KR20100048855A - Method for receiving the transparent relay station identification information - Google Patents

Abstract

PURPOSE: A method for receiving transparent relay station identification information is provided to enable efficient handover between repeaters by identifying a transparent repeater based on the identification information received from the transparent repeater. CONSTITUTION: A terminal receives the preamble offset information of a transparent repeater, which is activated in a transparent mode, through a broadcast or control channel. In addition, the terminal uses the offset information to adjust the preamble symbol and timing of the transparent repeater, and receives a transparent relay preamble including the identifier of the transparent. The terminal classifies the transparent repeater by using the identifier of the transparent repeater.

Description

Method for receiving the transparent relay station identification information

The present invention relates to a wireless communication system, and more particularly, to a method for a terminal to receive transparent repeater identification information in a wireless communication system.

Relay station is a widely used technology for eliminating shadow areas in mobile communication systems. In the past, the repeater method was limited to the function of a repeater to simply amplify the signal, but recently it has been developed into a more intelligent form.

The repeater can extend the service coverage area by the cell expansion of the base station, and also has an advantage of improving the transmission speed of the terminal (data throughput). Furthermore, the repeater technology has advantages in reducing base station extension costs and maintenance costs of back-haul communication networks in next generation mobile communication systems. The frame structure used by such a repeater will be described.

1 is a diagram illustrating a frame structure used in a broadband wireless access system (eg, IEEE 802.16).

Referring to FIG. 1, a horizontal axis of an frame represents an Orthogonal Frequency Division Multiplexing (OFDMA) symbol as a unit of time, and a vertical axis of the frame represents a logical number of a subchannel as a unit of frequency. In FIG. 1, one frame is divided into a data sequence channel for a predetermined time period by physical characteristics. That is, one frame includes one downlink subframe and one uplink subframe.

In this case, the downlink subframe includes one preamble, a frame control header (FCH), a downlink map (DL-MAP), an uplink map (UL-MAP), and one or more data bursts. Can be. In addition, the uplink subframe may include one or more uplink data bursts and ranging subchannels.

In FIG. 1, the preamble is specific sequence data located in the first symbol of every frame, which is used by the terminal to synchronize with the base station or to estimate a channel. The FCH is used to provide channel allocation information and channel code information related to the DL-MAP. DL-MAP / UL-MAP is a Media Access Control (MAC) message used to inform UE of channel resource allocation in downlink / uplink. In addition, a data burst represents a unit of data for transmission from the base station to the terminal or from the terminal to the base station.

A downlink channel descriptor (DCD) that can be used in FIG. 1 indicates a MAC message for indicating physical characteristics in a downlink channel, and an uplink channel descriptor (UCD) indicates an uplink channel descriptor. Represents a MAC message for indicating physical characteristics.

In the case of downlink, referring to FIG. 1, the terminal detects a preamble transmitted from the base station and synchronizes with the base station. Thereafter, the downlink map may be decoded using information obtained from the frame control header (FCH). The base station may transmit scheduling information for downlink or uplink resource allocation to the terminal every frame (for example, 5 ms) using a downlink or uplink map (DL-MAP / UL-MAP) message.

A method for recognizing a base station by a terminal is as described above, but a method for recognizing a repeater in which the terminal operates in a transparent mode has not been proposed or defined yet.

An object of the present invention is to provide a method for a terminal to receive identification information of a transparent repeater.

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

In order to achieve the above technical problem, a method of receiving identification information of a transparent repeater according to the present invention includes a preamble offset of a transparent repeater in which a terminal operates in a transparent mode through a broadcast channel or a control channel from a base station. Receiving information; The terminal using the offset information to match a timing with a preamble symbol of the transparent repeater and receiving a transparent repeater preamble including an identifier of the transparent repeater from the transparent repeater; And identifying, by the terminal, the transparent repeater using an identifier of the transparent repeater.

According to the method of receiving transparent repeater identification information according to the present invention, there are various advantages.

First, when the terminal receives the identification information from the transparent repeater, the transparent repeater can be identified to enable efficient handover between the repeaters.

In a multi-hop relay environment, as the terminal receives identification information from the transparent repeater, the relay can be efficiently supported to the terminal in the base station.

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

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description set forth below in conjunction with the appended drawings is intended to explain exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. The following detailed description includes specific details to assist in a thorough understanding of the present invention. However, one of ordinary skill in the art appreciates that the present invention may be practiced without these specific details. For example, the following description will focus on certain terms, but need not be limited to these terms and may refer to the same meaning even when referred to as any term. In addition, the same or similar components throughout the present specification will be described using the same reference numerals.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise.

The technique disclosed below may be used in various communication systems, which may provide various communication services such as voice, packet data, and the like. The technology of the communication system can be used for downlink or uplink. A base station may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, an ABS, and the like. In addition, a mobile station (MS) may be replaced with terms such as a user equipment (UE), a subscriber station (SS), a mobile subscriber station (MSS), an AMS, or a mobile terminal.

In addition, the transmitting end refers to a node transmitting data or voice service, and the receiving end refers to a node receiving data or voice service. Therefore, in uplink, a terminal may be a transmitting end and a base station may be a receiving end. Similarly, in downlink, a terminal may be a receiving end and a base station may be a transmitting end.

On the other hand, the terminal of the present invention PDA (Personal Digital Assistant), cellular phone, PCS (Personal Communication Service) phone, GSM (Global System for Mobile) phone, WCDMA (Wideband CDMA) phone, MBS (Mobile Broadband System) phone This can be used.

Embodiments of the present invention may be supported by standard documents disclosed in at least one of the Institute of Electrical and Electronics Engineers (IEEE) 802 system, the 3GPP system, the 3GPP LTE system, and the 3GPP2 system, which are wireless access systems. That is, steps or parts which are not described to clearly reveal the technical spirit of the present invention among the embodiments of the present invention may be supported by the above documents. In addition, all terms disclosed in the present document can be described by the above standard document. In particular, embodiments of the present invention may be supported by documents such as standard documents of the IEEE 802.16 system, P802.16-2004, P802.16e-2005, and P802.16Rev2.

Specific terms used in the following description are provided to help the understanding of the present invention, and the use of the specific terms may be modified in other forms without departing from the technical spirit of the present invention.

For example, in the embodiments of the present invention, the terms subordinate relay station and superordinate relay station are used. In this case, the lower repeater and the upper repeater are terms used relatively to each other, and the base station is located at a higher node than the first repeater (odd-hop repeater), and the first repeater is located at a higher node than the second repeater (even-hop repeater). It may correspond to an upper repeater of the first repeater.

A frame is a sequence of data for a fixed time used by physical specifications. Orthogonal Frequency Division Multiple Access (OFDMA) frames include an uplink frame and a downlink frame. In the IEEE 802.16m system, a super frame of 20 msec length may include four frames of 5 ms length each. In addition, the frames of 5 msec length may include eight subframes.

2 is a diagram illustrating an example of a frame structure that may be used in embodiments of the present invention.

Referring to FIG. 2, one super frame includes one or more frames (eg, F0, F1, ..., F3), and one frame includes one or more subframes (eg, , SF0, SF1, ..., SF7). In addition, one subframe may include one or more OFDMA symbols. The length and number of superframes, subframes and symbols can be adjusted according to user requirements or system environment. In embodiments of the present invention, the term 'subframe' is used. In this case, the 'subframe' refers to all lower frame structures generated by dividing one frame into a predetermined length.

The subframe structure used in the embodiments of the present invention may be configured by dividing a generally used frame into one or more subframes. In this case, the number of subframes included in one frame may be determined by the number of symbols constituting the subframe. For example, suppose that one frame is composed of 48 symbols. If one subframe consists of six symbols, one frame may consist of eight subframes. In addition, if one subframe consists of 12 symbols, one frame may consist of four subframes.

As shown in FIG. 2, it is assumed that one super frame has a length of 20 msec and a frame has a length of 5 msec. That is, one super frame may consist of four frames. In addition, one frame has a frame structure consisting of eight subframes. In this case, one subframe may be configured as six OFDMA symbols. Each super frame may include a super frame header (SFH). The super frame header (SFH) may be referred to as superframe based control signaling.

3 is a diagram illustrating an example of a transmission position of a synchronization channel used in embodiments of the present invention.

Referring to FIG. 3, one synchronization channel (SCH) may consist of one or more OFDM symbols. In this case, in the embodiments of the present invention, the synchronization channel may be transmitted with a transmission period (for example, 5 msec). In the embodiments of the present invention, the number of OFDM symbols constituting the sync channel and the transmission period of the sync channel may be changed according to user requirements or channel environment.

The frame structure to be described below represents a case in which a time division duplex (TDD) is supported within one frame of a 5 msec period. However, it can be extended to Frequency Division Duplex (FDD) and can be interpreted as TDD / FDD mode operation for a plurality of frames. In addition, the division of each region may be set in a subframe unit for a frame composed of one or more subframes or in a frame unit for one or more frames.

4 is a diagram illustrating an example of a frame structure composed of a single-directional zone supporting a multi-hop repeater in an IEEE 802.16m system.

Referring to FIG. 4, a relay station (RS) may be classified into an odd hop repeater and an even hop repeater according to the number of hops with a base station. The downlink of an odd hop repeater may include a 16m downlink transmission zone (16m DL Transmit Zone) and a 16m downlink reception zone (16m DL Receive Zone), and the uplink of an odd hop repeater may have a 16m uplink reception zone (16m). UL Receive Zone) and 16m uplink transmission zone (16m UL Transmit Zone) may be included.

First, the frame structure of the base station is described. The 16m downlink transmission zone (16m DL transmit zone) is a downlink period of the base station, the base station may provide downlink transmission to the 16m repeater or 16m terminal. The 16m UL Receive Zone is an uplink section of the base station, and is a section in which a 16m terminal or a 16m repeater provides uplink transmission to the base station.

Here, a repeater located at a higher node than the node where the current repeater is located, and an odd hop or an even hop away from the base station may be referred to as an upper odd hop repeater and an upper even hop repeater, respectively. On the contrary, the repeater located at a lower node than the node where the current repeater is located and the odd hop or even hop away from the base station may be referred to as the lower odd hop repeater and the lower even hop repeater, respectively.

Next, an odd hop repeater frame structure will be described. The 16m downlink transmission zone of the odd-hop repeater is a downlink section of the repeater and provides downlink transmission to the 16m terminal or lower even-hop repeater. In a 16m DL Receive Zone, a base station or an upper even hop repeater provides downlink transmission to an odd hop repeater. The 16m UL Transmit Zone is an interval for providing uplink transmission to a base station or an upper even-hop repeater as an uplink section of a repeater. In a 16m UL Receive Zone, a 16m terminal or a lower even-hop repeater provides uplink transmission to an odd hop repeater.

FIG. 5 is a diagram illustrating an example of a frame structure including a bidirectional zone supporting a multi-hop repeater in an IEEE 802.16m system.

Referring to FIG. 5, in the frame structure of an odd hop repeater, an odd hop repeater may receive a signal from a base station, an upper even hop repeater, and a lower even hop repeater through a bi-directional receive zone during a downlink period. Can be.

In addition, the odd hop repeater may transmit a signal to a base station, an upper even hop repeater, and a lower even hop repeater through a bi-directional transmit zone during an uplink period. The 16m DL Access Zone is a section in which a 16m base station or a 16m repeater transmits a signal to a 16m terminal. The 16m UL Access Zone is a section in which a 16m base station or a 16m repeater receives a signal from a 16m terminal.

6 is a diagram illustrating an example of a frame structure supporting a multi-hop repeater in an IEEE 802.16m system.

Referring to FIG. 6, it can be seen that the bidirectional zone is an integrated frame structure based on the frame structure of the unidirectional zone illustrated in FIG. 5. In an odd hop repeater frame structure, an odd hop repeater may transmit a signal to a 16m terminal or a lower even hop repeater through a 16m downlink transmission zone (16m DL transmit zone) in a downlink period. In addition, the odd-hop repeater is a section in which a 16m downlink reception zone (16m DL Receive Zone) of the downlink section receives a signal from a base station or an upper even-hop repeater.

The odd hop repeater may bidirectionally transmit a signal to a base station or a lower even hop repeater through a 16m network coding receive zone during a downlink period.

FIG. 7 is a diagram illustrating a frame structure for a transparent RS.

Referring to FIG. 7, the transparent repeater may receive a signal from a base station or an upper even hop repeater through a 16m downlink reception zone in a downlink period. In addition, the transparent repeater may transmit a signal to a base station or an upper even-hop repeater through a 16m uplink transmission zone during an uplink period.

The repeater may be divided into two operation modes according to whether to transmit a preamble and a broadcast channel. That is, it can be divided into a transparent mode and a non-transparent mode. The repeater operating in the non-transparent mode may transmit a preamble, control information (Superframe Header, BCH), and resource allocation information (A-MAP or USCCH: Unicast Service Control CHannel) at the beginning of the super frame. In contrast, a relay RS operating in a transparent mode may not transmit preamble, control information, resource allocation information, and the like.

In a wireless communication system in which the channel environment between the base station and the terminal is continuously changed, synchronization and synchronization between the base station and the terminal must be synchronized for successful transmission and reception of data. In this case, the base station may insert a preamble for synchronization in a portion of the transmitted frame so that the terminals can synchronize. In this way, the terminals may synchronize with respect to the downlink channel through the preamble. In addition, the base station may use a separate synchronization channel.

In a wireless communication system using a repeater, a terminal may receive preambles, control information, and resource allocation information from a base station for receiving and demodulating data, and may receive data transmitted by the repeater based on these information. In this case, the terminal may recognize the transparent repeater to demodulate and receive data. Hereinafter, a method for demodulating and receiving data by a terminal recognizing a transparent repeater will be described.

8 is a diagram illustrating a frame structure of a base station and a transparent repeater for a terminal to recognize a transparent repeater in an IEEE 802.16m system.

Referring to FIG. 8A, a primary synchronization signal may be transmitted through a primary advanced preamble (PA-Preamble) located in the front part of a first frame in a superframe of a base station. In addition, the sub-synchronization signal may be transmitted from the second frame through a secondary preamble (SA-Preamble) located in the front portion of each frame.

Referring to FIG. 8B, the transparent repeater may transmit only a relay advanced preamble (RA-Preamble) without transmitting a main preamble. In this case, the repeater cell ID information may be transmitted through the RA preamble. Meanwhile, a relay station identifier (Relay STID), a relay amble, or the like may be transmitted instead of the cell ID of the repeater.

The repeater preamble may be fixedly transmitted from the first symbol of the 16m downlink transmission zone. In addition, it may be transmitted in 5msec unit (or frame unit). One or more repeater preambles may be transmitted in one superframe. In this case, the repeater preamble may use a repeater cell ID, a relay amble, a repeater identifier, or a specific signal indicating the repeater as a reference signal.

An upper repeater (non-transparent repeater) of a base station or a transparent repeater may transmit a repeater preamble offset value to a transparent repeater and a terminal, which are lower repeaters, through a broadcast channel or a specific control channel.

In this case, the repeater preamble offset (RA-Preamble offset) is from the time when the sub-preamble of the base station or higher repeater is transmitted to the time when the transmission of the preamble symbol of the transparent repeater starts, from the time of transmitting the first symbol of the superframe to the transparent repeater This indicates up to the point in time at which the preamble symbol is transmitted. In addition, the repeater preamble offset may be variously expressed from the first symbol transmission time of the frame to the time point at which the transmission of the preamble symbol of the transparent repeater starts. That is, the offset is not limited to a specific point of time as a reference.

The transparent repeater may transmit a repeater preamble when the transparent repeater attempts to enter the initial network, or when the operating mode of the repeater is changed from the non-transparent repeater mode to the transparent repeater mode. The terminal may receive the repeater preamble offset information from the base station or the upper repeater of the transparent repeater to determine the reception time of the transparent repeater preamble. Accordingly, the terminal may recognize the transparent repeater using the repeater cell ID and the repeater preamble offset information included in the transparent repeater preamble.

The repeater preamble symbol offset information may be represented by 6 bits. This offset relates to assigning a start time in a given field in a broadcast channel or control channel.

The embodiments described above are the components and features of the present invention are combined in a predetermined form. Each component or feature is to be considered optional unless stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. It is also possible to combine some of the components and / or features to form an embodiment of the invention. The order of the operations described in the embodiments of the present invention may be changed. Some configurations or features of certain embodiments may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments. It is obvious that the claims may be combined to form an embodiment by combining claims that do not have an explicit citation relationship in the claims or as new claims by post-application correction.

Embodiments according to the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of a hardware implementation, an embodiment of the present invention may include one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), FPGAs ( Field Programmable Gate Arrays), processors, controllers, microcontrollers, microprocessors, and the like.

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

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

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

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as part of the detailed description in order to provide a thorough understanding of the present invention, provide an embodiment of the present invention and together with the description, illustrate the technical idea of the present invention.

1 illustrates a frame structure used in a broadband wireless access system (eg, IEEE 802.16).

2 illustrates an example of a frame structure that can be used in embodiments of the present invention;

3 is a view showing an example of a transmission position of a synchronization channel used in embodiments of the present invention;

4 is a diagram illustrating an example of a frame structure composed of a single-directional zone supporting a multi-hop repeater in an IEEE 802.16m system;

5 is a diagram illustrating an example of a frame structure composed of a bidirectional zone supporting a multi-hop repeater in an IEEE 802.16m system;

6 is a diagram illustrating an example of a frame structure supporting a multi-hop repeater in an IEEE 802.16m system;

7 illustrates a frame structure for a transparent RS, and

8 is a diagram illustrating a frame structure of a base station and a transparent repeater for a terminal to recognize a transparent repeater in an IEEE 802.16m system.

Claims (5)

Receiving, by the terminal, preamble offset information of a transparent repeater operating in a transparent mode through a broadcast channel or a control channel from a base station; The terminal using the offset information to match a timing with a preamble symbol of the transparent repeater and receiving a transparent repeater preamble including an identifier of the transparent repeater from the transparent repeater; And And identifying, by the terminal, the transparent repeater using an identifier of the transparent repeater. The method of claim 1, And the transparent repeater preamble is transmitted from the first symbol of the downlink transmission zone of the transparent repeater. The method of claim 1, The transparent repeater preamble is transmitted in units of frames of the transparent repeater, transparent repeater identification information receiving method. The method of claim 1, And the preamble offset indicates from the transmission of the secondary advanced preamble (SA-P) symbol of the base station to the transmission time of the preamble symbol of the transparent repeater. The method of claim 1, And the preamble offset indicates from the transmission of the first symbol of the superframe or frame of the transparent repeater to the time of transmitting the preamble symbol of the transparent repeater.

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