WO2016056684A1 - Method and apparatus for recovering from errors of terminal in heterogeneous network system - Google Patents

Abstract

Disclosed are a method and an apparatus for recovering from errors of a terminal in a heterogeneous network system. A process for recovering from an error of a block ACK operation may comprise the steps of: an STA establishing, through an AP, a cellular coordination error recovery process based on a cellular network object for the block ACK operation; and transmitting a DELBA message to the cellular network object, when the STA has not received a block ACK for a transmitted data unit in a time-out duration of a stop timer.

Description

Method and device for error recovery of terminal in heterogeneous network system

The present invention relates to wireless communication, and more particularly, to a method and apparatus for error recovery of a terminal in a heterogeneous network system.

LTE-A based communication services can provide users with much faster speeds than wired Internet. Accordingly, the spread of user equipment that can receive IP-based services based on cellular networks such as LTE-A is increasing. The user is using IP (Internet Protocol) based services such as Voice over LTE (VoLTE) and video call through the user terminal. Recently, the proportion of LTE-A based wireless Internet services is expected to increase further.

In addition to LTE or LTE-A, wireless local area networks (WLANs), mobile World Interoperability for Microwave Access (WiMAX), and High Speed Downlink Packet Access (HSDPA), which vary in transmission speed, coverage per base station, mobility, and data usage costs. Various communication systems can be used as next generation mobile communication networks. That is, a plurality of radio access technologies (RATs) coexist and the user may select and access a network according to his or her preference or a surrounding communication environment.

Specifically, current mobile devices such as smart phones and smart pads have a long term evolution-advanced (LTE-A) and a wireless local area network (WLAN) interface at the same time. In addition, mobile carriers support wireless Internet services through Wi-Fi zones as well as 4G networks with wide coverage.

In providing a service to a terminal through the cellular network and the WLAN network, various parts such as handover and data offloading should be considered.

An object of the present invention to provide an error recovery method of a terminal in a heterogeneous network system.

Another object of the present invention is to provide an apparatus for performing error recovery of a terminal in a heterogeneous network system.

An error recovery procedure of a block acknowledgment (ACK) operation according to an aspect of the present invention for achieving the above object of the present invention is based on the cellular network entity for the STA (station) for the block ACK operation through an access point (AP) Setting a cellular coordination error recovery procedure and transmitting a delete block acknowledgement (DELBA) message to the cellular network entity when the STA does not receive a block ACK for the data unit transmitted during the timeout duration of the stop timer. It may include a step.

An STA (station) performing an error recovery procedure of a block acknowledgment (ACK) operation according to another aspect of the present invention for achieving the above object of the present invention is a radio frequency (RF) implemented to transmit or receive a radio signal. And a processor operatively coupled to the RF unit, wherein the processor establishes a cellular network entity based cellular coordination error recovery procedure for the block ACK operation through an access point (AP) and stops. If the block ACK for the data unit transmitted during the timeout duration of the timer is not received, it may be implemented to transmit a delete block acknowledgment (DELBA) message to the cellular network entity.

An error recovery capability of a terminal transmitting or receiving data may be improved based on a plurality of radio access technologies (RATs).

1 is a conceptual diagram illustrating a structure of a wireless local area network (WLAN).

2 is a diagram illustrating a layer architecture of a WLAN system supported by IEEE 802.11.

3 is a conceptual diagram illustrating an A-MSDU.

4 is a conceptual diagram illustrating an A-MPDU.

5 shows a block ACK operation.

6 is a conceptual diagram illustrating a direct link setup (DLS).

7 is a conceptual diagram illustrating a method for transmitting and / or receiving data based on a heterogeneous network system.

8 is a conceptual diagram illustrating interworking between a WLAN and a cellular network according to an embodiment of the present invention.

9 is a conceptual diagram illustrating a method of managing AP information according to an embodiment of the present invention.

10 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a block ACK operation according to an embodiment of the present invention.

11 is a conceptual diagram illustrating an ADDBA request frame according to an embodiment of the present invention.

12 is a conceptual diagram illustrating a cellular adjustment error recovery request frame according to an embodiment of the present invention.

13 is a conceptual diagram illustrating an ADDBA response frame according to an embodiment of the present invention.

14 is a conceptual diagram illustrating a cellular adjustment error recovery response frame according to an embodiment of the present invention.

15 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a block ACK operation according to an embodiment of the present invention.

16 is a conceptual diagram illustrating an error recovery procedure associated with a block ACK operation according to an embodiment of the present invention.

17 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a DLS operation according to an embodiment of the present invention.

18 is a conceptual diagram illustrating a DLS request frame according to an embodiment of the present invention.

19 is a conceptual diagram illustrating a DLS response frame according to an embodiment of the present invention.

20 is a conceptual diagram illustrating a method for requesting setting of an error recovery procedure relating to a DLS operation according to an embodiment of the present invention.

21 is a conceptual diagram illustrating an error recovery procedure associated with a DLS operation according to an embodiment of the present invention.

22 is a block diagram illustrating a wireless device to which an embodiment of the present invention can be applied.

1 is a conceptual diagram illustrating a structure of a wireless local area network (WLAN).

1 shows the structure of an infrastructure BSS (Basic Service Set) of the Institute of Electrical and Electronic Engineers (IEEE) 802.11.

Referring to the top of FIG. 1, the WLAN system may include one or more infrastructure BSSs 100 and 105 (hereinafter, BSS). The BSSs 100 and 105 are a set of APs and STAs such as an access point 125 and a STA1 (station 100-1) capable of successfully synchronizing and communicating with each other, and do not indicate a specific area. The BSS 105 may include one or more joinable STAs 105-1 and 105-2 to one AP 130.

The BSS may include at least one STA, APs 125 and 130 that provide a distribution service, and a distribution system DS that connects a plurality of APs.

The distributed system 110 may connect several BSSs 100 and 105 to implement an extended service set (ESS) 140 which is an extended service set. The ESS 140 may be used as a term indicating one network in which one or several APs 125 and 230 are connected through the distributed system 110. APs included in one ESS 140 may have the same service set identification (SSID).

The portal 120 may serve as a bridge for connecting the WLAN network (IEEE 802.11) with another network (for example, 802.X).

In the BSS as shown in the upper part of FIG. 1, a network between the APs 125 and 130 and a network between the APs 125 and 130 and the STAs 100-1, 105-1 and 105-2 may be implemented. However, it may be possible to perform communication by setting up a network even between STAs without the APs 125 and 130. A network that performs communication by establishing a network even between STAs without APs 125 and 130 is defined as an ad-hoc network or an independent basic service set (BSS).

1 is a conceptual diagram illustrating an IBSS.

Referring to the bottom of FIG. 1, the IBSS is a BSS operating in an ad-hoc mode. Since IBSS does not contain an AP, there is no centralized management entity. That is, in the IBSS, the STAs 150-1, 150-2, 150-3, 155-4, and 155-5 are managed in a distributed manner. In the IBSS, all STAs 150-1, 150-2, 150-3, 155-4, and 155-5 may be mobile STAs, and access to a distributed system is not allowed, thus making a self-contained network. network).

A STA is any functional medium that includes a medium access control (MAC) and physical layer interface to a wireless medium that conforms to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. May be used to mean both an AP and a non-AP STA (Non-AP Station).

The STA may include a mobile terminal, a wireless device, a wireless transmit / receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile subscriber unit ( It may also be called various names such as a mobile subscriber unit or simply a user.

2 is a diagram illustrating a layer architecture of a WLAN system supported by IEEE 802.11.

2 conceptually illustrates a PHY architecture of a WLAN system.

The hierarchical architecture of the WLAN system may include a medium access control (MAC) sublayer 220, a physical layer convergence procedure (PLCP) sublayer 210, and a physical medium dependent (PMD) sublayer 200. have. The PLCP sublayer 210 is implemented such that the MAC sublayer 220 can operate with a minimum dependency on the PMD sublayer 200. The PMD sublayer 200 may serve as a transmission interface for transmitting and receiving data between a plurality of STAs.

The MAC sublayer 220, the PLCP sublayer 210, and the PMD sublayer 200 may conceptually include a management entity.

The management unit of the MAC sublayer 220 is referred to as a MAC Layer Management Entity (MLME) 225, and the management unit of the physical layer is referred to as a PHY Layer Management Entity (PLME) 215. Such management units may provide an interface on which layer management operations are performed. The PLME 215 may be connected to the MLME 225 to perform management operations of the PLCP sublayer 210 and the PMD sublayer 200, and the MLME 225 may also be connected to the PLME 215 and connected to the MAC. A management operation of the sublayer 220 may be performed.

In order for the correct MAC layer operation to be performed, there may be an STA management entity (SME) 250. SME 250 may operate as a component independent of the layer. The MLME, PLME, and SME may transmit and receive information between mutual components based on primitives.

The operation of each sub-layer is briefly described as follows. The PLCP sublayer 110 may convert the MAC Protocol Data Unit (MPDU) received from the MAC sublayer 220 according to the indication of the MAC layer between the MAC sublayer 220 and the PMD sublayer 200. Or a frame coming from the PMD sublayer 200 to the MAC sublayer 220. The PMD sublayer 200 may be a PLCP lower layer to perform data transmission and reception between a plurality of STAs over a wireless medium. The MAC protocol data unit (MPDU) delivered by the MAC sublayer 220 is called a physical service data unit (PSDU) in the PLCP sublayer 210. The MPDU is similar to the PSDU. However, when an A-MPDU (aggregated MPDU) that aggregates a plurality of MPDUs is delivered, the individual MPDUs and the PSDUs may be different from each other.

The PLCP sublayer 210 adds an additional field including information required by the physical layer transceiver in the process of receiving the PSDU from the MAC sublayer 220 to the PMD sublayer 200. In this case, the added field may include a PLCP preamble, a PLCP header, and tail bits required to return the convolutional encoder to a zero state in the PSDU. The PLCP preamble may serve to prepare the receiver for synchronization and antenna diversity before the PSDU is transmitted. The data field may include a coded sequence encoded with a padding bits, a service field including a bit sequence for initializing a scraper, and a bit sequence appended with tail bits in the PSDU. In this case, the encoding scheme may be selected from either binary convolutional coding (BCC) encoding or low density parity check (LDPC) encoding according to the encoding scheme supported by the STA receiving the PPDU. The PLCP header may include a field including information on a PLC Protocol Data Unit (PPDU) to be transmitted.

The PLCP sublayer 210 adds the above-described fields to the PSDU, generates a PPDU (PLCP Protocol Data Unit), and transmits it to the receiving station via the PMD sublayer 200, and the receiving station receives the PPDU to receive the PLCP preamble and PLCP. Obtain and restore information necessary for data restoration from the header.

3 is a conceptual diagram illustrating an A-MSDU.

Referring to FIG. 3, one of a method of aggregating data frames in order to reduce MAC error overhead in IEEE 802.11n, and the MAC service data unit (MSDU) 300 generated in the application layer is selected from the MAC layer. It can be gathered near the top and created as one MSDU. This may be defined as an aggregate-MSDU (A-MSDU) 350. In the A-MSDU 350, a plurality of MSDUs 300 having the same priority and having the same receiver address (RA) may be aggregated.

Each MSDU 300 may include a subframe header consisting of a destination address, a source address, and an MSDU length. The A-MSDU subframe may be padded such that the total length of the A-MSDU subframe is a constant multiple (multiple of 4 octets). These A-MSDU subframes are gathered to form one A-MSDU 350.

The A-MSDU 350 may be formed and transmitted as a single QoS data MAC protocol data unit (MPDU) without performing fragmentation unlike a single MSDU. The A-MSDU 350 may transmit only when the HT capability of the management information base (MIB) field is TRUE, that is, the HT STA, and may be transmitted only to the HT STA likewise. In the case of the HT STA, the A-MSDU 350 has the capability of de-aggregating the HT STA, and the HT STA determines whether the A-MSDU 350 is present in the QoS field of the MAC header of the received QoS data. You can check and perform the deaggregation.

When the ACK policy of the QoS data MPDU of the HT STA is set to normal ACK, the A-MSDU 300 may not be aggregated into the A-MPDU. In addition, whether the A-MSDU 300 can be aggregated into the A-MPDU may vary depending on whether a block acknowledgment agreement for each traffic identifier (TID) is made. Also, even when a block ACK agreement is made for the TID, the A-MSDU block ACK support indicator of the ADDBA acknowledgment response frame according to the ADDBA request frame adds a block ACK. If not indicated, A-MSDU may not be included in A-MPDU.

4 is a conceptual diagram illustrating an A-MPDU.

Referring to FIG. 4, a plurality of MPDUs 400 having the same receiver address (RA), a TID, and an ACK policy may be collected under the MAC layer to form an A-MPDU 450 as one PPDU.

The A-MPDU 450 is composed of one or more A-MPDU subframes, and each A-MPDU subframe may include an MPDU delimiter and an MPDU 400. The MPDU delimiter may be used to determine whether an error occurs in the A-MPDU subframe constituting the A-MPDU 450. The plurality of A-MPDU subframes may form one A-MPDU 450.

Successful reception of the A-MPDU 450 may be indicated based on the block ACK. The A-MPDU 450 may be formed only for the TID having the HT-immediate BA agreement, and the duration / ID field of the MPDU 400 constituting the A-MPDU 450 may be set. The value can be set equally.

5 shows a block ACK operation.

The block ACK mechanism has been introduced in order to acquire a transmission opportunity in IEEE 802.11e and to simultaneously transmit a response to a frame at the receiving side when transmitting several frames during the TXOP period. By using the block ACK mechanism, as in A-MSDU or A-MPDU, overhead can be reduced to improve the efficiency of the MAC layer.

Referring to FIG. 5, the block ACK transmission for the A-MPDU of one TID may include a setup process, a transmission process, and a tear down process.

The setup process may be a process of requesting and responding to a block ACK session.

The transmission process may transmit continuous data and receive an aggregated response to the continuous data.

A tear down process may release the established block ACK session.

In more detail, in the setting process, the transmitting side and the receiving side may transmit and receive each of the ADDBA request frame and the ADDBA response frame. In more detail, the transmitting side may transmit an ADDBA request frame, which is a management frame, to the receiving side. The ADDBA request frame may request a block ACK agreement for the current TID. The ADDBA request frame may transmit information on a block ACK policy type, a transmission buffer size of a transmitting side, a timeout value of a block ACK session, a starting sequence number (SSN), etc. to a receiving side. The receiving side receiving the ADDBA request frame may transmit the ADDBA response frame to the transmitting side in response to the ADDBA request frame. The ADDBA response frame may include a block ACK agreement state, an ACK policy, a buffer size, and a timeout value.

In the transmission process, the transmitting side may transmit the A-MPDU. When the transmission condition of the block ack request (BAR) frame for the A-MPDU is satisfied, the transmitting side may transmit the BAR frame to the receiving side. If the transmitting side of the A-MPDU is successful, the receiving side receiving the BAR frame may transmit a block ACK for the A-MPDU to the transmitting side.

The release process may be performed when the set timeout value of an inactivity timer set on the transmitting side and the receiving side expires or there is no more data to transmit for the corresponding TID. For example, in order to recover the block ACK error, a delete block acknowledgment (DELBA) frame may be transmitted to the receiving side or the transmitting side according to the expiration of the set timeout value of the stop timer, and the block ACK session may be terminated. When the transmitting side receives the block ACK, the stopping timer of the transmitting side may be reset. When the receiving side receives the MPDU, the block ACK request frame, the stop timer of the receiving side may be reset.

6 is a conceptual diagram illustrating a direct link setup (DLS).

The direct link establishment technique is an optional function of the IEEE 802.11e standard, and directly transmits and receives data frames between STAs. In case of using the direct link setup, the WLAN channel usage efficiency can be increased.

In order for an STA supporting direct link establishment to transmit or receive data through a direct link, the AP must support direct link establishment.

The STA1 may first transmit the DLS request frame 600 to the STA2 through the AP in order to directly transmit data to the STA2. After receiving the DLS request frame 600 from the STA1, the AP may transmit the DLS request frame 600 to the STA2. The STA2 may transmit the DLS response frame 650, which is a response to the DLS request frame 600, to the STA1 through the AP.

STA1 receiving the DLS response frame 650 may transmit a DLS configuration confirmation frame to STA2. After receiving the DLS configuration confirmation frame of STA2, the DLS configuration process may be completed.

Each of the DLS request frame 600 and the DLS response frame 650 may include information on supportable data transmission and reception rates of STA1 and STA2, respectively.

STA1 and STA2 may perform communication through the established direct link. In order to release the direct link between the STA1 and the STA2, the STA1 may transmit a DLS release request frame to the STA2. STA2 may transmit a DLS release response frame to STA1 in response to the received DLS release request frame.

The error recovery process for the direct link may be performed as follows.

STA1 and STA2 may use a DLS inactivity timer for error recovery for the direct link. The DLS Stop Timer may be reset for the transmission or reception of a successful frame on the direct link. The direct link may be inactive when there is no exchange of frames during the duration corresponding to the set DLS timeout value. If the direct link is stopped due to the DLS timeout value, the STA may send a DLS release frame to the AP. That is, when the set DLS timeout value of the set DLS stop timer expires, the error recovery process occurring on the direct link may be performed by canceling the direct link.

When the quality of the link between the AP and the STA or between the STA and the STA is inferior, the probability of error occurrence of the existing block ACK transmission and data transmission through the direct link is increased. If an error occurs, the STA or AP may perform a block ACK recovery procedure or a DLS recovery procedure. In the block ACK recovery procedure and the DLS recovery procedure, a completion time may vary according to a channel state between the AP and the STA and a channel access delay of the terminal. Errors of block ACK transmission and data transmission through the direct link may occur due to deterioration of the channel state between the STAs (Non-AP STA or AP STA). When the block ACK recovery procedure and the DLS recovery procedure are performed in the degraded channel state, the time taken for the ACK recovery procedure and the DLS recovery procedure may be long. Therefore, the transmission efficiency of the WLAN may be reduced.

Hereinafter, an embodiment of the present invention discloses a method for improving QoS of a WLAN based on a cellular-based recovery procedure. By performing a cellular-based recovery procedure according to an embodiment of the present invention it is possible to perform the recovery procedure faster than the conventional recovery procedure.

7 is a conceptual diagram illustrating a method for transmitting and / or receiving data based on a heterogeneous network system.

FIG. 7 illustrates interworking between a wireless LAN system and a cellular network (eg, an LTE system, an LTE-A system-based network, etc.) system among heterogeneous network systems (or a plurality of radio access technology (RAT) systems). A wireless communication method of an STA is disclosed.

Referring to FIG. 7, an STA may have a capability of accessing all eNBs of an AP cellular network of a WLAN. The STA may request a connection to a specific network in order to access a specific network of a WLAN and a cellular network. Although STAs can access each of the heterogeneous networks, they cannot access both heterogeneous networks at the same time.

The eNB may be connected to a serving gateway (S-GW) / mobility management entity (MME) via a cellular network interface. The MME has access information of the terminal or information on the capability of the terminal, and this information may be mainly used for mobility management of the terminal. The MME is responsible for the function of the control plane. S-GW is a gateway having an E-UTRAN as an endpoint. S-GW is in charge of the user plane. The S-GW / MME is also connected to a PDN (packet data network) gateway (P-GW) and a home subscriber server (HSS) via a cellular network interface. The PDN-GW is a gateway having a packet data network (PDN) as an endpoint.

In addition, the P-GW and HSS are connected with a 3GPP access authentication authorization (AAA) server through a cellular network interface. The P-GW and 3GPP AAA servers may be connected with an evolved packet data gateway (e-PDG) via a cellular network interface. e-PDG may only be included in untrusted non-3GPP connections. A WLAN access gateway (WAG) may play a role of P-GW in a WLAN system.

The communication on the heterogeneous network through the conventional WLAN and the cellular network was performed based on the request of the STA. In the conventional case, rather than direct interworking between the WLAN and the cellular network, a specific network server manages the WLAN information and requests based interworking of the STA of a method of performing handover between the WLAN and the cellular network at the request of the STA. Working was performed.

In addition, radio level control was not performed in communication on a heterogeneous network of STAs, and only network level flow mobility / IP-flow mapping was supported.

That is, in a conventional heterogeneous network, a connection for transmitting and / or receiving direct control information between a WLAN and a cellular network is not required. However, in order to increase the efficiency of the STA performing communication based on the WLAN and the cellular network, the communication on the heterogeneous network based on the direct interworking between the WLAN and the cellular network, rather than the communication on the heterogeneous network based on the request of the STA. This is necessary. When direct transmission and reception of control information between the WLAN and the cellular network is performed, efficient and fast interworking between the WLAN and the cellular network may be performed.

In addition, in the existing WLAN environment, there is a lack of consideration for an STA that fails to transmit an uplink frame.

Hereinafter, an embodiment of the present invention will be described assuming that a heterogeneous network (or a plurality of RATs) is a WLAN and a cellular network. However, a procedure for uplink transmission of a terminal according to an embodiment of the present invention may also be performed between different heterogeneous networks.

8 is a conceptual diagram illustrating interworking between a WLAN and a cellular network according to an embodiment of the present invention.

Referring to FIG. 8, offloading of data may be performed through interworking between the WLAN and the cellular network, and the maximum throughput of the data may be increased.

A cellular network based WLAN polling operation according to an embodiment of the present invention may be performed based on a connection between a WLAN and a cellular network as described below.

A wireless control connection 800 may be performed between the eNB and the AP. In addition, a wired control connection 850 may be performed through S-GW, P-GW, and ePDG of the EPC. The wired control connection 850 may be performed based on a new interface over a backbone network based on GPRS tunneling protocol (GTP) or a new protocol. The radio control connection 800 may be a connection between the eNB and the AP. The AP may support not only an 802.11 MAC / PHY layer for the wireless control connection 800, but also an LTE protocol stack for communication with the eNB.

According to an embodiment of the present invention, interworking between a WLAN and a cellular network may be directly performed in a core network such as an evolved packet core (EPC). That is, control information between the WLAN and the cellular network can be directly transmitted and received within the core network.

When the STA supports both the WLAN and the cellular network, the STA has a wide coverage, the cellular network system transmitting control information may be a primary system, and the WLAN system performing data transmission with a narrow coverage may be a secondary system.

When a cellular network based WLAN polling operation according to an embodiment of the present invention is performed, an entity associated with the cellular network may be used for interworking between the cellular network and the WLAN. For example, existing entities such as eNB, MME, P-GW can be used for interworking between cellular network and WLAN. Alternatively, a new entity for interworking between a cellular network and a WLAN, such as an InterWorking Management Entity (IWME) (not shown), may be defined in the core network.

An interworking function may be implemented in entities for interworking between heterogeneous networks. The interworking function may define a procedure for interworking between heterogeneous networks at the wireless network level and the core network level. An entity for interworking between heterogeneous networks may store and manage information related to an AP.

Hereinafter, it is assumed that the STA is a dual mode STA capable of supporting a WLAN and a cellular network.

9 is a conceptual diagram illustrating a method of managing AP information according to an embodiment of the present invention.

In FIG. 9, a method of controlling an AP of a WLAN and managing information about an AP in a cellular network is disclosed.

Referring to FIG. 9, an air interface between the eNB 900 and the AP 910 may be used for controlling the AP 910. The eNB 910 may control the AP 910 similarly to a general UE communicating with the eNB 900 based on a radio control connection between the AP 910.

Alternatively, the AP 910 may be controlled based on the backhaul interface between the eNB 900 and the AP 910. The eNB 900 may control the AP based on a wired control connection.

Alternatively, the AP 910 may be controlled based on a control interface between the MME 920 and the AP 910. The AP 910 may be controlled based on a control connection between the MME 920 and the AP 910 of the core network of the cellular network. Radio control connections between the eNB 900 and the AP 910 may also be used to control the AP based on the MME 920.

Alternatively, a control interface between the IWME 930 and the AP 910 may be used for the control of the AP 910.

In the exemplary embodiment of the present invention, the environment in which the eNB 900 and the AP 910 are not collocated is mentioned, but this is for convenience and is also proposed in the environment in which the eNB 900 and the AP 910 are collocated. The technique may be applicable.

Hereinafter, an embodiment of the present invention discloses a fast error recovery procedure related to a block ACK operation and a DLS operation.

In more detail, in relation to a block ACK operation, a configuration for cellular coordinated error recovery may be performed in advance when setting a block ACK or before / after setting a block ACK. If an error occurs in the block ACK operation based on this configuration, an error recovery procedure adjusted based on the cellular network may be performed.

In addition, in relation to the DLS operation, a setting for a cellular adjustment error recovery procedure may be performed in advance at the time of DLS setting or before / after DLS setting. Based on this configuration, if an error related to the DLS operation occurs, a cellular adjustment error recovery procedure may be performed.

By performing the cellular adjustment error recovery procedure instead of the block ACK recovery procedure and the DLS recovery procedure based on the WLAN, an error recovery procedure faster than the existing error recovery procedure can be performed.

Hereinafter, for convenience of description, the setting of the cellular adjustment error recovery procedure and the cellular adjustment error recovery procedure in the block ACK operation will be specifically described as STAs and APs for convenience of description, but STAs may be interpreted as APs and APs. The STA may be expressed in terms of an originator and an AP is a recipient.

In addition, the establishment of the cellular coordination error recovery procedure and the cellular coordination error recovery procedure in the block ACK operation may be performed between the STA that performs communication through the direct link and another STA. In addition, the cellular coordination error recovery procedure according to an embodiment of the present invention may be applied to various networks such as an infrastructure network, an ed-hoc network, and the like. The cellular coordination error recovery procedure may be performed in consideration of the channel state of the cellular network and / or WLAN.

10 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a block ACK operation according to an embodiment of the present invention.

The AP may request the IWME to configure a cellular coordination error recovery procedure when an error occurs between the AP and the STA in order to improve the QoS performance of the AP or another STA connected to the AP.

The cellular coordination error recovery procedure may be performed based on an entity of a cellular network such as eNB / MME / IWME as described above. Hereinafter, for convenience of description, it is assumed that a cellular adjustment error recovery procedure is performed based on the IWME.

Referring to FIG. 10, the STA may transmit an ADDBA request frame to the AP (step S1000).

The STA may determine information related to a block ACK operation before transmitting an add block acknowledgment (ADDBA) request frame. For example, a block ACK agreement may not exist between the STA and the AP. In this case, the STA may transmit the probe request frame and receive the block ACK operation information of the AP through the probe response frame. The block ACK operation information of the AP may include information about a delay block ACK of the AP, availability of an immediate block ACK, and availability of a block ACK operation of the AP.

The STA may determine whether to perform configuration of the cellular adjustment error recovery procedure based on the block ACK operation information of the AP. The STA may transmit an ADDBA request frame to the AP when it intends to perform configuration of a cellular adjustment error recovery procedure.

The ADDBA request frame sent by the STA may include a new field for requesting the AP to configure a cellular coordination error recovery procedure. The new field for requesting the establishment of this cellular coordination error recovery procedure may be a cellular coordination recovery field. The cellular adjustment error recovery field is described later.

Alternatively, the STA may request to configure a cellular adjustment error recovery procedure by transmitting a separately defined cellular adjustment error recovery request frame to the AP. Similarly, the cellular coordination error recovery request frame may include a cellular coordination error recovery field for requesting the establishment of a cellular coordination error recovery procedure.

The AP may send a cellular coordinated error recovery request message to the IWME for requesting the establishment of a cellular coordination error recovery request procedure (step S1010).

The AP may be requested to configure a block ACK operation and a cellular adjustment error recovery procedure from the STA. The AP may determine whether to set a block ACK operation and a cellular adjustment error recovery procedure.

If the AP determines the setting of the block ACK operation and the cellular adjustment error recovery procedure, the AP may send a cellular adjustment error recovery request message to the IWME.

On the contrary, the AP may not set the cellular adjustment error recovery procedure and only set the block ACK operation or the cellular adjustment error recovery procedure and the block ACK operation. In this case, the AP may transmit an ADDBA response frame including information on the inability to set the cellular adjustment error recovery procedure and / or the inability to set the block ACK operation to the STA.

The cellular coordination error recovery request message may be a message for requesting the IWME to set up a cellular coordination error recovery procedure. When the cellular coordination error recovery procedure is established, an error recovery procedure by a DELBA frame transmitted directly to the IWME by the STA through the cellular network may be performed. The cellular network based error recovery procedure will be described later.

For example, the cellular coordination error recovery request message sent by the AP is an indicator indicating that the cellular coordination error recovery request message, an identifier of the eNB (eg, an E-Utran Global Cell identifier (EGCI)), an identifier of the AP ( For example, SSID / BSSID), an identifier of the STA (eg, AID), an identifier of a peer STA in the direct link, indicating whether the cellular coordination recovery procedure relates to a block ACK operation or a DLS operation. It may include information of at least one of an indicator (eg, 1 if the cellular coordination error recovery procedure relates to a block ACK operation, 0 if the cellular coordination error recovery procedure relates to a DLS operation).

The cellular coordination error recovery request message may be sent to the IWME via the aforementioned wireless control connection (or wireless backhaul) or wired control connection (or wired backhaul).

The IWME may send a cellular coordinated error recovery response message to the AP (step S1020).

Upon receiving the cellular adjustment error recovery request message from the AP, the IWME may determine whether to set the cellular adjustment error recovery procedure.

If the setting of the cellular coordination error recovery procedure is determined, the IWME may send a cellular coordination error recovery response message to the AP. The cellular coordination error recovery response message is an indicator indicating the cellular coordination error recovery response message, an identifier of the eNB, an identifier of the AP (eg, SSID / BSSID), an identifier of the STA (eg, AID), a peer on the direct link. (peer) An identifier of the STA, an indicator indicating whether the cellular coordination error recovery procedure relates to a block ACK operation or a DLS operation (e.g., when the cellular coordination error recovery procedure relates to a block ACK operation 1, cellular If the coordination error recovery procedure relates to a DLS operation, it may include information of at least one of 0).

The IWME may decide not to perform the setup of the cellular adjustment error recovery procedure. In this case, the IWME may send a cellular coordinated error recovery failure message to the AP. The cellular coordination error recovery failure message may include information on why the cellular coordination error recovery procedure has been rejected.

The cellular coordination error recovery response message may be sent to the IWME via the aforementioned wireless control connection (or wireless backhaul) or wired control connection (or wired backhaul).

The AP may transmit an ADDBA response frame to the STA (step S1030).

The ADDBA response frame may include a new field (eg, a cellular coordination error recovery response field) for a response to a request for setting up a cellular coordination error recovery procedure as well as information related to a block ACK operation. The cellular adjustment error recovery response field may be included in a separately defined cellular adjustment error recovery response frame.

Through the above steps, the setting of the cellular network-based error recovery procedure may be completed through steps S1000 to S1030.

11 is a conceptual diagram illustrating an ADDBA request frame according to an embodiment of the present invention.

Referring to FIG. 11, the ADDBA request frame includes a category field 1100, a block ACK action field 1110, a dialog token field 1120, a block ACK parameter set field 1130, Block ACK timeout value field 1140, block ACK start sequence control field 1150, cellular coordinated error recovery request field 1160, and the like. have.

The category field 1100 may include information indicating a frame related to the block ACK.

The block ACK action field 1110 may include information indicating an ADDBA request frame.

The dialog token field 1120 may include a non-zero value.

The block ACK parameter set field 1130 includes information on whether the A-MSDU is supported, information on whether an immediate block ACK or a delayed block ACK is used as a block ACK policy, and information on a TID. It may include information on the buffer size available for a specific TID.

The block ACK timeout value field 1140 may include information about a time at which the setting of the block ACK ends.

The block ACK start sequence control field 1150 may include a sequence number of the first MSDU or A-MSDU for which block ACK is requested.

The cellular adjustment error recovery request field 1160 may include information on a cellular adjustment error recovery procedure. For example, the cellular coordination error recovery request field 1160 may include an indicator for requesting a cellular coordination error recovery procedure. As another example, the cellular coordination error recovery request field 1160 is composed of 2 bits, '00' indicates that the cellular coordination error recovery procedure is not requested, and '01' denotes a request for the cellular coordination error recovery procedure for the block ACK operation, 10 'may indicate a request for a cellular based error recovery procedure for the DLS operation.

12 is a conceptual diagram illustrating a cellular adjustment error recovery request frame according to an embodiment of the present invention.

In FIG. 12, a cellular coordination error recovery request frame, which is transmitted from the STA to the AP to request the establishment of a cellular coordination error recovery procedure, is disclosed.

Referring to FIG. 12, the cellular coordination error recovery request frame may include an indicator field 1200, a peer identifier field 1210, and a cellular coordination error recovery request field 1220.

The indicator field 1200 may include information indicating a cellular adjustment error recovery request frame.

The peer identifier field 1210 may include information about an identifier (eg, MAC address) of an AP or peer STA that receives the cellular coordination error recovery request frame.

The cellular adjustment error recovery request field 1220 may include information about a cellular adjustment error recovery procedure. For example, the cellular coordination error recovery request field 1220 may include an indicator for requesting a cellular coordination error recovery procedure. As another example, the cellular coordination error recovery request field 1220 consists of 2 bits, '00' indicates that the cellular coordination error recovery procedure is not requested, and '01' is a request for the cellular coordination error recovery procedure for the block ACK operation, 10 'may indicate a request for a cellular coordination error recovery procedure for the DLS operation.

13 is a conceptual diagram illustrating an ADDBA response frame according to an embodiment of the present invention.

Referring to FIG. 13, the ADDBA response frame includes a category field 1300, a block ACK action field 1310, a dialog token field 1320, a status code field 1330, and a block ACK parameter set field 1340. , A block ACK timeout value field 1350, a cellular coordinated error recovery response field 1360, and the like.

The category field 1300 may include information indicating a frame related to the block ACK.

The block ACK action field 1310 may include information indicating an ADDBA response frame.

The dialog token field 1320 may include a value obtained by copying a value of the dialog token field of the ADDBA request frame.

The status code field 1330 may include information for indicating whether the requested operation is successful or information on the cause of the failure when the requested operation fails.

The block ACK parameter set field 1340 includes information on whether or not the A-MSDU is supported, information on which of the immediate block ACK and delayed block ACK are used as the block ACK policy, information on the TID, and information available for a specific TID. Information about the buffer size may be included.

The block ACK timeout value field 1350 may include information on the time at which the block ACK configuration ends.

The cellular adjustment error recovery response field 1360 may include information on the cellular adjustment error recovery procedure. For example, the cellular adjustment error recovery response field 1360 may include an indicator indicating whether the setting of the cellular adjustment error recovery procedure is successful. Or the cellular coordination error recovery response field 1360 is composed of 2 bits, '00' indicates failure of the cellular adjustment error recovery procedure, and '01' indicates successful completion of the cellular-based error recovery procedure for the block ACK operation. May indicate a successful establishment of the cellular based error recovery procedure for the DLS operation.

14 is a conceptual diagram illustrating a cellular adjustment error recovery response frame according to an embodiment of the present invention.

FIG. 14 discloses a cellular coordination error recovery response frame sent as a response to a cellular coordination error recovery request frame from an STA to an AP.

Referring to FIG. 14, the cellular coordination error recovery response frame may include an indicator field 1400, a peer identifier field 1410, and a cellular coordination error recovery response field 1420.

The indicator field 1400 may include information indicating a cellular adjustment error recovery response frame.

The peer identifier field 1410 may include information about the STA or AP that receives the cellular coordination error recovery response frame.

The cellular adjustment error recovery response field 1420 may include information on a cellular adjustment error recovery procedure. For example, the cellular adjustment error recovery response field 1420 may include an indicator indicating whether the setting of the cellular adjustment error recovery procedure is successful. Or the cellular coordination error recovery response field consists of 2 bits, '00' means that the cellular coordination error recovery procedure failed to set, '01' means the cellular-based error recovery procedure succeeds in setting the block ACK operation, and '10' indicates the DLS operation. Can indicate success in establishing a cellular based error recovery procedure for.

15 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a block ACK operation according to an embodiment of the present invention.

In FIG. 15, unlike the case of FIG. 10, the AP requests the IWME to configure the cellular coordination error recovery procedure before or after the configuration of the block ACK operation between the STA and the AP.

Referring to FIG. 15, a configuration of a cellular adjustment error recovery procedure may be performed in an information exchange and configuration step for interworking between a WLAN and a cellular network independently of the configuration of the Block ACK operation. Alternatively, when the STA connects to the WLAN or cellular network, setting of a cellular adjustment error recovery procedure may be performed.

That is, the AP may transmit a cellular adjustment error recovery request message to the IWME regardless of whether the ADDBA request frame is transmitted (step S1510).

The IWME may determine whether to set up a cellular adjustment error recovery procedure based on the cellular based error recovery request message. The AP may receive a cellular based error recovery response message from the IWME in response to the cellular adjustment error recovery request message (step S1520).

The AP may transmit information on whether the cellular network-based error recovery procedure is configured to the STA through the beacon frame or the probe response frame (step S1500).

For example, the beacon frame or probe response frame may include a cellular coordination error recovery indicator that indicates whether a cellular coordination error recovery procedure is set (ie, whether the cellular coordination error recovery procedure can be performed).

Thereafter, an ADDBA request frame and an ADDBA response frame for a block ACK operation may be transmitted and received between the STA and the AP (step S1530).

The ADDBA request frame and the ADDBA response frame may use an existing defined frame, but may also include a cellular adjustment error recovery request field / cellular adjustment error recovery response field as described above. According to another embodiment of the present invention, the transmission and reception procedure of the cellular adjustment error recovery request frame and the cellular adjustment error recovery response frame may be performed after the transmission and reception procedure of the ADDBA request frame and the ADDBA response frame.

16 is a conceptual diagram illustrating an error recovery procedure associated with a block ACK operation according to an embodiment of the present invention.

In FIG. 16, a cellular adjustment error recovery procedure performed when an error relating to a block ACK operation occurs after an error recovery procedure relating to a block ACK operation is set.

According to an embodiment of the present invention, a stop timer for the cellular adjustment error recovery procedure may be additionally set. The stop timer for cellular coordination error recovery procedure may be expressed in terms of cellular coordination stop timer.

For example, the timeout value of the cellular adjustment stop timer may be set through the timeout value field of the ADDBA request frame or the ADDBA response frame.

The timeout value of the cellular adjustment stop timer may be set to a value smaller than the timeout value of the stop timer used in the conventional WLAN-based error recovery procedure. In this case, an error recovery procedure that is faster than an existing WLAN-based error recovery procedure may be performed.

The STA may determine whether to perform a cellular adjustment error recovery procedure based on the channel state between the combined AP and the STA. For example, when a value of a received signal to noise indicator (RSNI) of a signal transmitted from an AP is equal to or less than a predetermined threshold, the STA may determine to perform a cellular adjustment error recovery procedure. In addition, the STA may determine whether to transmit data through the cellular network or the WLAN.

The STA may transmit QoS data (eg, A-MPDU) to the AP (step S1600), and request a block ACK (BlockAckReq) to the AP (step S1610). The STA may receive a block ACK for QoS data from the AP.

If the STA does not receive the block ACK during the timeout duration of the cellular coordination stop timer, the STA may transmit a DELBA message to the IWME via the cellular network (step S1620).

The DELBA message includes an indicator indicating that the message is a DELBA message, an identifier of an AP, an identifier of an STA, an identifier of a peer STA, a set of DELBA parameters including information about a sender of a DELBA frame, and a reason for including an error reason. It may include a code field.

Upon receiving the DELBA message from the STA, the IWME may deliver the DELBA message to the AP based on the identifier of the AP included in the DELBA message or the identifier of the peer STA (step S1630).

The AP, having received the DELBA message from the IWME, may transmit a block ACK for the QoS data received from the STA to the STA through the cellular network or stop transmitting the block ACK.

When the AP sends a block ACK through the cellular network, the AP may send the block ACK to an entity (eg, IWME) of the cellular network. The entity of the cellular network may transmit the received block ACK to the STA.

17 is a conceptual diagram illustrating a method for requesting setting of a cellular adjustment error recovery procedure related to a DLS operation according to an embodiment of the present invention.

The AP may request the establishment of a cellular network based fast error recovery procedure when an error occurs in the direct link between the STA1 and the STA2 in order to improve the QoS performance between the STA1 and the STA2 connected by the direct link.

Referring to FIG. 17, the STA1 transmits a DLS request frame to the AP (step S1700).

The DLS request frame sent by STA1 may include a field (eg, a cellular coordination error recovery request field) for requesting the AP to set up a cellular coordination error recovery procedure. Alternatively, STA1 may request to configure a cellular adjustment error recovery procedure by transmitting a separate cellular adjustment error recovery request frame to the AP. The DLS request frame and the cellular coordination error recovery request frame transmitted by the STA to the AP will be described later.

Hereinafter, in the embodiment of the present invention, it is assumed that the STA transmits a DLS request frame including a new field for requesting setting of a cellular adjustment error recovery procedure.

The AP may send a cellular coordinated error recovery request message to the IWME for requesting the establishment of a cellular coordination error recovery request procedure (step S1710).

In FIG. 17, it is assumed that a cellular coordination error recovery procedure is performed based on the IWME, but a cellular coordination error recovery procedure may be performed based on another entity of a cellular network such as an eNB and an MME.

The AP may be requested to configure a cellular coordination error recovery procedure through the DLS request frame sent by STA1. The AP may determine whether to set up a cellular adjustment error recovery procedure.

If the AP determines to perform the setup of the cellular coordination error recovery procedure, the AP may send a cellular coordination error recovery request message to the IWME for requesting the establishment of the cellular coordination error recovery procedure.

On the contrary, if the AP decides not to perform the configuration of the cellular adjustment error recovery procedure, it may transmit only the DLS response frame to the STA1 without transmitting the cellular adjustment error recovery request message to the IWME.

The cellular adjustment error recovery request message may be a message for requesting setting of a cellular adjustment error recovery procedure. When the cellular coordination error recovery procedure is established, an error recovery procedure for the DLS operation may be performed based on the DLS release message sent directly to the IWME by the STA through the cellular network. The cellular adjustment error recovery procedure for the DLS operation will be described later.

For example, the cellular coordination error recovery request message sent by the AP is an indicator indicating the cellular coordination error recovery message, an identifier of the eNB (eg, an E-Utran Global Cell identifier (EGCI)), an identifier of the AP (eg For example, an SSID / BSSID), an indicator of STA1 (eg, AID), an identifier of STA2, a peer identifier, an indicator indicating whether a cellular-based recovery procedure is related to a block ACK operation or a DLS operation (eg, 1, when the cellular based recovery procedure relates to a block ACK operation, and 0) when the cellular based recovery procedure relates to a DLS operation.

The cellular coordination error recovery request message may be sent to the IWME via the aforementioned wireless control connection (or wireless backhaul) or wired control connection (or wired backhaul).

The IWME may send a cellular coordinated error recovery response message to the AP (step S1720).

Upon receiving the cellular adjustment error recovery request message from the AP, the IWME may determine whether to set the cellular adjustment error recovery procedure. If the setting of the cellular coordination error recovery procedure is determined, the IWME may send a cellular coordination error recovery response message to the AP. The cellular coordination error recovery response message is an indicator indicating that the message is a cellular coordination error recovery response message, an identifier of an eNB, an identifier of an AP (eg, SSID / BSSID), an identifier (eg, AID) of STA1, an STA Identifier, an indicator indicating whether the cellular based recovery procedure relates to a block ACK operation or to a DLS operation (eg, if the cellular based recovery procedure relates to a block ACK operation 1, If related, it may include at least one information of 0).

The IWME may decide not to perform the setup of the cellular adjustment error recovery procedure. In this case, the IWME may send a cellular coordinated error recover failure message to the AP. The cellular coordination error recovery failure message may include information on why the cellular coordination error recovery procedure has been rejected.

The cellular coordination error recovery response message may be sent to the IWME via the aforementioned wireless control connection (or wireless backhaul) or wired control connection (or wired backhaul).

The AP may transmit a DLS response frame to STA1 (step S1730).

The DLS response frame may include a new field (eg, a cellular coordination error recovery response field) as a response to the request for the establishment of the cellular coordination error recovery procedure as well as information related to the DLS operation. The response to the request for the establishment of the cellular coordination error recovery procedure may be performed through a separate cellular coordination error recovery response frame.

The DLS response frame and the cellular adjustment error recovery response frame transmitted by the AP to STA1 will be described later.

Through the above steps, the setting of the cellular adjustment error recovery procedure in the DLS operation may be completed through steps S1700 to S1730.

18 is a conceptual diagram illustrating a DLS request frame according to an embodiment of the present invention.

Referring to FIG. 18, the DLS request frame includes a category field 1800, a DLS action field 1810, a destination MAC address field 1820, a source MAC address field 1830, and a capability information field ( 1840, DLS timeout value field 1850, supported rate field 1860, extended supported rate field 1870, HT capability field 1880, cellular coordination error recovery request field ( 1890).

The category field 1800 may include information indicating a frame related to the DLS.

The DLS action field 1810 may include information for indicating a DLS request frame.

The destination MAC address field 1820 may include MAC address information of STA2.

The source MAC address field 1830 may include MAC address information of STA1.

The capability information field 1840 may include capability information of STA1.

The DLS timeout value field 1850 may include information about a timeout value for releasing a direct link.

The support rate field 1860 and the extended support rate field 1870 may include information about a rate supported by STA1.

The HT capability field 1880 may include information on the supportable HT capability of STA1.

The cellular adjustment error recovery request field 1890 may include information about a cellular adjustment error recovery procedure. For example, the cellular coordination error recovery request field 1890 may include an indicator for requesting a cellular coordination error recovery procedure. As another example, the cellular coordination error recovery request field 1890 consists of 2 bits, '00' is a non-request of the cellular coordination error recovery procedure, '01' is a request of the cellular coordination error recovery procedure for the block ACK operation, 10 'may indicate a request for a cellular coordination error recovery procedure for the DLS operation.

The cellular coordination error recovery request frame transmitted from STA1 to the AP to request the establishment of a cellular coordination error recovery procedure may have the same or similar frame format as that of FIG. 12.

19 is a conceptual diagram illustrating a DLS response frame according to an embodiment of the present invention.

Referring to FIG. 19, the DLS response frame includes a category field 1900, a DLS action field 1910, a destination MAC address field 1920, a source MAC address field 1930, a capability information field 1940, and a support rate field ( 1950, extended support rate field 1960, HT capability field 1970, and cellular adjustment error recovery response field 1980.

The category field 1900 may include information indicating a frame related to the DLS.

The DLS action field 1910 may include information for indicating a DLS request frame.

The destination MAC address field 1920 may include MAC address information of STA1.

The source MAC address field 1930 may include MAC address information of STA2.

The capability information field 1940 may include capability information of STA2.

The supported rate field 1950 and the extended supported rate field 1960 may include information about a rate supported by STA2.

The HT capability field 1970 may include information on the supportable HT capability of STA2.

The cellular adjustment error recovery response field 1980 may include information about the cellular adjustment error recovery procedure. For example, the cellular adjustment error recovery response field 1980 may include an indicator indicating whether the establishment of the cellular adjustment error recovery procedure is successful. Or the cellular coordination error recovery response field consists of 2 bits, '00' means that the cellular coordination error recovery procedure failed to set, '01' means the cellular-based error recovery procedure succeeds in setting the block ACK operation, and '10' indicates the DLS operation. Can indicate success in establishing a cellular based error recovery procedure for.

The cellular based recovery response frame sent as a response to the request of the establishment of the cellular coordination error recovery procedure from STA2 to the AP may have the same or similar frame format as FIG. 14.

20 is a conceptual diagram illustrating a method for requesting setting of an error recovery procedure relating to a DLS operation according to an embodiment of the present invention.

In FIG. 20, a case where a request for setting a cellular coordination error recovery procedure is requested before or after establishing a direct link between STA1 and STA 2 is described.

Referring to FIG. 20, a configuration of a cellular adjustment error recovery procedure may be performed in an information exchange and configuration step for interworking between a WLAN and a cellular network independently of the configuration of the DLS operation. Alternatively, when the STA connects to the WLAN or cellular network, setting of a cellular adjustment error recovery procedure may be performed (step S2000).

That is, the AP may transmit the cellular coordination error recovery request message to the IWME regardless of whether the DLS request frame is transmitted. The IWME may determine whether to configure a cellular coordination error recovery procedure based on the cellular coordination error recovery request message. If the setting of the cellular coordination error recovery procedure is determined, the IWME may send a cellular coordination error recovery response message.

The AP may inform the STA1 and the STA2 that the cellular adjustment error recovery procedure may be performed through the beacon frame or the probe response frame (step S2010).

For example, the beacon frame or probe response frame may include a cellular coordination recovery indicator indicating that the cellular coordination error recovery procedure may be performed.

Thereafter, the DLS request frame and the DLS response frame for the DLS operation may be transmitted and received between the STA1 and the STA2 (steps S2020 and S2030). The DLS request frame and the DLS response frame may use an existing defined frame, but may also include a cellular coordination recovery request field and a cellular coordination recovery response field as described above.

In addition, according to another embodiment of the present invention, the transmission and reception procedures of the cellular coordination recovery request frame and the cellular coordination recovery response frame may be performed after the DLS request frame and the DLS response frame.

21 is a conceptual diagram illustrating an error recovery procedure associated with a DLS operation according to an embodiment of the present invention.

FIG. 21 discloses a recovery procedure when an error related to a DLS operation occurs after the setting of an error recovery procedure related to a DLS operation.

If the frame is successfully transmitted or received over the direct link, the stop timer for the DLS operation may be reset. As described above, when the direct link is inactive during the timeout duration of the stop timer, the STA1 may transmit a DLS teardown frame to the IWME (step S2100). Receiving the DLS release frame, the IWME may transmit the DLS release frame to STA2 (step S2110).

STA1 may select a network for transmission of the DLS release message (or frame). The STA1 having received the cellular coordination error recovery procedure may determine whether to transmit a DLS release frame to STA2 through the WLAN or a DLS release message to the IWME via the cellular network when the direct link is deactivated during the timeout duration. .

The STA1 may transmit a DLS release message to the IWME through the cellular network in consideration of the channel state information of the cellular network and the channel state information of the WLAN. For example, the STA1 may transmit a DLS release message to the IWME through the cellular network when the value of channel information (eg, RSNI) between the AP and the STA1 is equal to or less than a predetermined threshold.

Upon receiving the DLS release message, the IWME may transfer the DLS release message to STA2. The DLS release message may include an indicator indicating the DLS release message, an identifier of the AP, an identifier of the STA2, an identifier of the STA1, a peer identifier, and information about the release reason.

The IWME sends a DLS release complete frame (or message) to the AP (step S2120).

When the DLS release is completed, the IWME may transmit a DLS release completion message to the AP. By the above-described procedure, the STA2 knows about the release of the direct link with the STA1. However, the AP may not know whether the direct link between the STA1 and the STA2 is released. In order for the AP to know the status of the direct link between the STA1 and the STA2 and manage the direct link, the AP may receive a DLS release complete frame or a DLS release complete message indicating that the direct link between the STA1 and the STA2 is released from the STA2 or the IWME.

The DLS release completion frame may include an indicator indicating that the message is a DLS release completion message, an identifier of the AP, an identifier of the STA2, an identifier of the IWME, and information about a reason for the DLS release.

The AP receives the DLS release complete frame from the STA2 through the WLAN, or the DLS via the wireless control connection (or wireless backhaul) or the wired control connection (or wired backhaul) described above from the IWME. You may also receive a release complete message. The AP may receive a DLS release complete message (or frame) and know about a direct link release between STA1 and STA2.

22 is a block diagram illustrating a wireless device to which an embodiment of the present invention can be applied.

Referring to FIG. 22, the wireless device 2200 may be an STA that may implement the above-described embodiment, and may be an AP 2200 or a non-AP STA (or STA) 2250.

The AP 2200 includes a processor 2210, a memory 2220, and an RF unit 2230.

The RF unit 2230 may be connected to the processor 2220 to transmit / receive a radio signal.

The processor 2220 may implement the functions, processes, and / or methods proposed in the present invention. For example, the processor 220 may be implemented to perform the operation of the wireless device according to the embodiment of the present invention described above. The processor may perform the operation of the wireless device disclosed in the embodiment of FIGS. 7 to 21.

For example, the processor 2220 may be implemented to send a cellular coordination error recovery request message to the IWME for requesting the establishment of a cellular coordination error recovery request procedure and to receive a cellular coordination error recovery response message from the IWME.

The STA 2250 includes a processor 2260, a memory 2270, and an RF unit 2280.

The RF unit 2280 may be connected to the processor 2260 to transmit / receive a radio signal.

The processor 2260 may implement the functions, processes, and / or methods proposed in the present invention. For example, the processor 2220 may be implemented to perform the operation of the wireless device according to the embodiment of the present invention described above. The processor may perform the operation of the wireless device in the embodiment of FIGS. 7 to 21.

For example, the processor 2260 sets a cellular network entity based cellular adjustment error recovery procedure for the block ACK operation through the AP, and does not receive a block ACK for the data unit transmitted during the timeout duration of the stop timer. If not, it may be implemented to send a delete block acknowledgment (DELBA) message to the cellular network entity.

Processors 2210 and 2260 may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, data processing devices, and / or converters for interconverting baseband signals and wireless signals. The memories 2220 and 2270 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices. The RF unit 2230 and 2280 may include one or more antennas for transmitting and / or receiving a radio signal.

When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) for performing the above-described function. The module may be stored in the memories 2220 and 2270 and executed by the processors 2210 and 2260. The memories 2220 and 2270 may be inside or outside the processors 2210 and 2260, and may be connected to the processors 2210 and 2260 by various well-known means.

Claims (8)

1. In an error recovery procedure of a block acknowledgment (ACK) operation,
   A station (STA) setting a cellular network entity based cellular coordination error recovery procedure for the block ACK operation through an access point (AP);
   And transmitting a delete block acknowledgement (DELBA) message to the cellular network entity if the STA does not receive a block ACK for the data unit transmitted during the timeout duration of the stop timer.
2. The method of claim 1, wherein setting up the cellular adjustment error recovery procedure comprises:
   Transmitting, by the STA, an add block acknowledgment (ADDBA) request frame to the AP; And
   The STA receiving an ADDBA response frame from the AP,
   The ADDBA request frame includes information for requesting setting of the cellular adjustment error recovery procedure,
   The ADDBA response frame includes information indicating whether the setting of the cellular adjustment error recovery procedure is successful.
3. The method of claim 1,
   The DELBA message is delivered to the AP via the cellular network entity,
   Wherein the block ACK is generated by the AP and retransmitted to the STA via the cellular network entity.
4. The method of claim 1,
   The STA performs the cellular adjustment error recovery procedure when the strength of the signal received from the AP is less than or equal to a threshold;
   When the strength of the signal received from the AP exceeds the threshold, the STA performs the AP-based error recovery procedure instead of the cellular adjustment error recovery procedure.
   The AP-based error recovery procedure transmits the DELBA message to the AP when the block ACK is not received during the timeout duration.
5. In an STA performing an error recovery procedure of a block acknowledgment (ACK) operation, the STA includes:
   A radio frequency (RF) unit implemented to transmit or receive a radio signal; And
   Includes a processor operatively connected to the RF unit,
   The processor establishes a cellular network entity based cellular coordination error recovery procedure for the block ACK operation through an access point (AP),
   And a STA configured to transmit a delete block acknowledgment (DELBA) message to the cellular network entity if a block ACK is not received for the data unit transmitted during the timeout duration of the stop timer.
6. The method of claim 5,
   The processor sends an add block acknowledgment (ADDBA) request frame to the AP to establish the cellular adjustment error recovery procedure,
   Is configured to receive an ADDBA response frame from the AP,
   The ADDBA request frame includes information for requesting setting of the cellular adjustment error recovery procedure,
   The ADDBA response frame includes information indicating whether the establishment of the cellular adjustment error recovery procedure is successful.
7. The method of claim 5,
   The DELBA message is delivered to the AP via the cellular network entity,
   Wherein the block ACK is generated by the AP and retransmitted to the STA via the cellular network entity.
8. The method of claim 5,
   The processor performs the cellular adjustment error recovery procedure when the strength of the signal received from the AP is less than or equal to a threshold;
   If the strength of the signal received from the AP exceeds the threshold, perform the AP-based error recovery procedure instead of the cellular adjustment error recovery procedure,
   The AP-based error recovery procedure transmits the DELBA message to the AP when the block ACK is not received during the timeout duration.

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