KR20080021347A - Apparatus and method for receiving a complex retransmission burst in a mobile communication system - Google Patents

Abstract

The present invention relates to a receiving apparatus and a method for minimizing a reception error of a hybrid automatic repeat request (HARQ) burst in a mobile communication system, and for receiving a hybrid automatic repeat request (HARQ) burst in a mobile communication system. An apparatus, comprising: a decoder for decoding a map including information for decoding bursts received from a transmitter and HARQ burst control information, and comparing the received HARQ burst control information with previously received HARQ burst control information. A control unit for determining whether a burst is a retransmission HARQ burst, a combiner combining the received burst with a previously received burst in the case of the retransmission HARQ burst, a decoding discriminator for decoding the combined burst and determining a decoding result; , And a memory for storing the HARQ burst control information and the decoding result.

Accordingly, the present invention can prevent a reception error of a new burst or a retransmission HARQ burst due to the MAP reception impossibility and the distortion of the ACK / NAK information that may occur due to the influence of the channel.

Description

Apparatus and method for receiving a complex retransmission burst in a mobile communication system {APPARATUS AND METHOD FOR RECEIVING HYBRID AUTOMATIC REPEAT REQUEST BURST IN MOBILE COMMUNICATION SYSTEM}

1 is a view schematically showing the configuration of a conventional IEEE 802.16e based OFDMA system,

2 is a view showing the configuration of a data frame in a conventional IEEE 802.16e based OFDMA system,

3A to 3D are diagrams illustrating a normal transmission process of a HARQ burst;

4A to 4E are views illustrating a case where a reception error of a HARQ burst occurs;

5 is a block diagram showing a configuration of an apparatus for receiving a HARQ burst according to an embodiment of the present invention;

6 is a flowchart illustrating a method of receiving a HARQ burst according to an embodiment of the present invention.

The present invention relates to a data receiving apparatus and method in a mobile communication system, and more particularly, to a receiving apparatus and method capable of minimizing a reception error of a hybrid automatic repeat request (HARQ) burst in a mobile communication system.

Existing wireless communication networks have been developed mainly for voice services, which have disadvantages of relatively small data transmission bandwidth and high usage fee. In order to solve these drawbacks, research on an orthogonal frequency division multiplexing (WDM) method for providing broadband packet data service is rapidly progressing. In general, a wireless local area network (WLAN) has a short reach, and thus, a performance decreases when a terminal is moving or moves away from an access point (AP). In addition, the wireless Internet based on the third generation mobile communication system has a disadvantage that the price is expensive.

Meanwhile, an orthogonal frequency division multiple access system (OFDMA), which is strong in multipath fading as a transmission method, is an IEEE 802.16 mobile Internet standard that is a representative example of a mobile communication system that provides packet data service. The WiBro system is based on e. WiBro service is a service that allows you to use high-speed Internet while moving anywhere anytime like a mobile phone. It is a service that uses the frequency band of and includes Internet speed (ie service bandwidth) of about 1Mbps.

In addition, in the mobile communication system providing the packet data service, the mobile terminal receiving the packet from the base station informs the base station whether the packet is successfully received, and the base station retransmits the packet that the mobile terminal did not normally receive for stable packet transmission. HARQ technology is becoming common.

Hereinafter, a method of receiving a HARQ burst in a conventional IEEE 802.16e based OFDMA system will be described with reference to the accompanying drawings.

First, FIG. 1 is a diagram schematically illustrating a configuration of a general IEEE 802.16e based OFDMA system.

The IEEE 802.16e based OFDMA system shown in FIG. 1 includes a mobile station (MS) 101, a base station BS 102, a base station controller 105, and authentication. A server Authentication, Authorization and Accounting server (hereinafter referred to as AAA server) 107 and a home agent (hereinafter referred to as HA) 109 are included. The MS 101 is a terminal used by a subscriber to receive a portable Internet service. The BS 103 communicates with the MS 101 via a wireless interface at a wired network end. The base station controller 105 is an access router that controls the MS 101 and the BS 103 and routes Internet Protocol (IP) packets. The AAA server 117 permits access to the portable Internet only for legitimate users, and performs authentication, authority verification, and charging for users and devices in order to provide portable Internet services. The HA 109 also supports IP mobility of the MS 101 in a home network. The operator IP network 111 connects the base station controller 105 to the AAA server 107 to the HA 109 and the public IP network 113.

2 is a diagram showing the configuration of a data frame in a typical IEEE 802.16e based OFDMA system.

In FIG. 2, the horizontal axis represents a time axis in OFDMA symbol units, and the vertical axis represents a frequency axis in subchannel units. The subchannel means a bundle of a plurality of subcarriers allocated to each user. Specifically, in the OFDMA physical layer, a plurality of subcarriers are divided into groups, and at least one subcarrier selected for each group is allocated to different users for data transmission. In this case, subcarriers constituting each subchannel may be adjacent to each other or spaced at equal intervals.

Slots assigned to each user are defined by data regions in two-dimensional space, as shown in FIG. 2, which is a set of consecutive subchannels allocated by bursts. The data area may be allocated to an uplink (UL) of a specific user or a BS may transmit the data area to a specific user in downlink (DL).

In FIG. 2, the first symbol of the DL subframe is a preamble. The MS uses synchronization acquisition, base station ID acquisition, and channel estimation included in the preamble. Since the ID of the BS is used as a value for scrambling and subcarrier permutation, it is necessary to acquire the ID of the BS in order to decode the DL burst received by the MS. A frame control header (FCH) is located after the preamble. The FCH includes information (DL-MAP length, coding method, etc.) necessary for DL-MAP decoding.

In addition, the data frame of FIG. 2 defines a structure of the entire frame through a DL-MAP message and a UL-MAP message in a broadcast form that define positions and uses of bursts allocated to DL and UL. The information element constituting the DL-MAP (hereinafter referred to as "DL-MAP IE (Information Element)") includes a Down Interval Usage Code (Down Interval Usage Code), a CID (Connection ID), and location information of a DL burst (subchannel offset, Symbol transmission, number of subchannels, number of symbols) UL transmission starts from a control symbol, and IE (hereinafter, “UL-MAP IE”) constituting the UL-MAP message includes UIUC (Up) for each CID. Interval Usage Code) and Duration. Here, the use of each section is determined according to the UIUC value used in the UL-MAP, and each section starts at a point separated by the duration defined by the UL-MAP IE from the start point of the previous UL-MAP IE. Therefore, in the IEEE 802.16e-based OFDMA system, the WiBro terminal measures the preamble received from the DL, decodes the FCH burst, and then performs DL-MAP decoding by using the DL-MAP IE and receives the data by decoding the general data burst. The process will proceed.

Meanwhile, the IEEE 802.16e-based OFDMA system selectively supports the HARQ scheme to have error correction capability against channel state and interference change. The HARQ scheme improves performance due to a signal to noise (SNR) gain and a time diversity effect caused by combining a received error packet with a retransmitted packet. In the IEEE 802.16e based OFDMA system, parameters required between the MS and the BS are exchanged in an initialization step to operate an HARQ operation. Thereafter, in order to allocate a burst for HARQ transmission (hereinafter, referred to as HARQ burst), DL-MAP or Sub-MAP (Sub-MAP is a MAP which is operated separately to allocate HARQ. Assign the UL-MAP IE. The DL / UL-MAP IE includes information on a region to which a burst is allocated and HARQ sub-burst IE information for each coding scheme applied to each HARQ type. Each HARQ sub-burst IE includes each HARQ burst control information and information for HARQ operation. HARQ may be operated in DL / UL, respectively, and transmits a burst from BS to MS or MS to BS in each case. Hereinafter, in the present specification, the HARQ operation and control method will be described using the case of DL as an example.

In addition, two types of HARQ schemes are proposed in an IEEE 802.16e-based OFDMA system. In the HARQ scheme, a Chase Combining scheme in which a HARQ burst identical to a previously transmitted burst is retransmitted to obtain a combined gain, and a redundant component of the previously transmitted burst may be retransmitted to obtain a combined gain and a coding gain. An IR (Incremental Redundancy) scheme is differently assigned to the HARQ Chase / IR sub-burst IE according to each HARQ scheme.

In the HARQ method, the chase combining method may include concatenating one or more MAC Protocol Data Units (PDUs) for burst transmission when a new burst transmission or retransmission is performed, and by adding a 16-bit Cyclic Redundancy Check (CRC) to the concatenated result A HARQ Encoder Packet (hereinafter referred to as "HEP") is formed. The MS attempts to decode the HEP during the first burst transmission, and decodes the CRC 16 bits in the decoding process to determine whether the decoding succeeds or fails. Whether the decoding succeeds or fails is indicated by an ACK or a negative acknowledgment (NAK) signal in an ACK (ACK) signal region (ACK). Therefore, if the decoding process is successful, the MS transmits an ACK on the UL ACK channel allocated by the BS. However, if the decoding process fails, the MS transmits a NAK to the ACK signal region of the UL allocated by the BS, and the BS receiving the NAK retransmits the same HARQ burst. The BS can repeat the HARQ until the MS successfully decodes the HEP and delivers an ACK to the BS. As described above, the chase combining HARQ scheme determines whether to retransmit based on the ACK or NAK signal transmitted from the MS to the BS according to the success of the decoding process. However, an error of determining a new burst or retransmission HARQ burst due to MAP reception failure or distortion of ACK / NAK information that may occur due to channel influence may occur. In addition, when judging a new or retransmission incorrectly as a retransmission HARQ burst, the MS transmits a NAK by combining different information, and the BS receiving the NAK continues the HARQ burst different from the original HARQ burst to be transmitted. Retransmissions may occur, resulting in lower overall throughput. Therefore, there is a need for a method of preventing HARQ malfunction due to channel conditions by increasing the accuracy of determining a new burst or a retransmission HARQ burst.

The present invention provides a receiving apparatus and method capable of preventing a reception error of a retransmission HARQ burst in a mobile communication system.

Accordingly, the present invention provides an apparatus for receiving a HARQ burst in a mobile communication system, comprising: a decoder for decoding a map including information for decoding a burst received from a transmitter and HARQ burst control information; A control unit for determining whether the received burst is a retransmission HARQ burst by comparing the received HARQ burst control information with previously received HARQ burst control information; and in the case of the retransmission HARQ burst, the received burst and the previously received burst A combiner for combining, a decoding discriminator for decoding the combined burst and determining a decoding result; And a memory for storing the HARQ burst control information and the decoding result.

In addition, the present invention provides a method for receiving a HARQ (Hybrid Automatic Repeat Request) burst in a mobile communication system, a decoding process for decoding a map including information for decoding the burst received from the transmitter and HARQ burst control information, A control process of determining whether the received burst is a retransmission HARQ burst by comparing the received HARQ burst control information with previously received HARQ burst control information; and in the case of the retransmission HARQ burst, the received burst and the previously received A combining process of combining the bursts, and a decoding determination process of decoding the combined bursts to determine a decoding result.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intention or custom of a user or an operator. Therefore, the definition should be made based on the contents throughout the specification.

Hereinafter, an embodiment of the present invention will be described using an OFDMA system that transmits MAP information for transmission and reception of a UL / DL burst. However, the system to which the present invention is applied is not limited to the OFDMA system. That is, the present invention supports HARQ and may be applied to various mobile communication systems for transmitting and receiving the MAP information or the equivalent information when transmitting and receiving UL / DL bursts.

First, Table 1 below shows a HARQ burst control information field for transmitting HARQ bursts in the HARQ scheme using the chase combining.

The HARQ burst control information includes a HARQ Identifier Sequence Number (AI_SN), a Down Interval Usage Code (DIUC), a HARQ Channel Identifier (ACID), and the like. The HARQ identifier serial number is a value that toggles from '0' to '1' or '1' to '0' every time a new burst is received in the HARQ channel, indicating a new HEP transmission after the transmission of the HEP. For example, when the BS transmits a new burst to the MS, the BS toggles the HARQ identifier serial number from the previous value and transmits the HARQ identifier serial number to the same value as the previous value when transmitting the retransmitted HARQ burst. . Therefore, when the MS detects a change in the HARQ identifier serial number value, the MS recognizes that it has received a new burst, that is, a new HEP from the BS.

Meanwhile, the HARQ transmission scheme basically operates as a SAW (Stop And Wait) protocol. The DSD message transmitted aperiodically from the BS includes a HARQ DL ACK delay offset parameter.After receiving a successful HEP, the MS sends a ACK to the BS as a response after a delay of the HARQ DL ACK delay offset parameter value. Send ACK. However, unlike ACK transmission, the retransmission time of the HEP is not fixed. In the DL, the BS transmits a DL-MAP IE to the MS, and the MS transmits ACK / NAK information on the UL ACK channel allocated by the BS. The HARQ transmission scheme supports a plurality of HARQ channels for one connection. How many HARQ channels are used is determined by the BS. These HARQ channels can be distinguished from each other by the HARQ Channel IDentifier of Table 1.

Accordingly, the MS determines whether the burst is a retransmission burst or a new burst using the HARQ burst control information.

Hereinafter, a reception operation of the HARQ burst will be divided into a case where HARQ burst is normally received (FIGS. 3A to 3D) and a reception error of HARQ burst (FIGS. 4A to 4E). .

3A to 3D are diagrams illustrating a normal reception process of a HARQ burst.

In FIG. 3A, the MS receives the DL burst A from the BS and AI_SN (0) included in the HARQ burst control information, and transmits a DL burst decoding result ACK to the ACK channel of the UL allocated by the BS. Upon receiving the ACK, the BS transmits the next DL burst B and AI_SN (1) included in the HARQ burst control information to the MS.

In FIG. 3B, the MS receives the DL burst A from the BS and AI_SN (0) included in the HARQ burst control information, and transmits a DL burst decoding result ACK to the ACK channel of the UL allocated by the BS. And when the MS does not receive the newly transmitted DL burst (B) and the AI_SN (1) included in the HARQ burst control information, the BS waits for the HARQ burst (B ') and HARQ of the DL burst (B) to the MS The AI_SN (1) included in the burst control information is retransmitted. At this time, since the AI_SN is toggled with respect to the DL burst A, the MS can recognize the HARQ burst B 'as a new burst.

In FIG. 3C, when the MS receives the AI burst (A) and the AI_SN (0) included in the HARQ burst control information from the BS and transmits the DL burst decoding result NAK on the ACK channel of the UL allocated by the BS, the MS receives the NAK. The received BS retransmits the same HARQ burst A 'as the DL burst A and the AI_SN (0) not toggled. Therefore, the MS can normally combine the DL burst A and the HARQ burst A 'that were initially received.

In FIG. 3D, the MS receives the DL burst A and AI_SN (0) from the BS and transmits the DL burst decoding result NAK on the UL ACK channel. Upon receiving the NAK, the BS retransmits the HARQ burst A 'and AI_SN (0). However, when the BS waits because the MS has not received the retransmitted HARQ burst A 'and AI_SN (0), the BS retransmits the second HARQ burst A and AI_SN (0).

In the normal HARQ burst reception process described with reference to FIGS. 3A to 3D, the MS determines whether a new burst or a HARQ burst is retransmitted based on whether to toggle AI_SN upon MAP reception. However, as described above, when the MS determines only a new burst or HARQ burst by checking whether AI_SN is toggled when receiving MAP, problems such as MAP reception error and distortion of ACK / NAK information occur, such that HARQ as shown in FIGS. 4A to 4E below. Burst reception errors may occur.

4A to 4E are diagrams illustrating a case where a reception error of a HARQ burst occurs.

In FIG. 4A, the MS receives DL burst A and AI_SN (0) from the BS, and although the NAK is transmitted through the UL ACK channel, an error occurs in the UL ACK channel and the BS incorrectly receives the NAK as an ACK. In this case, an error occurs in which the MS cannot receive the burst A again.

In FIG. 4B, the MS receives the DL burst A and AI_SN (0) from the BS and transmits a NAK on an AC channel of the UL. After receiving the NAK, the BS retransmitted the HARQ burst (A ') and AI_SN (0), but the MS did not receive the retransmitted information and thus the BS did not receive the information on the ACK channel of the UL. If it is determined that the BS transmits a new DL burst (B) and AI_SN (1) to the MS, a reception error of the HARQ burst (A ') occurs.

4A and 4B, the UE does not receive the retransmitted HARQ burst and receives the next new burst. However, the UE waiting for the retransmission HARQ burst may determine the initial transmission burst through the AI_SN information, thereby controlling the receiver HARQ. There is no problem with the operation. However, a request for retransmission may be made through higher layer ARQ for the failure of receiving the HARQ burst to be retransmitted.

In FIG. 4C, when the MS receives the DL burst A and the AI_SN (0) from the BS and transmits an ACK on the UL ACK channel, but an error occurs and the BS determines that the NAK is the BS, the BS determines the HARQ burst A '. Resend AI_SN (0) back to the MS. Upon receipt of this, the MS performs an unnecessary operation (for example, combining) with respect to the HARQ burst already determined as ACK.

In FIG. 4D, the MS receives the DL burst A and AI_SN (0) from the BS, transmits an ACK on the UL ACK channel, and the BS normally receives the new DL burst A and toggles the AI_SN (1). Sent. However, if the MS does not receive the DL burst (B) and AI_SN (1) and transmits information on the ACK channel of the UL, but the BS determines that it is an ACK, the BS will send a new DL burst (C) to the MS. Since AI_SN (0) is transmitted, the decoding process of the HARQ burst fails. In this case, since the MS_SN is not toggled, the MS may misinterpret the new DL burst C as the HARQ burst A 'and perform a combination with the previously received DL burst A.

In FIG. 4E, when the MS receives the DL burst A and the AI_SN (0) from the BS and transmits the decoding result NAK on the UL ACK channel, but the BS determines that the ACK is the BS, the BS receives a new DL burst (B) and AI_SN ( Send 1). However, if the BS does not receive the DL burst (B) and AI_SN (1) and the BS receives the ACK despite the information transmitted on the UL ACK channel, the BS receives a new DL burst (C) and AI_SN (0). ). In this case, since the AI_SN is not toggled, the MS may make an error of combining the new DL burst C with the DL burst A having a reception error.

Therefore, in FIG. 4C to FIG. 4E, the AI_SN is not toggled from the MS's point of view, but an actual BS generates an error of transmitting a new DL burst. Therefore, a method for accurately distinguishing a new DL burst from a retransmitted HARQ burst is required.

Hereinafter, a method for determining the new burst or retransmission HARQ burst according to an embodiment of the present invention will be described with reference to the accompanying drawings.

5 is a block diagram illustrating a configuration of an apparatus for receiving a HARQ burst according to an embodiment of the present invention.

The receiving device of FIG. 5 includes a transceiver 501, a MAP decoder 503, a controller 505, a memory 507, a combiner 509, a forward error correction (FEC) decoder 511, and a CRC. Discriminator 513 is included.

The transceiver 501 transmits and receives various control data (MAP, ACK, NACK, etc.) and UL / DL frames communicated between the BS and the MS under the control of the controller 503. When the MAP decoder 503 receives the DL frame under the control of the controller 503, the MAP decoder 503 decodes the DL-MAP information including the HARQ control information as well as information for decoding the DL burst in the DL frame ( Interpret). In the present invention, the control unit 503 determines whether the received DL burst is a new burst or a retransmission HARQ burst by using AI_SN, DIUC, duration, or repetition information among the parameters included in the HARQ control information. .

In an embodiment of the present invention, the control unit 505 includes a first comparator 505-1, a second comparator 505-2, and a third comparator 505-3, and includes the first to third comparators ( 505-1, 505-2, and 505-3 perform HARQ burst determination operation for preventing a reception error state of the HARQ burst illustrated in FIGS. 4C to 4E by using the parameters of the HARQ control information.

First, the first comparator 505-1 checks whether the AI_SN is toggled and determines whether the currently received DL burst is a new burst or a HARQ burst to be retransmitted. If the AI_SN is not toggled, the second comparator 505-2 determines the state of FIGS. 4C to 4E. When the reception error occurs because AI_SN is not toggled as shown in FIGS. 4C to 4D, the second comparator 505-2 moves according to the FEC code type to prevent a combination of a new DL burst and another burst previously received. If the parameter value is the same by comparing the DIUC, Duration information, or DIUC, duration, and repeating information among the HARQ control information of the burst and the HARQ control information of the current burst, it is determined whether the previous burst decoding result is ACK, and the parameter value is different. In this case, control is performed so that the old burst and the new burst are not combined.

The third comparator 505-3 determines that the decoding result of the previous burst is ACK or NAK when the parameter value comparison result is the same, and determines that the decoding result is the state of FIG. 4C. In this case, the MS normally receives the previous burst and transmits an ACK to the BS. However, if the BS recognizes the NACK as a transmission error or the like, the BS retransmits the same HARQ burst as the previous burst to the MS. Accordingly, the third comparator 505-3 controls not to perform the combination of the DL burst and the HARQ burst already received normally, and also controls the transceiver 501 to transmit the ACK back to the BS. In the present invention, such an ACK is defined as an artificial ACK. On the other hand, if the decoding result of the previous burst is NAK, the third comparator 505-3 controls to combine the previous burst and the retransmitted HARQ burst.

According to an embodiment of the present invention, the memory 507 stores the HARQ burst transmission information (DIUC, duration, repeatation, AI_SN) and the decoding result (ACK or NACK). The combiner 509 combines the previously received burst with the retransmitted HARQ burst when the controller 505 determines that the received burst is a HARQ burst to be retransmitted. The FEC decoder 511 decodes the received burst for data error correction. The CRC discriminator 213 determines the ACK or NACK of the received burst according to whether the decoding of the received burst is successful.

Accordingly, the present invention compares the HARQ control information of the currently received burst with the HARQ control information of the previous received burst according to the above procedure to determine a new burst or a retransmission HARQ burst, thereby increasing the accuracy of determining a new burst or HARQ burst. Can be.

6 is a flowchart illustrating a method of receiving a HARQ burst according to an embodiment of the present invention.

Before describing the method of FIG. 6, the present invention assumes the following conditions. In the IEEE 802.16e-based OFDMA standard, in case of a chase HARQ, the BS receives a NAK, and then the profile of the HARQ burst to be retransmitted must be the same, and the boosting and the repetition level may be different. The retransmission HARQ burst profile specified in the specification means the FEC code type mapped to the DIUC value, and the fact that the repetition level may be different means that the duration value may also be different. The duration value also means the number of subchannels allocated to the MS, which is calculated as the number of subchannels (number of symbols / 2) transmitted through the MAP. When the MS performs recombination of HARQ bursts, the coupling unit is a concatenated block and the concatenated law is determined by the number of subchannels allocated to the DIUC and the MS.

However, when the FEC code type is Quadrature Phase Shift Keying (QPSK), the number of subchannels allocated to the MS means the number of subchannels from which a repetition component is excluded. In the case of the replicated HARQ burst, the MS performs slot combining, thereby removing the repetition component. For example, if the duration of the HARQ burst control information is '10' and the repetition is '2', the number of subchannels applied to the actual connection law is '5' (that is, duration / repetition: size below) Therefore, when considering the HARQ burst combination, the size of the new burst and the size of the retransmitted HARQ burst must be the same for the combined block unit to be combined.

Referring to the method of FIG. 6 under the above assumption, in step 601, when the MAP decoder 503 receives a DL frame under the control of the controller 503, information for decoding the DL burst in the DL frame is of course. In step 603, the DL-MAP information including the HARQ control information is decoded (interpreted). In step 603, the first comparator 505-1 checks whether the AI_SN is toggled and determines whether the currently received DL burst is a new burst or a HARQ burst to be retransmitted. If AI_SN is toggled in step 603, the first comparator 505-1 determines a new burst and proceeds to step 617, and if not, determines that it is a retransmission HARQ burst and proceeds to step 605. In step 605, if AI_SN is not toggled in step 603, the second comparator 505-2 determines that the state of FIGS. 4C to 4E is performed, and proceeds to step 605. In step 605, the second comparator 505-2 determines whether the FEC code type is QPSK. The reason for determining whether it is QPSK in step 605 is that only the QPSK includes DIUC, duration, and repetition in HARQ burst control information, and in case of 16QAM or 64QAM, only DIUC and duration are included in HARQ burst control information. . Therefore, if the FEC code type is QPSK in step 605, the process proceeds to step 607, and in step 609 if the FEC code type is not QPSK.

If it is not the QPSK in step 605, in step 609, the second comparator 505-2 compares the DIUC and the duration information among the HARQ control information of the previous burst and the HARQ control information of the current burst and retransmits when the parameter value is the same. If the parameter value is different, it is determined as a new burst and the process proceeds to step 617. Meanwhile, in the case of 16QAM or 64QAM, the size does not exist and the size has the same meaning as the duration. Therefore, in step 605, if it is not the QPSK, it is also possible to perform step 607 instead of step 609.

On the other hand, in the case of the QPSK, the second comparator 505-2 in step 607 compares the size of the DIUC and the size information of the HARQ control information of the previous burst and the HARQ control information of the current burst to be retransmitted when the parameter value is the same. If it is determined, the process proceeds to step 611. If the parameter value is different, the process proceeds to step 617.

In step 611, if the parameter value comparison result is equal to the parameter value, the third comparator 505-3 checks whether the decoding result of the previous burst is ACK or NAK. If it is not the ACK, it is determined as a retransmission burst and proceeds to step 615. In operation 613, the third comparator 505-3 controls not to perform the combination of the DL burst and the HARQ burst already received normally, and also controls the transceiver 501 to transmit an artificial ACK. On the contrary, if it is determined as a new burst in step 611, the third comparator 505-3 controls not to combine the previous burst with the new burst, and proceeds to step 617. Accordingly, in step 617, the FEC decoder 511 decodes the received burst to correct the data error, and proceeds to step 619. In step 619, the CRC discriminator 213 determines the ACK or NACK of burst reception according to whether the received burst has been successfully decoded, and stores the result in the memory 507. In step 621, the transceiver 501 Under the control of the control unit 503, transmits the ACK or NACK to the BS.

Meanwhile, in the embodiment of the present invention, after performing the process of comparing the duration between the HARQ control information of the previous burst and the HARQ control information of the current burst with the duration of the previous burst in steps 607 and 607, it is determined whether it is QPSK. It is also possible to determine the size information only in the case of QPSK.

Therefore, the present invention compares the received HARQ burst transmission information with the previously received HARQ burst transmission information to determine a new burst or retransmission HARQ burst, so that MAP reception that may occur due to the influence of the channel as shown in FIGS. 4C to 4E is impossible, and Determination of a new burst or retransmission HARQ burst due to distortion of ACK / NAK information can be compensated for.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made 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 determined not only by the scope of the following claims, but also by the equivalents of the claims.

The present invention can prevent a reception error of a new burst or a retransmission HARQ burst due to the MAP reception impossibility and the distortion of the ACK / NAK information that may occur due to the influence of the channel.

In addition, the present invention can prevent HARQ malfunction due to channel conditions by increasing the accuracy of determining a new burst or a retransmission burst.

Claims (16)

An apparatus for receiving a hybrid automatic repeat request (HARQ) burst in a mobile communication system, A decoder for decoding a map including information for decoding bursts received from a transmitter and HARQ burst control information; A controller for comparing the received HARQ burst control information with previously received HARQ burst control information to determine whether the received burst is a retransmission HARQ burst; A combiner for combining the received burst with the previously received burst in case of retransmission HARQ burst as a result of the determination; A decoding discriminator for decoding the combined burst to determine a decoding result; And a memory for storing the HARQ burst control information and the decoding result. The method of claim 1, The HARQ burst control information is And an uplink / downlink section use code and a duration and HARQ identifier serial number information. The method of claim 1, The HARQ burst control information is Receiving device further comprises a repetition information. The method according to claim 1 or 2, The control unit A first comparator determining whether the received burst is a retransmission HARQ burst by checking whether the HARQ identifier serial number value is toggled; If the HARQ identifier serial number is not toggled, comparing the received HARQ burst control information with the previously received HARQ burst control information according to an FEC code type and determining the received burst as a retransmission burst when the HARQ identifier serial number value is the same; And a receiver comprising two comparators. The method of claim 4, wherein If it is determined that the retransmission burst in the second comparator, And a third comparator for determining a decoding result of the previously received burst. The method of claim 4, wherein The second comparator When the FEC code type is QPSK, the received HARQ burst control information and the previously received HARQ burst control information are compared with the downlink segment use code and duration and repetition information. Receiving device characterized in that determined by the HARQ burst. The method of claim 4, wherein The second comparator When the FEC code type is not QPSK, the received HARQ burst control information and the previously received HARQ burst control information are compared with the downlink segment use code and duration information, and if the same, the received burst is converted into the retransmitted HARQ burst. Receiving device, characterized in that determined. The method of claim 5, wherein The third comparator If the decoding result of the previously received burst is ACK, control to send an artificial ACK to the transmitter and control the operation of the combiner such that the previously received burst and the currently received burst are not combined. Device. In the method for receiving a HARQ (Hybrid Automatic Repeat Request) burst in a mobile communication system, A decoding process of decoding a map including information for decoding a burst received from a transmitter and HARQ burst control information; A control process of comparing the received HARQ burst control information with previously received HARQ burst control information to determine whether the received burst is a retransmission HARQ burst; A combination process of combining the received burst with a previously received burst in case of retransmission HARQ burst as a result of the determination; And a decoding determination process of determining a decoding result by decoding the combined burst. The method of claim 9, The HARQ burst control information is And an uplink / downlink interval use code and a duration and HARQ identifier serial number information. The method of claim 9, The HARQ burst control information is Receiving method further comprises a repetition information. The method according to claim 9 or 10, The control process A first comparison process of determining whether the received burst is a retransmission HARQ burst by checking whether the HARQ identifier serial number value is toggled; If the HARQ identifier serial number is not toggled, comparing the received HARQ burst control information with the previously received HARQ burst control information according to an FEC code type and determining the received burst as a retransmission burst when the HARQ identifier serial number value is the same; Receiving method comprising a comparison process. The method of claim 12, If it is determined that the retransmission burst in the second comparison process, And a third comparison process of determining a decoding result of the previously received burst. The method of claim 12, The second comparison process is When the FEC code type is QPSK, the received HARQ burst control information and the previously received HARQ burst control information are compared with the downlink segment use code and duration and repetition information. Receiving method characterized in that the HARQ burst. The method of claim 12, The second comparison process is When the FEC code type is not QPSK, the received HARQ burst control information and the previously received HARQ burst control information are compared with the downlink segment use code and duration information, and if the same, the received burst is converted into the retransmitted HARQ burst. Receiving method, characterized in that judging. The method of claim 13, The third comparison process is If the decoding result of the previously received burst is ACK, control to send an artificial ACK to the transmitter and control the operation of the combiner such that the previously received burst and the currently received burst are not combined. Way.

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