communicating with the relay station using the second interval of the subframe.

  According to a fourth aspect of the present invention, a relay station operating method for supporting a relay service in a multi-hop relay wireless communication system performs network entry using control information received from an upper node. To acquire subframe configuration information for supporting a relay service, and to receive a synchronization channel, control information, and traffic burst from the upper node through the second section of the subframe in the nth frame. And transmitting a synchronization channel and the received control information and traffic burst to the terminal through the first section of the subframe in the (n + 1) th frame.

  According to a fifth aspect of the present invention, an apparatus for supporting a relay service in a multi-hop relay wireless communication system is configured to communicate a signal for a section for communicating with a terminal and a relay station according to a frame configuration scheme. A timing controller that provides a transmission / reception timing signal with a signal for a section; an RF (Radio Frequency) duplexer that separates a signal for a section for communicating with the terminal and a signal for a section for communicating with the relay station; And a transceiver that communicates with the terminal or the relay station according to the timing signal.

  In the present invention, in a broadband wireless access communication system using a multi-hop relay system, signal transmission is time-division multiplexed into a connection link area and a relay link area, and direct and relay services are transparent to the terminal in the form of a synchronous frame. Therefore, handover and synchronization due to the mobility of the terminal is easy, and the intermediate link area where the relay station is provided is made independent of the connection link area, so that the number of hops and the channel There is an advantage that the degree of freedom of the relay link can be increased depending on the environment.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that a specific description of a related known function or configuration may depart from the gist of the present invention, a detailed description thereof will be omitted.

  Hereinafter, the present invention provides a service to a terminal in synchronization with a base station and a relay station in a multi-hop relay wideband wireless access communication system, and increases the degree of freedom of area configuration for the relay service. The technique for raising is demonstrated.

  In the following description, a wireless communication system using a time division duplex and an orthogonal frequency division multiplexing access method will be described as an example, and other multiple connection methods or frequency divisions will be described. The present invention can be similarly applied to a communication system based on duplex division (Frequency Division Duplex). In the following description, the first relay station is assumed to be a high capability relay station that provides a control signal to expand the service area, and the second relay station transmits a traffic burst to increase capacity. The description will be made assuming that the relay station is mainly a low capability relay station.

  In order to provide the direct link service and the relay link service in synchronization with each other at the same timing, the broadband wireless access communication system provides a subframe as a connection link subframe and a relay link subframe as shown in FIG. Divided into frames.

  Here, the connection link means a link for a base station and a relay station to communicate with a terminal, and the relay link means a link for the base station and an upper relay station to communicate with a lower relay station. means.

  In the following description, the connection link subframe will be described as having the same form as the subframe of the IEEE (Institute of Electrical and Electronics Engineers) 802.16 system.

  FIG. 6 shows the structure of a subframe of the multi-hop relay broadband wireless access communication system according to the present invention.

  As shown in FIG. 6, the subframe 600 is divided into a connection link subframe 610 and a relay link subframe 620. Here, the connection link subframe 610 and the relay link subframe 620 are divided by time slots.

  In the case of the downlink, the subframe 600 is divided into a connection link subframe 610 and a relay link subframe 620 according to a signal destination. That is, a signal is transmitted from the base station or the relay station to the terminal during the connection link subframe 610, and the base station or the upper relay station transmits a signal to the lower relay station during the relay link subframe 620. To do.

  In the uplink, the subframe 600 is divided into a connection link subframe 610 and a relay link subframe 620 according to the signal origin. That is, during the connection link subframe 610, the terminal transmits a signal to the base station or relay station, and during the relay link subframe 620, the lower relay station transmits the base station or upper relay station. Send a signal to

  At this time, during the connection link subframe 610, the base station and the relay station communicate with the terminal in a transparent manner. That is, the base station and the relay station provide services so that the terminal cannot recognize the difference between the direct link service and the relay link service, and can recognize that the terminal communicates with the base station. In addition, when the broadband wireless access communication system includes multiple hops, the relay link subframe 620 can be divided into a plurality of regions according to the multiple hops.

  As shown in FIG. 6, the broadband wireless access communication system can form a frame as shown in FIG. 7 using a subframe composed of a connection link subframe and a relay link subframe. it can.

  FIG. 7 shows a frame configuration in the multi-hop relay broadband wireless access communication system according to the embodiment of the present invention.

  As shown in FIG. 7, the frame is divided into a downlink subframe 700 and an uplink subframe 710. At this time, the downlink subframe 700 and the uplink subframe 710 are time-multiplexed into the connection link subframes 701 and 711 and the relay link subframes 703 and 713 as shown in FIG.

  The subframes 700 and 710 of the frame are used to transparently provide the terminal with a start position of a frame preceded by a preamble and a TTG (Transmit / Receive Transition Gap) position that is a time protection region (Guard region). The link subframes 701 and 711 are positioned before the relay link subframes 703 and 713.

  Between the connection link subframes 701 and 711, the base station and the relay station communicate with a terminal that provides a service. At this time, the connection link sub-frames 701 and 711 may include frequency division multiplexing, space division multiplexing, or orthogonal frequency for the direct terminal link service provided by the base station 720 and the relay terminal link service provided by the first relay station 730. Provided in the form of division multiplexing.

  In addition, in the connection link subframes 701 and 711, the first relay station 730 transmits control information and traffic bursts to the terminal with the same structure as the direct terminal link service provided by the base station 720 in order to perform relaying transparently. I will provide a. At this time, the second relay station is assigned bursts 705 and 707 of a certain area from the base station 720 or the first relay station 730, and provides a unicast traffic channel to the terminal.

  Between the relay link subframes 703 and 713, the base station and the upper relay station communicate with the lower relay station. At this time, the relay link subframes 703 and 713 have a fixed length, or may change dynamically according to the cell environment. Here, the relay link sub-frames 703 and 713 may be applied with advanced technology having new functions and uses, and thus the detailed configuration is omitted.

  When the broadband wireless access communication system is extended to multiple hops, the relay link subframes 703 and 713 can be time-multiplexed according to the multiple hop link as shown in FIG.

  FIG. 8 and FIG. 9 show the configuration of the subframe of the relay link in the multi-hop relay wideband radio access communication system according to the embodiment of the present invention. In the following description, the relay link subframe may be composed of control channels and traffic channels having various structures.

  8 and 9 show a frame structure in which the relay link subframes 803 and 813 are multiplexed according to the number of hops.

  First, as shown in FIG. 8, the broadband wireless access communication system multiplexes the relay link subframes 803 and 813 in a direction in which the number of hops decreases in accordance with the number of hops constituting the system. That is, the relay link subframes 803 and 813 are multiplexed such that the link between the (n-1) hop relay station and the n hop relay station precedes the base station and the 1 hop relay station link.

  Next, as shown in FIG. 9, the broadband wireless access communication system multiplexes the relay link subframes 803 and 813 in a direction in which the number of hops increases according to the number of hops constituting the system. That is, the relay link subframes 803 and 813 are multiplexed such that the link between the base station and the 1-hop relay station precedes the link between the (n−1) -hop relay station and the n-hop relay station. Here, the number of hops of the multi-hop relay station refers to the next hop of the base station as one hop. The hop number of the relay station of the next hop number is increased.

  As shown in FIGS. 7 to 9, the base station and the relay station divide the unidirectional subframe into a connection link subframe and a relay link subframe, and provide a service to a terminal or a lower relay station. . At this time, the base station and the relay station have the same frame start timing as shown in FIG. That is, the base station and the relay station provide the connection link service in synchronization with the terminal at the same timing.

  FIG. 10 shows the timings of a base station, a terminal, and a relay station in a multi-hop relay broadband wireless access communication system according to an embodiment of the present invention. In the following description, a system having a two-hop link will be described as an example. Accordingly, the first relay station and the second relay station provide a one-hop relay service to different terminals.

  As shown in FIG. 10, in the downlink subframe 900, the base station 920 transmits control information and a traffic burst to a terminal providing a service during a connection link subframe 901 section (D_t1 section). Further, the base station 920 transmits control information and a traffic burst to the relay stations 930 and 940 during the relay link subframe 903 section (D_t3 section).

  The first relay station 940 transmits control information and a traffic burst to a terminal that provides a service during a connection link subframe 901 interval (D_t1 interval). In addition, the first relay station 940 receives control information and a traffic burst necessary for relay from the base station 920 during a relay link subframe 903 (D_t3 section). In this case, when the broadband wireless access communication system is expanded to 3 hops or more and a 2-hop relay station is provided, the first relay station 940 multiplexes the relay link subframe 903 section to obtain a predetermined section. During this period, control information and traffic burst are transmitted to the next hop relay station. At this time, the size of the time slot for multiplexing the relay link subframe 903 is adaptively determined according to the number of multiplexed hops and the channel state.

  The second relay station 930 configures the control channel section D_t2 as null in the connection link subframe 901 section, and transmits a unicast traffic burst to the terminal during the remaining section (D_t1-D_t2 section). In addition, control information and a traffic burst necessary for performing the relay service are received from the base station 920 during the relay link subframe 903 (D_t3).

  The terminal 950 receives a control channel and a traffic burst from a base station or a relay station during a connection link subframe 901 interval. The terminal 950 operates in a standby mode (Idle) during the relay link subframe 903. That is, the terminal 950 recognizes and ignores the relay link subframe 903 section as an area that is not allocated to itself.

  Meanwhile, in the uplink subframe 910, the base station 920 receives initial ranging information and a traffic burst from the terminal during the connection link subframe 911 interval (U_t1 interval). Also, the base station 920 receives initial ranging information and traffic bursts from the relay stations 930 and 940 during a relay link subframe 913 (U_t3 section).

  The first relay station 940 receives initial ranging information and a traffic burst from a terminal in order to perform a relay link service during a connection link subframe 911 interval (U_t1 interval). Also, the first relay station 940 transmits the initial ranging information and traffic burst to the base station 920 during a relay link subframe 913 (U_t3 section). At this time, the first relay station 940 compensates for a delay generated from the radio channel and transmits a signal.

  The second relay station 930 configures a control channel section (U_t2) as null during a connection link subframe 911 section, and transmits a traffic burst from the terminal to perform a relay service during the remaining section. Receive (U_t1-U_t2 section). Also, the second relay station 930 transmits a unicast traffic burst to the base station 920 during a relay link subframe 913 (U_t3 period). At this time, the second relay station 930 compensates for a delay generated from the radio channel and transmits a signal.

  The terminal 950 transmits initial ranging information and a traffic burst to the base station or the relay station during a connection link subframe 911 period (U_t1 period). At this time, the terminal 950 compensates for a delay generated from the radio channel and transmits a signal.

  Also, the terminal 930 ignores the relay link subframe 913 as an area that is not allocated to the terminal 950.

  As described above, in the unidirectional subframe, the relay station has to change its operation. Therefore, a time protection area (eg, RSTTG, RSRTG) is required for the downlink subframe 900 and the uplink subframe 910. For example, the time protection area may be configured such that the first symbol of the relay link is configured with a preamble having a short length in the downlink subframe, and the relay station performs operation change during the remaining period. can do. Here, the preamble having the short length is generated by reducing the number of repetitive sequences constituting the preamble.

  As yet another method, the base station can form a certain gap between the connection link subframe 901 and the relay link subframe 903 so that the relay station can change its operation.

  FIG. 11 shows a frame configuration in a multi-hop relay broadband wireless access communication system according to another embodiment of the present invention. In the following description, the relay link subframe and the connection link subframe have the same configuration in the frame.

  As shown in FIG. 11, in the two-hop link system, the downlink subframe 1000 and the uplink subframe 1010 are composed of connection link subframes 1001 and 1011 and relay link subframes 1003 and 1013.

  In the connection link subframes 1001 and 1011, a direct terminal link service provided by a base station and a relay terminal link service provided by a relay station are provided in frequency division multiplexing, space division multiplexing, and orthogonal frequency division multiple access forms. The

  The relay link subframes 1003 and 1013 are configured from an area for the base station or the upper relay station to communicate with the lower relay station.

  In the above-described embodiment, the frame structure for supporting the relay service when the broadband wireless access communication system includes two hops has been described. If the broadband wireless access communication system is composed of three or more hops, relay services can be provided by multiplexing relay link subframes as shown in FIGS. For example, in a broadband wireless access communication system composed of three or more hops, the frame structure shown in FIGS. 8 and 9 can be embodied as shown in FIG. In the following description, FIG. 12 below will be described with an example in which the relay link subframe is multiplexed into two regions in order to provide a relay service with multiple hops.

  FIG. 12 shows a frame configuration of a broadband wireless access communication system using a relay scheme of 3 hops or more according to an embodiment of the present invention. In the following description, the base station, the relay station, and the terminal will be described as an example in which communication is performed by forming a spatially multiplexed frame at one frequency. The first relay station means a 1-hop relay station that receives data directly from the base station and performs a relay service. The second relay station is a two-hop relay station that receives data that has passed through the base station and the first relay station and performs a relay service.

  As shown in FIG. 12, the jth frame 1100 includes a downlink subframe 1110 and an uplink subframe 1120. At this time, the sub-frames 1110 and 1120 are divided into first sections 1111 and 1121, second sections 1113 and 1123, and third sections 1115 and 1125, respectively. Here, the second sections 1113 and 1123 and the third sections 1115 and 1125 are sections in which the relay link subframes 803 and 813 of FIG. 8 are multiplexed. At this time, the first sections 1111 and 1121 include a base station for the base station or the relay station to communicate with the terminal, a subframe for the terminal link, and a subframe for the relay station and the terminal link. Composed.

  Next, the second sections 1113 and 1123 include a subframe for a base station and a relay station link, and a subframe for a relay station and a terminal link. When the system is composed of three or more hops, the second sections 1113 and 1123 include a subframe for the base station and the relay station link, a subframe for the relay station and the relay station, and a relay station. And a subframe for the terminal.

  Finally, the third sections 1115 and 1125 include a subframe for a base station and a terminal link, and a subframe for a relay station and a relay station link.

  Further, a TTG (Transmit / Receive Transmission Gap) that is a time protection region exists between the downlink subframe 1110 and the uplink subframe 1120.

  When the j-th frame 1100 configured as described above is used to support a relay service configured from multiple hops, the base station 1130 may determine whether the first section 1111 of the downlink subframe 1110 Downlink data is transmitted to the first terminal 1160 that provides services to the third section 1115. Further, the base station 1130 transmits downlink data to the first relay station 1140 during the second interval 1113.

  Thereafter, the base station 1130 receives uplink data from the first terminal 1160 during the first interval 1121 and the third interval 1125 of the uplink subframe 1120. In addition, the base station 1130 receives uplink data from the first relay station 1140 during the second interval 1123.

  The first relay station 1140 transmits downlink data to a second terminal 1170 that provides a service during the first period 1111 of the downlink subframe 1110. Also, the first relay station 1140 receives downlink data from the base station 1130 during the second interval 1113. In addition, the first relay station 1140 transmits downlink data to the second relay station 1150 during the third interval 1115.

  Thereafter, the first relay station 1140 receives uplink data from the second terminal 1170 during the first period 1121 of the uplink subframe 1120. In addition, the first relay station 1140 transmits uplink data to the base station 1130 during the second interval 1123. Also, the first relay station 1140 receives uplink data from the second relay station 1150 during the third interval 1125.

  Next, the second relay station 1150 transmits downlink data to a third terminal 1180 that provides a service between the first section 1111 and the second section 1113 of the downlink subframe 1110. Also, the second relay station 1150 receives downlink data from the first relay station 1140 during the third interval 1115.

  Thereafter, the second relay station 1150 receives uplink data from the third terminal 1180 between the first interval 1121 and the second interval 1123 of the uplink subframe 1120. In addition, the second relay station 1150 transmits uplink data to the first relay station 1140 during the third interval 1125. Here, when the system is composed of three or more hops, the second relay station 1150 may communicate with a lower relay station that is not the third terminal 1180 during the second section 1113, 1123. it can. That is, when the system is configured with three hops, the second relay station 1150 is a terminal hop relay station, and thus the third terminal 1180 that is not a lower relay station between the second sections 1113 and 1123 Communicate.

  The first terminal 1160, the second terminal 1170, and the third terminal 1180 receive downlink data from a subject to which a communication link is connected during the downlink subframe 1110 of the j-th frame 1100. Also, the terminals 1160, 1170, and 1180 transmit uplink data to the subject to which the communication link is connected during the uplink subframe 1120.

  For example, the first terminal 1160 receives downlink data from the base station 1130 between the first section 1111 and the third section 1115 of the downlink subframe 1110. Further, the first terminal 1160 transmits uplink data to the base station 1100 between the first interval 1121 and the third interval 1125 of the uplink subframe 1120.

  Next, the second terminal 1170 receives downlink data from the first relay station 1140 during the first period 1111 of the downlink subframe 1110. Also, uplink data is transmitted to the first relay station 1140 during the first interval 1121 of the uplink subframe 1120.

  Finally, the third terminal 1180 receives downlink data from the second relay station 1150 during the first interval 1111 and the second interval 1113 of the downlink subframe 1110. In addition, uplink data is transmitted to the second relay station 1150 between the first section 1121 and the second section 1123 of the uplink subframe 1120.

  When the broadband wireless access communication system is configured as shown in FIG. 12, when each subframe has the same structure as the IEEE 802.16 standard, it is configured as shown in FIGS. 13 and 14 below. . At this time, FIG. 13 below shows a frame structure of the base station and the first relay station, and FIG. 14 below shows a frame structure of the second relay station and the terminal.

  FIG. 13 shows a frame configuration of a base station and a first relay station in a broadband wireless access communication system using a relay scheme of 3 hops or more according to an embodiment of the present invention.

  As illustrated in FIG. 13, the j-th frame includes a downlink subframe 1200 and an uplink subframe 1220. At this time, the sub-frames 1200 and 1220 are divided into first sections 1211 and 1221, second sections 1213 and 1223, and third sections 1215 and 1225, respectively.

  Between the downlink subframe 1200 and the uplink subframe 1220, there is a TTG (Transmit / Receive Transmission Gap) that is a time protection region.

  As shown in FIG. 13, during the first section 1211 of the downlink subframe 1200, the base station 1230 and the first relay station 1240 transmit to terminals provided in their service areas. Construct a downlink subframe. At this time, the downlink subframe is sequentially composed of a preamble for synchronization of the terminal, control information, and a downlink burst. Here, the preamble and the control information have fixed positions.

  During the second interval 1213, the base station 1230 constitutes a downlink subframe for transmission to the first relay station 1240. Here, the downlink subframe is sequentially composed of a synchronization channel for synchronization of the first relay station 1240, control information, and a downlink burst.

  In addition, during the second interval 1213, the first relay station 1240 receives a signal transmitted by the base station 1230.

  During the third period 1215, the base station 1230 switches to a standby mode or configures a downlink subframe for transmission to the first terminal. At this time, the downlink subframe includes a downlink burst.

  Also, during the third interval 1215, the first relay station 1240 constitutes a downlink subframe for transmission to the second relay station 1250. That is, during the third section 1215, the upper relay station forms a downlink subframe for transmission to the lower relay station. Here, the downlink subframe includes a preamble for synchronization of the lower relay station, control information, and a downlink burst.

  Next, in the first section 1221 of the uplink subframe 1220, the base station 1230 and the first relay station 1240 receive control information (eg, ranging signal) and uplink burst from terminals provided in the respective service areas. And receive.

  During the second period 1223, the first relay station 1240 constitutes an uplink subframe for transmission to the base station 1230. At this time, the base station 1230 receives a signal transmitted by the first relay station 1240.

  During the third period 1225, the base station 1230 operates in a standby mode or receives a signal transmitted by the first terminal. In addition, the first relay station 1240 receives a signal transmitted by the second relay station 1250. That is, during the third interval 1225, the upper relay station receives a signal from the lower relay station.

  FIG. 14 shows a configuration of a second relay station and a terminal frame in a broadband wireless access communication system using a relay scheme of 3 hops or more according to an embodiment of the present invention.

  As shown in FIG. 14, the j-th frame includes a downlink subframe 1300 and an uplink subframe 1320. At this time, the sub-frames 1300 and 1320 are divided into first sections 1311 and 1321, second sections 1313 and 1323, and third sections 1315 and 1325, respectively.

  Between the downlink subframe 1300 and the uplink subframe 1320, there is a TTG (Transmit / Receive Transmission Gap) which is a time protection area.

  As shown in FIG. 14, between the first section 1311 and the second section 1313 of the downlink subframe 1300, the second relay station 1350 is a down link for transmission to a third terminal provided in a service area. Construct a link subframe. Here, the downlink subframe configured during the first period 1311 is sequentially configured with a preamble for synchronization of the third terminal, control information, and a downlink burst. In addition, the downlink subframe configured during the second period 1313 includes a downlink burst.

  During the third period 1315, the second relay station 1350 receives a signal from the first relay station 1340.

  Also, in the downlink subframe 1300, the terminal receives a downlink subframe from the subject of each service area.

  Next, between the first interval 1321 and the second interval 1323 of the uplink subframe 1320, the second relay station 1350 receives control information (eg, ranging signal) and an uplink burst from the third terminal. To do.

  During the third period 1325, the second relay station 1350 constitutes an uplink subframe for transmission to the first relay station 1340. Here, the uplink subframe is sequentially composed of control information and an uplink burst.

  In addition, the terminal configures an uplink subframe to be transmitted to the subject of the service area of each terminal in the first section 1321. Here, the uplink subframe is sequentially composed of control information and an uplink burst.

  In the second section 1323 and the third section 1325, the terminal configures an uplink subframe according to the subject of each service area. For example, the first terminal 1360 that communicates with the base station 1330 configures an uplink subframe to be transmitted to the base station 1330 in the third section 1325. In addition, the third terminal that communicates with the second relay station 1350 configures an uplink subframe to be transmitted to the second relay station 1350 in the second section 1323.

  When the broadband wireless access communication system is composed of 3 hops or more and a lower relay station is connected to the second relay station 1350, the second relay station 1350 is connected between the second sections 1313 and 1323. And communicate with the lower relay station that is not the third terminal.

  In the above-described embodiment, the synchronization channel is positioned in the preceding stage of the first interval, the second interval, and the third interval. In another embodiment, the synchronization channel can be positioned after the second section and the third section.

  In the following description, an operation procedure of the base station and the relay station for performing communication using the frame structure configured as described above in the broadband wireless access communication system will be described.

  FIG. 15 shows an operation procedure of the base station in the multi-hop relay broadband wireless access communication system according to the embodiment of the present invention.

  As shown in FIG. 15, first, in step 1401, the base station allocates resources to the connection link subframe section 701 and the relay link subframe section 703 constituting the frame. Here, the connection link subframe section 701 and the relay link subframe section 703 may be fixedly determined or may be adaptively changed according to the service environment. If there is no relay station in the service area, the section for the relay link can be omitted.

  After allocating resources for the connection link subframe section 701 and the relay link subframe section 703, the base station proceeds to step 1403 to communicate with the terminal through the connection link subframe section 701.

  Thereafter, the base station proceeds to step 1405 and communicates with the relay station using the relay link subframe section 703.

  For example, in the downlink period, the base station transmits control information and a traffic burst to the terminal during a connection link subframe period 701. Thereafter, the base station transmits control information and a traffic burst to the relay station during the relay link subframe period 703.

  In the uplink period, the base station receives initial ranging information and a traffic burst from the terminal during a connection link subframe period 701. Thereafter, the base station receives initial ranging information and a traffic burst from the relay station during a relay link subframe period 703.

  Thereafter, the base station ends the present algorithm.

  FIG. 16 shows an operation procedure of the relay station in the multi-hop relay broadband wireless access communication system according to the embodiment of the present invention.

  As shown in FIG. 13, first, when the power is turned on in step 1501, the relay station checks whether a preamble and control information are received from the base station.

  When the preamble and control information are received, the RS proceeds to step 1503 and performs an initialization operation for entering the network using the received preamble and control information. At this time, the relay station performs an initial operation in the same manner as the terminal, and performs an initial operation for entering the network via a connection link that is not a relay link. After the initial operation, the relay station sets a relay link through the relay link information acquired through the initial operation. At this time, the relay station may perform the network entry initial operation via the relay link, instead of performing the initial operation using the connection link.

  Thereafter, the relay station supports the broadband service by setting the relay link and the connection link according to the operation capability of the base station and the relay capability of the relay station over steps 1505 and 1507. For example, the relay station receives control information and a traffic burst for the relay service from the base station or the upper relay station during the relay link subframe section 703. Thereafter, the relay station transmits the control information and the traffic burst to the terminal via the connection link subframe section 701 in the next frame. When a lower relay station exists in the relay station, the relay station can transmit the control information and the traffic burst to the lower relay station via the relay link subframe 703.

  Thereafter, the relay station ends the present algorithm.

  In the above-described embodiment, the method for the relay station to communicate with the base station has been described as an example. When the relay station communicates with the upper relay station, the relay station operates in the same manner as the method in which the relay station communicates with the base station.

  In the broadband wireless access communication system, the block configurations of a base station and a relay station that perform communication using a subframe composed of the connection link subframe and the relay link subframe are the same. Therefore, the following description will be given taking the block configuration of the base station as an example, and the block configuration of the relay station will be omitted.

  In the following description, the base station is configured by separating a transmission / reception device for a connection link for communicating with a terminal and a transmission / reception device for a relay link for communicating with a relay station. However, the base station can support the connection link and the relay link with a single transmission / reception device.

  FIG. 17 shows a block configuration of a base station in a multi-hop relay broadband wireless access communication system according to the present invention.

  As shown in FIG. 17, the base station includes a first transmission / reception device 1601 for a relay link, a second transmission / reception device 1603 for a connection link, a timing controller 1605, and an RF duplexer (Radio Frequency Duplexer) 1607, An antenna 1609 is provided. Here, since the first transmission / reception device 1601 and the second transmission / reception device 1603 have the same configuration, the description of the second transmission / reception device 1603 is omitted.

  The first transmission / reception device 1601 includes a transmission device 1611, a reception device 1621, and an RF switch 1631.

  The transmission device 1611 includes a frame generator 1613, a resource mapper 1615, a modulator 1617, and a digital / analog converter 1619.

  The frame generator 1613 forms a relay link subframe for transmitting control information and a traffic burst to the relay station. At this time, the frame generator 1643 of the second transmitter 1641 constitutes a connection link subframe for transmitting the control information and the traffic burst to the terminal.

  The resource mapper 1615 assigns and outputs the relay link subframe provided from the frame generator 1613 to the burst of each link assigned to each subframe.

  The modulator 1617 modulates a subframe assigned to the burst of each link provided from the resource mapper 1615 according to a corresponding modulation level (for example, MCS (Modulation and Coding Scheme) level). The digital / analog converter 1619 converts the digital signal provided from the modulator 1617 into an analog signal, up-modulates the analog baseband signal into a high-frequency signal, and outputs the high-frequency signal to the RF switch 1631.

  The receiving device 1621 includes an analog / digital converter 1623, a demodulator 1625, a resource demapper 1627, and a frame extractor 1629.

  The analog / digital converter 1623 is provided with an analog signal that is converted into a baseband signal by reducing the frequency of the signal received from the relay station via the RF switch 1631 during the relay link subframe period. , Convert to digital signal.

  The demodulator 1625 demodulates and outputs the digital signal provided from the analog / digital converter 1623 according to the modulation level.

  The resource demapper 1627 extracts the actual subframe assigned to the burst of each link provided from the demodulator 1625.

  The frame extractor 1629 extracts a subframe corresponding to the receiver 1621 from the subframe provided from the resource demapper 1627. For example, the frame extractor 1629 extracts a relay link subframe of an uplink subframe received from the relay station. At this time, the frame extractor 1659 of the second receiving device 1651 extracts the connection link subframe of the uplink subframe received from the terminal.

  The RF switch 1631 connects the transmission / reception devices 1611 and 1621 and the RF duplexer 1607 to the relay link service section under the control of the timing controller 1605.

  The timing controller 1605 controls transmission / reception timings of a section for the relay link service and a section for the connection link service.

  The RF duplexer 1607 separates the RF signal received through the antenna 1609 into transmission / reception devices 1601 and 1603 according to the section for the relay link service and the section for the connection link service. Send.

  Although the specific embodiments have been described in the detailed description of the present invention, various modifications can be made without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the above-described embodiment, but should be determined not only by the claims but also by the equivalents of the claims.

1 is a diagram illustrating a structure for providing a service using a multi-hop relay scheme in a general broadband wireless access communication system. FIG. 1 is a diagram illustrating a TDD frame structure of a general broadband wireless access communication system. FIG. FIG. 2 is a diagram illustrating a TDD frame structure of a conventional multi-hop relay broadband wireless access communication system. It is a figure which shows the transmission / reception timing of the terminal in the broadband wireless access communication system of the multihop relay system by a prior art. It is a figure which shows the signal flow by the movement of the terminal in the broadband wireless access communication system of the multihop relay system by a prior art. 1 is a diagram illustrating a subframe configuration of a multi-hop relay broadband wireless access communication system according to the present invention. FIG. It is a figure which shows the frame structure in the wideband radio | wireless access system of the multihop relay system by embodiment of this invention. 1 is a diagram illustrating a subframe configuration of a relay link in a multi-hop relay broadband wireless access communication system according to an embodiment of the present invention. FIG. 1 is a diagram illustrating a subframe configuration of a relay link in a multi-hop relay broadband wireless access communication system according to an embodiment of the present invention. FIG. FIG. 5 is a diagram illustrating timings of a base station, a terminal, and a relay station in a multi-hop relay broadband wireless access communication system according to an embodiment of the present invention. It is a figure which shows the frame structure in the wideband radio | wireless wireless access communication system of the multihop relay system by other embodiment of this invention. It is a figure which shows the frame structure of the wideband radio | wireless access communication system which uses the relay system of 3 hops or more by embodiment of this invention. It is a figure which shows the structure of the flame | frame of a base station and a 1st relay station in the broadband wireless access communication system which uses the relay system of 3 hops or more by embodiment of this invention. It is a figure which shows the structure of the frame of the 2nd relay station and terminal in the broadband wireless access communication system which uses the relay system of 3 hops or more by embodiment of this invention. It is a figure which shows the operation | movement procedure of the base station in the broadband wireless access communication system of the multihop relay system by embodiment of this invention. It is a figure which shows the operation | movement procedure of the relay station in the broadband wireless access communication system of the multihop relay system by embodiment of this invention. FIG. 2 is a diagram illustrating a block configuration of a base station in a multi-hop relay broadband wireless access communication system according to the present invention.

Claims (40)

A subframe configuration method for supporting a relay service in a multi-hop relay wireless communication system, comprising:
Configuring a subframe for communicating with a terminal at a base station or at least one relay station during a first interval of the subframe;
Forming a sub-frame for communicating with another relay station at the base station or at least one relay station during a second interval of the sub-frame.   The method of claim 1, wherein the first and second sections of the subframe are divided by time division or frequency division.   The first section of the subframe comprises at least one of a subframe for a base station-terminal link and a subframe for a relay station-terminal link. Method.   The subframe for the base station-terminal link and the subframe for the relay station-terminal link are a frequency division multiple access, a spatial division multiple access, an orthogonal frequency. The method according to claim 3, wherein the division is performed using any one of divisional frequency division multiplexing access (Orthogonal Frequency Division Multiplexing Access).   The method according to claim 3, wherein the subframe for the base station-terminal link and the subframe for the relay station-terminal link are composed of the same structure.   The method of claim 3, wherein the relay station comprises at least one of a first relay station that provides a synchronization channel and a second relay station that does not provide the synchronization channel.   The method of claim 6, wherein the second relay station configures a synchronization channel and a control channel period of a subframe for the relay station-terminal link as a null.   The method of claim 1, wherein the second interval of the subframe comprises a subframe for a base station-relay station link and a subframe for at least one relay station-relay station link. .   The method of claim 8, wherein the subframe for the base station-relay station link and the subframe for the relay station-relay station link are multiplexed by time division or frequency division.   The method of claim 1, wherein the first and second sections of the subframe have a fixed size or a dynamic size depending on a service environment.   The method according to claim 1, wherein a time protection area is allocated between the first and second periods of the subframe to change operation of the relay station. A subframe configuration method for supporting a relay service in a multi-hop relay wireless communication system, comprising:
Configuring a subframe for communicating with a terminal at a base station or a relay station during a first interval of the subframe;
During the second section of the subframe, a process of configuring a subframe for communication between the base station and the relay station, the relay station and the relay station, or the relay station and the terminal;
Forming a subframe for communicating at least one of the base station and the terminal and the relay station and the relay station during a third interval of the subframe. .   The method of claim 12, wherein the first section, the second section, and the third section of the subframe are divided by time division or frequency division.   The first section of the subframe comprises at least one of a subframe for a base station-terminal link and a subframe for a relay station-terminal link. Method.   The subframe for the base station-terminal link and the subframe for the relay station-terminal link use any one of frequency division multiplex connection, space division multiplex connection, and orthogonal frequency division multiplex connection. The method according to claim 14, wherein the classification is performed.   The method according to claim 14, wherein the subframe for the base station-terminal link and the subframe for the relay station-terminal link are composed of the same structure.   The second section of the subframe includes at least one of a subframe for a base station-relay station link, a subframe for a relay station-relay station, and a subframe for a relay station-terminal link. The method according to claim 12, wherein:   The subframe for the base station-relay station link, the subframe for the relay station-relay station, and the subframe for the relay station-terminal link are distinguished by time division or frequency division. The method according to claim 17.   The third section of the subframe comprises at least one of a subframe for a base station-terminal link and a subframe for a relay station-relay station link. the method of.   The method of claim 19, wherein the subframe for the base station-terminal link and the subframe for the relay station-relay station link are distinguished by time division or frequency division.   [13] The first section, the second section, and the third section of the subframe have a fixed size or a dynamic size according to a service environment. Method.   The method of claim 12, wherein the first channel of the subframe has a synchronization channel located in a previous stage.   The method of claim 12, wherein the second channel and the third segment of the subframe position a synchronization channel in a preceding stage or a succeeding stage. A base station operating method for supporting a relay service in a multi-hop relay wireless communication system,
Communicating with a terminal using a first section of the subframe according to a predetermined subframe configuration scheme;
And communicating with a relay station using the second section of the subframe.   The method of claim 24, wherein the first and second intervals have a fixed size or a dynamic size depending on a service environment. When the first section and the second section have dynamic sizes, further comprising allocating resources for the first section and the second section;
26. The method according to claim 25, wherein communication is performed using the first section and the second section according to the resource allocation information.   The method of claim 24, wherein a time protection area is allocated between the first interval and the second interval.   The method of claim 24, wherein the first and second intervals are divided by time division or frequency division.   The method of claim 24, wherein the first section includes a synchronization channel in a preceding stage.   The method according to claim 24, wherein the second interval includes a synchronization channel in a preceding stage or a succeeding stage. A relay station operating method for supporting a relay service in a multi-hop relay wireless communication system,
A process of acquiring subframe configuration information for supporting a relay service by performing network entry using control information received from an upper node;
receiving a synchronization channel, control information and a traffic burst from the upper node via the second section of the subframe in the nth frame;
transmitting a synchronization channel and the received control information and traffic burst to a terminal through a first interval of the subframe in an (n + 1) th frame.   The method of claim 31, wherein the relay station comprises at least one of a first relay station that provides a synchronization channel and a second relay station that does not provide the synchronization channel.   The method of claim 32, wherein the second relay station configures a synchronization channel and a control channel section as nulls.   The method of claim 31, wherein the upper node comprises a base station or an upper relay station. The network entry process includes:
In accordance with a predetermined subframe configuration scheme, a process of receiving control information from the upper node through a section for the upper node to communicate with a terminal;
The method according to claim 31, comprising performing a network entry procedure for the upper node using the received control information. The network entry process includes:
The process of receiving control information from the upper node through a section for the upper node to communicate with the relay station according to a predetermined subframe configuration scheme;
The method according to claim 31, comprising performing a network entry procedure for the upper node using the received control information. An apparatus for supporting a relay service in a multi-hop relay wireless communication system,
A timing controller for providing a transmission / reception timing signal of a signal for a section for communicating with a terminal according to a frame configuration scheme and a signal for a section for communicating with a relay station;
An RF (Radio Frequency) duplexer that separates a signal for a section for communicating with the terminal and a signal for a section for communicating with the relay station;
And a transmitter / receiver that communicates with the terminal or the relay station according to the timing signal.   38. The apparatus of claim 37, wherein the transceiver comprises a first transceiver for communicating with the terminal and a second transceiver for communicating with the relay station. The first transceiver is
A transmitter for forming and transmitting a subframe for transmitting a signal to the terminal according to the timing signal;
A receiver that receives a signal from the terminal according to the timing signal and restores data;
39. The apparatus according to claim 38, comprising: a switch that connects the transceiver and the RF duplexer in accordance with control of the timing controller. The second transceiver is
A transmitter for forming and transmitting a subframe for transmitting a signal to the relay station according to the timing signal;
In response to the timing signal, a receiver that receives a signal from the relay station and restores data;
39. The apparatus according to claim 38, comprising: a switch that connects the transceiver and the RF duplexer in accordance with control of the timing controller.

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