KR20080063151A - Method for supporting short latency in mobile communication system - Google Patents

Abstract

A method for supporting short latency in a mobile communication system is provided to configure an existing subframe into plural temporal zones, use the temporal zones as a short latency dedicated zone, define dedicated channels in the short latency dedicated zone, and use a frame structure using the short latency dedicated zone and the dedicated channels, thereby processing data and services which requires short latency efficiently. A downlink SLZ(Short Latency Zone) is indicated in a first PUSC(Partial Usage Of Subchannels) zone. The SLZ will be at least one of PUSC, FUSC(Full Usage Of Subchannels), optional FUSC, AMC(Adaptive Modulation and Coding), and TUSC/TUSC2(Tile Usage Subchannel) zones. The location information of the SLZ is provided through pre-assigned information or broadcast information without using an UL-MAP(Uplink-MAP) message. An MS(Mobile Station) knows a section, to which the SLZ is provided, previously or receives the broadcast information to acquire the location of the SLZ. An SLDCCH(Short Latency Dedicated Control Channel) indicates the allocation information of an SLDDCH(Short Latency Dedicated Data Channel) and an SLDFCH(Short Latency Dedicated Feedback Channel). The allocation information includes a location in a subframe, and modulation and coding methods. Feedback for data transmitted in the SLZ is quickly performed to provide a feedback channel to support short latency.

Description

How to support short latency in mobile communication systems {METHOD FOR SUPPORTING SHORT LATENCY IN MOBILE COMMUNICATION SYSTEM}

The present invention relates to a mobile communication system, and more particularly, to a method for supporting short latency in transmitting and receiving a signal in a mobile communication system.

Currently, mobile communication systems are being developed to provide various services such as broadcasting, multimedia video, and multimedia messages. In particular, the fourth generation mobile communication systems are being developed to provide data transmission speeds of 100 Mbps or more for high speed mobile users and 1 Gbps or more data services for low speed mobile users, mainly for voice and packet data communication.

Meanwhile, in a mobile communication system, a multiple access scheme is considered to efficiently use a finite frequency resource. In addition, the mobile communication system considers a duplexing scheme that distinguishes bidirectional, that is, connection between uplink and downlink. One of the methods for considering such multiple access and multiplexing is Time Division Duplexing Orthogonal Frequency Division Multiple Access (TDD-OFDMA).

1A and 1B illustrate a general TDD-OFDMA frame structure and a TDD-OFDMA frame structure having multiple zones.

First, referring to FIG. 1A, a TDD-OFDMA frame is divided into a downlink subframe and an uplink subframe, and a transmission / reception time gap (TGT) and a reception / transmission time gap (RTG) are formed between the two subframes. Located. The downlink subframe includes a preamble area to which a preamble signal is transmitted and a control information area. The control information area includes a frame control header (FCH), DL-MAP, and UL-MAP.

Next, referring to FIG. 1B, the downlink subframe and the uplink subframe may be configured in different zones according to the subchannel configuration. Zone configuration information is included in the first zone located after the preamble, that is, partial usage of subchannels (PUSC). The zone configuration information may be designated using STC_DL_Zone_Switch_IE () or AAS_DL_IE ().

In FIGS. 1A and 1B, the solid line region represents a fixed region that must exist, and the dotted line region represents a variable region in which the size and existence of the region can be changed according to the cell environment and operation.

On the other hand, a short latency is required for high speed data transmission in a mobile communication system. However, not all packets require this short latency. For example, a Voice over IP (VoIP) packet using a Hybrid Automatic Repeat Request (Hybrid Automatic Repeat Request) may require a short latency.

 In the mobile communication system, a transmission scheme in a frame having a length of 5 msec takes 15 msec or more until the next data transmission or retransmission after the initial data transmission. However, for high speed real-time data transmission, data transmission or retransmission must be performed within 15 msec.

The present invention was devised to solve the above problems, and an object of the present invention is to provide a high speed data transmission method in a mobile communication system.

Another object of the present invention is to provide a frame structure for high speed data transmission in a mobile communication system.

The first method of the present invention; In a mobile communication system, a method for transmitting a downlink signal by a base station, the frame comprising a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, wherein the second region is a downlink subframe and Located in each of the uplink subframes, a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe, and the base station determines the downlink of the second region through the first region. Indicating a first specific region of a link subframe, and a second specific region receiving information on a dedicated channel to which data is transmitted or retransmitted within the first specific region and a feedback signal for the data; Indicating data through a first specific region; and transmitting data through a dedicated channel indicated through the first specific region. Transmitting or retransmitting, and receiving a feedback signal through the second specific region.

The second method of the present invention; In a mobile communication system, a method for transmitting an uplink signal of a mobile station, the frame comprising a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, wherein the second region is a downlink subframe and Located in each of the uplink subframes, a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe, and the mobile station transmits the second region through the first region of the current frame. Receiving a first specific region of the downlink subframe and a second specific region of the uplink subframe of the region, information on a dedicated channel to which data is transmitted or retransmitted within the second specific region, and information on the data Receiving a first specific region of a next frame receiving a feedback signal through the first specific region; And transmitting or retransmitting data through a dedicated channel indicated through a first specific region, and receiving a feedback signal through the first specific region of the next frame.

The third method of the present invention; In a mobile communication system, a method for receiving a downlink signal of a mobile station, the frame comprising a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, wherein the second region is a downlink subframe and Located in each uplink subframe, a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe, and the mobile station is configured to downlink the second region through the first region. Receiving a first specific region of a link subframe, and a second specific region receiving information on a dedicated channel to which data is transmitted or retransmitted and a feedback signal for the data within the first specific region. 1 process of receiving an indication through a specific region and receiving data through a dedicated channel indicated through the first specific region Comprises the step of transmitting a feedback signal through the process, and the second specific area of receiving material.

The fourth method of the present invention; In a mobile communication system, a method for receiving an uplink signal of a base station, the frame comprising a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, wherein the second region is a downlink subframe and Located in each of the uplink subframes, a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe, and the mobile station transmits the second region through the first region of the current frame. Indicating a first specific region of a downlink subframe and a second specific region of an uplink subframe, information on a dedicated channel to which data is transmitted or retransmitted within the second specific region, and information on the data Indicating a first specific region of a next frame for transmitting a feedback signal through the first specific region; And receiving or re-receiving data through a dedicated channel indicated through the first specific region, and transmitting a feedback signal through the first specific region of the next frame.

The fifth method of the present invention; In a mobile communication system, in a signal transmission / reception method of a base station, a frame includes a downlink subframe and an uplink subframe, and a first specific region and a second specific region are previously included in the downlink subframe and the uplink subframe. Instructing, through the first specific region, the second specific region to receive information on a dedicated channel to which data is transmitted or retransmitted and a feedback signal for the data, to the mobile station; Transmitting or retransmitting data through a dedicated channel indicated through the region; and receiving a feedback signal through the second specific region.

The sixth method of the present invention; In a mobile communication system, in a signal transmission / reception method of a mobile station, a frame includes a downlink subframe and an uplink subframe, and a first specific region and a second specific region are previously described in the downlink subframe and the uplink subframe. Setting the second specific area for receiving information on the dedicated channel to which data is transmitted or retransmitted and a feedback signal for the data from the base station through the first specific area; And receiving or re-receiving data through a dedicated channel indicated through the region, and transmitting a feedback signal through the second specific region.

According to the present invention, a frame structure using an existing subframe as a plurality of time domains, using the time domain as a short latency dedicated zone, defining dedicated channels in the dedicated zone, and using the dedicated zone and the dedicated channel in a communication system is provided. The use has the advantage of efficiently processing data and services requiring short latency.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, only parts necessary for understanding the operation of the present invention will be described, and other background art will be omitted so as not to distract from the gist of the present invention.

The present invention proposes a transmission / reception method supporting short latency in a mobile communication system. In particular, the present invention proposes a signal transmission / reception scheme supporting short latency on a frame basis divided into multiple zones. Accordingly, the present invention newly proposes a frame structure capable of satisfying the requirement for short latency while being compatible with the existing frame length and structure.

The frame in the present invention is a transmission region that supports short latency and includes at least one zone, that is, a short latency support region. The frame may be a time division duplexing orthogonal frequency division multiple access (TDD-OFDMA) frame. The short latency support area in the present invention may use a newly defined dedicated zone as follows.

1. Short Latency Zone (SLZ): An area in which data requiring short latency is transmitted. The short latency zones exist in uplink and downlink, respectively. The short latency zone is used preferentially for data requiring short latency, and may be used for data other than data requiring short latency in terms of resource utilization. The following channels are defined for the operation of the short latency zone. In addition, one subframe may consist of only a short latency zone.

2. Short Latency Dedicated Control Channel (SLDCCH): A channel for transmitting short latency dedicated control information, including data burst assignment information and feedback channel assignment information.

3. Short Latency Dedicated Data Channel (SLDDCH): A channel through which short latency-only data is transmitted.

4. Short Latency Dedicated Feedback Channel (SLDFCH): A channel through which a short latency-only feedback signal is transmitted.

Next, a description will be made of a data transmission scheme supporting short latency by dividing it into downlink and uplink.

First, in the downlink, a short latency zone is located in a downlink subframe, and a dedicated channel for supporting this is located in each of the uplink and downlink subframes. A more detailed description will be given with reference to FIG. 2.

2 is a diagram illustrating a TDD-OFDMA frame structure for supporting short latency in downlink data transmission proposed in the present invention.

Referring to FIG. 2, the downlink subframe includes a short latency zone. For example, reference numeral 200 becomes a short latency zone in the L-1th frame. The short latency zone 200 provides the SLDDCH and SLDCCH. The SLDDCH transmits data requiring short latency. In addition, in order to support short latency, the SLDFCH of an uplink subframe of the same frame transmits feedback on data transmitted through the SLDDCH. The short latency zone 200 may be configured as any zone in the downlink subframe as shown in FIG. 1B. In addition, the region 210 of FIG. 2 may be configured as any burst region in the uplink subframe illustrated in FIG. 1B. In addition, the regions 200 and 210 of FIG. 2 are designated to perform fast signal transmission in consideration of data processing processing delay time.

The processing delay time that should be considered for the areas 200 and 210 to be designated will now be described. Processing delay time required for data transmission can be classified into three types. First, it is a time before the transmitter acquires resource allocation information, encodes data, and transmits the data. Secondly, it is a time before the receiver demodulates and decodes the received data to encode and transmit a feedback message (ACK / NACK) according to whether an error is detected. Third, it is the time before the transmitting end receives the feedback message, obtains resource allocation information, encodes the data, and transmits or retransmits the data.

Since the base station schedules the downlink data transmission, only the second and third delay time are considered. For example, when a hybrid automatic repeat request (HQ-ARQ) scheme is applied for downlink data transmission in a period of about 0.9 ms, the minimum allowable delay times are 0 ms, about 1.8 ms, and about 0.9 ms. Here, the first delay time is 0ms, the second delay time is about 1.8ms, and the third delay time is about 0.9ms.

3A and 3B illustrate downlink data transmission and reception supporting short latency using a frame structure proposed by the present invention.

Referring to FIG. 3A, control information such as burst allocation information is provided through the first zone in every frame. Data requiring short latency is then transmitted in the short latency zones 300, 310, 320 after the first zone. Wherein the short latency zone includes a SLDDCH. In this case, the SLDCCH is located in the first PUSC zone.

When the base station transmits data on the SLDDCH of the short latency zone, the mobile station receives and decodes it. When the time taken for decoding is called a reception processing time, the mobile station feeds back to the base station whether or not an error of received data is detected through the SLDFCHs 305, 315, and 325 when the reception processing time expires.

The base station receives a feedback signal from the mobile station and performs encoding on data to be transmitted through scheduling. If the time taken for such processing is called transmission processing time, the base station should transmit or retransmit allocation control information and data to the mobile station when the transmission processing time expires. However, as shown in FIG. 3A, it can be seen that the transmission processing time expiration time of the base station deviates from the time interval corresponding to the first zone of the downlink subframe in the Lth frame in which allocation control information is already transmitted. Accordingly, the base station transmits allocation information in the first zone of the downlink subframe of the L + 1th frame. Considering the length of one frame as 5ms, it takes 10ms from the first burst allocation information transmission and data transmission or retransmission to the next burst allocation information transmission and data transmission or retransmission.

Meanwhile, in FIG. 3A, the allocation information includes allocation information of the feedback channel of the uplink subframe, and the feedback channel allocation information of the uplink subframe in the present invention indicates an uplink burst region in the same frame as the short latency zone. . Conventionally, the uplink feedback channel allocation information in the current frame indicates the uplink burst region of the next frame.

Next, referring to FIG. 3B, short latency zones 350, 360, and 370 are included in a downlink subframe. The short latency zone includes SLDCCH and SLDDCH corresponding to each zone. The mobile station performs feedback in the manner indicated in the SLDCCH or in a previously promised manner. More detailed description thereof will be described with reference to FIG. 6.

When the base station performs data transmission on the SLDDCH of the short latency zone, the mobile station performs decoding processing on the received data. When the time taken for processing is called a reception processing time, the mobile station feeds back to the base station whether an error of received data is detected through the SLDFCHs 305, 315, and 325 at the time when the reception processing expires.

The base station receives the signal fed back from the mobile station and prepares for data transmission or retransmission. The base station performs signal processing such as encoding for data transmission. When the time required for the signal processing is called a transmission processing time, the base station should transmit or retransmit allocation control information and data to the mobile station at the time when the transmission processing time expires. Here, the difference from that shown in FIG. 3A is as follows. A time interval corresponding to the short latency zone 360 of the L-th frame is out of the time interval corresponding to the first zone of the downlink subframe of the L-th frame in which the allocation information has expired. Did not escape This is because the downlink subframe is divided into a plurality of zones and control information is provided to each zone to support short latency.

Accordingly, the base station may perform allocation information and data transmission or retransmission through the short latency zone 360 in the Lth frame rather than in the L + 1th frame. Therefore, considering a frame having a length of 5ms, data transmitted in the L-1th frame may be retransmitted in the Lth frame. This time is 5ms.

As described above, data burst allocation in the short latency zone is indicated through the SLDCCH, data transmission or retransmission is performed through the SLDDCH, and feedback is performed through the SLDFCH. As such, when considering data transmission, retransmission, and feedback, a short latency zone should be configured in a frame in consideration of a large data processing delay time.

The short latency zone of the downlink subframe in the TDD frame structure may be configured as follows. Assume using the WiMAX profile system parameter. In the WiMAX profile, one OFDM symbol interval is 102.9us, the frame length is 5 ms (48 symbol intervals including TTG), and the number of OFDM symbols in the downlink subframe and the number of the OFDM symbols in the uplink subframe are 29:18. Have The UL subchannel consists of three OFDM symbols. The base station should transmit the signal with reference to the second and third processing delay time of 1.8 ms and considering 18 symbol periods.

Based on the above conditions, one short latency zone in a downlink subframe may consist of 9 symbols. This is represented by Equation 1 below.

In Equation 1, the short latency zone of the downlink subframe may include SLDCCH and SLDDCH, and the SLDFCH may be configured as a full frequency band or a partial frequency band of a corresponding symbol period.

Next, a method of supporting short latency in uplink will be described.

4 illustrates a TDD-OFDMA frame structure for supporting short latency in uplink data transmission proposed in the present invention.

Referring to FIG. 4, the uplink subframe of the L-1th frame includes a short latency zone provided with SLDDCH. Allocation control information and feedback allocation information for the SLDDCH in the short latency zone are indicated in a downlink subframe. That is, the SLDCCH is provided to indicate allocation control information for the zone in the downlink subframe of the L-1 th frame before the short latency zone period in the uplink subframe. The feedback on the data transmitted on the SLDDCH is provided on the SLDFCH of the downlink subframe of the L-th frame indicated by the SLDCCH. Here, SLDCCH and SLDFCH are configured in OFDMA form. The short latency zone may consist of at least one zone in the content link subframe shown in FIG. 1B. 4 shows that the areas are determined in consideration of transmission and reception processing time for uplink data.

In the uplink data transmission, the above-described first to third delay times must be considered in order for the regions 400 and 410 to be determined. For example, the minimum allowable delay times when the hybrid ARQ (H-ARQ) operation is applied for uplink data transmission in a period of about 0.9 ms are about 0.9 ms, about 1.8 ms, and about 0.9 ms, respectively.

5A and 5B illustrate uplink data transmission and reception supporting short latency using a frame structure proposed by the present invention.

Referring to FIG. 5A, the SLDCCH included in the first zone in each frame provides allocation information related to the SLDDCH and corresponding SLDFCH allocation information. As such, when the base station transmits allocation information to the mobile station through the SLDCCH, the mobile station transmits data through the SLDDCH in the short latency zone of the uplink subframe after demodulating the allocation information. Here, the time taken for the above-mentioned process processing is called transmission processing time.

After the base station decodes the data received from the mobile station, it feeds back whether or not an error is detected through a predetermined SLDFCH. The burst allocation information is transmitted through the SLDCCH so that the mobile station can transmit or retransmit data. Here, the time taken for the above process is referred to as a receive process time.

As described above, the first zone of the downlink subframe of the L-th frame in which the allocation information is transmitted in the first zone and then the transmission processing time at the mobile station and the reception processing time at the base station expires has already been transmitted. It can be seen that out of the time interval corresponding to. Accordingly, the base station may transmit feedback and control information in the first zone of the downlink subframe of the L + 1th frame. Therefore, considering that the length of one frame is 5ms in the WiMAX profile, it takes 10ms from the first burst allocation information transmission and data transmission or retransmission to the next burst allocation information transmission and data transmission or retransmission.

Referring next to FIG. 5B, the base station transmits allocation information through the SLDCCH region 550 of the downlink subframe of the L-1th frame, and the mobile station transmits a short latency zone of the uplink subframe of the L-1th frame. If the data transmission and reception process has been completed before 555, the mobile station can transmit data through the short latency zone 505. In addition, the base station receives data through the short latency zone 505 of the L-1th frame, and if the processing thereof is completed before SLDCCH and SLDFCH of the downlink subframe of the Lth frame, the base station of the Lth frame Feedback and retransmission allocation information for data transmission may be transmitted to the mobile station through the SLDCCH and SLDFCH regions 560. Accordingly, the mobile station can perform transmission or retransmission for data transmission in the L-1th frame in the short latency zone 515 in the Lth frame. Considering that the length of one frame is 5ms, the time required for the mobile station to transmit data in the L-1th frame and the data transmission or retransmission in the Lth frame is 5ms. That is, the mobile station receives uplink short latency zone information in the downlink subframe of the L-1th frame and receives burst allocation information in the zone. Then, the mobile station transmits data at the assigned burst position in the uplink short latency zone of the L-1th frame and receives feedback from the base station through the downlink subframe of the Lth frame. The mobile station then transmits or retransmits data in the short latency zone in the uplink subframe of the L-th frame according to the feedback information.

A short latency zone configuration method of an uplink subframe in a TDD frame structure is as follows. For example, use WiMAX profile system parameters as in downlink. In the uplink transmission, the first, second and third delays refer to 1.8 ms. And to satisfy the HARQ retransmission delay of the frame length. In addition, it is assumed that the downlink control channel is configured in units of 1 symbol. It must also be transmitted within the (29, 18) TDD ratio.

Based on the above conditions, one short latency zone in an uplink subframe may consist of 11 symbol periods or less.

As shown in Equation 2, the uplink short latency zone is configured in the frame in consideration of the data transmission / reception processing delay time to support the short latency.

6 illustrates positions of dedicated channels for downlink short latency support according to an embodiment of the present invention.

Referring to FIG. 6, a downlink short latency zone in a downlink subframe is indicated in the first PUSC zone 600. The short latency zone may be any one or more of PUSC, FUSC, optional FUSC, AMC, TUSC (Tile Usage Subchannel) / TUSC 2 zone in FIG. 1B. In addition, a new subchannel configuration scheme may be applied.

In addition, the location information of the short latency zone may be provided through predetermined information or broadcast information without using a UL-MAP message. That is, the mobile station may know the section in which the short latency zone is provided in advance or may receive broadcast information to obtain the location of the short latency zone. And the short latency zone includes SLDCCH and SLDDCH. Meanwhile, the SLDCCH indicates allocation information of the SLDDCH and the SLDFCH. The allocation information includes a position in a subframe, a modulation and coding scheme, and the like. Feedback on data transmitted in the short latency zone is performed quickly to provide a short feedback channel to support short latency.

7 is a flowchart illustrating operation of a base station and a mobile station using a short latency zone of downlink according to an embodiment of the present invention.

Referring to FIG. 7, the base station 700 provides location information of a short latency zone through DL_MAP_IE of the first PUSC zone (step 702). In this case, step 702 may be omitted by a preset position indicating method in the system. The base station 700 then provides the SLDDCH location and control information over the SLDCCH in a short latency zone (step 704). Then, the base station 700 transmits data at the location of the SLDDCH designated by the SLDCCH (step 706).

The mobile station 750 performs a reception process of decoding a signal in the burst area allocated to the mobile station by using the SLDDCH and control information transmitted through the SLDCCH (step 708). The mobile station 750 then feeds back the data decoding result to the base station 700 via the designated SLDFCH (step 710).

The base station 700 performs transmission processing such as scheduling according to the feedback information received from the mobile station 750 (step 712). According to the processing result, the base station 700 performs step 704 or step 706. If resource allocation information and control information are added or changed, step 704 is performed, otherwise step 706 is performed. That is, the SLDCCH for subsequent transmission and retransmission of data may be omitted according to a resource allocation method. The interval from step 3 to step 6 is called latency according to retransmission. In order to perform a quick transmission, the position of the short latency zone may be fixed until it is changed after designation once. However, a control message for notifying whether the corresponding zone exists to the existing terminal and the newly connected terminal should be transmitted.

8 illustrates positions of dedicated channels for uplink short latency support according to an embodiment of the present invention.

Referring to FIG. 8, an uplink short latency zone is indicated through UL_MAP_IE of the first PUSC zone 900. The uplink short latency zone may be any one or more of a PUSC, an optional PUSC, and an AMC zone in FIG. 1B. In addition, a new subchannel configuration scheme may be applied. In addition, the SLDCCH is allocated in the corresponding region by designating the SLDCCH allocation information that provides the SLDDCH allocation and control information in the uplink short latency zone. In addition, the SLDCCH provides feedback channel information so that feedback on data provided in the short latency zone can be quickly transmitted.

9 is a flowchart illustrating a signal flow between a base station and a mobile station using an uplink short latency zone according to an embodiment of the present invention.

Referring to FIG. 9, the base station 900 designates location information of a short latency zone in UL-MAP_IE of the first PUSC zone (step 902). The base station 900 then provides location and modulation information of the SLDCCH (step 904). The base station 900 provides an SLDCCH at the location (step 906). The SLDCCH includes resource allocation information and data transmission information in the short latency zone in the uplink and location information of the SLDFCH in the downlink thereto.

The mobile station 950 receives the information from steps 902 to 906, and then performs transmission and processing of modulation and encoding on its own data in a manner specified by the SLDCCH (step 908), and transmits data at the assigned SLDDCH position. (Step 910).

The base station 900 decodes the signal received from the mobile station 950 (step 912) and transmits an error detection result to the SLDFCH designated by the SLDCCH (step 914). The base station 900 performs resource allocation by scheduling data transmission of the mobile station 950 according to an error detection result. In this case, the process may proceed to step 904 or 906 or 910 according to the resource allocation method. That is, when the resource allocation information is changed, the process moves to step 904 or 906. In step 904, the position and modulation information of the SLDCCH designating the information is also changed. In step 906, the position and modulation information of the SLDCCH is directly provided without changing the SLDCCH. Here, SLDCCH includes resource allocation information or data transmission information or feedback allocation information. According to circumstances, all three pieces of information are not changed and only partial information can be transmitted. In step 910, there is no change in resource allocation information and data transmission information as well as SLDCCH. That is, depending on whether an error is detected without additional control information, the mobile station transmits or retransmits the data using only the previously allocated area and transmission information.

10 is a view showing a frame structure consisting of a short latency zone according to the present invention.

Referring to FIG. 10, one short latency zone consists of nine OFDM symbols. Considering a TDD frame having a number of downlink symbols and a number of uplink symbols of 29:18, a downlink subframe includes one preamble symbol, three zones, and one midamble symbol. The uplink subframe consists of two zones. One zone of the uplink subframe may consist of three subzones. In this case, the zones may be configured as short latency zones according to circumstances. The midamble may be used as a MIMO midamble, a broadcast channel (BCH), a feedback channel, and the like according to circumstances.

Referring to FIG. 10, short latency zones are provided in a plurality of interlace structures according to a frame configuration scheme. Here, the interlace structure means a structure intertwined with each other, such as data transmission (retransmission) and feedback reception thereto or data reception (reception) and feedback transmission thereto.

Looking at interlace 1 in downlink data transmission, when using the first zone as a short latency zone, the base station transmits data in DL1 and receives a feedback signal from the mobile station in the first subzone of UL1. Similarly, looking at interlace 2, when using the second zone as a short latency zone, the base station transmits data in DL2 and receives a feedback signal from the mobile station in the first subzone of UL2. In interlace 3, when the third zone is used as a short latency zone, the base station transmits data in DL3 and receives a feedback signal from the mobile station in the third subzone of UL2. Depending on the situation, the base station may provide one to three short latency zones in one frame.

In addition, when looking at interlace 1 when transmitting uplink data, as a structure when UL1 is used as a short latency zone, the base station provides a SLDCCH in DL2 section and receives data in UL1 before UL1, and then in DL2 section of the next frame. Provides SLDFCH. Referring to the interlace 2, as a structure in which UL2 is used as a short latency zone, the base station provides a SLDCCH in a DL3 section before receiving UL2, receives data in UL2, and then provides a SLDFCH in a DL3 section of the next frame. Each interlace has a retransmission delay of 5ms.

In addition, the number of short latency zones is determined in one frame according to the TDD transmission rate and the allowable processing delay time. The base station determines whether to provide a short latency zone according to cell conditions, and configures one or more short latency zones to provide data transmission / reception to satisfy the short latency for the mobile station. When a number of short latency zones smaller than the maximum number of supported short latency zones is used, each zone may be configured to be adjacent or non-adjacent. Each interlace can be moved in the frame according to the support method. That is, when only a few zones are used, the position of the short latency zone and the channel may be shifted compared to a structure in which all of the supportable short latency zones are used.

The interlace configuration method, i.e., the position and size of the short latency zone / channel in the frame is determined according to the allowable processing delay and the TDD transmission rate.

As such, the proposed scheme can support short latency while being compatible with existing frame schemes, for example, the frame structure standardized in the WiMAX profile. In addition, the data burst transmission region may be configured with only a plurality of short latency zones under existing frame standards. That is, referring to FIG. 10, one frame may include a preamble, a plurality of downlink short latency zones, a midamble, and a plurality of uplink short latency zones.

11 is a flowchart illustrating a signal transmission and reception process of a mobile station according to an embodiment of the present invention.

Referring to FIG. 11, in step 1102, the mobile station acquires short latency zone information and proceeds to step 1104. The short latency zone information is information broadcasted by a base station through a broadcast channel at a predetermined periodic frame. In step 1104, the mobile station acquires the control information by using the obtained short latency zone information and proceeds to step 1106. The control information includes data burst allocation information of a downlink short latency zone or an uplink short latency zone corresponding thereto. The control information is transmitted to the mobile station on the SLDCCH. In step 1106, the mobile station determines whether the current zone section is a downlink short latency zone section. As a result of the determination, if it corresponds to the downlink short latency zone section, the process proceeds to step 1108, and if it corresponds to the uplink short latency zone section, the procedure proceeds to step 1114.

In step 1108, the mobile station receives data according to data burst allocation information and proceeds to step 1110. In step 1110, the mobile station generates a feedback signal according to whether data has been successfully received and decoded, and proceeds to step 1112. In step 1114, the mobile station generates data to be transmitted to the base station and proceeds to step 1112.

In step 1112, the mobile station transmits the data or feedback signal generated through the uplink short latency zone to the base station.

12 is a flowchart illustrating a signal transmission / reception process of a base station according to an embodiment of the present invention.

Referring to FIG. 12, in step 1202, the base station specifies a short latency zone and proceeds to step 1204. In step 1204, the base station determines whether the current frame period is a downlink short latency zone period. As a result of the determination, if the downlink short latency zone period proceeds to step 1206, and if the uplink short latency zone period proceeds to step 1208.

In step 1206, the base station transmits control information to the mobile station during the downlink short latency zone period and proceeds to step 1210. In step 1210, the base station transmits a feedback signal for data or previously received data to the mobile station during the downlink short latency zone period. In step 1208, the base station receives data or a feedback signal from the mobile station during the uplink short latency zone period.

In the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

1A and 1B illustrate a typical TDD-OFDMA frame structure and an OFDMA frame structure having multiple zones.

2 is a diagram illustrating a TDD-OFDMA frame structure for short latency support proposed in the present invention.

3A and 3B are diagrams illustrating data transmission and reception supporting short latency using a frame structure proposed by the present invention.

4 illustrates a TDD-OFDMA frame structure for supporting short latency in uplink proposed by the present invention.

5A and 5B illustrate data transmission and reception supporting short latency using a frame structure proposed by the present invention.

6 illustrates positions of dedicated channels for downlink short latency support according to an embodiment of the present invention.

7 is a signal flow diagram illustrating operation between a base station and a mobile station using a downlink short latency zone according to an embodiment of the present invention.

8 illustrates positions of dedicated channels for uplink short latency support according to an embodiment of the present invention.

9 is a flowchart illustrating a signal flow between a base station and a mobile station using an uplink short latency zone according to an embodiment of the present invention.

10 illustrates a frame structure composed of short latency zones according to an embodiment of the present invention.

11 is a flowchart illustrating a signal transmission / reception process of a mobile station according to an embodiment of the present invention.

12 is a flowchart illustrating a signal transmission / reception process of a base station according to an embodiment of the present invention.

Claims (30)

In the mobile communication system, in the downlink signal transmission method of the base station, In a frame including a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, the second region is located in each of a downlink subframe and an uplink subframe, wherein the downlink subframe and The first specific region and the second specific region are preset in the uplink subframe, The base station indicating a first specific region of a downlink subframe of the second region through the first region; Indicating, through the first specific region, the second specific region for receiving information on a dedicated channel to which data is transmitted or retransmitted within the first specific region and a feedback signal for the data; Transmitting or retransmitting data through a dedicated channel indicated through the first specific region; And transmitting a feedback signal through the second specific region. The method of claim 1, The first specific region indication of the downlink subframe of the second region through the first region uses a MAP Information Element (IE) message. The method of claim 2, The MAP IE message includes at least one of resource allocation mode information, resource region to which data is transmitted, feedback channel allocation information, modulation and coding scheme information. The method of claim 1, And the areas are areas determined by time and frequency resources. The method of claim 1, In the first specific region, the base station receives the resource allocation information and encodes the time before data is transmitted, the mobile station demodulates and decodes the received data, and encodes a feedback message (ACK / NACK) according to whether or not an error is detected. Receiving the time and error detection message of the base station, performing scheduling, and encoding the data to determine the downlink signal transmission method of the base station. The method of claim 1, And the second specific region is determined in consideration of the time taken for downlink signal reception processing of the mobile station from the first specific region. In the mobile communication system, in the uplink signal transmission method of the mobile station, In a frame including a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, the second region is located in each of a downlink subframe and an uplink subframe, wherein the downlink subframe and The first specific region and the second specific region are preset in the uplink subframe, Receiving, by the mobile station, a first specific region of a downlink subframe and a second specific region of an uplink subframe of the second region through the first region of a current frame; Receiving, through the first specific region, a first specific region of a next frame that receives information on a dedicated channel through which data is transmitted or retransmitted in the second specific region and a feedback signal for the data; Transmitting or retransmitting data through a dedicated channel indicated through the first specific region; And receiving a feedback signal through a first specific region of the next frame. The method of claim 7, wherein The first specific region indication of the downlink subframe of the second region through the first region is performed by using a MAP Information Element (IE) message. The method of claim 8, The MAP IE message includes at least one of resource allocation mode information, resource region to which data is transmitted, feedback channel allocation information, modulation and coding scheme information. The method of claim 7, wherein And the areas are areas determined by time and frequency resources. The method of claim 7, wherein The first specific region is determined in consideration of the time taken by the base station to receive the uplink signal of the mobile station and transmit a feedback signal thereto from the end of the second specific region of the previous frame. Signal transmission method. The method of claim 7, wherein And determining the processing time from the end of the first specific region of the current frame to the time for transmitting the uplink signal by the mobile station. In a mobile communication system, a method for receiving a downlink signal of a mobile station, In a frame including a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, the second region is located in each of a downlink subframe and an uplink subframe, and the downlink subframe The first specific region and the second specific region are preset in the uplink subframe. Receiving, by the mobile station, a first specific region of a downlink subframe of the second region through the first region; Receiving, via the first specific region, the second specific region for receiving information on the dedicated channel through which data is transmitted or retransmitted in the first specific region and the feedback signal for the data; Receiving or re-receiving data through a dedicated channel indicated through the first specific region; And transmitting a feedback signal through the second specific region. The method of claim 13, The first specific region indication of the downlink subframe of the second region through the first region is performed by receiving a MAP Information Element (IE) message. The method of claim 14, The MAP IE message includes at least one of resource allocation mode information, resource region to which data is transmitted, feedback channel allocation information, modulation and coding scheme information. The method of claim 13, And the areas are areas determined by time and frequency resources. The method of claim 13, The first specific region is determined in consideration of the time taken for the downlink signal reception process, the time taken for the feedback signal transmission of the mobile station, and the time taken for the downlink signal transmission process of the base station. How to receive the signal. The method of claim 13, And the second specific region is determined in consideration of the time taken by the mobile station for downlink signal reception processing from the end of the first specific region. In the mobile communication system, in the uplink signal receiving method of the base station, In a frame including a first region in which frame control information is transmitted and a second region in which a data burst is transmitted, the second region is located in each of a downlink subframe and an uplink subframe, wherein the downlink subframe and The first specific region and the second specific region are preset in the uplink subframe, The mobile station indicating a first specific region of a downlink subframe and a second specific region of an uplink subframe of the second region through the first region of a current frame; Instructing, through the first specific region, a first specific region of a next frame for transmitting information about a dedicated channel to which data is transmitted or retransmitted in the second specific region and a feedback signal for the data; Receiving or re-receiving data through a dedicated channel indicated through the first specific region; And transmitting a feedback signal through a first specific region of the next frame. The method of claim 19, The first specific region indication of the downlink subframe of the second region through the first region is performed by using a MAP Information Element (IE) message. The method of claim 20, The MAP IE message includes at least one of resource allocation mode information, resource region to which data is transmitted, feedback channel allocation information, modulation and coding scheme information. The method of claim 19, And the areas are areas determined by time and frequency resources. The method of claim 19, The first specific region is determined in consideration of the time taken by the base station to receive the uplink signal of the mobile station and transmit a feedback signal thereto from the end of the second specific region of the previous frame. How to receive the signal. The method of claim 19, And the second specific region is determined in consideration of the processing time from the end of the first specific region of the current frame until the mobile station transmits an uplink signal. In the mobile communication system, in the signal transmission and reception method of the base station, The frame includes a downlink subframe and an uplink subframe, and a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe. Instructing the mobile station through the first specific region the second specific region for receiving information on a dedicated channel to which data is transmitted or retransmitted and a feedback signal for the data; Transmitting or retransmitting data through a dedicated channel indicated through the first specific region; And transmitting and receiving a feedback signal through the second specific region. The method of claim 25, And the first specific area and the second specific area are areas determined by time and frequency resources. The method of claim 25, The first specific region is determined in consideration of the time taken by the base station to receive the uplink signal of the mobile station and transmit a feedback signal thereto from the end of the second specific region of the previous frame. Way. The method of claim 25, And the second specific region is determined in consideration of the processing time from the end of the first specific region of the current frame until the mobile station transmits an uplink signal. In a mobile communication system, in a signal transmission and reception method of a mobile station, The frame includes a downlink subframe and an uplink subframe, and a first specific region and a second specific region are preset in the downlink subframe and the uplink subframe. Receiving, by the base station, the second specific region for receiving information on the dedicated channel to which data is transmitted or retransmitted and the feedback signal for the data from the base station; Receiving or re-receiving data through a dedicated channel indicated through the first specific region; And transmitting a feedback signal through the second specific region. The method of claim 29, And the first specific area and the second specific area are areas determined by time and frequency resources.

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