KR100891118B1 - Frame structure for MMR system and communication method using the same - Google Patents

Abstract

The present invention relates to a frame structure for a mobile multi-hop relay (MMR) system and a communication method using the frame, wherein a new node RS can be added without modification to an existing MS, and a single hop of an existing standard. In addition to transmitting to nodes, it can also transmit to multihop nodes, minimizing modifications to the BS.

Description

Frame structure for MMR system and communication method using the frame {Frame structure for MMR system and communication method using the same}

1 illustrates a frame structure of an IEEE 802.16 system.

2 is a diagram illustrating an example of a network of an MMR system to which the present invention is applied.

3 is a view showing a frame structure for an MMR system according to the present invention.

4 is a flowchart showing a process of a communication method according to the present invention.

5 is a flowchart illustrating a frame generation process of FIG. 4 in more detail.

6 is a block diagram showing the configuration of a relay station according to the present invention.

7 is a diagram illustrating a process of processing a direct region of a frame according to the present invention at a relay station.

8 is a diagram illustrating a process of processing a relay region of a frame in a relay station according to the present invention.

The present invention relates to a frame structure suitable for a mobile multi-hop relay (MMR) system and a communication method using the frame, and more specifically, to an existing standard (IEEE Std. 802.16-2004) supporting only a single hop. And a frame structure, a communication method, and an apparatus for supporting multi-hop by improving the frame structure of IEEE Std. 802.16e-2005.

The frame structure of the existing standard is the same as that of FIG. 1 and is designed considering only a single hop such as BS-MS2 205 and BS-MS4 206 of FIG.

The base station (hereinafter referred to as "BS") of the existing standard provides each terminal with a comprehensive consideration of information such as resource requirements of the mobile station (hereinafter referred to as " MS " ) and anticipated MS resource usage. Determine the amount of resources allocated. Based on the determined resource amount, a frame having the form as shown in FIG. 1 is configured, and the configuration information of the frame is stored in the MAP, and then the entire frame is broadcast. Upon receiving the broadcast frame, the MS checks the MAP information and identifies the location of the resource allocated to the MS. If the allocated resource exists on the downlink, the burst is received through the corresponding area. If the allocated resource exists on the downlink, the burst is transmitted through the corresponding area. If present in both downlink and uplink, both transmission and reception are performed.

 Since the frame structure of the existing standard is designed without considering the relay station (relay station, hereinafter referred to as “RS”), it can be used only when the distance between the BS and the MS is single hop. Therefore, the frame structure of the existing standard could not support a multi-hop environment such as a path leading to BS-RS2-RS3-MS5 of FIG. 2.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a frame structure and a communication method using the frame structure to support a multi-hop environment by adding an RS under the constraint of not modifying an existing MS. To provide.

According to the present invention, a recording medium recording a frame structure for a mobile multi-hop relay (MMR) system includes: a first region including a preamble and a MAP to achieve the above technical problem; A second area allocated for a burst delivered to a mobile station or relay station at a single hop distance from the base station; A third area allocated for a burst delivered to a mobile station or a relay station at least two hops away from the base station; a downlink area comprising; and an uplink area including a burst delivered to the base station from the mobile station or relay station; It is characterized by including.

A communication method using a frame for an MMR (Mobile Multi-hop Relay) system according to the present invention comprises a base station, a mobile terminal, and an MMR system comprising a relay station connecting the base station and the mobile terminal, wherein the base station is connected to the mobile terminal. Generating and outputting a frame having a different area in which a burst delivered to the mobile terminal is carried according to the number of hops; And determining, by the relay station, whether the relay is simple for each region of the frame after receiving the frame. And as a result of the determination, the relay station amplifies the burst in the simple relay region and transmits the burst to the lower node, and transmits the burst in the region for the multi-hop mobile terminal to the lower node after performing a predetermined process. It is characterized by including.

The relay station using the frame for the MMR (Mobile Multi-hop Relay) system according to the present invention analyzes the received frame and simply amplifies each region within the frame to determine whether to deliver to a lower node or after processing. ; An amplifying unit for amplifying and outputting the signal strength with respect to the in-frame region determined by the determination unit to simply amplify; And a processor which performs a predetermined process on the in-frame area determined to be processed by the determination unit and outputs the result in the next frame. A relay station in the MMR system, comprising: outputting a frame to the determination unit and outputting an output signal of the amplifying unit and the processing unit to a lower node ; Characterized in that it comprises a.

Communication apparatus using a frame for a mobile multi-hop relay (MMR) system according to the present invention includes a mobile terminal; A base station for generating and outputting a frame capable of delivering a burst by dividing a downlink region according to the number of hops away from the base station by the mobile station; And a relay station for receiving the frame and simply amplifying and outputting the frame or outputting the predetermined frame after performing a predetermined process.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 2 is a diagram illustrating an example of a network of an MMR system to which the present invention is applied, and FIG. 3 is a diagram illustrating a frame structure for an MMR system according to the present invention. 4 is a flowchart illustrating a process of a communication method according to the present invention, and FIG. 5 is a flowchart illustrating the frame generation process of FIG. 4 in more detail. 6 is a block diagram showing the configuration of a relay station according to the present invention. 7 is a diagram illustrating a process of processing a direct region of a frame according to the present invention at a relay station, and FIG. 8 is a diagram illustrating a process of processing a relay region of a frame according to the present invention at a relay station.

First, the terms are defined.

BS: Base Station. Base station.

MS: Mobile Station. Terminal station.

RS: Relay Station. Relay station.

Downlink: Area in which data is transmitted from BS to another UE.

Uplink: An area in which data is transmitted from another terminal to a BS.

Burst: A collection of logical data.

Node: A component of a network. In the present document, we refer to BS, RS and MS.

Hop: The logical distance between nodes. The distance from one node to a logically adjacent node is 1-hop.

Single hop: The distance between BS and last node is 1

Multihop: The distance is more than 2 because there is another node between BS and last node.

MAP: Information about the composition of the current frame.

The frame structure of the present invention is shown in FIG.

The direct region 301 of FIG. 3 is a region containing control information such as preamble, FCH, MAP, etc., and includes information on the configuration state of the current frame, and is allocated in the same manner as the allocation method of the existing standard. This region is delivered directly through simple amplification at the RS.

The 1-hop region 302 of FIG. 3 is an area containing bursts transmitted to a node at a single hop distance from the BS and is allocated in the same manner as the downlink of the existing standard. That is, the bursts transmitted to MS2 205, MS4 206, RS1 202, and RS2 203 in BS 201 of FIG. 2, respectively, are transmitted through this region.

The multi-hop region 303 of FIG. 3 is an area including bursts transmitted to nodes at least two hops from the BS, and is a region newly defined in the present invention. That is, bursts delivered to MS1 207, MS3 208, MS5 209, and RS3 204 in the BS of FIG. 2 are transmitted through this region. This area is retransmitted and transmitted after a predetermined process (described below) in the RS where the transmitted signals are relayed.

The uplink of FIG. 3 is allocated in the same manner as the uplink of the existing standard, but unlike the existing standard, bursts transmitted from the multihop node to the BS also pass through this area. Bursts transmitted from multi-hop nodes are processed after RS processing.

The operation of the present invention will be described in more detail.

1. Frame composition method

The operation sequence of the present invention is as shown in FIG. First, the base station generates and outputs a frame as shown in FIG. 3 having a different area in which a burst delivered to the mobile terminal is carried according to the number of hops to the mobile terminal (step S410). After receiving the frame, the RS determines whether it is a simple relay for each region of the frame based on MAP information (steps S420 to S430). If the RS is a simple relay region, the RS amplifies the burst in the simple relay region and then lower nodes. In step S440, the burst in the area for the multi-hop mobile terminal performs a predetermined process (described below) and is then delivered to the next node in the next frame (step S450).

Referring to FIG. 5, the process of generating the frame of FIG. 3 (S410) will be described. The process of Figure 5 shows the process of forming a frame. First, the BS determines whether a pre-defined MAP exists in a previous frame (step S510), that is, it determines whether the information on the current frame has information on the MAP defined at the time of the last frame, and does not exist. In this case, all regions other than the direct region of the downlink are designated as 1-hop regions (step S515). If a predefined MAP exists, a portion of the downlink is designated as the multi-hop region, and the direct region and the multi-areas are designated. An area other than the hop region is designated as a 1-hop region (step S520).

Next, it is determined whether the allocation of the nodes accessing the BS has been completed. If the allocation is completed, all the frames currently being generated are finished. Therefore, the process ends and the process proceeds to the generation of the next frame. Unassigned In this case, the frame generation process continues. That is, it is determined whether the MS receives the burst in the frame currently being generated (S535) . The MS connected by 1-hop may determine that it receives a burst in the frame currently being generated, and the MS connected by multi-hop receives a burst in the currently generating frame according to the remaining hops (if the remaining hops are 1). In this case, it can be determined whether a frame is received in the next frame (when the remaining hop number is n, it can be determined to be received in the nth frame after the frame being generated).

If it is determined that the reception is not received in the next frame, the burst transmitted to the MS is allocated to the multi-hop region of the next frame (step S540).

However, as a result of the determination in step S535, when the MS receives a burst in the next frame, it is determined whether the MS is a multi-hop MS (step S545). As a result of the determination, if the multi-hop MS is assigned, the burst transmitted to the MS is allocated to the multi-hop region of the next frame, and the process proceeds to step S525 (step S560). On the other hand, if it is determined that the multi-hop MS is not assigned to the burst to be delivered to the MS 1-step transition to step S525 (S550).

That is, in the case of downlink, I) if the distance between the MS and the BS is single hop, the resource for the MS is allocated to the 1-hop region. II) In the case where the distance of the BS-MS is multi-hop, ① ① Resource allocation for the RS located in the single-hop distance of the BS between the BS-MS in the 1-hop region. ② Pre-define the area for resources transferred from other RS to other nodes in multi-hop region. ③ Allocates the actual resource in the next frame based on the information of the predefined multi-hop region. ④ Repeat steps ② and ③ until the burst reaches MS.

Next, in case of uplink, I) If the distance of MS-BS is single hop, resource is allocated for the MS. ii) If the distance of the MS-BS is multi-hop 1) Allocating resources for the RS between the MS and the single hop distance of the RS between the BS-MS. ② Pre-define the region for resources transferred from other RS to other node in uplink region. ③ Allocates the actual resource in the next frame based on the information of the predefined uplink region. ④ Repeat steps ② and ③ until the burst reaches the BS.

In FIG. 2, an example of configuring a frame by the process of FIG. 4 will be described in the case of multiple hops consisting of BS 201-RS2 203-RS3 204-MS5 209.

The burst transmitted from BS to MS5 is transmitted from BS to RS2 in the nth frame, from RS2 to RS3 in the (n + 1) th frame, and from RS3 to MS5 in the (n + 2) th frame. Where n is any point in time.

To this end, the BS allocates an area for transmitting bursts from the BS to RS2 in the 1-hop region of the nth frame, and simultaneously allocates an area for transmitting bursts from RS2 to RS3 to the multi-hop region of the (n + 1) th frame. Assign to

In the (n + 1) th frame, the BS actually allocates the pre-allocated RS2-RS3 burst in that region in the nth frame, and simultaneously transmits the burst from RS3 to MS5 in the multi-hop region of the (n + 2) th frame. Allocate the area beforehand.

In the (n + 2) th frame, the BS actually allocates a pre-allocated RS3-MS5 burst to the region in the (n + 1) th frame.

In this way, resources are allocated for multi-hop nodes.

2. Frame transmission method in relay station

When the RS receives the frame of FIG. 3, the RS operates as shown in FIG. 7 under the configuration of FIG. 6 because the processing procedure has to be changed according to an area within the frame.

The determination unit 620 analyzes the frame received and transmitted by the transceiver 610 to determine whether to simply amplify each area within the frame and deliver the result to a lower node or after processing. At this time, the determination is performed based on the received MAP information. As a result, it is determined that the direct region and the 1-hop region are simply amplified and delivered, and the multi-hop region is processed by the RS and then delivered to the lower node.

The amplifying unit 630 amplifies and outputs the signal strength to the intra-frame region, ie, the region of the direct region and the 1-hop region, which the determination unit simply determines to amplify, and transmits the signal strength to the transceiver.

The processor 640 performs a predetermined process on the intra-frame region, that is, the multi-hop region, which is determined to be processed by the determination unit, and loads it on the next frame to output to the transceiver. Hereinafter, it demonstrates in detail, referring FIG. 7 and FIG.

2.1. Direct Region (301)

7 illustrates a process of the direct region 301.

While receiving the broadcast frame from the BS, the signal is amplified by an analog or digital amplifier and broadcasted immediately. At the time of amplification, a filter or the like may be used to slightly improve the signal quality.

The reception amplifier 701 amplifies the received signal using an analog or digital method. Divider 702 distributes the same signal to transmit amplifier 703 and demodulator 704. The transmission amplifier 703 amplifies a signal to be transmitted by using an analog or digital method. The demodulator 704 demodulates the analog signal into a digital signal. The decoder 705 decodes the encoded data. The MAC module 706 analyzes the FCH and the MAP based on the received data.

At the same time, the MAC processing unit 704 restores the information carried on the FCH and MAP to grasp the configuration state of the frame.

2.2. Multihop bursts in multi-hop regions and uplink regions

8 is a diagram illustrating the processing of a multi-hop region.

Based on the MAP information received in advance, it is determined whether or not the area is transmitted through itself.

In the case of an area transmitted through itself, encoding, modulation, and amplification processes are performed except for packet processing in the MAC, and then transmitted to the next node in the next frame.

To this end, each block of FIG. 8 performs a necessary function.

The reception amplifier 801 amplifies the received signal by using an analog or digital method. The demodulator 802 demodulates the analog signal into a digital signal. The decoder 803 decodes the encoded data. The MAC module 804 transmits the received data to the encoder 805 to retransmit the received data based on the MAP information. The encoder 805 encodes the data. The modulator 806 modulates the digital signal into an analog signal. The transmission amplifier 807 amplifies a signal to be transmitted by using an analog or digital method.

Other areas are ignored.

Functions used in the method of a communication method using a frame for an MMR (Mobile Multi-hop Relay) system according to the present invention can be implemented as computer readable codes on a computer readable recording medium. . The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disks, optical data storage devices, and the like, which may also be implemented in the form of carrier waves (for example, transmission over the Internet). do. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. And functional programs, codes and code segments for implementing the present invention can be easily inferred by programmers in the art to which the present invention belongs.

As described above, optimal embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the frame structure for the MMR (Mobile Multi-hop Relay) system and the communication method using the frame according to the present invention can add a new node RS without modification to the existing MS, the existing standard In addition to the transmission of the single hop node of the multi-hop node can be performed. It also minimizes modifications to the BS.

Claims (5)

A communication method in an MMR system including a base station, a plurality of mobile terminals, and a relay station connecting the base station and mobile terminals, (a) the base station generating and outputting a frame having a different area in which a burst delivered to the mobile terminals is carried according to the number of hops to the mobile terminals; (b) determining whether a simple relay is performed for each region of the frame after the relay station receives the frame; And (c) the relay station if the burst is in a first region including a preamble and a MAP or in a second region allocated for a burst delivered to the first mobile terminal or the relay station at a single hop distance from the base station; Amplifying and delivering the burst to a lower node; And (d) If the burst is determined as a result of step (b), if the burst is within a third area allocated for the burst transmitted to the second mobile terminal or the relay station at least two hops away from the base station, the relay station may receive lower node information. And pre-allocating and transmitting the signal to a lower node in a next frame. The method of claim 1, wherein the frame A downlink region including the first region, the second region and the third region; And And an uplink region including a burst transmitted from the mobile terminals or the relay station to the base station. The method of claim 2, wherein the second region and the third region is A communication method in an MMR system, characterized in that its size is variable. The method of claim 1, wherein step (a) (a1) determining whether there is an area for multi-hop allocated in a previous frame; (a2) if it is determined in step (a1), allocating the remaining downlink region except for the multi-hop region as a single hop region, and if not present, allocating the downlink region as a single hop region; (a3) whether the allocation to the nodes accessing the base station is completed Determining; (a4) if the allocation is completed, ending the current frame generation process; if the allocation is not completed, determining whether the first mobile terminal receives a burst in the next frame of the current frame; (a5) if it is not received, allocating a burst transmitted to the first mobile terminal in an area for multi-hop of a next frame and storing the information if it is not received; And (a6) As a result of the determination in the step (a4), if it is received, the first mobile terminal determines whether the multi-hop mobile terminal, and if the multi-hop mobile terminal, the burst delivered to the first mobile terminal in the area for multi-hop of the next frame And allocating and storing the information, allocating a burst delivered to the first mobile terminal in a single hop region if not the multi-hop mobile terminal, and storing the information. Communication method. delete

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