KR20060039556A - Method and system for transmitting packet data by using plural number channel automatic repeat request for use in portable internet network - Google Patents

Abstract

The present invention relates to a method and system for transmitting packet data using a multi-channel automatic retransmission request in a portable Internet network.

The present invention provides a method of manufacturing a packet including: (a) packing packet data into a plurality of packets when packet data to be transmitted to the PSS is generated, and selecting any one of the plurality of packets as a transmission scheduled packet; (b) The traffic channel allocated to the PSS is divided into a plurality of logical channels to transmit a packet to be transmitted to the PSS through one of the plurality of logical channels, and a timer for the logical channel is set. Operating; (c) checking whether the PSS has received the packet and generating an acknowledgment signal according to the result of the packet transmission to the RAS through the logical channel in which the packet was received; (d) confirming whether or not the RAS has received an acknowledgment signal and determining a transmission schedule packet and determining whether all of the plurality of packets have been transmitted; And (e) if the plurality of packets have not been transmitted as a result of the determination of step (d), proceeding to step (b) of the packet data transmission method using the multi-channel ARQ in the portable Internet network. to provide.

According to the present invention, it is possible to improve error control performance and improve system implementation by reducing excessive retransmissions and performing only retransmission of the same packet in a wireless environment where errors frequently occur.

Mobile Internet, Auto Retransmission Request, Logical Channel, WiBro, ARQ, Logical Channel

Description

Method and system for transmitting packet data using multi-channel ARX in portable internet network {Method and System for Transmitting Packet Data by Using Plural Number Channel Automatic Repeat Request for Use in Portable Internet Network}

1 is a view for explaining a conventional ARQ scheme,

2 is a block diagram schematically illustrating a packet data transmission system using 2 channel ARQ in a mobile Internet network according to a preferred embodiment of the present invention;

3A and 3B are flowcharts illustrating a packet data transmission method using 2 channel ARQ in a mobile Internet network according to a preferred embodiment of the present invention;

4 is a view for explaining a two-channel ARQ according to a preferred embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

110: transmitter 120: receiver

210: PSS 220: mobile Internet

222: RAS 224: ACR

226: HA 228: AAA

230: IP network 402: packet # 1

404: Packet # 2 406: ACK # 1                 

408, 416: Packet # 3 410: ACK # 2

412: packet # 4 414: NACK # 3

418: ACK # 4 420: Packet # 6

422: ACK # 3 424: packet # 5

The present invention is a packet data transmission using a multi-channel automatic retransmission request (ARQ: Automatic Repeat Request, hereinafter referred to as 'ARQ') in a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network) It relates to a method and a system. More specifically, in the portable Internet network, packet data is continuously transmitted by using a Stop and Wait ARQ method in which a wireless channel for data transmission is logically divided into a plurality of channels. DL MAP (Logical Channel Identification) information is added to a DL MAP message and transmitted together with the packet data transmission, and the terminal of the mobile Internet subscriber receiving the packet data (hereinafter referred to as a subscriber terminal). The present invention relates to a method and a system for transmitting packet data by determining whether to retransmit according to a received confirmation signal by adding logical channel ID information to an uplink map (UL MAP) message.

Recently, a wireless Internet service that provides an Internet communication service to a user of a mobile communication terminal through a wireless communication network has emerged. In order to provide such a service, a mobile communication system has been developed through a first generation analog AMPS (Advanced Mobile Phone System) system and a second generation cellular / personal communication service (PCS) system. The IMT-2000 (International Mobile Telecommunication 2000), which is a third generation mobile communication system established by ITU-R as a standard, is commercially available.

The IMT-2000 is, for example, CDMA 2000 1x, CDMA 2000 EV-DO, WCDMA, etc., which can service data communication at a higher speed than the data rates supported by existing IS-95A, IS-95B, and IS-95C networks. System. In particular, using the IMT-2000 system, it is possible to provide various multimedia services at a higher speed as well as to improve the quality of services using existing voice communication services and WAP (Wireless Application Protocol).

However, the existing mobile communication system has a limitation in providing high-speed wireless Internet due to high base station construction cost and high usage rate of the wireless Internet, and a limited screen size of the mobile communication terminal. Wireless Local Area Network (WLAN) technology has limitations in providing air services due to problems such as radio wave interference and a narrow coverage area. Accordingly, a portable Internet system that can use a high-speed wireless Internet service at a low rate while moving has emerged.

The portable Internet system can use various information and contents by accessing the Internet in indoor and outdoor stationary environments and mobile environments of walking speed and low to medium speed using various types of portable terminals such as laptops, PDAs and handheld PCs. It is a service. In addition, it provides mobility of 60 km / h per hour, provides downlink transmission speed of 24 Mbps, and can provide downlink transmission speed of 50 Mbps by applying Multiple Input Multiple Output (MIMO) system. Wireless data system.

In addition, the portable Internet system uses a frequency band of 2.3 GHz, and draws a time division duplex (TDD) by a duplex method and a multiple access method to effectively use an allocated frequency spectrum. Orthogonal Frequency Division Multiple Access (OFDMA) is used for this purpose. In addition, since the portable Internet system has a wide frequency bandwidth and uses the OFDMA / TDD scheme, the portable Internet system provides high quality wireless data service in an environment of medium to low speed mobility. Accordingly, the portable Internet system can provide a video telephone service requiring a high quality wireless data communication with an improved quality than a video telephone service using a mobile communication system.

Meanwhile, the above-described wireless systems use the ARQ method as a method for controlling an error in order to increase the reliability of data frame transmission, and typically, the stand-by ARQ method is used as the ARQ method.

1 is a view for explaining a conventional ARQ method.

1A shows a typical stop wait ARQ scheme. In the stop waiting ARQ scheme, the transmitter 110 transmits a predetermined packet among the packet data to be transmitted to the receiver 120 and then receives a signal indicating that the packet has been normally received from the receiver 120 (hereinafter, referred to as a reception success signal). In this case, the next predetermined packet is transmitted to the transmitter 110. That is, when the transmitter 110 transmits the packet # 1 at 1A and operates the timer and receives the ACK (Acknowledge) # 1 signal from the receiver 120, the transmitter 110 transmits the next packet, Packet # 2, and operates the timer. At this time, the receiver 120 did not receive the packet # 2 due to some reason, but did not transmit the ACK # 2 signal, or the receiver 120 transmits the ACK # 2 signal, but the transmitter 110 receives the ACK # 2 signal. If the timer fails to operate, the timer expires, and when the timer expires, the packet # 2 is transmitted to the receiver 120 again. In this way, data errors that may occur during transmission and reception are overcome.

When using the confessional ARQ method or the selective retransmission ARQ method, it shows high efficiency in the environment where there is little transmission error such as the wired environment, but in the case where the error occurs frequently such as the wireless environment, the link efficiency decreases due to frequent retransmission. . Unlike a wired channel, a wireless channel frequently changes its channel state, and thus, the channel state suddenly becomes weak or deep fading, which is often caused by a bad channel state for a long time. Accordingly, the wireless systems mainly use the above-mentioned idle standby ARQ scheme instead of the Go Back N ARQ scheme or the Selective Repeat ARQ scheme used in the wired system.

1B shows the confession yen ARQ method. The confession yen ARQ method is a method in which the transmitter 110 continuously transmits a constant packet instead of transmitting a next constant packet after receiving a reception success signal from the receiver 120 after transmitting a predetermined packet among packet data. After receiving a signal indicating that the reception success signal for the transmitted packet is not received or the packet is not normally received, the corresponding packet and all packets transmitted thereafter are transmitted to the receiver 120 again. That is, in 1B, since the transmitter 110 continuously transmits the packets #a to #c to the receiver 120 and receives the ACK #a signal from the receiver 120, the transmitter 110 continuously transmits the packet #d and the packet #e. When the NACK #b is received, the packet #b to the packet #e are transmitted to the receiver 120 instead of the packet #f. This approach is less efficient when there are many or many errors in the channel.

On the other hand, the stop waiting ARQ method reduces the load on the transmission network because the amount of data in the retransmitted packet is small, but does not transmit the next packet until the ACK signal is received after the packet is transmitted. Over time, expensive wireless channels are not utilized and wasteful, reducing their efficiency.

In order to solve this problem, the CDMA system uses a 4-channel hybrid ARQ (HARQ) scheme to maximize packet transmission efficiency. In particular, the CDMA 1x EV-DV system uses the Asynchronous and Adaptive Incremental Redundancy (AAIR) scheme, which is an advanced HARQ scheme. 3A shows an example of an AAIR scheme used in a CDMA 1x EV-DV system. As shown in 3A, the transmitter 110 transmits a packet through four channels, and performs Type-2 HARQ for each channel separately from other channels, and in case of reception failure, the transmitter 110 transmits a packet. Rather than transmitting the same packet again, a packet having a HARQ structure different from a packet having a HARQ structure of the transmitted packet is transmitted. That is, the AAIR method divides into four channels such as A, B, C, and D, and continuously transmits packets A11, B11, C11, and D11 through four channels, and receives a reception failure signal NACK (for packet A11 transmission). When A) is received, a packet A12 having a HARQ structure different from that of the packet A11 is transmitted. However, the AAIR method used in the CDMA system has a disadvantage in that its configuration and operation are very complicated because it performs asynchronous retransmission through a combining technique such as HARQ, and separates each channel with a separate code.

In order to solve this problem, the present invention, while continuously transmitting the packet data by using the ARQ method that logically divided the radio channel for data transmission in a plurality of channels in the portable Internet network, the logic in the downlink map message When the subscriber station receiving the packet data transmits an acknowledgment signal by adding a logical channel ID to the uplink map message, it determines whether to retransmit according to the received acknowledgment signal. It is an object to provide a method and system for transmitting packet data.

In order to achieve this object, according to the first object of the present invention, a personal subscriber station (PSS: hereinafter referred to as "PSS") and a radio access station (RAS: RAS) is referred to as "RAS" A method for transmitting packet data between a PSS and a RAS in a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network), comprising: (a) a packet when packet data to be transmitted to the PSS occurs; Packing data into a plurality of packets and selecting any one of the plurality of packets to determine a transmission schedule packet; (b) The traffic channel allocated to the PSS is divided into a plurality of logical channels to transmit a packet to be transmitted to the PSS through one of the plurality of logical channels, and a timer for the logical channel is set. Operating; (c) checking whether the PSS has received the packet and generating an acknowledgment signal according to the result of the packet transmission to the RAS through the logical channel in which the packet was received; (d) confirming whether or not the RAS has received an acknowledgment signal and determining a transmission schedule packet and determining whether all of the plurality of packets have been transmitted; And (e) if the plurality of packets have not been transmitted as a result of the determination of step (d), proceeding to step (b) of the packet data transmission method using the multi-channel ARQ in the portable Internet network. to provide.

In addition, according to a second object of the present invention, packet data is transmitted through a wireless channel in a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network). In the system of the present invention, a packet data is packed into a plurality of packets, a traffic channel is logically divided into a plurality of logical channels, and a plurality of packets are divided into a plurality of logical channels. Send the packet to the PSS, determine whether to receive the confirmation signal from the PSS, determine the packet to be sent based on the result of the verification, determine whether all the packets have been transmitted, and then send the packet to be sent to the PSS according to the determined result. A mobile person, characterized in that it comprises a radio access station (RAS: Radio Access Station, RAS)) Provides a packet data transmission system using a multi-channel ARQ in the Internet.

In addition, according to a third object of the present invention, a radio access station (RAS) via a wireless channel using a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network) A terminal for receiving packet data including a plurality of packets from a terminal, the method comprising: (a) checking whether a packet has been received; (b) When the packet is received as a result of checking in step (a), an uplink logical channel ID (UL MAP) is set in an uplink map (UL MAP) message and an ACK is attached to the uplink map message. Generating an Acknowledge signal as an acknowledgment signal and transmitting it to the RAS; (c) confirming whether or not a DL MAP message is received if no packet is received as a result of checking in step (b); (d) When the downlink map message is received as a result of the checking in step (c), generates an uplink logical channel ID in the uplink map message and generates a NACK (Non Acknowledge) signal with the uplink map message as an acknowledgment signal. Transmitting to the RAS; And (e) if the downlink map message is not received as a result of checking in step (c), performing a series of processes including the step of proceeding to step (a). Provides a Personal Subscriber Station (PSS) for receiving packet data using

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, hereinafter referred to as a personal subscriber terminal (PSS) from a radio access station (RAS: RAS) of a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network) A packet is transmitted to a station (hereinafter referred to as a 'PSS'), but a traffic channel is logically divided into a first channel and a second channel by a RAS, and the packet data is divided into a first packet by a RAS. Packed only with 'packet # 1') to the sixth packet (hereinafter referred to as 'packet # 6'), packets # 1, packet # 3, and packet # 5 are transmitted through the first channel, The present invention will be described assuming that packet # 2, packet # 4, and packet # 6 are transmitted on a second channel.

However, the above-described assumption is for convenience of description, and in reality, packet data may be transmitted from the PSS to the RAS, the packet data may be packed into a plurality of packets, and the traffic channel is only the first channel and the second channel. The present invention is not limited to this assumption because the packet transmitted to the first channel and the second channel may be different from the above-described assumption. Therefore, the present invention also applies to a case of transmitting packet data using a wireless channel of a portable Internet network or to transmitting packet data packed into a plurality of packets.

FIG. 2 is a diagram schematically illustrating a packet data transmission system using a two-channel automatic repeat request (ARQ) in the portable Internet network. Drawing.

According to an embodiment of the present invention, a packet data transmission system using two-channel ARQ in a portable Internet network is referred to as PSS 210, RAS 222, and an access control router (ACR). 224, a home agent (HA) 226, an authentication server (AAA: Authentication, Authorization, Accounting, hereinafter referred to as 'AAA') 228, and an IP network (Internet Protocol Network) 230.

PSS (210) refers to a portable terminal that provides a high-speed wireless Internet service using the portable Internet network 220, and according to the low power RF (RF) / IF (Intermediate Frequency) module and controller function, service characteristics and propagation environment It has MAC (Media Access Control) frame variable control function, hand over function, authentication and encryption function. To this end, the PSS 210 has a built-in browser for accessing the Internet for high-speed wireless Internet. In addition, the PSS 210 may include a personal digital assistant (PDA), a hand-held PC, a notebook PC, a smart phone, and a multi-mode multiband (MM-MB). Band) terminal or the like. Here, a smart phone is a terminal that combines the advantages of a mobile communication terminal and a personal portable terminal, and refers to a terminal incorporating data communication functions such as schedule management, fax transmission and reception, which are functions of a personal portable terminal, in a mobile communication terminal. In addition, a multimode multiband terminal is a multi-modem chip that can operate in both portable Internet systems and other mobile communication systems (for example, code division multiple access (CDMA) 2000 system, wideband CDMA (WCDMA) system, etc.) Speak terminal.

The PSS 210 according to the preferred embodiment of the present invention transmits and receives a packet with the RAS 222 using 2 channel ARQ. That is, the PSS 210 according to the preferred embodiment of the present invention receives a packet from the RAS 222 through a first channel or a second channel, which is a logical channel, and includes a logical channel ID included in a downlink map message attached to the packet. By confirming that the logical channel ID is set in the uplink map message, an ACK (Acknowledge) signal including the packet identification number is generated as an acknowledgment signal and transmitted to the RAS 222. In addition, the PSS 210 according to the preferred embodiment of the present invention receives only the downlink map message from the RAS 222, and if the packet is not received by setting a logical channel ID in the uplink map message NACK including a packet identification number A Non Acknowledge signal is generated as an acknowledgment signal and transmitted to the RAS 222.

The RAS 222 is a base station of the portable Internet network 220. The RAS 222 wirelessly transmits data received from the ACR 224 to the PSS 210. The RAS 222 is a low-power radio frequency (IF) / intermediate frequency (IF) module and controller. Function, Orthogonal Frequency Division Multiple Access (OFDMA) / Time Division Duplex (TDD) packet scheduling and channel multiplexing function, service characteristics And a MAC frame variable control function, a 50 Mbps high-speed traffic real-time control function, and a hand over function according to a propagation environment. In addition, the PSS 210 and the RAS 222 have a 50 Mbps packet transmission modulation and demodulation function, a high speed packet channel coding function, a real time modem control function, and the like for data transmission.

 The RAS 222 according to the preferred embodiment of the present invention transmits and receives a packet with the PSS 210 using 2-channel ARQ. That is, the RAS 222 according to the preferred embodiment of the present invention separates and packs packet data to be transmitted to the PSS 210 into a plurality of packets, and logically divides a traffic channel into a first channel or a second channel, A plurality of packets are continuously sent to the PSS 210 via logically separated first or second channels and the timer is activated. In addition, the RAS 222 according to the preferred embodiment of the present invention transmits the next packet or the previous packet through the same logical channel depending on whether the acknowledgment signal is received from the PSS 210.

The ACR 224 is a base station controller of the portable Internet network 220. Although not shown in FIG. 1 for convenience of description, the ACR 224 accommodates a plurality of RASs 222, or between the RASs 222 or the IP network 230 with the RAS 222. As a packet access router for connecting a network, a handover control function between RASs 222, a handover function between ACRs 224, and a handover function between a base station of another network (for example, a CDMA 2000 network, a WCDMA network, etc.) and the RAS 222 And a packet routing function, an Internet connection function, and the like, and are connected to the IP network 226.

When the mobile Internet network 220 uses Mobile IP, the HA 226 performs a function of routing a packet transmitted from the outside through the Internet (not shown), and the AAA 228 is an ACR. In connection with 224, charging for the packet data used in the PSS 210 is performed, and the connection from the PSS 210 is authenticated.

The IP network 230 is a backbone network for transmitting and receiving data in the portable Internet network 220 and includes a plurality of network equipment such as a router.

3A and 3B are flowcharts for describing a packet data transmission method using 2 channel ARQ in a mobile Internet network according to a preferred embodiment of the present invention.

The portable internet network 220 provides a portable internet service to the PSS 210. Accordingly, the portable Internet network 220 connects the PSS 210 with another PSS (not shown) or an external Internet (not shown) at the request of the PSS 210 to transmit and receive packet data. to provide. At this time, there is a case where there is a request for data transmission from the other PSS (not shown) or the external Internet (not shown) to the PSS 210, so that packet data must be transmitted to the PSS 210. When packet data to be transmitted to the PSS 210 is generated, the portable Internet network 220 transmits the packet data to the RAS 222, and the RAS 222 stores the received packet data. The RAS 222 storing the packet data packs it into a plurality of packets having a maximum data size (eg, 50 bytes) that can transmit the packet data to transmit the packet data to the PSS 210. That is, the RAS 222 packs the packet data into packet # 1, packet # 2, packet # 3, packet # 4, packet # 5, and packet # 6. The RAS 222 packing the packet data into a plurality of packets determines the packet to be transmitted to the PSS 210 as a transmission scheduled packet (S302). The RAS 222 determining the transmission scheduled packet inserts a logical channel ID (DL MAP) into a downlink map (DL MAP) message to divide the logical channel into a first channel or a second channel (S304). . In this example, it is assumed that a logical channel is divided into a first channel for transmitting packet # 1. Here, the downlink map message is a message defining access to the downlink information, the number of downlink map information elements (Number of DL MAP Information Elements), the connection identifier (CID), the number of forward error correction blocks (Number) parameters of Forward Error Correction (FEC) Blocks). In the present invention, in order to implement a two-channel ARQ according to a preferred embodiment of the present invention, logical channels are distinguished by inserting a logical channel ID into a downlink map message.

According to a preferred embodiment of the present invention, two-channel ARQ divides a traffic channel for packet data transmission into two channels, which are logically a first channel and a second channel, and continuously packet data through two logical channels. Transmit, but receive the acknowledgment signal and automatically retransmit using the difference in packet data transmission time between each channel (for example, the time between transmitting packet # 1 on the first channel and then transmitting packet # 2 on the second channel). This is a method for error control to determine whether or not. Accordingly, in the present invention, the RAS 222 assigns a logical channel ID for identifying a logical channel to a downlink map message in a MAC (Media Access Control) message attached when transmitting packet data to the PSS 210 via a wireless channel. By inserting and assigning different logical channel IDs to the packet data to be continuously transmitted, attaching the downlink map message minimizes the waiting time until receiving the confirmation signal. In the present invention, the acknowledgment signal refers to an ACK (Acknowledge) signal or a NACK (None Acknowledge) signal transmitted by the PSS 210 to the RAS 222 when the packet is not received or the packet is not received.

Table 1 shows the format of a downlink map message.

In the present invention, as shown in Table 1, logical channels can be easily distinguished by inserting a logical channel ID field into a downlink map message used in the portable Internet network 220.

In step S304, the RAS 222, which divides the logical channel ID into the first channel, attaches a downlink map message to the packet # 1 to be transmitted to the PSS 210, and operates the timer provided (S306). Here, the timer is for retransmitting the transmitted packet when the acknowledgment signal is not received from the PSS 210. When the packet is transmitted, the timer is operated by the RAS 222 to determine a predetermined time, that is, the packet is sent to the PSS 210. The operation stops when sufficient time has elapsed to be transmitted and an acknowledgment signal is received. When the timer expires, the RAS 222 retransmits the previously transmitted packet. However, the timer operates separately every time a packet is transmitted through each channel to distinguish between a packet transmitted through the first channel and a packet transmitted through the second channel. In step S306, the RAS 222, which has transmitted packet # 1 through the first channel, does not stop transmission until it receives an acknowledgment signal from the PSS 210. Instead, the RAS 222 transmits the packet # 1 in a manner similar to the above-described methods S304 and S306. After dividing the logical channel into the second channel, the next packet, Packet # 2, is continuously transmitted through the second channel.

The PSS 210 checks whether a packet is received in a Dormant state or a Traffic state (S308). The PSS 210 checks the logical channel ID (hereinafter referred to as a 'downlink logical channel ID') included in the downlink message attached to the received packet when the packet is received in step S308. A logical channel ID having the same value (hereinafter, referred to as an 'uplink logical channel ID') is added to the UL map (UL MAP: Up Link Map) message to distinguish it (S310). The PSS 210, which identifies the uplink logical channel ID, generates an ACK signal for notifying that the packet has been normally received and attaches the uplink map message to generate the acknowledgment signal (S312). In the present invention, when the PSS 210 transmits an ACK signal or a NACK signal to the RAS 222 through a wireless channel, a logical channel ID for identifying a logical channel in an uplink map message of a MAC (Media Access Control) message attached to the PSS 210 is attached. Is inserted, and the same uplink logical channel ID as the downlink logical channel ID received from the RAS 222 is set.

Table 2 shows the format of an uplink map message.                     

In the present invention, as shown in Table 2, logical channels can be easily distinguished by inserting a logical channel ID field into an uplink map message used in the portable Internet network 220.

In addition, when the PSS 210 does not receive the packet as a result of checking in step S308, the PSS 210 checks whether a downlink map message has been received (S314). When the PSS 210 receives the downlink map message as a result of the check in step S314, the PSS 210 identifies the downlink logical channel ID and adds the uplink logical channel ID to the uplink map message (S316). If the PSS 210 does not receive the downlink map message as a result of checking in step S314, the PSS 210 proceeds to step S308 to check whether the packet has been received. In step S316, the PSS 210, which identifies the downlink logical channel ID and adds an uplink logical channel ID equal to the downlink logical channel ID to the uplink map message, generates a NACK signal for notifying that the packet was not received normally. The aforementioned uplink map message is attached and generated as an acknowledgment signal (S318). The PSS 210 which generated the confirmation signal in step S312 or S318 transmits the generated confirmation signal to the RAS 222 (S320).

The RAS 222 checks whether a confirmation signal has been received from the PSS 210 (S322). When the RAS 222 receives the confirmation signal as a result of checking in step S322, the RAS 222 checks the uplink logical channel ID included in the uplink map message attached to the received confirmation signal, and confirms whether the confirmation signal is an ACK signal. S324). RAS 222 checks the packet identification number included in the ACK signal when the confirmation result confirmation signal is an ACK signal in step S324, and the channel (first channel or second channel) corresponding to the logical channel ID identified in step S324 The packet having the packet identification number next to the packet identification number (packet # 3 in the case of the first channel and packet # 4 in the case of the second channel) among the packets to be transmitted is determined as the transmission scheduled packet. In addition, the RAS 222 distinguishes the logical channel ID and transmits the packet to the PSS 210 by attaching a downlink map message to the packet as shown in steps S304 and S306 in order to transmit a scheduled transmission packet (S326). . However, the downlink logical channel ID is set to the same value as the uplink logical channel ID identified in step S324.

In addition, the RAS 222 confirms in step S324 that, when the confirmation signal is not an ACK signal but a NACK signal, confirms the packet identification number included in the NACK signal, and NACK of the channel corresponding to the logical channel ID checked in step S324. The same packet having the packet identification number included in the signal (packet # 1 for the first channel and packet # 2 for the second channel) is determined to be a transmission scheduled packet and transmitted again to the PSS 210 (S328). .

In addition, the RAS 222 checks whether the timer operated in the step S306 has expired (S330) when the confirmation signal in step S322 does not receive the confirmation signal. If the timer expires, the RAS 222 confirms whether the timer has expired and proceeds to step S328 to transmit the same packet again, and if the timer has not expired, proceeds to step S322 and receives a confirmation signal. .

The RAS 222 which transmitted the transmission scheduled packet in step S326 or step S328 determines whether all the plurality of packets packed in step S302 have been transmitted (S332). If the RAS 222 does not transmit all the packets as a result of the determination in step S332, the RAS 222 proceeds to step S304 to transmit a transmission scheduled packet. In addition, the RAS 2220 terminates all procedures when all of the plurality of packets are transmitted as a result of the determination of step S332.

Through such a procedure, when the RAS 222 transmits all packets of packet data to be transmitted to the PSS 210, all processes are terminated.

4 is a view for explaining a two-channel ARQ according to a preferred embodiment of the present invention.

According to the foregoing assumption, the RAS 222 sends packet data to be transmitted to the PSS 210 by using packet # 1 402, packet # 2 404, packet # 3 408, 416, and packet # 4 412. The packet is packed into packet # 5 424 and packet # 6 420, and the traffic channel is logically divided into a first channel and a second channel. In addition, packet # 1 402, packet # 3 408, 416, and packet # 5 424 are transmitted through the first channel, and packet # 2 404 and packet # 4 (through the second channel). 412, packet # 6 420 is transmitted. The RAS 222 sets the downlink logical channel ID of the downlink map message to the first channel and transmits the packet # 1 402 attached to the downlink map message to the PSS 210 to transmit the packet # 1 402. Start the timer for the first channel while transmitting. Subsequently, the RAS 222 sets the downlink logical channel ID of the downlink map message as the second channel and transmits the packet # 2 404 attached with the downlink map message to transmit the packet # 2 404. Transmit to 210 to activate the timer for the second channel.

When the PSS 210 receives the packet # 1, the PSS 210 sets the uplink logical channel ID of the uplink map message to the first channel, generates the packet identification number # 1 information, and then attaches the uplink map message to the ACK # 1 signal ( 406 is sent to the RAS 222. In addition, when receiving the packet # 2, the PSS 210 sets the uplink logical channel ID of the uplink map message to the second channel, generates the packet identification number # 2 information, and then attaches the uplink map message to the ACK # 2. Send signal 410 to RAS 222.                     

Upon receiving the ACK # 1 signal 406 from the PSS 210, the RAS 222 checks the # 1 information, which is an uplink logical channel ID and packet identification number included in the ACK # 1 signal 406, and is next to the first channel. In order to transmit the packet # 3 408, which is a packet, the first channel is set to the logical channel ID of the downlink map message and the packet # 3 408 attached to the downlink map message is transmitted to the PSS 210. Activate the timer for the channel. In addition, upon receiving the ACK # 2 signal 410 from the PSS 210, the RAS 222 checks # 2 information, which is an uplink logical channel ID and a packet identification number included in the ACK # 2 signal 410, and determines the second channel. In order to transmit packet # 4 (412), which is the next packet, the second channel is set to the logical channel ID of the downlink map message and the packet # 3 412 attached to the downlink map message is transmitted to the PSS 210. Activate the timer for the second channel.

Since the wireless channel used by the mobile Internet network 220 frequently changes in channel state, the channel state suddenly becomes weak, or the channel state remains bad for a long time. May not receive packets from Alternatively, the PSS 210 transmits an ACK signal by receiving a packet from the RAS 222 or transmits an NACK signal because it does not receive the packet, but the RAS 222 does not receive an ACK signal or a NACK signal from the PSS 210. It may be.

Here, RAS 220 sent packet # 3 408 but PSS 210 did not receive packet # 3 408 or PSS 210 did not receive ACK # 3 signal (not shown) or NACK # 3 signal. The present invention will be described on the assumption that there is a case in which RAS 222 is transmitted but no ACK # 3 signal (not shown) or NACK # 3 signal 414 is generated.                     

If the PSS 210 does not receive the packet # 3 408 and receives only the downlink map message, the PSS 210 generates a NACK # 3 signal 414 and transmits the generated NACK # 3 signal to the RAS 222. At this time, the RAS 222 receiving the NACK # 3 signal 414 from the PSS 210 transmits the packet # 3 416 back to the PSS 210 instead of the packet # 5 424.

In addition, the PSS 210 may not transmit the ACK # 3 signal (not shown) or the NACK # 3 signal 414 to the RAS 222 when not only the packet # 3 408 but also the downlink map message are not received. Wait for packet reception. At this time, the RAS 222 expires the timer operated while transmitting the packet # 3 408, and when the timer expires, the RAS 222 transmits the packet # 3 416 to the PSS 210 again.

In addition, the PSS 210 receives the packet # 3 408 and transmits an ACK # 3 signal (not shown), but the RAS 222 does not receive the ACK # 3 (not shown). The timer that was activated while sending packet # 3 408 expires, and when the timer expires, RAS 222 sends packet # 3 416 back to PSS 210. Through this process, even if an error occurs in data transmission due to changes in the environment of the wireless channel, the error can be corrected.

The RAS 222 transmits packet # 4 412 when receiving the ACK # 2 signal 410 from the PSS 210 and packet # 6 420 when receiving the ACK # 4 418. In addition, the RAS 222 transmits the packet # 6 424 upon receiving the ACK # 3 signal 422 from the PSS 210 after transmitting the packet # 3 416 again.

As described above, in the process of describing the two-channel ARQ according to the preferred embodiment of the present invention, packets are divided and described through the first channel and the second channel, but the transmission of the packet through the first channel and the packet through the second channel are described. The transmission is continuous in time. That is, the RAS 222 may transmit packet # 1 402, continue to send packet # 2 404, and immediately send packet # 4 412 if it receives ACK # 2 410 immediately. In case of receiving ACK # 1, the packet # 3 can be transmitted. That is, the RAS 222 continuously transmits packets in time, manages the first channel and the second channel separately, and transmits the packets according to a predetermined algorithm regardless of the order.

Through this, the present invention may not waste radio resources by transmitting a packet and waiting until an ACK signal is received, and even if only one packet having an error is transmitted even when the ACK signal is not received, the efficiency of packet transmission may be improved. It can be improved.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, it is possible to easily implement a system for buffer management and error control by reducing the excessive occurrence of retransmissions and performing only retransmission of the same packet in a wireless environment where errors frequently occur. Improved error control performance by promoting the use of efficient algorithms used in the Third Generation Partnership Project (3GPP) or 3GPP2, even in the 802 series of standards that define only physical and MAC protocols, such as Wireless Local Area Networks or portable Internet networks. And the convenience of the system implementation can be improved.

Claims (11)

High Speed Portable Internet Network (HPi), including a personal subscriber station (PSS: `` PSS '') and a radio access station (RAS: RAS) In the method of transmitting packet data between the PSS and the RAS in a WiBro: Wireless Broadband Internet Network, (a) when the packet data to be transmitted to the PSS is generated, packing the packet data into a plurality of packets and selecting any one of the plurality of packets to determine a transmission schedule packet; (b) dividing the traffic channel allocated to the PSS into a plurality of logical channels to transmit the transmission scheduled packet to the PSS through one of the plurality of logical channels and to the logical channel Starting a timer for the channel; (c) checking whether the PSS has received the packet and generating an acknowledgment signal according to a result of the packet transmission to the RAS through the logical channel receiving the packet; (d) determining whether or not the RAS has received the acknowledgment signal and determining a transmission schedule packet according to a result of the confirmation and determining whether the plurality of packets have been transmitted; And (e) proceeding to step (b) if the plurality of packets are not transmitted as a result of the determination of step (d); Packet data transmission method using a multi-channel ARQ in a portable Internet network comprising a. The method of claim 1, wherein step (b) comprises: (b1) configuring a downlink logical channel identification (DL MAP) in a downlink map (DL MAP) message; (b2) attaching the downlink map message to the transmission schedule packet; And (b3) sending the transmission scheduled packet to the PSS and starting the timer; Packet data transmission method using a multi-channel ARQ in a portable Internet network comprising a. The method of claim 1, wherein step (c) comprises: (c1) checking whether the PSS has received a packet; (c2) As a result of checking in the step (c1), when the packet is received, the PSS sets an uplink logical channel ID in an uplink map (UL MAP) message and attaches the uplink map message. Generating an acknowledgment (ACK) signal as an acknowledgment signal and transmitting it to the RAS; (c3) confirming whether the PSS has received the downlink map message when the packet is not received as a result of the checking of the step (c1); (c4) When the downlink map message is received as a result of checking in the step (c3), the PSS sets an uplink logical channel ID to the uplink map message and attaches the uplink map message to a non-acknowledge. Generating a signal as an acknowledgment signal and transmitting it to the RAS; And (c5) proceeding to step (c1) if the downlink map message is not received as a result of checking in step (c3); Packet data transmission method using a multi-channel ARQ in a portable Internet network comprising a. The method of claim 1, wherein step (d) (d1) confirming whether the confirmation signal has been received; (d2) confirming whether the acknowledgment signal is an ACK signal when the acknowledgment signal is received as a result of the acknowledgment of step (d1); (d3) If the acknowledgment signal of the step (d2) indicates that the acknowledgment signal is the ACK signal, the packet identification number included in the ACK signal is checked to determine a packet next to the packet identification number as the transmission scheduled packet. Doing; (d4) When the confirmation signal of step (d2) indicates that the confirmation signal is a NACK (Non Acknowledge) signal instead of the ACK signal, the packet identification number included in the NACK signal is checked to determine the packet of the packet identification number. Determining a transmission schedule packet; (d5) confirming whether or not the timer expires when the confirmation signal of step (d1) is not received; (d6) determining, as the transmission scheduled packet, the packet determined as the transmission scheduled packet in the step (a) when the timer expires as a result of the checking in the step (d5); (d7) proceeding to step (d1) if the timer has not expired as a result of checking in step (d5); And (d8) determining whether all of the plurality of packet data have been transmitted; Packet data transmission method using a multi-channel ARQ in a portable Internet network comprising a. The method of claim 1, wherein the packet data transmission method, The RAS transmits the plurality of packets to the PSS through the plurality of logical channels, and transmits any one of the plurality of packets through any one of the plurality of logical channels and the one of the plurality of logical channels. Transmitting the other one of the plurality of packets through any one logical channel of the plurality of logical channels for a time until the acknowledgment signal is received through the same logical channel as the logical channel. Packet data transmission method using multi-channel ARQ in portable Internet network. The method of claim 1, wherein the plurality of logical channels, It is divided into two logical channels, and is inserted as a logical channel ID of 1 bit in a downlink map (DL MAP) message and an uplink map (UL MAP) message. Packet data transmission method using a multi-channel ARQ in a portable Internet network, characterized in that set. In a system for transmitting packet data to a personal subscriber station (PSS) via a wireless channel in a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network). , Packing the packet data into a plurality of packets, logically dividing a traffic channel as a plurality of logical channels, transmitting the plurality of packets to the PSS through the plurality of logical channels, and A radio access station which determines whether to send a packet according to a result of checking and confirming whether or not a confirmation signal has been received from RAS: Radio Access Station, hereinafter referred to as RAS) Packet data transmission system using a multi-channel ARQ in a portable Internet network comprising a. The method of claim 7, wherein the RAS, Transmit the plurality of packets to the PSS through the plurality of logical channels, and transmit any one packet of the plurality of packets through any one logical channel of the plurality of logical channels and The portable Internet network, wherein the other one of the plurality of packets is transmitted through any one of the plurality of logical channels for a time until the acknowledgment signal is received through the same logical channel. Packet data transmission system using multi-channel ARQ. The method of claim 7, wherein the plurality of logical channels, A multi-channel ARQ in a portable Internet network, which is divided into two logical channels and is inserted and set as a logical channel ID having a size of 1 bit in a DL MAP (Down Link Map) message. Packet data transmission system using. Includes multiple packets from a radio access station (RAS), via a wireless channel, using a portable Internet network (HPi: High Speed Portable Internet Network or WiBro: Wireless Broadband Internet Network) In a terminal for receiving packet data, First acknowledgment means for confirming whether or not the packet has been received; As a result of confirming by the first checking means, when the packet is received, an uplink logical channel ID (UL MAP) is set in an uplink map (UL MAP) message, and the ACK attaches the uplink map message. Transmitting means for generating an acknowledgment signal as an acknowledgment signal and transmitting it to the RAS; Second confirmation means for confirming whether or not a DL MAP message has been received when the packet is not received as a result of the confirmation by the first confirmation means; As a result of confirming by the second acknowledgment means, when the downlink map message is received, an uplink logical channel ID is set in the uplink map message and a non-acknowledge (NACK) signal to which the uplink map message is attached as an acknowledgment signal. Second transmission means for generating and transmitting to the RAS; And Third confirmation means for confirming whether or not the packet is received when the downlink map message is not received as a result of the confirmation by the second confirmation means; Personal Subscriber Station (PSS) for receiving packet data using a multi-channel ARQ in a portable Internet network comprising a series of processes including The method of claim 10, wherein the personal subscriber station, The individual subscriber to receive the packet data using the multi-channel ARQ in the portable Internet network, characterized in that the uplink logical channel ID is set to the same logical channel ID as the downlink logical channel ID of the downlink map message received from the RAS. terminal.

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