KR102351934B1 - Method and apparatus for transmitting and receiving data in wireless communication sytem - Google Patents

Abstract

According to the present invention, in order to receive data from a user device of a wireless communication system, it is determined whether a state of receiving data transmitted from a user terminal is a deadlock state, and when the state of receiving data is a deadlock state, a PDCP is reset and the present invention receives data from the user terminal based on a re-established PDCP entity. According to the present invention, the method and a base station for receiving data from the user terminal may be provided.

Description

Method and apparatus for transmitting and receiving data in a wireless communication system

The following embodiments relate to a technology for transmitting and receiving data of a wireless communication system, and more particularly, to a technology for transmitting and receiving data of a wireless communication system of a non-standalone (NSA) network.

Customers cannot use 5G network services due to data stall in 5G commercial networks. When a data stop phenomenon occurs, the user has to reboot the user terminal to solve the problem.

An embodiment may provide a method and a base station for receiving data from a user terminal.

According to one aspect, a method for receiving data, performed by a base station, includes: determining whether a state of receiving data transmitted from a user terminal of a wireless communication system is a deadlock state; , resetting a Packet Data Convergence Protocol (PDCP) - when the PDCP is reset, a PDCP entity is re-established - and receiving data from the user terminal based on the re-established PDCP entity. includes

The data may include Packet Data Convergence Protocol (PDCP) packets having a plurality of serial numbers.

The step of determining whether the data receiving state is a deadlock state may include operating a timer having a preset time when a packet received from the user terminal is discarded based on a serial number. determining whether at least one valid packet is received while the timer is running, and if at least one valid packet is not received until the timer expires, then the state of receiving the data is a deadlock. It may include the step of determining that

The step of determining whether at least one valid packet is received while the timer is running may include whether the target serial number of the target packet received from the user terminal is included in the target range of the serial number set in the window for receiving data. determining whether the target serial number is within the target range, determining the target packet as a valid packet, and if the target serial number is not within the target range, validating the target packet. It may include determining as a non-determined packet.

The resetting of the PDCP may include transmitting a message for resetting the PDCP to the user terminal, and receiving a PDCP reset completion message from the user terminal.

According to another aspect, the base station includes a memory in which a program for receiving data is recorded, and a processor for executing the program, wherein the program is deadlocked in a state of receiving data transmitted from a user terminal of a wireless communication system determining whether or not the state of receiving the data is deadlock, resetting a Packet Data Convergence Protocol (PDCP), if the PDCP is reset, a PDCP entity is re-established; and and receiving data from the user terminal based on the re-established PDCP entity.

The data may include Packet Data Convergence Protocol (PDCP) packets having a plurality of serial numbers.

The step of determining whether the data receiving state is a deadlock state may include operating a timer having a preset time when a packet received from the user terminal is discarded based on a serial number. determining whether at least one valid packet is received while the timer is running, and if at least one valid packet is not received until the timer expires, then the state of receiving the data is a deadlock. It may include the step of determining that

The step of determining whether at least one valid packet is received while the timer is running may include whether the target serial number of the target packet received from the user terminal is included in the target range of the serial number set in the window for receiving data. determining whether the target serial number is within the target range, determining the target packet as a valid packet, and if the target serial number is not within the target range, validating the target packet. It may include determining that the packet is not.

The resetting of the PDCP may include transmitting a message for resetting the PDCP to the user terminal, and receiving a PDCP reset completion message from the user terminal.

A method and a base station for receiving data from a user terminal may be provided.

1 is a block diagram of a wireless communication system for transmitting data to a user device through an NSA network according to an example.
2 illustrates a method for transmitting and receiving data to and from a user terminal through an SCG split bearer according to an example.
3 is a block diagram of a base station according to an embodiment.
4 is a flowchart of a data receiving method according to an embodiment.
5 is a flowchart of a method of determining whether a state of receiving data transmitted from a user terminal is a deadlock state according to an example;
6 is a flowchart of a method of determining whether to discard a packet based on a serial number of a received packet according to an example;
7 illustrates a case in which a state of receiving data according to an example is a deadlock state.
8 is a flowchart of a method for resetting PDCP according to an example.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these embodiments. Like reference numerals in each figure indicate like elements.

Various modifications may be made to the embodiments described below. It should be understood that the embodiments described below are not intended to limit the embodiments, and include all modifications, equivalents, and substitutes thereto.

Terms used in the examples are used only to describe specific examples, and are not intended to limit the examples. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are given the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

1 is a block diagram of a wireless communication system for transmitting data to a user device through an NSA network according to an example.

According to one aspect, a wireless communication system includes an Evolved Packet Core (EPC), an evolved Node B (eNB) 101 and a next generation Node B (gNB) 111 . For example, the eNB 101 may be a Long Term Evolution (LTE) standard base station, and the gNB 111 may be a 5G standard base station.

A method of providing a 5G standard wireless communication service includes a standalone (SA) method using only the gNB 111 and a non-standalone (NSA) method using both the eNB 101 and the gNB 111 .

The interface between the MME (Mobility Management Entity) of the EPC and the eNB 101, which is an LTE base station, is interlocked with an S1-C (or S1-MME) interface, and the interface between the S-GW of the EPC and the eNB 101 and the S- of the EPC The interface between the GW and the gNB 111 as the NR base station is interlocked with the S1-U interface. That is, the S1-C interface between the MME and the gNB 111 may not exist. The protocol of the interface between the gNB 111 and the eNB 101 may be interlocked using X2-U and X2AP. In a dual connectivity (EN-DC) environment of LTE and NR, the eNB 101 may be referred to as a Master Node (MN), and the gNB 111 may be referred to as a Secondary Node (SN).

According to one aspect, in order to transmit Packet Data Convergence Protocol (PDCP) data to the user equipment 120 in the EN-DC environment, paths connected to the user equipment 120 using a split bearer are established. can Efficient data transmission/reception with the user device 120 may be performed through the paths.

According to another aspect, when the UE 130 is located only within the coverage 102 of the eNB 101 and is located outside the coverage 112 of the gNB 111 , the EN-DC is not provided. In this case, the user equipment 130 may transmit and receive data only through the eNB 101 .

2 illustrates a method for transmitting and receiving data to and from a user terminal through an SCG split bearer according to an example.

According to one aspect, an L2 layer operation of a split bearer on a downlink basis is shown. For example, a plurality of packets of PDCP data may be distributed and transmitted through the eNB 210 and the gNB 220 according to data transmission scheduling.

3 is a block diagram of a base station according to an embodiment.

According to one aspect, the base station 300 includes a communication unit 310 , a processor 320 , and a memory 330 . For example, the base station 300 may be the eNB 101 or the gNB 111 described above with reference to FIG. 1 .

The communication unit 310 is connected to the processor 320 and the memory 330 to transmit and receive data. The communication unit 310 may be connected to another external device to transmit/receive data.

The communication unit 310 may be implemented as a circuit network within the base station 300 . For example, the communication unit 310 may include an internal bus and an external bus. As another example, the communication unit 310 may be an element connecting the base station 300 and an external device. The communication unit 310 may be an interface. The communication unit 310 may receive data from an external device and transmit the data to the processor 320 and the memory 330 .

The processor 320 processes data received by the communication unit 310 and data stored in the memory 330 . Processor 320 executes computer readable code (eg, software) stored in memory (eg, memory 330 ) and instructions issued by processor 320 .

The memory 330 stores data received by the communication unit 310 and data processed by the processor 320 . For example, the memory 330 may store a program (or an application, software). The stored program may be a set of syntax that is coded to receive data by resolving data deadlock and is executable by the processor 320 .

According to one aspect, memory 330 may include one or more of volatile memory, non-volatile memory and RAM, flash memory, hard disk drive, and optical disk drive.

The memory 330 stores an instruction set (eg, software) for operating the base station 300 . The instruction set for operating the base station 300 is executed by the processor 320 .

4 is a flowchart of a data receiving method according to an embodiment.

The following steps 410 to 430 may be performed by the base station 300 described above with reference to FIG. 3 .

In step 410, the base station 300 determines whether the state of receiving data transmitted from the user terminal is a deadlock state.

For example, a PDCP packet of a serial number that has already been received by the base station 300 is re-received, or a PDCP packet of a serial number that is not a reception target is received, and the corresponding PDCP packet may be discarded. . If this situation persists, a deadlock occurs in which no further data is received.

A method of determining whether a state of receiving data is a deadlock state will be described in detail below with reference to FIGS. 5 to 7 .

In step 420 , the base station 300 resets the PDCP when the data reception state is a deadlock state. When the PDCP is reset, a PDCP entity may be re-established. Resetting the PDCP may mean to empty the PDCP buffer and re-create the PDCP entity. The reset of the PDCP means resetting the PDCP of the base station 300 and the user terminal rather than reconnecting the user terminal to the wireless network.

A method of resetting the PDCP will be described in detail below with reference to FIG. 8 .

In step 430, the base station 300 receives data from the user terminal based on the re-established PDCP entity. When the PDCP is reset, when a PDCP packet of a serial number that was previously discarded due to a deadlock is re-received from the user terminal, it can be effectively received.

After the PDCP reset procedure, if the user terminal is within the coverage of the 5G network, the user terminal immediately transmits a 5G network addition request, and the base station 300 provides a 5G network service to the user terminal by performing the 5G network addition procedure.

If the user terminal is only within the coverage of the LTE network, since the user terminal does not transmit a 5G network addition request to the base station 300 , the service is provided only through the LTE network.

5 is a flowchart of a method of determining whether a state of receiving data transmitted from a user terminal is a deadlock state according to an example;

According to one aspect, the step 410 described above with reference to FIG. 4 may include the following steps 510 to 560 .

In step 510, the base station 300 determines whether to discard the packet based on the serial number of the packet received from the user terminal. For example, it may be determined whether a received packet is discarded based on a window for receiving data. A method of discarding a packet will be described below with reference to FIGS. 6 and 7 .

If the received packet is not discarded, step 520 is performed, and if the received packet is discarded, step 530 is performed.

In step 520, the base station 300 resets the timer if the packet is not discarded. For example, when the timer is running, the timer may be stopped and the timer may be reset. As another example, if the timer is not running, step 520 may not be performed.

In step 530, the base station 300 determines whether a timer is running when the packet is discarded. If the timer is not running, step 540 is performed, and if the timer is running, step 550 is performed.

In step 540, the base station 300 operates the timer if the timer is not running. The timer may have a preset time.

In step 550, when the timer is running, the base station 300 determines whether the timer has expired. If the timer has not expired, steps 510 and 520 described above may be re-performed.

In step 560, the base station 300 determines that the state of receiving data when the timer expires as a deadlock state.

6 is a flowchart of a method of determining whether to discard a packet based on a serial number of a received packet according to an example;

According to one aspect, the step 510 described above with reference to FIG. 5 may include the following steps 610 to 630 .

In step 610, the base station 300 determines whether the target serial number of the target packet received from the user terminal is included in the target range of the serial number set in the window for receiving data. The window is described in detail below with reference to FIG. 7 .

In step 620, when the target serial number is included in the target range, the base station 300 determines a valid target packet.

In step 630, when the target serial number is not included in the target range, the base station 300 determines the target packet as an invalid packet and discards it.

7 illustrates a case in which a state of receiving data according to an example is a deadlock state.

For example, the base station 300 orders packets having serial numbers "217543", "217544", "259503",????, "259582", "217545", and "217546" from the user terminal 700 . can be received as On the serial number, packets with "217545", "217546" serial numbers should be received before packets with "259503", ????, "259582" serial numbers, but for some reason they may be received later. The process of receiving the above packets may be described with the following steps 710 to 740 .

In step 710, when the base station 300 receives the SN 217543 and SN 217544 packets, the serial number range of the window for receiving data moves to 217545 to 262143. The serial number range is 2^ (PDCP serial number length-1).

In step 720, the base station 300 receives the SN 259503 packet, not the SN 217545 packet, so that a reordering timer is activated. If SN 217545 packets through SN 259582 packets are received while the reordering timer is running (ie before completion), then SN 217545 packets through SN 259582 packets are within the serial number range of the window and are valid packets and are not discarded.

In step 730, if the SN 217545 packet is not received before the reordering timer expires, the starting number of the serial number range of the window is moved to SN 259583.

In step 740, after the start number of the serial number range of the window is moved to SN 259583, even if the base station 300 receives the SN 217545 packet, it is discarded because it is outside the serial number range of the window. If the received packets are continuously discarded until the preset timer expires, the data receiving state is determined to be a deadlock state.

8 is a flowchart of a method for resetting PDCP according to an example.

According to one aspect, step 420 described above with reference to FIG. 4 may include steps 810 and 820 below.

In step 810, the base station 300 transmits a message for resetting the PDCP to the user terminal. For example, the message may be a PDCP reset related message information element (IE) in RRC connection reconfiguration. The message for resetting the PDCP may be a message IE defined in the 3GPP standard.

In step 820, the base station 300 receives a PDCP reset completion message from the user terminal. When the PDCP is reset, the PDCP entity is re-established.

The device described above may be implemented as a hardware component, a software component, and/or a combination of the hardware component and the software component. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For convenience of understanding, although one processing device is sometimes described as being used, one of ordinary skill in the art will recognize that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that can include For example, the processing device may include a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as parallel processors.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floppy disks. - includes magneto-optical media, and hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible from the above description by those skilled in the art. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

300: base station
310: communication unit
320: processor
330: memory

Claims (11)

A method of receiving data, performed by a base station, includes:
Determining whether a state of receiving data transmitted from a user terminal of a wireless communication system is a deadlock state - the data includes Packet Data Convergence Protocol (PDCP) packets having a plurality of serial numbers;
resetting a Packet Data Convergence Protocol (PDCP) when the reception state of the data is a deadlock state, when the PDCP is reset, a PDCP entity is re-established; and
receiving data from the user terminal based on the re-established PDCP entity;
including,
Determining whether the state of receiving the data is a deadlock state,
operating a timer having a preset time when the packet received from the user terminal is discarded based on the serial number;
determining whether a target serial number of a target packet received from the user terminal is included in a target range of a serial number set in a window for receiving data;
determining the target packet as a valid packet when the target serial number is within the target range;
determining the target packet as an invalid packet when the target serial number is not included in the target range; and
determining that the state of receiving the data is a deadlock if at least one valid packet is not received until the timer expires;
containing,
How to receive data.
delete delete delete According to claim 1,
The step of resetting the PDCP comprises:
transmitting a message for resetting the PDCP to the user terminal; and
Receiving a PDCP reset completion message from the user terminal
containing,
How to receive data.
A computer-readable recording medium containing a program for performing the method of any one of claims 1 and 5.
base station,
a memory in which a program for receiving data is recorded; and
a processor that executes the program
including,
The program is
Determining whether a state of receiving data transmitted from a user terminal of a wireless communication system is a deadlock state - the data includes Packet Data Convergence Protocol (PDCP) packets having a plurality of serial numbers;
resetting a Packet Data Convergence Protocol (PDCP) when the reception state of the data is a deadlock state, when the PDCP is reset, a PDCP entity is re-established; and
receiving data from the user terminal based on the re-established PDCP entity;
do,
Determining whether the state of receiving the data is a deadlock state comprises:
operating a timer having a preset time when the packet received from the user terminal is discarded based on the serial number;
determining whether a target serial number of a target packet received from the user terminal is included in a target range of a serial number set in a window for receiving data;
determining the target packet as a valid packet when the target serial number is within the target range;
determining the target packet as an invalid packet when the target serial number is not included in the target range; and
determining that the state of receiving the data is a deadlock if at least one valid packet is not received until the timer expires;
containing,
base station.
delete delete delete 8. The method of claim 7,
The step of resetting the PDCP comprises:
transmitting a message for resetting the PDCP to the user terminal; and
Receiving a PDCP reset completion message from the user terminal
containing,
base station.

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