WO2024093104A1

WO2024093104A1 - Terminal device, network device and methods for multi-path communications

Info

Publication number: WO2024093104A1
Application number: PCT/CN2023/084195
Authority: WO
Inventors: Ran YUE; Lianhai WU; Haiming Wang; Jing HAN; Min Xu; Jie Hu
Original assignee: Lenovo (Beijing) Limited
Priority date: 2023-03-27
Filing date: 2023-03-27
Publication date: 2024-05-10

Abstract

Embodiments of the present disclosure relate to a solution for MP communications. In one aspect of the solution, a terminal device determines that at least one condition associated with update of at least one of multiple paths for MP operation is satisfied. The terminal device also determines an occasion associated with the update of the at least one of multiple paths. In turn, the terminal device controls, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.

Description

TERMINAL DEVICE, NETWORK DEVICE AND METHODS FOR MULTI-PATH COMMUNICATIONS

FIELD

Embodiments of the present disclosure generally relate to the field of communication, and in particular to terminal device, network device and methods for multi-path (MP) communications.

BACKGROUND

As the number of mobile devices within wireless networks and the demand for mobile data traffic continue to increase, changes are made to system requirements and architectures to better address current and anticipated demands. For example, some wireless communication networks (e.g., fifth generation (5G) or new radio (NR) networks) may be developed to include user equipment (UE) to network (NW) (U2N) relay communications. In such scenarios, a timer associated with access control needs to be controlled.

SUMMARY

In general, embodiments of the present disclosure provide a solution for MP (multiple paths) communications.

In a first aspect, there is provided a terminal device. The terminal device comprises a processor and a transceiver coupled to the processor. The processor is configured to: determine that at least one condition associated with update of at least one of multiple paths for MP operation is satisfied; determine an occasion associated with the update of the at least one of multiple paths; and control, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.

In a second aspect, there is provided a network device. The network device comprises a processor and a transceiver coupled to the processor. The processor is configured to: determine to update at least one of multiple paths for MP operation; and transmit, via the transceiver to a terminal device, a signaling for the update.

In a third aspect, there is provided a method performed by a terminal device. The method comprises: determining, at a terminal device, that at least one condition associated with update of at least one of multiple paths for multi-path operation is satisfied; determining an occasion associated with the update of the at least one of multiple paths; and controlling, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.

In a fourth aspect, there is provided a method performed by a network device. The method comprises: determining, at a network device, to update at least one of multiple paths for multi-path operation; and transmitting, to a terminal device, a signaling for the update.

In a fifth aspect, there is provided a computer readable medium. The computer readable medium has instructions stored thereon. The instructions, when executed on at least one processor of a device, causing the device to perform the method of the third aspect or the fourth aspect.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments will now be described with reference to the accompanying drawings in which:

Figs. 1A, 1B, 1C, 1D, 1E, 1F and 1G illustrate a schematic diagram of a communication environment in which some embodiments of the present disclosure can be implemented, respectively;

Fig. 2 illustrates a flowchart of a method implemented at a terminal device in accordance with some embodiments of the present disclosure;

Fig. 3 illustrates a flowchart of a method implemented at a network device in accordance with other embodiments of the present disclosure; and

Fig. 4 illustrates a simplified block diagram of an apparatus that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar elements.

DETAILED DESCRIPTION

Principles of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below. In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms. In some examples, values, procedures, or apparatuses are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of embodiments. As used herein, the singular forms “a, ” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises, ” “comprising, ” “has, ” “having, ” “includes” and/or “including, ” when used herein, specify the presence of stated features, elements, components and/or the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. For example, the term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The use of an expression such as “A and/or B” can mean either “only A” or “only B” or “both A and B. ” Other definitions, explicit and implicit, may be included below.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as, 5G NR, Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) , and so on. Further, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) , the sixth generation (6G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will also be future type communication technologies and systems in which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned systems.

As used herein, the term “network device” generally refers to a node in a communication network via which a terminal device can access the communication network and receive services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , a radio access network (RAN) node, an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , an infrastructure device for a V2X (vehicle-to-everything) communication, a transmission and reception point (TRP) , a reception point (RP) , a remote radio head (RRH) , a relay, an integrated access and backhaul (IAB) node, a low power node such as a femto BS, a pico BS, and so forth, depending on the applied terminology and technology.

As used herein, the term “terminal device” generally refers to any end device that may be capable of wireless communications. By way of example rather than a limitation, a terminal device may also be referred to as a communication device, a user equipment (UE) , an end user device, a subscriber station (SS) , an unmanned aerial vehicle (UAV) , a portable subscriber station, a mobile station (MS) , or an access terminal (AT) . The terminal device may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet, a wearable terminal device, a personal digital assistant (PDA) , a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a gaming terminal device, a music storage and playback appliance, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , a USB dongle, a smart device, wireless customer-premises equipment (CPE) , an Internet of Things (IoT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device (for example, a remote surgery device) , an industrial device (for example, a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms: “terminal device, ” “communication device, ” “terminal, ” “user equipment” and “UE, ” may be used interchangeably.

Figs. 1A, 1B, 1C and 1D illustrate schematic diagrams of communication environments 100A, 100B, 100C and 100D in which some embodiments of the present disclosure can be implemented. Each of the communication environments 100A, 100B, 100C and 100D may comprise a terminal device 110, a network device 120, and a terminal device 130. Hereinafter, the terminal devices 110 and 130 may also be referred to as the UE 110 and UE 130, respectively.

The terminal device 110 may be in coverage of a cell 122 of the network device 120. In this case, the terminal device 110 may be connected to the network device 120 using a direct path 140. The cell 122 may be a serving cell on the direct path 140 for the terminal device 110.

In some embodiments, an interface between the terminal device 110 and the network device 120 may be a Uu interface.

As shown in Fig. 1A, in some embodiments, in order to extend cell coverage and provide reachability for cell-edge users (or out-of-coverage users) , an indirect path 150 may be established and added after the direct path 140 was established. Thus, the terminal device 110 may be connected to the network device 120 using the indirect path 150 via the terminal device 130. The terminal device 130 is in coverage of a cell 124 of the network device 120. In this case, the terminal device 130 is also referred to as a U2N relay UE, and the terminal device 110 is also referred to as a remote UE. The cell 124 may be a serving cell on the indirect path 150 for the terminal device 110.

It shall be understood that the cell 122 and the cell 124 can be the same cell or different cell.

In the present disclosure, a direct path may also be referred to as a direct link or direct leg, and an indirect path may also be referred to as an indirect link or indirect leg.

In some embodiments, an interface between the terminal device 130 and the network device 120 may be a Uu interface, and an interface between the terminal device 110 and the terminal device 130 may be a PC5 interface. In such embodiments, a connection between the terminal device 110 and the terminal device 130 may be a PC5-Radio Resource Control (RRC) connection.

As shown in Fig. 1B, in some embodiments, the direct path 140 may be established and added after the indirect path 150 was established.

In the communication environments 100A, 100B, 100C and 100D, the terminal device 110 may perform an MP operation. In other words, the terminal device 110 may operate with multiple paths which may comprise the direct path 140 and the indirect path 150, for example.

In some embodiments, during the MP operation, the terminal device 110 may communicate with the network device 120 using both the direct path 140 and the indirect path 150 concurrently. Alternatively, during the MP operation, the terminal device 110 may communicate with the network device 120 using one of the direct path 140 and the indirect path 150.

In some embodiments, the connection between the terminal device 110 and the terminal device 130 may be determined to be released. Thus, the indirect path 150 may be released, as shown in Fig. 1C.

In some embodiments, the connection between the terminal device 110 and the network device 120 may be determined to be released. Thus, the direct path 140 may be released, as shown in Fig. 1D. It shall be noted that the cells 122 and 124 are not illustrated in Fig. 1C and 1D for brevity.

Fig. 1E illustrates a schematic diagram of a communication environment 100E in which some embodiments of the present disclosure can be implemented.

The communication environment 100E is similar to the communication environments 100A, 100B, 100C and 100D.

The communication environment 100E is different from the communication environments 100A, 100B, 100C and 100D in that in the communication environment 100E, if the indirect path 150 is released, in order to maintain the MP operation, at least one candidate relay UE and at least one other indirect path may be established and added for the MP operation if a predetermined condition is met. The candidate relay UE may be in coverage of the cell 124 or out of coverage of the cell 124. It shall be noted that the cells 122 and 124 are not illustrated in Fig. 1E for brevity.

For example, the candidate relay UE may comprise a terminal device 132. The terminal device 132 may be in coverage of the cell 124 or out of coverage of the cell 124. If the predetermined condition is met, an indirect path 152 may be established and added for the MP operation. Thus, the terminal device 110 may be connected to the network device 120 using the indirect path 152 via the terminal device 132.

In some embodiments, the terminal device 110 may be connected to the network device 120 using multiple direct paths and multiple indirect paths. This will be described with reference to Figs. 1F and 1G.

Figs. 1F and 1G illustrate schematic diagrams of communication environments 100F and 100G in which some embodiments of the present disclosure can be implemented, respectively.

In the communication environments 100F and 100G, the terminal device 110 are connected to the network device 120 using direct paths 140 and 142 as well as indirect paths 150 and 152.

In some embodiments, after the direct path 140 as well as at least one of the indirect paths 150 and 152 were established for MP operation, the direct path 142 may be established and added for MP operation.

In some embodiments, the connection between the terminal device 110 and the terminal device 130 may be determined to be released. Thus, the indirect path 150 may be released.

Alternatively, in some embodiments, the connection between the terminal device 110 and the terminal device 132 and direct connections between the terminal device 110 and the network device 120 may be determined to be released while the connection between the terminal device 110 and the terminal device 130 may be determined to be maintained. Thus, the direct paths 140 and 142 as well as the indirect path 152 may be released while the indirect path 150 may be maintained. In other words, remaining paths among the multiple paths except the indirect path 150 may be released, as shown in Fig. 1G.

It is to be understood that the numbers of the network devices and terminal devices in Figs. 1A to 1G are only for ease of understanding without suggesting any limitations. Each of the communication environments 100A to 100G may include any suitable number or type of the network devices and terminal devices adapted for implementing embodiments of the present disclosure.

Communications in the communication environments 100A to 100G may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) , the fifth generation (5G) or the future sixth generation (6G) wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA) , Frequency Division Multiple Access (FDMA) , Time Division Multiple Access (TDMA) , Frequency Division Duplex (FDD) , Time Division Duplex (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiple (OFDM) , Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and/or any other technologies currently known or to be developed in the future.

In some embodiments, once a direct path (such as the direct path 140) is established, a cell which the terminal device 110 accessed (such as the cell 122) becomes a primary cell (PCell) of the terminal device 110 and a Cell-Radio Network Temporary Identifier (C-RNTI) of the terminal device 110 may be maintained in a Medium Access Control (MAC) entity of the terminal device 110.

In legacy, when a new session of a service is generated, UE in an RRC_CONNECTED state may perform a procedure of access control for the new session. The purpose of this procedure is to perform access barring check for an access attempt associated with an Access Category corresponding to the service and one or more Access Identities upon request from upper layers or the RRC layer.

A timer associated with access control may be configured for each of Access Categories. For example, the timer may be T390.

If the access attempt is considered as barred, the UE may start T390 for an Access Category. The UE shall defer access barring checks until the timer expires.

The UE in the RRC_CONNECTED state may stop the timer upon reception of an RRCReconfiguration signaling including reconfigurationWithSync and when handover is successfully completed, or when a sidelink (SL) path switch procedure is successfully completed. Referring to the change history of stopping the timer, it is essentially because a serving cell of the UE is changed.

As described with reference to Fig. 1A, 1B, 1C, 1D, 1E, 1F or 1G, in an MP scenario, one of the following cases may be involved: addition of at least one path for an MP operation, release of at least one of multiple paths, or change of at least one of the multiple paths. Signaling of path switch may be reused or PCell may be changed, but the actual serving cell may not change in the above cases.

For example, in Fig. 1B, addition of the direct path 140 for MP operation may involve a path switch procedure in which a target configuration for MP operation may contain the direct path 140 and the indirect path 150. A PCell is configured for the terminal device 110 (i.e., the remote UE) .

The terminal device 110 may be in the same coverage of the cell via the added direct path 140 and the indirect path 150 when the terminal device 110 is in an RRC_CONNECTED state. In other words, the serving cell 120 on the added direct path 140 and the serving cell 124 on the indirect path 150 may be the same cell. This means there is no serving cell change during the path switch procedure for the addition of the direct path 140.

For another example, in Fig. 1D, when releasing the direct path 140, the procedure may be supported by a simple radio bearer reconfiguration procedure. For example, reconfigurationWithSync may not be needed. The PCell may be implicitly changed.

It is also possible that the direct path 140 and the indirect path 150 are intra-cell MP. In other words, the serving cell 120 on the added direct path 140 and the serving cell 124 on the indirect path 150 may be the same cell. Then, for the implicit PCell change, especially for release of one path (such as a direct path) , there is no serving cell change.

For a further example, in Fig. 1E, change from the indirect path 150 to the indirect path 152 within the same cell may occur. The indirect-to-indirect (i2i) procedure could be enabled with sl-PathSwitchConfig included in reconfigurationWithSync. Neither the serving cell on the direct path 140 nor the serving cell on the indirect path 152 has changed.

In view of the above, it needs to discuss whether to stop a timer associated with access control (if running) if there is no serving cell change when a path for MP operation is updated. It needs to discuss when to stop the timer.

Embodiments of the present disclosure provide a solution for MP communications. In one aspect of the solution, a terminal device determines that at least one condition associated with update of at least one of multiple paths for MP operation is satisfied. The terminal device also determines an occasion associated with the update of the at least one of multiple paths. In turn, the terminal device controls, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control. With the solution, the timer associated with access control may be handled for various cases in an MP scenario.

Hereinafter, principle of the present disclosure will be described with reference to Figs. 2 to 4.

Fig. 2 illustrates a flowchart of a method 200 implemented at a terminal device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 200 will be described from the perspective of the terminal device 110 with reference to Fig. 1A, 1B, 1C, 1D, 1E, 1F or 1G.

At block 210, the terminal device 110 determines that at least one condition associated with update of at least one of multiple paths for MP operation is satisfied.

In some embodiments, the update of the at least one of the multiple paths may comprise one of the following:

- addition of at least one path for the MP operation,

- release of at least one of the multiple paths, or

- change of at least one of the multiple paths.

At block 220, the terminal device 110 determines an occasion associated with the update of the at least one of multiple paths.

In some embodiments, the occasion may comprise one of the following:

- a first time when a procedure associated with the update is successfully completed, or

- a second time when the at least one condition is satisfied.

At block 230, the terminal device 110 controls, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.

With the method 200, the timer associated with access control may be handled for various cases in an MP scenario.

It shall be understood that although the block 220 is illustrated subsequent to the block 210, the action in the block 220 may be performed before or in parallel to the action in the block 210.

Fig. 3 illustrates a flowchart of a method 300 implemented at a network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 300 will be described from the perspective of the network device 120 with reference to Fig. 1A, 1B, 1C, 1D, 1E, 1F or 1G.

At block 310, the network device 120 determines to update at least one of multiple paths for MP operation.

At block 320, the network device 120 transmits a signaling for the update to the terminal device 110.

With the method 300, the timer associated with access control may be handled for various cases in an MP scenario.

In a first solution, the network device 120 may determine how to control the timer associated with access control in MP operation. The network device 120 may transmit, to the terminal device 110, an indication indicating whether to stop the timer. In turn, the terminal device 110 may control the timer based on the indication.

In a second solution, the terminal device 110 may determine how to control the timer associated with access control in MP operation. The timer associated with an Access Category (AC) or traffic is started if the access attempt for the AC or traffic is determined to be barred. In some embodiment, if the terminal device 110 determines that a first serving cell on an updated path for the MP operation is different from at least one second serving cell on at least one existing path, the terminal device 110 may stop the timer. Otherwise, the terminal device 110 may keep the timer running.

Hereinafter, some embodiments for the first and second solutions will be described taking one direct path and one indirect path for example. It shall be noted that multiple direct paths or multiple indirect paths may be applied to the present disclosure.

Addition of a direct path

Embodiment #1-1 for the first solution

For the purpose of discussion, Embodiment #1-1 will be described with reference to Figs. 1B and 1F. In Embodiment #1-1, update of at least one of multiple paths comprises addition of one direct path.

As shown in Fig. 1B, the direct path 140 may be established and added after the indirect path 150 was established. As shown in Fig. 1F, the direct path 142 may be established and added after the direct path 140 as well as the indirect paths 150 and 152 were established.

Upon determining to update at least one of multiple paths for MP operation, the network device 120 transmits a signaling for update of the at least one of multiple paths to the terminal device 110.

In some embodiments, the signaling for the update may comprise a configuration for MP operation. The configuration may indicate at least one direct path and at least one indirect path are to be used for MP operation. For example, in the example of Fig. 1B, the configuration may indicate the direct path 140 and the indirect path 150 are to be used for MP operation. For another example, in the example of Fig. 1F, the configuration may indicate the direct paths 140 and 142 as well as the indirect paths 150 and 152 are to be used for MP operation.

In some embodiments, the signaling for the update may be an RRC signaling to be applied to MP operation. The RRC signaling may be an RRCReconfiguration signaling. For example, reconfigurationWithSync may be included in the RRCReconfiguration signaling, or reconfigurationWithSync may be included in spCellConfig of a Master Cell Group (MCG) in the RRCReconfiguration signaling.

Alternatively, the RRCReconfiguration signaling may comprise a dedicated or new information element (IE) . The dedicated or new IE indicates to add at least one path (direct path or indirect path) . For example, the new IE may be included in the RRCReconfiguration signaling, or the new IE may be included in reconfigurationWithSync in the RRCReconfiguration signaling.

In some embodiments, if the signaling for the update is received from the network device 120, the terminal device 110 may determine that the at least one condition associated with the update is satisfied.

In some embodiments, the network device 120 may transmit, to the terminal device 110, an indication indicating whether to stop the timer.

In some embodiments, the indication indicating whether to stop the timer may be included in the signaling for the update. Alternatively, the indication may be transmitted separately from the signaling for the update.

In some embodiments, if the indication indicating whether to stop the timer is received from the network device 120, the terminal device 110 may further determine that the at least one condition associated with the update is satisfied. In other words, if the signaling for the update and the indication are received from the network device 120, the terminal device 110 may determine that the at least one condition associated with the update is satisfied.

In some embodiments, in order to add the direct path 140 or 142, upon receiving the signaling for the update, the terminal device 110 may perform a procedure associated with the update based on the signaling for the update.

For example, the procedure associated with the update may comprise a path switch procedure to add the direct path 140 or 142. When the path switch procedure is successfully completed, the terminal device 110 may transmit an RRCReconfigurationComplete message to the network device 120. When successfully transmitting the RRCReconfigurationComplete message, the terminal device 110 may confirm the path switch procedure is successfully completed.

For another example, the procedure associated with the update may comprise a Random Access procedure.

In some embodiments, the occasion associated with the update of the at least one of multiple paths may comprise a first time when the procedure associated with the update is successfully completed.

In such embodiments, when the terminal device 110 confirms that the procedure associated with the update is successfully completed, for example, by transmitting the RRCReconfigurationComplete message, or when completing the Random Access procedure, or a specific message to respond to the successful procedure associated with the update is transmitted, the terminal device 110 may control the timer based on the indication received from the network device 120. For example, if the indication indicates to stop the timer when updating the at least one path or when performing the procedure associated with the update, the terminal device 110 may stop the timer (if running) for all access categories.

In some embodiments, the occasion associated with the update of the at least one of multiple paths may comprise a second time when the at least one condition is satisfied. In such embodiments, when the at least one condition is satisfied, the terminal device 110 may control the timer based on the indication received from the network device 120. For example, if the indication indicates to stop the timer when updating the at least one path or when performing the procedure associated with the update, the terminal device 110 may stop the timer (if running) for all access categories.

Addition of a direct path

Embodiment #1-2 for the first solution

For the purpose of discussion, Embodiment #1-2 will be described with reference to Figs. 1B and 1F. In Embodiment #1-2, update of at least one of multiple paths comprises addition of one direct path.

Embodiment #1-2 is similar to Embodiment #1-1. Embodiment #1-2 is different from Embodiment #1-1 in that in Embodiment #1-2, the at least one condition associated with update of at least one of multiple paths is preconfigured, and the terminal device 110 may autonomously determine that the at least one preconfigured condition is satisfied. In addition, in Embodiment #1-2, the at least one preconfigured condition comprises the indication indicating whether to stop the timer.

Upon determining that the at least one preconfigured condition is satisfied, the terminal device 110 may autonomously perform a procedure associated with the update so as to add the direct path 140 or 142.

Similar to Embodiment #1-1, in Embodiment #1-2, when the terminal device 110 confirms that the procedure associated with the update is successfully completed, for example, by transmitting the RRCReconfigurationComplete message, or when completing the Random Access procedure, or a specific message to respond to the successful procedure associated with the update is transmitted, the terminal device 110 may control the timer based on the indication received from the network device 120.

Alternatively, similar to Embodiment #1-1, in Embodiment #1-2, when the at least one preconfigured condition is satisfied, the terminal device 110 may control the timer based on the indication received from the network device 120.

Addition of a direct path

Embodiment #1-3 for the second solution

For the purpose of discussion, Embodiment #1-3 will be described with reference to Figs. 1B and 1F. Similar to Embodiments #1-1 and #1-2, in Embodiment #1-3, update of at least one of multiple paths comprises addition of one direct path. The terminal device 110 may perform a procedure associated with the update based on a signaling for the update received from the network device 120 or based on determining that the at least one preconfigured condition is satisfied.

Embodiment #1-3 is different from Embodiments #1-1 and #1-2 in that in Embodiment #1-3, the network device 120 does not transmit, to the terminal device 110, the indication indicating whether to stop the timer. Instead, the terminal device 110 may determine how to control the timer associated with access control in MP operation.

In some embodiment, the terminal device 110 may determine whether a first serving cell on an updated path for the MP operation is different from at least one second serving cell on at least one existing path. The at least one existing path was comprised in the multiple paths before the update. In other words, the terminal device 110 may determine whether the updated path and the at least one existing path belong to the different cell. If the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

In embodiment where the update comprises addition of a path for the MP operation, the updated path is the added path for the MP operation. For example, if the update comprises addition of the direct path 140 for the MP operation as shown in Fig. 1B, the updated path is the added direct path 140 and the existing path is the indirect path 150. If the first serving cell on the added direct path 140 is different from the second serving cell on the indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for another example, if the update comprises addition of the direct path 142 for the MP operation as shown in Fig. 1F, the updated path is the added direct path 142 and the existing path may be the direct path 140. If the first serving cell on the added direct path 142 is different from the second serving cell on the direct path 140, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for a further example, if the update comprises addition of the direct path 142 for the MP operation as shown in Fig. 1F, the updated path is the added direct path 142 and the existing path may be the indirect path 150. If the first serving cell on the added direct path 142 is different from the second serving cell on the indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for a still further example, if the update comprises addition of the direct path 142 for the MP operation as shown in Fig. 1F, the updated path is the added direct path 142 and the existing path may be the indirect path 152. If the first serving cell on the added direct path 142 is different from the second serving cell on the indirect path 152, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

In some embodiments, at least one existing path may comprise one or more existing paths. For example, in the example of Fig. 1B, the at least one existing path may comprise the indirect path 150. For another example, in the example of Fig. 1F, the at least one existing path may comprise the direct path 140 as well as the indirect paths 150 and 152.

In some embodiment, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on identifiers (IDs) of the first serving cell and the at least one second serving cell.

Alternatively, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on an indication received from the network device 120. For example, the network device 120 may explicitly indicate the first serving cell on the updated path is the same as or different from the at least one second serving cell on the at least one existing path.

The occasion when the terminal device 110 stops the timer in Embodiment #1-3 may be the same as those described in Embodiments #1-1 and #1-2. The details of the occasion are omitted for brevity.

It shall be noted that although the addition of one direct path have been described by way of example, additions of two or more direct paths or addition of one or more indirect paths may be applied to the present disclosure.

Release of a direct path

Embodiment #2-1 for the second solution

For the purpose of discussion, Embodiment #2-1 will be described with reference to Figs. 1D or 1G. As shown in Fig. 1D, the direct path 140 may be released. As shown in Fig. 1G, the direct paths 140 and 142 as well as the indirect path 152 may be released while the indirect path 150 may be maintained.

Upon determining to update at least one of multiple paths for MP operation, the network device 120 transmits a signaling for update of the at least one of multiple paths to the terminal device 110. In Embodiment #2-1, the update of at least one of multiple paths comprises release of one or more direct paths.

In some embodiments, the signaling for the update may comprise a configuration for MP operation. The configuration may indicate to release the direct path 140 as shown in Fig. 1D. Alternatively, the configuration may indicate to release all paths except the indirect path 150 as shown in Fig. 1G.

The signaling for the update may be an RRC signaling to be applied to MP operation. The RRC signaling may be an RRCReconfiguration signaling. For example, reconfigurationWithSync may be included in the RRCReconfiguration signaling, or reconfigurationWithSync may be included in spCellConfig of an MCG in the RRCReconfiguration signaling.

Alternatively, the RRCReconfiguration signaling may comprise a dedicated or new IE.The dedicated or new IE indicates to release at least one path (direct path or indirect path) . For example, the new IE may be included in the RRCReconfiguration signaling, or the new IE may be included in reconfigurationWithSync in the RRCReconfiguration signaling.

Alternatively, the at least one condition associated with the update of at least one of multiple paths is preconfigured, and the terminal device 110 may autonomously determine that the at least one preconfigured condition is satisfied.

In addition, similar to Embodiment #1-3, in Embodiment #2-1, the terminal device 110 may determine whether a first serving cell on an updated path for the MP operation is different from at least one second serving cell on at least one existing path. The at least one existing path was comprised in the multiple paths before the update. In other words, the terminal device 110 may determine whether the updated path and the at least one existing path belong to the different cell. If the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

In embodiment where the update comprises release of a path for the MP operation, the updated path is the released path for the MP operation and the at least one existing path is at least one maintained path for the MP operation.

For example, as shown in Fig. 1D, if the update comprises release of the direct path 140 for the MP operation, the updated path is the released direct path 140 and the existing path is the maintained indirect path 150. If the first serving cell on the released direct path 140 is different from the second serving cell on the maintained indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for another example, as shown in Fig. 1G, if the update comprises release of the direct paths 140 and 142 as well as the indirect path 152, the updated path may be the released direct path 140 and the existing path is the maintained indirect path 150. If the first serving cell on the released direct path 140 is different from the second serving cell on the maintained indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for a further example, as shown in Fig. 1G, if the update comprises release of the direct paths 140 and 142 as well as the indirect path 152, the updated path may be the released direct path 142 and the existing path is the maintained indirect path 150. If the first serving cell on the released direct path 142 is different from the second serving cell on the maintained indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, for a still further example, as shown in Fig. 1G, if the update comprises release of the direct paths 140 and 142 as well as the indirect path 152, the updated path may be the released indirect path 152 and the existing path is the maintained indirect path 150. If the first serving cell on the released indirect path 152 is different from the second serving cell on the maintained indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Similar to Embodiment #1-3, in Embodiment #2-1, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on IDs of the first serving cell and the at least one second serving cell. Alternatively, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on an indication received from the network device 120.

Alternatively, in Embodiment #2-1, each of the first serving cell and the at least one second serving cell may comprise a primary cell (PCell) . The terminal device 110 may determine whether a first PCell on an updated path for the MP operation is different from at least one second PCell on at least one existing path. The at least one existing path was comprised in the multiple paths before the update. In other words, the terminal device 110 may determine whether the updated path and the at least one existing path belong to the different serving cell. If the ID (e.g. physical cell identity) of the first PCell on the updated path is different from the ID (e.g. physical cell identity) of the at least one second PCell on the at least one existing path, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

The occasion when the terminal device 110 stops the timer in Embodiment #2-1 may be the same as those described in Embodiments #1-1 and #1-2. The details of the occasion are omitted for brevity.

Change of an indirect path

Embodiment #3-1 for the second solution

For the purpose of discussion, Embodiment #3-1 will be described with reference to Fig. 1E. As shown in Fig. 1E, if the indirect path 150 is released, in order to maintain the MP operation, the indirect path 152 may be established and added for the MP operation. In other words, an indirect path for the MP operation may change from the indirect path 150 to the indirect path 152.

Upon determining to update at least one of multiple paths for MP operation, the network device 120 transmits a signaling for update of the at least one of multiple paths to the terminal device 110. In Embodiment #3-1, the update of at least one of multiple paths comprises change of one indirect path.

In some embodiments, the signaling for the update may comprise a configuration for MP operation. The configuration may indicate to change an indirect path for the MP operation from the indirect path 150 to the indirect path 152 as shown in Fig. 1E. Alternatively, the configuration may indicate the latest multiple paths for the MP operation. For example, the configuration may indicate the direct path 140 and the indirect path 152 are to be used for the MP operation.

Alternatively, the RRCReconfiguration signaling may comprise a dedicated or new IE.The dedicated or new IE indicates to change at least one path (direct path or indirect path) or indicates the latest multiple paths for the MP operation. For example, the new IE may be included in the RRCReconfiguration signaling, or the new IE may be included in reconfigurationWithSync in the RRCReconfiguration signaling.

In addition, similar to Embodiment #1-3, in Embodiment #3-1, the terminal device 110 may determine whether a first serving cell on an updated path for the MP operation is different from at least one second serving cell on at least one existing path. The at least one existing path was comprised in the multiple paths before the update. In other words, the terminal device 110 may determine whether the updated path and the at least one existing path belong to the different cell. If the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

In embodiment where the update comprises change of a path for the MP operation, the updated path is the changed path for the MP operation. For example, as shown in Fig. 1E, if the update comprises change of an indirect path from the indirect path 150 to the indirect path 152, the updated path may be the changed indirect path 152 and the at least one existing path may be the indirect path 150. If the first serving cell on the changed indirect path 152 is different from the second serving cell on the indirect path 150, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Alternatively, if the update comprises change of an indirect path from the indirect path 150 to the indirect path 152, the updated path may be the changed indirect path 152 and the at least one existing path may be the direct path 140. If the first serving cell on the changed indirect path 152 is different from the second serving cell on the direct path 140, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

Similar to Embodiment #1-3, in Embodiment #3-1, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on IDs of the first serving cell and the at least one second serving cell. Alternatively, the terminal device 110 may determine whether the first serving cell on the updated path is different from the at least one second serving cell on the at least one existing path based on an indication received from the network device 120.

Alternatively, in Embodiment #3-1, each of the first serving cell and the at least one second serving cell may comprise a PCell. The terminal device 110 may determine whether a first PCell on an updated path for the MP operation is different from at least one second PCell on at least one existing path. The at least one existing path was comprised in the multiple paths before the update. In other words, the terminal device 110 may determine whether the updated path and the at least one existing path belong to the different PCell. That is, the terminal device 110 may determine whether change of a path results in PCell change.

If the first PCell on the updated path is different from the at least one second PCell on the at least one existing path, the terminal device 110 may stop the timer for all access categories. Otherwise, the terminal device 110 may keep the timer running.

The occasion when the terminal device 110 stops the timer in Embodiment #3-1 may be the same as those described in Embodiments #1-1 and #1-2. The details of the occasion are omitted for brevity.

Addition, release or change of at least one path

Embodiment #4-1 for the second solution

In Embodiment #4-1, upon determining to update at least one of multiple paths for MP operation, the network device 120 transmits a signaling for update of the at least one of multiple paths to the terminal device 110.

In some embodiments, the signaling for the update may comprise a configuration for MP operation. The configuration may indicate addition, release or change of at least one path for MP operation.

If the signaling for the update is received from the network device 120, the terminal device 110 may determine that the at least one condition associated with the update is satisfied.

In turn, the terminal device 110 may stop the timer for all access categories.

Alternatively, the terminal device 110 may stop the timer for all access categories if a path switch procedure is used or reconfigurationWithSync is included in the the signaling for the update. For example, if sl-PathSwitchConfig was included in reconfigurationWithSync included in spCellConfig of an MCG, or reconfigurationWithSync was included in spCellConfig of an MCG, or reconfigurationWithSync was included in spCellConfig, or sl-PathSwitchConfig was included in reconfigurationWithSync, the terminal device 110 may stop the timer for all access categories.

The occasion when the terminal device 110 stops the timer in Embodiment #4-1 may be the same as those described in Embodiments #1-1 and #1-2. The details of the occasion are omitted for brevity.

Addition, release or change of at least one path

Embodiment #4-2 for the second solution

In Embodiment #4-2, upon determining to update at least one of multiple paths for MP operation, the network device 120 transmits a signaling for update of the at least one of multiple paths to the terminal device 110.

In turn, the terminal device 110 may keep the timer running.

Alternatively, if the configuration for MP operation indicates addition of at least one path for MP operation, the terminal device 110 may keep the timer running.

The occasion when the terminal device 110 stops the timer in Embodiment #4-2 may be the same as those described in Embodiments #1-1 and #1-2. The details of the occasion are omitted for brevity.

Fig. 4 illustrates a simplified block diagram of an apparatus 400 that is suitable for implementing embodiments of the present disclosure. The apparatus 400 can be considered as a further example implementation of the terminal device 110 or the network device 120 as shown in Figs. 1A to 1G. Accordingly, the apparatus 400 can be implemented at or as at least a part of the terminal device 110 or the network device 120.

As shown, the apparatus 400 includes a processor 410, a memory 420 coupled to the processor 410, a suitable transmitter (TX) and receiver (RX) 440 coupled to the processor 410, and a communication interface coupled to the TX/RX 440. The memory 410 stores at least a part of a program 430. The TX/RX 440 is for bidirectional communications. The TX/RX 440 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this disclosure may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 430 is assumed to include program instructions that, when executed by the associated processor 410, enable the apparatus 400 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Figs. 1A to 1G, 2 and 3. The embodiments herein may be implemented by computer software executable by the processor 410 of the apparatus 400, or by hardware, or by a combination of software and hardware. The processor 410 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 410 and memory 420 may form processing means 450 adapted to implement various embodiments of the present disclosure.

The memory 420 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 420 is shown in the apparatus 400, there may be several physically distinct memory modules in the apparatus 400. The processor 410 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The apparatus 400 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A terminal device, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

determine that at least one condition associated with update of at least one of multiple paths for multi-path operation is satisfied;

determine an occasion associated with the update of the at least one of multiple paths; and

control, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.
The terminal device of claim 1, wherein the update of the at least one of the multiple paths comprises one of the following:

addition of at least one path for the multi-path operation,

release of at least one of the multiple paths, or

change of at least one of the multiple paths.
The terminal device of claim 1, wherein the processor is caused to determine that the at least one condition is satisfied by:

determining that a signaling for the update is received via the transceiver from a network device.
The terminal device of claim 3, wherein the processor is caused to determine that the at least one condition is satisfied further by:

determining that an indication indicating whether to stop the timer is received via the transceiver from the network device.
The terminal device of claim 4, wherein the signaling comprises the indication.
The terminal device of claim 1, wherein the at least one condition is preconfigured, and the processor is caused to determine that the at least one condition is satisfied by:

autonomously determining that the at least one condition is satisfied.
The terminal device of claim 6, wherein the at least one condition comprises an indication indicating whether to stop the timer.
The terminal device of claim 1, wherein the processor is caused to determine that the at least one condition is satisfied by:

determining that a first serving cell on an updated path for the multi-path operation is different from at least one second serving cell on at least one existing path, wherein the at least one existing path was comprised in the multiple paths before the update.
The terminal device of claim 1, wherein the occasion comprises one of the following:

a first time when a procedure associated with the update is successfully completed, or

a second time when the at least one condition is satisfied.
The terminal device of claim 1, wherein the processor is caused to control the timer by one of the following:

stopping the timer, or

keeping the timer running.
A network device, comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

determine to update at least one of multiple paths for multi-path operation; and

transmit, via the transceiver to a terminal device, a signaling for update of the at least one of multiple paths.
The network device of claim 11, wherein the signaling comprises an indication indicating whether to stop a timer associated with access control.
A method for communications, comprising:

determining, at a terminal device, that at least one condition associated with update of at least one of multiple paths for multi-path operation is satisfied;

determining an occasion associated with the update of the at least one of multiple paths; and

controlling, based on determining that the at least one condition is satisfied and on the occasion, a timer associated with access control.
A method for communications, comprising:

determining, at a network device, to update at least one of multiple paths for multi-path operation; and

transmitting, to a terminal device, a signaling for update of the at least one of multiple paths.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor of a device, causing the device to carry out the method according to any of claims 13 and 14.