KR101501155B1 - Apparatus and method for allocating dedicated access zone to relay station in a multi-hop relay broadband wireless access communication system - Google Patents

Abstract

The present invention relates to an apparatus and method for allocating a dedicated access area to a relay station in a broadband wireless access communication system using a multi-hop relay scheme. A relay method of a relay station according to the present invention includes the steps of relaying communication between a base station and a terminal, determining whether a dedicated resource is required for communication with the terminal, and, when the dedicated resource is required, And a step of transmitting the dedicated access area request message to the base station.

Relay, access area, dedicated resource

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for allocating a dedicated access area to a relay station in a broadband wireless access communication system, and an apparatus and a method for allocating a dedicated access area to a relay station in a broadband wireless access communication system.

The present invention relates to a multi-hop relay broadband wireless access communication system, and more particularly, to an apparatus and method for allocating a dedicated access area for communication with a terminal to a relay station performing distributed scheduling.

In a 4th Generation (4G) communication system, which is a next generation communication system, services having various Quality of Service (QoS) with a transmission rate of about 100 Mbps are provided to users Active research is underway. In particular, in the current 4G communication system, a broadband wireless connection such as a wireless local area network (LAN) system and a wireless metropolitan area network (MAN) (IEEE) 802.16d communication system and an IEEE 802.16e communication system. The IEEE 802.16e communication system is a communication system that is based on the IEEE 802.16e standard.

The IEEE 802.16d communication system and the IEEE 802.16e communication system use Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiple Access (OFDM) for a physical channel, : Hereinafter referred to as OFDMA). The IEEE 802.16d communication system considers only a single cell structure in a state where a subscriber station (SS) is fixed, that is, the SS does not consider mobility at all. Alternatively, the IEEE 802.16e communication system considers the mobility of the terminal in the IEEE 802.16d communication system, and the terminal having the mobility is called an MS (Mobile Station).

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

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 A base station 140 that manages the cell 150 and a plurality of MSs 111, 113, 130, 151, and 153. The signal transmission / reception between the BSs 110 and 140 and the MSs 111, 113, 130, 151 and 153 is performed using the OFDM / OFDMA scheme. The MS 130 of the MSs 111, 113, 130, 151 and 153 is located in a boundary region between the cell 100 and the cell 150, i.e., a handover region. Accordingly, when the MS 130 moves to the cell 150 that the BS 140 manages while transmitting and receiving signals with the BS 110, the serving BS transmits a signal to the BS 110 from the BS 110, (140).

In the general IEEE 802.16e communication system, a signaling transmission / reception is performed through a direct link between a fixed base station and an MS as shown in FIG. 1, so that a reliable wireless communication link between the base station and the MS can be easily established. However, since the IEEE 802.16e communication system has a fixed base station location, flexibility in the wireless network configuration is low, and thus it is difficult to provide an efficient communication service in a wireless environment where the traffic distribution and the call demand change are severe.

In order to overcome such a disadvantage, a multi-hop relay data transmission method using a fixed relay station or a mobile relay station or general MSs is applied to a general cellular wireless communication system such as the IEEE802.16e communication system . The wireless communication system using the multi-hop relay scheme can quickly reconfigure the network in response to a change in the communication environment, and can efficiently operate the entire wireless network. For example, the 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 BS and the MS is poor, a relay station is provided between the BS and the MS to configure a multi-hop relay path through the RS, thereby providing the MS with a better channel state. Further, by using the multi-hop relay scheme 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 coverage area of the base station 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 coverage area of a base station.

2, the multi-hop relay wireless communication system has a multi-cell structure, that is, a base station (BS) having a cell 200 and a cell 240 and managing the cell 200 A plurality of MSs 211 and 213 located in the cell 200 and a plurality of MSs 211 and 213 that are managed by the BS 210, Hop relay paths between a plurality of MSs 221 and 223 existing in an area 230 outside the area 230 and MSs 221 and 223 existing in the area 210 and the BS 210 A relay station 220 and a plurality of MSs 251, 253 and 255 located in an area of the cell 240 and an MS 270 located in an area 270 outside the cell 240 area managed by the BS 250 And a relay station 260 for providing a multi-hop relay path between the MSs 261 and 263 and the MSs 261 and 263 located in the BS 270 and the BS 250. [ The signal transmission and reception between the BSs 210 and 250 and the RSs 220 and 260 and the MSs 211, 213, 221, 223, 251, 253, 255, 261 and 263 are performed by the OFDM / OFDMA .

Next, a structure of a wireless communication system using a multi-hop relay scheme for increasing system capacity will be described.

3 is a diagram schematically illustrating a structure of a broadband wireless communication system using a multi-hop relay scheme for increasing system capacity.

3, the multi-hop relay wireless communication system includes a base station 310, a plurality of MSs 311, 313, 321, 323, 331 and 333, a BS 310 and MSs 311, 313, 321, 323, 331, and 333. The relay stations 320 and 330 provide a multi-hop relay path. Signals are exchanged between the BS 310 and the RSs 320 and 330 and the MSs 311, 313, 321, 323, 331 and 333 using the OFDM / OFDMA scheme. The BS 310 manages the cell 300 and the MSs 311, 313, 321, 323, 331 and 333 included in the cell 300 region and the RSs 320 and 330 communicate with the BS 300 310 and the signal can be directly transmitted and received.

When the MS 300 is located near the edge of the cell 300 as in the case of the partial MSs 321, 323, 331 and 333, the direct link between the BS 310 and the MSs 321, 323, 331, The signal-to-noise ratio (SNR) may be low. At this time, the RSs 320 and 330 provide a high-speed data transmission path to the MSs 321, 323, 331, and 333, thereby increasing the effective data rate of the MSs and increasing the system capacity.

In the broadband wireless communication system using the multi-hop relay shown in FIG. 2 or FIG. 3, the relay stations 220, 260, 320, and 330 are installed in the base stations 210, 250, May be an infrastructure relay station that is known and managed in advance, or may be a client relay station operating as a subscriber terminal (SS or MS) or a relay station depending on circumstances. The relay stations 220, 260, 320, and 330 may be fixed relay stations having no mobility, nomadic relay stations having nomadic characteristics (e.g., notebooks), mobile relay stations Lt; / RTI >

On the other hand, in the system using the multi-hop relay, the base station can perform communication with the relay station managed by the base station and communication between the relay station and the terminal. In this way, a case where a base station performs both a relay link in which a base station and a relay station communicate with each other and an access link in which a relay station and a terminal communicate are all referred to as centralized scheduling. Conversely, a case where a relay station directly schedules a terminal managed by the relay station without involvement of a base station is referred to as distributed scheduling.

However, in the case of performing the distributed scheduling, the relay station may desire to communicate with the terminal through dedicated resources. For example, if there is a large interference from a neighboring node with respect to communication with the terminal, the relay station may desire to communicate via dedicated resources available only to the relay station. In this case, the dedicated resource must be scheduled by the base station. That is, the RS must request a dedicated region that can be used only by the BS, and the BS determines an area corresponding to the area size requested by the RS, and informs the relay station of the determined area. That is, even when distributed scheduling is performed, it is necessary for the base station to perform scheduling for the access link (or access zone) in which the relay station and the terminal communicate with each other. In this case, the relay access resource a signaling procedure is required to allocate a region.

Accordingly, it is an object of the present invention to provide an apparatus and method for allocating a dedicated access area for communication with a terminal to a relay station that performs distributed scheduling in a wireless communication system using a multi-hop relay scheme.

It is another object of the present invention to provide an apparatus and method for informing a relay station that performs distributed scheduling in a wireless communication system using a multi-hop relay scheme.

It is still another object of the present invention to provide a signaling apparatus and method for allocating a dedicated access resource for communication with a terminal to a relay station that performs distributed scheduling in a multi-hop relay wireless communication system.

According to one aspect of the present invention, there is provided a method of a relay station communication method in a multi-hop relay wireless communication system, comprising: relaying communication between a base station and a terminal; The method includes the steps of: determining whether a dedicated resource for a dedicated access area is required; configuring a dedicated access area request message including necessary resource amount information when the dedicated resource is required; and transmitting the dedicated access area request message to the base station .

According to another aspect of the present invention, there is provided a communication method of a base station in a multi-hop relay wireless communication system, the method comprising: determining whether dedicated resource allocation is required for an access link in which a relay station and a terminal communicate; Determining a dedicated resource to be allocated to the relay station if necessary, configuring a dedicated access area allocation message including the determined dedicated resource information, and transmitting the dedicated access area allocation message to the relay station .

According to another aspect of the present invention, there is provided a relay station apparatus in a wireless communication system using a multi-hop relay scheme, the relay station apparatus comprising: a controller for controlling a relay service between a base station and a terminal, And a transmission unit for transmitting the dedicated access area request message to the base station. The base station includes a base station for transmitting the dedicated access area request message to the base station, and a dedicated access area request message for transmitting the dedicated access area request message to the base station.

According to another aspect of the present invention, in a base station apparatus in a multi-hop relay wireless communication system, it is determined whether dedicated resource allocation is required for an access link through which a relay station and a terminal communicate, A controller for determining a dedicated resource to be allocated to the relay station, a message generator for configuring a dedicated access area allocation message including the determined dedicated resource information, and a transmitter for transmitting the dedicated access area allocation message to the relay station .

According to another aspect of the present invention, there is provided a communication method of a base station in a multi-hop relay wireless communication system, the method comprising: receiving a dedicated access area request message from a relay station; Determining whether a dedicated access area can be allocated to the relay station, and if the dedicated access area can be allocated to the relay station, transmitting a dedicated access area allocation message including information on a dedicated resource allocated to the relay station to the relay station And transmitting a dedicated access area unassignment message to the relay station when the dedicated access area can not be allocated to the relay station.

As described above, the present invention can allocate a dedicated access resource for communication with a terminal to a relay station performing distributed scheduling. In this manner, when the dedicated resource is allocated, the relay station can communicate with the terminal through the dedicated resource without interfering with other nodes, so that the communication quality with the terminal can be improved.

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, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention and may vary depending on the intention of the user, the operator, or the like. Therefore, the definition should be based on the contents throughout this specification.

The present invention provides a signaling procedure for allocating a dedicated resource to an access zone (or an access link) between a relay station and a terminal when performing distributed scheduling in a broadband wireless communication system using a multi-hop relay scheme I suggest.

The relay station transmits the capability information required for dedicated communication with the mobile station in the downlink or uplink to the base station. The base station determines a dedicated region to be used by the relay station based on the capability information, To the relay station and the neighboring relay station. Then, the RS performs scheduling for the dedicated area to provide a relay service to the MS, and the neighboring RS excludes the dedicated area from the scheduling.

For example, a broadband wireless communication system using the multi-hop relay scheme is a communication system using an OFDM / OFDMA scheme and transmits a physical channel signal using a plurality of sub- And can support the mobility of the MS through a multi-cell structure.

Hereinafter, the present invention will be described by taking a broadband wireless access communication system as an example. However, the present invention can be similarly applied to a cellular-based communication system using a multi-hop relay scheme.

FIG. 4 illustrates an operation procedure of a base station in a wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention.

Referring to FIG. 4, in step 401, the BS transmits and receives data to and from the MS through the relay service of the RS. In step 403, the BS checks whether a dedicated access zone request message is received from the RS during communication with the MS using the relay service. The RS transmits the dedicated access area request message to the BS when it wants to communicate with the MS through the dedicated resource. An example of the dedicated access request message is shown in Table 1 below.

Syntax Notes RS Dedicated Access Zone Request {  HT Indicate header Type  EC Indicate encryption control  Type Indicate extended MAC signaling header type II  Extended Type Indicate RS dedicated access zone request header  DL / UL Indicator Indicate the request for a DL access zone or a UL access zone  BR Number of OFDMA slots requested for the RS portion of the DL (or UL) access zone  CID Basic CID (or tunnel CID) of the RS  HCS header check sequence }

As shown in Table 1, the Dedicated Access Zone Request message includes an HT (Header Type), an EC (Encryption Control), a Type, an Extended Type, a DL / UL indicator (DL / UL indicator), a bandwidth request, a CID (Connection Identifier), and a HCS (Header Check Sequence). That is, the dedicated access area request message includes an indicator indicating whether the dedicated access area to be requested is the uplink or the downlink, the capability information requested by the relay station, and the identifier information of the relay station.

The structure of Table 1 can be used when requesting a dedicated region for one of the uplink and the downlink, but it is difficult to use the dedicated region when requesting a dedicated region for both the uplink and the downlink. Accordingly, the dedicated access area request message may be implemented as another example as shown in Table 2 below.

Syntax Notes RS Dedicated Access Zone Request {  HT Indicate header Type  EC Indicate encryption control  Type Indicate extended MAC signaling header type II  Extended Type Indicate RS dedicated access zone request header  DL Indicator Indicate the request of DL access zone  DL BR Number of OFDMA slots requested for the RS portion of the DL access zone  UL Indicator Indicate the request of UL access zone  UL BR Number of OFDMA slots requested for the RS portion of the UL access zone  CID Basic CID (or tunnel CID) of the RS  HCS header check sequence }

As shown in Table 2, the dedicated access area request message includes an indicator (DL indicator) indicating that the dedicated resource requested by the relay station is a downlink, large capacity information (DL BR) requesting the downlink, (UL Indicator) indicating that the dedicated resource requested by the relay station is the uplink, large capacity information (UL BR) requesting the uplink, and identifier (CID) information of the relay station. If a dedicated resource is requested for one of the downlink and the uplink, the bandwidth for the link that does not need to be allocated may be set to '0'.

In addition, the dedicated access area request message may be implemented as an RS UL size request header defined in the current standard as another example.

Syntax Notes RS UL size request header format () {  HT set to 1  EC set to 1  Type set to 1  Extended Type set to 5
indication RS UL size request header  you Number of OFDMA slots requested for the RS portion of the UL access zone  CID Basic CID of the RS  HCS header check sequence }

As shown in Table 3, the dedicated access area request message includes the capability information requesting the uplink and the relay station identifier information. However, since the message of Table 3 can request a resource only for an uplink, Table 1 or Table 2 can be used to request a resource for a downlink.

The above tables 1 to 3 are constructed using an extended type structure of "extended MAC signaling header type II " of IEEE 802.16j, for example, and the dedicated access area request message is not a header And may be configured in the form of a general message (MAC management).

When the dedicated access area request message is received from the relay station, the base station determines a dedicated access area to be allocated to the relay station by referring to the in-message bandwidth information in step 405. In step 407, the BS transmits a message including allocation information of the determined dedicated access area. At this time, the dedicated access area assignment message may be transmitted in a broadcast manner so that neighboring RSs can also receive the dedicated access area allocation message. The dedicated access area allocation message may be configured as shown in Table 4 below.

Syntax Notes RS Dedicated Access Zone Alloc {  Type RS dedicated access zone allocation IE  Length  RS CID Basic CID of RS which request the allocation of dedicated access zone  DL / UL indicator Indication the request is for DL access zone or UL access zone  OFDMA symbol offset  Subchannel offset  No. OFDMA symbols  No. subchannels }

As shown in Table 4, the dedicated access area assignment message includes an identifier (RS CID) of a relay station, an indicator (DL / UL indicator) indicating whether a dedicated dedicated access area is an uplink or a downlink, (OFDMA symbol offset, sub-channel offset, No. OFDMA stymbols, No. sub-channels, duration) for the dedicated access area.

If the dedicated access area request message received in step 403 is an RS UL size request header as shown in Table 3, the BS transmits an allocation message To the relay station.

Syntax Notes RS Dedicated UL Access Zone Alloc {  Type RS dedicated access zone allocation IE  Length  RS CID Basic CID of RS which request the allocation of dedicated access zone  OFDMA symbol offset  Subchannel offset  No. OFDMA symbols  No. subchannels }

As shown in Table 5, the dedicated access area assignment message includes RS CID information and resource information (OFDMA symbol offset, Subchannel offset, No. OFDMA stymbols, No. subchannels , duration).

The resource information for the dedicated access area included in the dedicated access area allocation message of Table 4 and Table 5 is represented by the OFDMA symbol offset of the access area and the duration information of the allocated access area, (OFDMA symbol offset), symbol number (No.OFDMA symbols) of the area, or OFDMA symbol offset, subchannel offset, No.OFDMA symbols of the access area, The number of subchannels (No. subchannel).

The dedicated access area allocation message of Table 4 and Table 5 may further include time information for activating use of the allocated dedicated area. In addition, the BS can continuously allocate the dedicated region allocated through the dedicated access area allocation message to the RS for a predetermined period. In this case, the dedicated access area allocation message may further include allocation period information. The allocation period information may indicate how many frames the dedicated area is allocated for each frame. As another method for allocating the dedicated access area for a predetermined period in the relay station, an indicator indicating assignment or release may be included in the dedicated access area allocation message. That is, after the dedicated access area is allocated to the relay station, the assignment message including the release indicator is transmitted to release the dedicated access area.

The dedicated access area assignment messages of Table 4 and Table 5 are used for a relay area map (R-MAP) message transmitted from a base station to a relay station, a Relay Station-Channel Descriptor (RS-CD) message transmitted to a relay station It can be transmitted in the form of a general broadcast message or a multicast message.

FIG. 5 illustrates an operation procedure of a relay station in a wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention.

Referring to FIG. 5, in step 501, the RS relays communication between the BS and the MS. During the provision of the relay service to the MS, the RS determines in step 503 whether a dedicated access area for providing the relay service to the MS is necessary. For example, when interference received from a neighboring relay station exceeds a certain threshold value and affects communications between the relay station and the terminal, the relay station may determine that a dedicated area is necessary. The threshold value may be managed in the base station or the relay station. The base station or the relay station compares the threshold value with a signal measurement value (e.g., CINR (Carrier to Interference and Noise Ratio), SINR (Signal to Interference and Noise Ratio), RSSI (Received Signal Strength Indicator) And judges the degree of interference. If it is determined that the interference is equal to or higher than the appropriate level, a dedicated access area can be allocated to the terminal.

If it is determined that the dedicated access area is required, the RS transmits a dedicated access area request message to the BS in step 505. At this time, the RS can transmit a message as shown in Table 1, Table 2, or Table 3 above.

In step 507, the RS receives a dedicated access area allocation message from the BS. Here, the dedicated access area allocation message may have a structure as shown in Table 4 or Table 5. [ If the dedicated access area allocation message is received, the RS proceeds to step 509 and interprets the dedicated access area allocation message and determines whether the allocation information in the dedicated access area allocation message is its own. That is, it is determined whether the relay station identifier set in the dedicated access area allocation message is its own identifier.

If the relay station identifier set in the dedicated access area allocation message is its own identifier, the RS proceeds to step 511 and performs resource scheduling for the dedicated access area designated by the dedicated access area allocation message, To the terminal.

On the other hand, if the RS identifier set in the dedicated access area allocation message is not an identifier of the RS, the RS proceeds to step 513 and recognizes that the dedicated access area designated by the dedicated access area allocation message is dedicated to another RS , And excludes the dedicated access area from the scheduling. At this time, the RS may broadcast a zone switch IE indicating the existence of a new zone so that the UE can recognize the dedicated access area.

The above embodiment of the present invention is a case where a dedicated access area is allocated by transmitting a dedicated access area request message to a base station in a relay station and transmitting a dedicated access area allocation message to a relay station in a base station. However, it is possible to determine whether or not the dedicated access area is allocated by the base station determination without requesting the relay station. At this time, if allocation of the dedicated access area is required, the base station can construct a message as shown in Table 4 or Table 5 and transmit it to the relay station. Here, the necessity of allocation of the dedicated access area can be determined by using the amount of interference the terminal experiences during communication with the relay station. In addition, a dedicated access area can be allocated for a user with a high rating that pays a large fee, and thus the allocation criterion of the dedicated access area can be variously implemented.

4 and 5, a scenario is described in which a dedicated access area is allocated to a relay station that has requested a dedicated access area allocation. Next, when a dedicated access area can not be allocated to a relay station that requested the dedicated area allocation, A scenario for transmitting a dedicated access area unassignable message will be described.

6 illustrates an operation procedure of a base station in a wireless communication system using a multi-hop relay scheme according to another embodiment of the present invention.

Referring to FIG. 6, in step 601, the BS transmits and receives data to and from the MS through the relay service of the RS. In step 603, the BS checks whether a dedicated access zone request message is received from the RS during communication with the MS using the relay service. The dedicated access area request message may have the structure of Table 1, Table 2, or Table 3 above.

When receiving the dedicated access area request message from the RS, the BS determines in step 605 whether the dedicated access area can be allocated to the RS by referring to the capability information in the dedicated access area request message. If the dedicated access area can be allocated to the RS, the BS proceeds to step 607 to determine a dedicated access area to be allocated to the RS. In step 609, the BS transmits a message including allocation information of the determined dedicated access area to the RS Lt; / RTI > At this time, the dedicated access area assignment message can be transmitted in a broadcast manner so that the neighboring base station can also receive the dedicated access area allocation message. Also, the dedicated access area allocation message may have the structure of Table 4 or Table 5, and includes an indicator for indicating allocation of a dedicated access area and area information allocated to the relay station.

On the other hand, if it is determined in step 605 that the dedicated access area can not be allocated to the RS, the BS proceeds to step 611 and transmits a message indicating that the dedicated access area can not be allocated to the RS. The dedicated access area unassignable message may be a message of Table 4 or Table 5 including an indication indicating that allocation of the dedicated area is not possible or an allocation of the dedicated area is unavailable. For example, by setting an indicator indicating the cancellation of the dedicated access area in the message of Table 4 or Table 5 and setting the corresponding fields indicating the dedicated access area to a value of '0', a dedicated access area unassignable message is executed can do.

FIG. 7 illustrates an operation procedure of a relay station in a wireless communication system using a multi-hop relay scheme according to another embodiment of the present invention.

Referring to FIG. 7, in step 701, the RS relays communication between the BS and the MS. During the provision of the relay service to the MS, the RS determines in step 703 whether a dedicated access area for providing the relay service to the MS is necessary. For example, if the interference received from the neighboring node exceeds a certain threshold and affects the communication between the relay station and the terminal, the relay station may determine that the dedicated area is necessary.

If it is determined that the dedicated access area is required, the RS transmits a dedicated access area request message to the BS in step 705. At this time, the RS can transmit a message as shown in Table 1, Table 2, or Table 3 above.

In step 707, the RS receives a message from the BS in response to the dedicated access area request message. In step 709, the RS analyzes the received message and determines whether the received message is a dedicated access area allocation message. Herein, the dedicated access area allocation message has a structure as shown in Table 4 or Table 5, and includes an indicator indicating allocation of a dedicated access area and information on a dedicated dedicated access area. If the dedicated access area allocation message is received, the RS proceeds to step 711 and performs resource scheduling for the dedicated access area designated by the dedicated access area allocation message, and communicates with the terminal through the dedicated access area .

On the other hand, if it is determined in step 709 that a dedicated access area allocation unavailable message is received, the RS proceeds to step 713 and communicates with the terminal through an arbitrary access area other than the dedicated access area. The dedicated access area unassignable message may be a separate message indicating that the dedicated access area is unassignable or may be the message of Table 4 or Table 5 including an indicator indicating that the dedicated area is unassignable.

8 shows a block configuration of a base station (or relay station) according to an embodiment of the present invention. Here, since the base station and the relay station having the same interface module (communication module) have the same block configuration, the operation of the base station and the relay station will be described below with reference to FIG. Hereinafter, a description will be given assuming a TDD-OFDMA system. However, the present invention can be easily applied to an FDD-OFDMA system, a hybrid system using TDD and FDD together, and a cellular-based system using another resource partitioning scheme.

As shown, the base station (or relay station) according to the present invention includes an RF (Radio Frequency) receiver 801, an ADC (Analog to Digital Converter) 803, an OFDM demodulator 805, a decoder 807, A controller 811, a message generator 813, an encoder 815, an OFDM modulator 817, a digital to analog converter (DAC) 819, an RF transmitter 821, and a duplexer 823 .

8, the duplexer 823 first transmits a transmission signal from the RF transmitter 821 through an antenna according to a duplexing scheme, and provides a reception signal from the antenna to the RF receiver 801. FIG. For example, in the case of a TDD (Time Division Duplex) scheme, the duplexer 823 transmits a signal from the RF transmitter 821 through an antenna in a transmission interval, Signal to the RF receiver (801).

The RF receiver 801 converts an RF (Radio Frequency) signal received through an antenna into a baseband analog signal. The ADC 803 converts the analog signal from the RF receiver 801 into sample data and outputs it. The OFDM demodulator 805 performs Fast Fourier Transform (FFT) on the sample data from the ADC 803 to convert the data into frequency domain data, and selects and outputs data of subcarriers to be actually received in the frequency domain data.

The decoder 807 demodulates and decodes the data from the OFDM demodulator 805 according to a predetermined modulation level (modulation and coding scheme (MCS) level) and outputs the demodulated and decoded data.

The message processor 809 analyzes the control message from the decoder 807 and provides the result to the controller 811. The control unit 811 processes the information from the message processing unit 809, generates information to be transmitted, and provides the generated information to the message generating unit 813. Here, it is assumed that the controller 811 performs resource scheduling. The message generator 813 generates a message with various kinds of information provided from the controller 811 and outputs the message to the encoder 815 of the physical layer.

The encoder 815 codes and modulates the data from the message generator 813 according to a predetermined modulation level (MCS level). The OFDM modulator 817 performs IFFT (inverse fast Fourier transform) on the data from the encoder 815 and outputs sample data (OFDM symbol). The DAC 819 converts the sample data into an analog signal and outputs the analog signal. The RF transmitter 821 converts an analog signal from the DAC 819 into an RF (Radio Frequency) signal and transmits the signal through an antenna.

In the above-described configuration, the control unit 811 controls the message processing unit 809 and the message generation unit 813 as a protocol control unit. That is, the controller 811 may perform the functions of the message processor 809 and the message generator 813. In the present invention, these are separately configured to distinguish the respective functions. Accordingly, in the case of actual implementation, all of them can be processed by the control unit 811, and only a part of them can be processed by the control unit 811.

In addition, the controller 811 receives information necessary for performing the protocol processing to the corresponding component of the physical layer or generates a control signal to the corresponding component of the physical layer.

Hereinafter, operations of the BS and the RS according to the present invention will be described with reference to FIG. Hereinafter, the signaling process performed in the MAC (Media Access Control) layer will be described.

First, the operation of the base station will be described.

The message processing unit 809 analyzes the dedicated access area request message received from the relay station and provides the control unit 811 with various information extracted from the dedicated access area request message. Here, the dedicated access area request message may be the message of Table 1, Table 2, or Table 3, for example.

The controller 811 determines whether a dedicated access area can be allocated to the relay station using the information of the dedicated access area request message from the message processor 809. [ At this time, if the dedicated access area can be allocated to the relay station, the dedicated access area to be allocated to the relay station is determined, and information on the determined dedicated access area is transmitted to the message generator 813. On the other hand, if the dedicated access area can not be allocated, the controller 811 instructs the message generator 813 to generate a dedicated access area allocation disable message.

In this way, the base station can allocate the dedicated access area to the relay station by the request of the relay station, or can allocate the dedicated access area to the relay station by the determination of the base station without request of the relay station. In the case of allocation by the base station judgment, the base station can determine whether to allocate the dedicated access area by using signal measurement values (e.g., CINR, SINR, RSSI, interference level, etc.) reported from the terminal.

The message generator 813 constructs a dedicated access area allocation message or a dedicated access area allocation disable message using the information from the controller 811 and transmits the message to the physical layer. Herein, the dedicated access area allocation message may be a message as shown in Table 4 or a message as shown in Table 5, for example, and may include information indicating the allocation of the dedicated access area and the allocated dedicated access area. Also, the dedicated access area allocation unassigned message may be the message of Table 4 or Table 5, which includes a separate message indicating unallocation or an unallocable indicator.

Meanwhile, the message generated by the message generator 813 is processed in a form that can be transmitted by the physical layer, and then transmitted to the RS. At this time, the dedicated access area allocation message may be transmitted in the form of a relay area map (R-MAP) message, a relay system configuration (RS-CD) message, or a general broadcast message or multicast message.

Next, the operation of the relay station will be described.

The control unit 811 determines whether a dedicated access area for providing a relay service to the terminal is necessary. For example, the controller 811 can determine the necessity of a dedicated access area by examining a signal measurement value (e.g., CINR, SINR, RSSI, interference level, etc.) reported from the terminal and a user class of the terminal. If it is determined that the dedicated access area is required, the controller 811 provides the message generator 813 with information necessary for generating a dedicated access area request message.

Then, the message generator 813 constructs a dedicated access area request message using the information from the controller 811, and transmits the request message to the physical layer. Here, the dedicated access area request message may be a message of Table 1, a message of Table 2, or a message of Table 3, for example. Meanwhile, the message generated by the message generator 813 is processed in a form that can be transmitted by the physical layer, and then transmitted to the base station.

Meanwhile, a dedicated access area allocation message or a dedicated access area allocation disabled message may be received from the base station in response to the dedicated access area request message. Also, the dedicated access area allocation message may be received by the base station itself.

Upon receiving the dedicated access area allocation message from the base station, the message processor 809 analyzes the dedicated access area allocation message and provides the controller 811 with various information extracted from the dedicated access area allocation message. Here, it is assumed that the dedicated access area assignment message is a broadcast message or a multicast message received by a plurality of relay stations.

Then, the controller 811 analyzes the information from the message processor 809 and determines whether a dedicated access area is allocated to the relay station. If the dedicated access area is allocated to the RS, the controller 811 performs resource scheduling for the allocated dedicated access area and provides a relay service to the corresponding terminal through the dedicated access area. On the other hand, if the area designated by the allocation message is allocated to another RS, the controller 811 excludes the dedicated access area allocated to the other RS from the scheduling.

If a dedicated access area allocation unavailable message is received from the base station, the controller 811 performs resource scheduling for an arbitrary access area other than the dedicated access area, and provides a relay service to the terminal according to the scheduling result do.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited by the illustrated embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

1 schematically shows a structure of a general IEEE 802.16e communication system;

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.

3 is a diagram schematically illustrating a structure of a broadband wireless communication system using a multi-hop relay scheme for increasing system capacity.

4 is a flowchart illustrating an operation procedure of a base station in a wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention.

5 is a flowchart illustrating an operation procedure of a relay station in a wireless communication system using a multi-hop relay scheme according to an embodiment of the present invention.

6 is a flowchart illustrating an operation procedure of a base station in a wireless communication system using a multi-hop relay scheme according to another embodiment of the present invention.

7 is a diagram illustrating an operation procedure of a relay station in a wireless communication system using a multi-hop relay scheme according to another embodiment of the present invention.

8 is a block diagram of a base station (or relay station) according to an embodiment of the present invention;

Claims (31)

A communication method of a relay station in a wireless communication system using a multi-hop relay scheme, Comprising the steps of: relaying communication between a base station and a terminal; Determining whether a dedicated resource is required for communication with the terminal; Configuring a dedicated access area request message including necessary resource amount information when the dedicated resource is required; And transmitting the dedicated access area request message to the base station, Wherein the determining step determines whether the dedicated resource is required by comparing an interference amount affecting communication with the terminal with a threshold value. The method according to claim 1, The dedicated access area request message includes an indicator indicating that the requested dedicated resource is a downlink, a capability information requested for a downlink, an indicator indicating that a requested dedicated resource is an uplink, a capability information requested for an uplink, A relay station identifier, and a relay station identifier. delete The method of claim 1, And comparing at least one of CINR, SINR, RSSI and interference level reported from the terminal with a threshold value. The method according to claim 1, Further comprising the step of receiving a dedicated access area allocation message from the base station. 6. The method of claim 5, Analyzing the received dedicated access area assignment message; Determining whether a dedicated resource designated by the allocation message is allocated to the relay station; Further comprising the step of performing scheduling for the dedicated resource when the RS is allocated to the RS. The method according to claim 6, Further comprising the step of excluding the dedicated resource from scheduling when the dedicated resource is allocated to another relay station. 6. The method of claim 5, The dedicated access area assignment message includes an indicator indicating that the dedicated resource to be allocated is an uplink, dedicated resource information allocated to the uplink, a support resource indicating that the allocated dedicated resource is a downlink, dedicated resource information allocated to the downlink , Start time information in which allocated dedicated resources are activated, and duration information in which allocated dedicated resources are valid. 9. The method of claim 8, The dedicated access area allocation message includes at least one of a relay area map message, a Relay Station-Channel Descriptor (RS-CD) message sent to a relay station, a separately defined broadcast message, a separately defined multicast message ≪ / RTI > The method according to claim 1, Analyzing a message received from the base station after transmitting the dedicated access request message; Providing a relay service to a terminal using the dedicated access area when the received message is a dedicated access area allocation message; Further comprising the step of recognizing that the dedicated access area is unassignable when the received message is a dedicated access area unallocated message. The method according to claim 1, Further comprising the step of scheduling relay communication between the base station and the terminal. A communication method of a base station in a wireless communication system using a multi-hop relay scheme, Determining whether dedicated resource allocation is required for an access link through which the relay station and the terminal communicate; Determining a resource to be allocated to the RS if the dedicated resource is required; Configuring a dedicated access area allocation message including the determined dedicated resource information, And transmitting the dedicated access area assignment message to the relay station, Wherein the determining step determines whether allocation of the dedicated resource is necessary by comparing an interference amount affecting communication with the terminal with a threshold value. 13. The method of claim 12, The dedicated access area assignment message includes an indicator indicating that the dedicated resource to be allocated is an uplink, dedicated resource information allocated to the uplink, an indicator indicating that the allocated dedicated resource is a downlink, dedicated resource information allocated to the downlink, A start time information in which an allocated dedicated resource is activated, and a duration information in which an allocated dedicated resource is valid. delete 13. The method of claim 12, And comparing at least one of CINR, SINR, RSSI and interference level reported from the terminal with a threshold value. 13. The method of claim 12, Further comprising the step of receiving a dedicated access area request message requesting the dedicated resource from the relay station. 17. The method of claim 16, Further comprising the step of transmitting a dedicated access area unallocated message to the relay station when the dedicated access area can not be allocated to the relay station. 17. The method of claim 16, The dedicated access area request message includes an indicator indicating that the requested dedicated resource is a downlink, a capability information requested for a downlink, an indicator indicating that a requested dedicated resource is an uplink, a capability information requested for an uplink, A relay station identifier, and a relay station identifier. 19. The method of claim 18, The dedicated access area allocation message includes at least one of a relay area map message, a Relay Station-Channel Descriptor (RS-CD) message sent to a relay station, a separately defined broadcast message, a separately defined multicast message ≪ / RTI > 1. A relay station apparatus in a wireless communication system using a multi-hop relay scheme, A controller for controlling a relay service between the base station and the terminal and determining whether dedicated resources are required for communication with the terminal; A message generator for configuring a dedicated access area request message including necessary resource amount information when the dedicated resource is required; And a transmitter for transmitting the dedicated access area request message to the base station, Wherein the control unit compares the interference amount affecting communication with the terminal with a threshold value to determine whether the dedicated resource is needed. 21. The method of claim 20, The dedicated access area request message includes an indicator indicating that the requested dedicated resource is a downlink, a capability information requested for a downlink, an indicator indicating that a requested dedicated resource is an uplink, a capability information requested for an uplink, A relay station identifier, and a relay station identifier. 21. The method of claim 20, Further comprising: a receiving unit for receiving a dedicated access area allocation message from the base station. 23. The method of claim 22, The dedicated access area assignment message includes an indicator indicating that the dedicated resource to be allocated is an uplink, dedicated resource information allocated to the uplink, an indicator indicating that the allocated dedicated resource is a downlink, dedicated resource information allocated to the downlink, A start time information in which an allocated dedicated resource is activated, and a duration information in which an allocated dedicated resource is valid. 23. The apparatus of claim 22, Wherein the scheduling unit analyzes the received dedicated access area assignment message, determines whether a dedicated resource specified by the assignment message is allocated to the relay station, and performs scheduling for the dedicated resource when allocated to the relay station . 25. The apparatus of claim 24, And excludes the dedicated resource from the scheduling if the dedicated resource is allocated to another relay station. 21. The method of claim 20, Further comprising a message processor for analyzing a message received from the base station after transmitting the dedicated access request message, Wherein the control unit recognizes that the dedicated access area can not be allocated if the received message is a dedicated access area unallocated message. A base station apparatus in a wireless communication system using a multi-hop relay scheme, A controller for determining whether a dedicated resource is allocated to an access link through which a relay station and a terminal communicate with each other and determining a dedicated resource to be allocated to the relay station when the dedicated resource is required; A message generator for configuring a dedicated access area allocation message including the determined dedicated resource information, And a transmitter for transmitting the dedicated access area allocation message to the relay station, Wherein the control unit compares the interference amount affecting communication with the terminal with a threshold value to determine whether allocation of the dedicated resource is necessary. 28. The method of claim 27, Further comprising: a receiving unit for receiving a dedicated access area request message requesting the dedicated resource from the relay station. 29. The apparatus of claim 28, wherein the message generator comprises: And generates a dedicated access area allocation unavailable message when the dedicated access area can not be allocated to the relay station. 29. The method of claim 28, The dedicated access area request message includes an indicator indicating that the requested dedicated resource is a downlink, a capability information requested for a downlink, an indicator indicating that a requested dedicated resource is an uplink, a capability information requested for an uplink, A relay station identifier, and a relay station identifier. 28. The method of claim 27, The dedicated access area assignment message includes an indicator indicating that the dedicated resource to be allocated is an uplink, dedicated resource information allocated to the uplink, an indicator indicating that the allocated dedicated resource is a downlink, dedicated resource information allocated to the downlink, A start time information in which an allocated dedicated resource is activated, and a time information in which an allocated dedicated resource is valid.

Images