KR101346438B1 - Apparatus and method for processing packets in mobile communication system - Google Patents

Abstract

Disclosed are a packet processing apparatus and a method capable of processing a packet more quickly and efficiently by exchanging information between a hybrid-ARQ processor and an RLC processor through separate signal processing. According to an embodiment, the receiving side RLC processing unit, upon receiving the packet, generates a packet discard command signal for a packet in which an error has occurred, and the receiving side Hybrid-ARQ processing unit recovers an error of the corresponding packet through Hybrid-ARQ processing. If not, the ACK signal is transmitted to the peer Hybrid-ARQ processor (transmitting-side Hybrid-ARQ processor) according to the packet discard command signal so that the next packet can be transmitted. According to another embodiment, the receiving side Hybrid-ARQ processing unit, upon receiving a packet, generates a packet status report signal, and transmits a NAK signal to a peer Hybrid-ARQ processing unit (transmitting side Hybrid-ARQ processing unit) for a packet in which an error occurs. The RLC processing unit calculates the RLC-NAK delay time by using the packet status report signal, and delays the RLC-NAK signal by the RLC-NAK delay time for the packet in error. To the peer RLC processing section (transmitting side RLC processing section).

Hybrid-ARQ, RLC, Error Correction, Recovery, Latency

Description

Packet processing apparatus and method of mobile communication system {APPARATUS AND METHOD FOR PROCESSING PACKETS IN MOBILE COMMUNICATION SYSTEM}

The present invention relates to a mobile communication system, and more particularly, to a hybrid ARQ (hereinafter referred to as 'Hybrid-ARQ') processing unit of a physical layer or a medium access medium (MAC) layer and an RLC (Radio). Link control layer) relates to a packet transmitting and receiving apparatus and method that can process packets faster and more efficiently by exchanging information between separate processing between the processing unit of the layer.

In order to provide a multimedia service with high transmission rate and low latency in a mobile communication system, various methods of error compensation are required according to channel environment and service type. Among them, Hybrid-ARQ is an error compensation technique widely used in CDMA system, WCMDA system and next generation mobile communication system.

The Hybrid-ARQ method includes a Forward Error Correction (FEC) method including additional information capable of recovering an error in a frame to be transmitted separately, and NAK (Not Acknowledged) information to the sender for an unrecoverable error. It combines the ARQ method of transmitting the data and retransmitting the data. That is, the hybrid-ARQ method attempts error correction through the FEC at the receiving side, and if the error correction fails, determines whether to retransmit using an error detection code such as a cyclic redundancy check (CRC). In this case, instead of discarding the packet in error, it is combined with the retransmitted packet (Soft-Combining) to increase the error correction effect. A method of allowing a retransmission packet to be transmitted in the same manner as the first transmitted packet is called "Chase Combining", and a method of sending redundancy such as parity bits of an additional channel code is called "Incremental Redundancy". When transmitting redundancy, a redundancy version is included and transmitted. That is, when an error occurs and retransmits, the retransmission packet having the same bit structure as the original packet (previous packet) is called "Chase Combining", and the non-identical one is called "Incremental Redundancy".

In Hybrid-ARQ, the receiver attempts to detect and recover errors for packets individually, up to the maximum number of Hybrid-ARQ processes, and sends a NAK (or NACK) message for uncorrectable packets. A packet is sent and retransmitted, and an ACK signal is sent to packets that are recoverable or normally received so that the sender can send the next packet. Hybrid-ARQ methods include 'Stop-And-Wait (SAW) ARQ' and 'Multiple SAW ARQ' and mainly use multiple SAW ARQ. As shown in FIG. 1, in the SAW ARQ scheme, the transmitter transmits the next packet only after receiving a feedback such as ACK or NAK (or NACK) from the receiver for each packet transmitted by the transmitter. In order to improve the slow transmission speed of the SAW ARQ scheme, as shown in FIG. 2, the multiple SAW ARQ scheme transmits packet 1 at the transmitting side (receiving processing for a predetermined time at the receiving side). The sender transmits the next packet, that is, packet 2, packet 3, and packet 4, during the reception processing time.

Above the lower layer (MAC layer) in which Hybrid-ARQ processing is performed, an RLC layer which is a data link layer exists. Multiple frames that are not recovered due to Hybrid-ARQ or that are not recovered by successive errors are delivered to the RLC layer. In the RLC layer, data order and error correction are performed in association with each peer RLC between the base station and the UE. Error Correction). Error recovery in the RLC layer is performed through the RLC-NAK signal, which is a retransmission recovery method in the pure RLC layer that is not associated with Hybrid-ARQ, and thus, is also referred to as 'Outer-ARQ'. The hierarchical structure between the RLC and the Hybrid-ARQ is shown in FIG. 3.

As shown in FIG. 3, transmission and reception are performed between the Hybrid-ARQ processing unit and the peer Hybrid-ARQ processing unit by a Hybrid-ARQ operation, and the RLC processing unit and the Peer RLC processing unit are transmitted and received by an RLC operation. This is done. There is only a transmission function for bearer data without a separate interworking relationship between the Hybrid-ARQ processor and the RLC processor.

Hybrid-ARQ processing unit can quickly recover the error occurrence in the physical layer (MA) or physical layer (MAC) layer to ensure a fast transmission speed in the wireless environment. However, due to the characteristics of the Hybrid-ARQ scheme, there is a possibility that the order of packets transmitted and received separately is reversed. Specifically, when the packets are delivered to the RLC processing unit (receiving side RLC processing unit) which is higher layer without any information on the process processed by the hybrid-ARQ processing unit (receiving side Hybrid-ARQ processing unit), the packet is received by the receiving RLC processing unit. In this case, a separate RLC-NAK signal for error recovery may be unnecessarily transmitted to the peer RLC processing unit (the transmitting side RLC processing unit). In this case, even if the packet is recovered by the hybrid-ARQ processing unit (transmitting-receiving hybrid-ARQ processing unit), the peer RLC processing unit retransmits the same packet by receiving the RLC-NAK. Since a packet of information (Duplicated Octet) is dually received from the Hybrid-ARQ processor and the peer RLC processor, there is a problem in that transmission efficiency is lowered. In addition, if the Hybrid-ARQ processor continuously makes an effort to recover an error with respect to packets already determined to be discarded by the receiving RLC processing unit, the receiving RLC processing unit peers to the packet that will not be processed. Receiving a packet from the RLC processing unit discards the same packet received from the Hybrid-ARQ processing unit. Since the hybrid-ARQ processing for error recovery is performed, there is a problem in that transmission efficiency is lowered.

SUMMARY OF THE INVENTION An object of the present invention is to provide a packet processing apparatus and method capable of processing a packet more quickly and efficiently by exchanging information through separate signal processing between a Hybrid-ARQ processor and an RLC processor in a mobile communication system.

According to an aspect of the present invention, there is disclosed a packet processing apparatus and method capable of processing a packet more quickly and efficiently by exchanging information between separate Hybrid-ARQ processing units and RLC processing units through separate signal processing. According to an embodiment, the receiving side RLC processing unit, upon receiving the packet, generates a packet discard command signal for a packet in which an error has occurred, and the receiving side Hybrid-ARQ processing unit recovers the error of the corresponding packet through Hybrid-ARQ processing. If not, the ACK signal is transmitted to the peer Hybrid-ARQ processor (transmitting-side Hybrid-ARQ processor) according to the packet discard command signal so that the next packet can be transmitted. According to another embodiment, the receiving hybrid-ARQ processing unit generates a packet status report signal upon receiving a packet, and sends a NAK signal to a peer hybrid-ARQ processing unit (transmitting-side Hybrid-ARQ processing unit) for a packet having an error. The RLC processing unit calculates the RLC-NAK delay time by using the packet status report signal, and delays the RLC-NAK signal by the RLC-NAK delay time for the packet in error. To the peer RLC processing section (transmitting side RLC processing section).

According to the present invention, by performing signal processing for error recovery and correction through organic interworking between layers, it is possible to have improved packet transmission / reception characteristics, and to improve the overall transmission rate of the mobile communication system as well as the subscriber according to the reliability of data. There is an advantage to improve the perceived call quality.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions will not be described in detail if they obscure the subject matter of the present invention.

Independently of the Hybrid-ARQ processor, the RLC processor operates by the RLC protocol. When the receiving side RLC processor receives the packet from the receiving Hybrid-ARQ processing unit, it checks whether the RLC sequence packet is an In-sequence packet or an Out-of-sequence packet. The packet is stored in an in-sequence queue to send the received packets to a higher layer, and when an out-of-sequence packet is received, that is, a hole is detected, a hole management queue. Alternatively, after registering a hole in a hole register, the received out-of-sequence packets are stored in a re-sequence queue. The receiving side RLC processing unit transmits the RLC-NAK signal to the peer RLC processing unit (transmitting side RLC processing unit) and buffers the corresponding packets until retransmitted from the peer RLC processing unit. If the RLC-NAK signal is transmitted and the packet is not retransmitted from the peer RLC processor for a certain time, the RLC processor transfers the packets stored in the Re-sequence queue to the In-sequence queue and transmits them to the upper layer as they are. Aborting. Here, time management is managed through an abort timer. The discard timer is a timer for discard processing when retransmission is not performed properly, such as a loss of a NAK signal or an error in a retransmitted packet. When the discard timer expires, the RLC processor transfers the packets stored in the Re-sequence queue to the In-sequence queue and delivers them to the upper layer.

Hereinafter, the peer hybrid-ARQ processor and the peer RLC processor of the reception-side hybrid-ARQ processor and the RLC processor refer to the "transmitter-side hybrid-ARQ processor" and the "transmitter-side RLC processor".

In the above, a process of generating an out-of-sequence packet due to the hybrid-ARQ processing unit will be described with reference to FIGS. 4 and 5.

In an embodiment, as shown in FIG. 4, when the transmitting Hybrid-ARQ processing unit transmits packets of A, B, C, D, E, F, G, and H in order, the packet B is continuous for Packet B. Error occurs and the receiving Hybrid-ARQ processor generates the NAK signal continuously and retransmits normally after only 4 times, and the receiving RLC processor performs the sequence of A, C, D, E, F, G, H, and B. Receive packets. However, when receiving the packets in this order, according to the RLC protocol processing criteria, the receiving side RLC processing unit detects a hole for Packet B after receiving Packet C and immediately sends it to the peer RLC processing unit for retransmission for Packet B. Transmit RLC-NAK signal. However, although retransmission for Packet B is eventually made in the Hybrid-ARQ processor of the transmitting side, Packet B is retransmitted for the Packet R in the peer RLC processor.

FIG. 5 illustrates an example in which an out-of-sequence occurs for a packet 2 at the receiving side when the transmitting side sequentially transmits packet 0 to packet 5 to the receiving side. When Packet 0 and Packet 1 are normally transmitted by the transmitting Hybrid-ARQ processor, the receiving Hybrid-ARQ processor transmits an ACK signal to the peer Hybrid-ARQ processor. However, due to the error of packet 2, the receiving hybrid-ARQ processor transmits the NAK signal to the transmitting hybrid-ARQ processor. Therefore, the transmitting Hybrid-ARQ processor retransmits the packet 2 that has received the NAK signal, and the packet 3 is delayed due to the delay time until the retransmission (that is, the delay until the error recovery time can be received by the transmitting Hybrid-ARQ processor). And packet 4 are normally transmitted to the receiving hybrid-ARQ processor, and the receiving hybrid-ARQ processor delivers the packet 3 and the packet 4 to the receiving RLC processor. In this case, the receiving side RLC processing unit receives the packets in the order of packet 0, packet 1, packet 3, and packet 4, and recognizes that a hole has occurred for packet 2 at the moment of receiving packet 3, and immediately proceeds to RLC. Transmit the NAK signal to the peer RLC processor. However, if an error corrected packet 2 is received in response to a retransmission request due to a NAK signal from the transmitting Hybrid-ARQ processor, the receiving RLC processor re-sequences the packet 3 and the packet 4 including the packet 2 to an upper layer. Send. In addition, the peer RLC processor retransmits packet 2 to the receiver RLC processor according to a retransmission request due to the RLC-NAK signal from the receiver RLC processor, and as a result, the receiver RLC processor is a hybrid-ARQ processor (sender-receiver side). Since duplicate packet 2 has already been received from the peer RLC processor, the packet 2 (Duplicated Octet) is discarded (Discard).

The packet processing apparatus of the present invention sets a direct signaling path between a Hybrid-ARQ (physical layer or MAC layer) and a higher layer, that is, an RLC layer, in a mobile communication system using Hybrid-ARQ, and sets the corresponding signal path. Sends and receives an HR signal (packet related information). To this end, as shown in FIG. 6, each of the Hybrid-ARQ processor 61 and the RLC processor 62 includes separate blocks 611 and 622 for signal processing. That is, the Hybrid-ARQ processor 61 includes an RLC interworking processor 611 that transmits an HR signal to the RLC processor 62 or receives and processes an HR signal from the RLC processor 62. The RLC processor 62 In addition to the RLC transmission / reception processing units 621 and 623, the Hybrid-ARQ interworking processing unit 622 is provided to transmit the HR signal to the Hybrid-ARQ processing unit 61 or to receive and process the HR signal from the Hybrid-ARQ processing unit 61.

The RLC interworking processor 611 of the Hybrid-ARQ processor 61 receives and processes the H-R signal (packet related information) received from the RLC processor 62. An example of the H-R signal received from the RLC processor 62 is a packet discard command signal. In one embodiment, the packet discard command signal indicates that the RLC processing unit 62 has entered an abort procedure for a packet in which an error occurs. When the packet discard command signal is received from the receiving RLC processing unit 62, the packet discard command signal is received. The receiving Hybrid-ARQ processor 61 no longer sends a NAK signal to the peer Hybrid-ARQ processor (transmitting-side Hybrid-ARQ processor) even if the packet corresponding to a specific Hybrid-ARQ process has not been recovered from error. Send an ACK signal so that the packet can be transmitted. The packet discard command signal includes discarded Hybrid-ARQ Process Number to be Discarded information. The packet discard command signal is used to stop retransmission of a specific packet within the maximum number of retransmissions of the Hybrid-ARQ when the delay sensitive service does not require too many retransmissions in the Hybrid-ARQ of the specific packet. do. In one embodiment, the packet discard command signal may be used during handover between the system and the base station.

Referring to FIG. 7, an example of stopping a retransmission through a packet discard command signal indicates that an error occurs for a packet B, but a retransmission is performed in a hybrid-ARQ processor (transmitter-receive hybrid-ARQ processor). If a packet B needs to be discarded (for example, the packet B has already been received from the peer RLC processor or the discard timer expires), the packet discard command signal is transmitted to the receiving hybrid-ARQ processor. Thus, the receiving Hybrid-ARQ processing unit no longer makes a retransmission request (NAK signal) for the Packet B to the peer Hybrid-ARQ processing unit. When the receiving Hybrid-ARQ processor receives the packet discard command signal, even if an error occurs in the corresponding Hybrid-ARQ processing number (hole), the receiving Hybrid-ARQ processor does not transmit the ACK signal to the peer Hybrid-ARQ processor. By transmitting, the peer Hybrid-ARQ processor transmits the next packet I. In one embodiment, when the transmitting hybrid-ARQ processor transmits packets of A, B, C, D, E, F, G, and H in order, an error occurs for packet B continuously and the receiving hybrid If the ARQ processor generates the NAK signal twice and subsequently generates an ACK signal according to the packet discard command signal from the receiver RLC processor, and transmits packet I normally, the receiver RLC processor A, C, D, E Receive packets in the order of F, G, H, and I.

The Hybrid-ARQ interworking processor 622 of the RLC processor 62 receives and processes the H-R signal (packet related information) received from the Hybrid-ARQ processor 61. An example of the H-R signal received from the Hybrid-ARQ processing unit 61 is a packet status report signal. In one embodiment, the packet status report signal includes a current Hybrid-ARQ process number, a CRC result value of the current Hybrid-ARQ process, a previous Hybrid-ARQ process number, and a CRC result value of the previous Hybrid-ARQ process.

The receiving side RLC processing unit 62 receives the RLC-NAK signal from the receiving side Hybrid-ARQ processing unit 61 before transmitting the RLC-NAK signal to the peer RLC processing unit (the transmitting side RLC processing unit) in order to recover a hole generated in the RLC layer. It is determined whether to transmit the RLC-NAK signal in consideration of the packet status report signal. That is, the receiving side RLC processing unit 62 does not immediately transmit the RLC-NAK signal to the peer RLC processing unit even when a hole is generated, and the packet in which an error occurs based on the packet status report signal is transmitted-to-receiving side Hybrid. Wait until the ARQ processor can recover. Where time is the RLC-NAK delay time. The process of calculating the RLC-NAK delay time will be described in detail below. In general, the RLC protocol is a layer having no interworking relationship with the upper layer and the lower layer, but in the present invention, the RLC protocol has a close relationship with the hybrid-ARQ processing unit 61 of the lower layer.

The procedure of determining whether the RLC-NAK signal is delayed for a predetermined time by the RLC processor 62 is as follows.

1. If the CRC result of the current Hybrid-ARQ process is Fail:

If the current Hybrid-ARQ process number is equal to "NUM_MAX_HARQ_PROC-1", the receiving RLC processing unit 62 immediately transmits the RLC-NAK to the peer RLC processing unit (transmitting side RLC processing unit). Here, "NUM_MAX_HARQ_PROC-1" is the number of NAK signals sent from the receiving Hybrid-ARQ processor 61 to the peer Hybrid-ARQ processor (transmitting-side Hybrid-ARQ processor), for example, '3' in the WCDMA network, and is an LTE network. Is '8'.

2. If the CRC result of the current Hybrid-ARQ process is successful (see Fig. 8):

(1) If the received octet is not an expected sequence, that is, not in-sequence delivery, the NAK delay time according to each previous Hybrid-ARQ processing is calculated and the NAK delay time is' 0. If not, the RLC-NAK delay timer is driven, and the delay timer delays the RLC-NAK signal by the RLC-NAK delay time.

(2) If the received Octet is in Expected Sequence, that is, In-Sequence Delivery, the RLC-NAK delay timer is processed without driving.

(3) When the RLC NAK delay timer expires, the receiving side RLC processing section 62 transmits the RLC-NAK signal to the peer RLC processing section (transmitting side RLC processing section).

As shown in FIG. 9, the RLC processing unit 62 directly transmits the RLC-NAK signal to the peer RLC processing unit as shown in FIG. 9 in the case of “Current CRC result of the current Hybrid-ARQ process”. Instead of transmitting, the RLC-NAK delay timer is driven to delay the RLC-NAK signal. In one embodiment, when the transmitting side transmits the packet 0 to the packet 5 sequentially to the receiving side, when the transmitting side Hybrid-ARQ processing unit transmits the packet 0 and the packet 1 normally, the receiving hybrid-ARQ processing unit 61 respectively. Transmits an ACK signal to the peer Hybrid-ARQ processor. However, if packet 3 is received first due to an error of packet 2, the receiving hybrid-ARQ processing unit 61 transmits a NAK signal to the peer hybrid-ARQ processing unit, but the receiving RLC processing unit 62 is a packet 2 error. Even if a detected hole is detected, the RLC-NAK signal is not immediately generated. At this time, the RLC-NAK signal is generated by the RLC-NAK delay time, the RLC-NAK delay time is calculated based on the packet status report signal. Therefore, the receiving side RLC processing unit 62 holds the transmission of the RLC-NAK signal until a time (RLC-NAK delay time) at which packet 2 may be recovered after receiving an error from the transmitting-receiving hybrid-ARQ processing unit. do. In FIG. 9, the packet 2 is recovered from the transmitting-receiving Hybrid-ARQ processor within the RLC-NAK delay time by the RLC-NAK delay timer and transferred to the receiving-side RLC processing unit 62. This is because the receiving side RLC processor 62 is re-sequencing without transmitting the RLC-NAK signal to the peer RLC processor. Therefore, the duplicated Octet phenomenon does not occur in the reception side RLC processing unit 62. The RLC-NAK delay timer is canceled when Packet 2 is received by the receiving side RLC processing unit 62. If Packet 2 is not received from the transmitting-receiving Hybrid-ARQ processor during the RLC-NAK delay time by this RLC-NAK delay timer, the receiving-side RLC processing unit 62 transmits the RLC-NAK signal to the peer RLC processing unit. .

Referring to FIG. 8, the processing procedure of “Current Hybrid-ARQ Process CRC Result of Success” of FIG. 2 will be described in detail as follows.

When the receiving side RLC processing unit 62 receives the packet from the receiving side Hybrid-ARQ processing unit 61 (801), it checks whether the RLC sequence packet is an In-sequence packet or an Out-of-sequence packet (802). ). As a result of the check, if the In-sequence packet is normally received, the receiving side RLC processor 62 stores the received packet in an In-sequence queue to send the received packet to the upper layer (803). If the check result is an out-of-sequence packet, that is, if a hole is detected (Detect), after receiving the register (Hole) in the hole management queue (Hole Management Queue) or the hole register (Hole Register) (804), receive The out-of-sequence packets are stored in the Re-sequence queue (805).

The receiving side RLC processor 62 checks whether the RLC-NAK signal is enabled or disabled (806).

As a result of the check, if the RLC-NAK signal is disabled, the receiving side RLC processing unit 62 transmits the RLC-NAK signal to the peer RLC processing unit (the transmitting side RLC processing unit) (809), and aborts timer (Abort Timer). (810). The discard timer is a timer for discard procedure when the RLC-NAK signal is lost or retransmission is not properly performed, such as an error in the retransmitted packet. When the discard timer expires (811), the receiving side RLC processing unit 62 transfers the packets stored in the Re-sequence queue to the In-sequence queue (812) and delivers them to the upper layer (813).

As a result of the check, if the RLC-NAK signal is enabled, the receiving RLC processing unit 62 calculates the RLC-NAK delay time (807). If the delay time is '0', the RLC-NAK is sent to the peer RLC processing unit. The signal is transmitted (809) and the discard timer is driven (810). However, if the delay time is not '0', the receiving side RLC processor 62 drives the RLC-NAK delay timer (814) and delays the RLC-NAK signal (815) within a timer expiration time (RLC-NAK delay time). (816). When the RLC-NAK delay timer is completed (815), the receiving side RLC processing section 62 transmits the RLC-NAK signal to the peer RLC processing section (809), and drives the discard timer (810).

The process of calculating the RLC-NAK delay time will now be described with reference to FIGS. 10 and 11.

The time point for calculating the RLC-NAK delay time is a case where the CRC result value of the current Hybrid-ARQ process is successful, and a case where a hole is detected in the receiving RLC processing unit 62.

Assuming that the transmitting Hybrid-ARQ processor transmits the packets of A, B, C, D, E, F, G, H in order, the receiving RLC processor 62 receives A, C, D, E, Receive packets in the order of F, G and H. However, the receiving side RLC processing unit 62 registers the packet B as a hole because the expected packet B was not received when the packet C was received. At this time, the receiving side RLC processing unit 62 should retransmit packet B. First, the receiving hybrid-ARQ processing unit 61 detects an error of the packet B and sends it to the peer hybrid-ARQ processing unit (the transmitting side Hybrid-ARQ processing unit). Since the NAK signal is transmitted, the receiving side RLC processing unit 62 does not transmit the RLC-NAK signal to the peer RLC processing unit until the retransmission processing for Packet B is performed by the transmitting side-receiving Hybrid-ARQ processing unit. At this time, it is the RLC-NAK delay timer that determines the transmission time of the RLC-NAK signal. The reception side RLC processor 62 suspends transmission of the RLC-NAK signal by the RLC-NAK delay time by the RLC-NAK delay timer.

To calculate the RLC-NAK latency, it is important how many times the Hybrid-ARQ is retransmitting. In one embodiment, if Packet B fails in the first transmission as shown in Fig. 10 (packet C is normally received and packet C is detected at the time packet C is received), the RLC-NAK delay time is " Time taken to retransmit in Hybrid-ARQ × maximum number of retransmissions. Here, assuming that the time taken for retransmission in Hybrid-ARQ is '3', since the maximum number of retransmissions is '3', the RLC-NAK delay time becomes "9". In another embodiment, as shown in FIG. 11, when packet B fails in the first and second transmissions (packet C and D fail in the first transmission and succeed in the second transmission (retransmission), the retransmitted packet C is Detecting an error of Packet B at the time of reception), the RLC-NAK delay time is "the time taken to retransmit in Hybrid-ARQ x the number of remaining retransmissions." In this case, assuming that the time required for retransmission in Hybrid-ARQ is '3', since the number of retransmissions remaining is '2', the RLC-NAK delay time is “6”.

Including the above embodiment, the generalized calculation method of the RLC-NAK delay time is shown in Equation 1 below.

RLC-NAK Delay Time [1] = 12 × (3-Other [1] Subpacket ID) + (4 * Interlace interval) / * 12 and 4 are for adjusting the units in slots * /

RLC-NAK Delay Time [2] = 12 × (3-Other [2] Subpacket ID) + (4 * Interlace interval) / * 12 and 4 are for adjusting the units in slots * /

RLC-NAK delay time = MAX (RLC-NAK delay time [1], RLC-NAK delay time [2]) / set to the higher of the two /

In Equation 1, an interlace interval representing a difference value of each interlace is calculated through Equation 2 below.

If this Subpacket ID <= Other [x] Subpacket ID and CRC value of Other [x] interlace is fail,

interlace interval [1] = (other [1] interlace number + 3-this interlace number) mod 3

interlace interval [2] = (other [2] interlace number + 3-this interlace number) mod 3

In the above equation, "This interlace" is Hybrid-ARQ information of the currently received subpacket, "Other interlace 1" is Hybrid-ARQ information of the subpacket received just before This, and "Other interlace 2" is preceded by Other 1. Hybrid-ARQ information of the received subpacket, "interlace number" is 0-2 (in case of 3 Hybrid-ARQ processing, interlace number is 0-2), and "Sub packet ID" is the number of retransmissions It is from 0 to 3 by indication.

While the invention has been described in connection with some embodiments herein, it should be understood that various modifications and changes can be made without departing from the spirit and scope of the invention as would be understood by those skilled in the art. something to do. It is also contemplated that such variations and modifications are within the scope of the claims appended hereto.

1 is an explanatory diagram showing a Stop-And-Wait ARQ scheme of Hybrid-ARQ.

2 is an explanatory diagram showing a Multiple Stop-And-Wait ARQ scheme of Hybrid-ARQ.

3 illustrates a hierarchical configuration between Hybrid-ARQ and RLC.

4 is a diagram illustrating an example of an out-of-sequenced packet generation process due to Hybrid-ARQ processing.

5 is a diagram illustrating another example of an out-of-sequenced packet generation process due to Hybrid-ARQ processing.

6 illustrates a packet processing apparatus between Hybrid-ARQ and RLC according to an embodiment of the present invention.

7 is an explanatory diagram showing a packet processing process according to an embodiment of the present invention.

8 is a flowchart illustrating a packet receiving process according to an embodiment of the present invention.

9 is an explanatory diagram showing a packet processing procedure according to another embodiment of the present invention.

10 is an explanatory diagram showing a process of calculating a NAK delay time according to an embodiment of the present invention.

11 is an explanatory diagram showing a process of calculating a NAK delay time according to another embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

61: Hybrid-ARQ processor 62: RLC processor

611: RLC interworking unit 621: RLC receiving processing unit

622: H-ARQ interworking processing unit 623: RLC transmission processing unit

Claims (14)

A packet processing apparatus of a mobile communication system, A receiving side RLC processing unit operable to generate a packet discard command signal with respect to a packet in which an error occurs when the packet is received; And Receiving hybrid operative to transmit an ACK signal to the transmitting-side Hybrid-ARQ processing unit according to the packet discard command signal so that the next packet can be transmitted even if the error of the corresponding packet is not recovered by Hybrid-ARQ processing. Packet processing apparatus comprising an ARQ processing unit. The method of claim 1, The packet discard command signal includes removed Hybrid-ARQ process number information. 3. The method of claim 2, And the receiving side RLC processing unit generates an RLC-NAK signal for the error generating packet, transmits the RLC-NAK signal to the transmitting side RLC processing unit, and retransmits the error generating packet from the transmitting side RLC processing unit. A packet processing apparatus of a mobile communication system, A receiving side Hybrid-ARQ processing unit generating a packet status report signal upon receiving the packet, and transmitting a NAK signal to the transmitting side Hybrid-ARQ processing unit for recovering the error of the corresponding packet; And The RLC-NAK delay time, which is likely to be recovered after receiving an error at the transmitting and receiving hybrid-ARQ processing units, is calculated using the packet status report signal, and the RLC-NAK signal is calculated for the error-producing packet. -A packet processing apparatus comprising a receiving side RLC processing unit operable to delay by a NAK delay time to transmit to the transmitting side RLC processing unit. 5. The method of claim 4, The packet status report signal includes a current Hybrid-ARQ process number, a CRC result value of a current Hybrid-ARQ process, a previous Hybrid-ARQ process number, and a CRC result value information of a previous Hybrid-ARQ process. The method of claim 5, The RLC-NAK delay time is calculated by multiplying the time taken to be retransmitted in the Hybrid-ARQ, the maximum number of retransmissions or the maximum number of remaining retransmissions. 7. The method according to any one of claims 1 to 6, The receiving side Hybrid-ARQ processing unit includes an RLC interworking processing unit for interworking with the receiving side RLC processing unit, and the receiving side RLC processing unit includes a Hybrid-ARQ interworking processing unit for interworking with the receiving side Hybrid-ARQ processing unit. Packet processing apparatus to do. As a packet processing method of a mobile communication system, Receiving, by the receiving hybrid-ARQ processor, a packet from the transmitting hybrid-ARQ processor; Generating, by the receiving side RLC processor, a packet discard command signal with respect to an error occurrence packet; And In order that the next packet can be transmitted even if the error of the corresponding packet is not recovered by the hybrid-ARQ process, the receiving hybrid-ARQ processor sends an ACK signal to the error-occurring packet according to the packet discard command signal. Packet processing method comprising the step of transmitting to the processing unit. 9. The method of claim 8, The packet discard command signal includes removed Hybrid-ARQ process number information. As a packet processing method of a mobile communication system, Receiving, by the receiving hybrid-ARQ processor, a packet from the transmitting hybrid-ARQ processor; The receiving side RLC processor calculates an RLC-NAK delay time that is likely to be recovered after receiving an error in the transmitting side and the receiving side Hybrid-ARQ processing unit using the packet status report signal transmitted from the receiving side Hybrid-ARQ processing unit. Delaying an RLC-NAK signal by the RLC-NAK delay time with respect to an error occurrence packet; And And transmitting, by the receiving Hybrid-ARQ processor, a NAK signal to the transmitting Hybrid-ARQ processor for the packet in which an error occurs and recovering an error of the corresponding packet. The method of claim 10, And when the RLC-NAK delay time expires, transmitting, by the receiving RLC processing unit, an RLC-NAK signal to a transmitting RLC processing unit. 12. The method of claim 11, The packet status report signal includes a current Hybrid-ARQ process number, a CRC result value of a current Hybrid-ARQ process, a previous Hybrid-ARQ process number, and a CRC result value information of a previous Hybrid-ARQ process. The method of claim 12, The RLC-NAK delay time is calculated by multiplying the time taken to be retransmitted in the Hybrid-ARQ, the maximum number of retransmissions or the maximum number of remaining retransmissions. 14. The method according to any one of claims 8 to 13, The Hybrid-ARQ is processed in a MAC layer.

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