阅读说明：本技术 释放小区组的信令无线电承载 (Releasing signaling radio bearers for a cell group ) 是由 马子江 王昕� 刘静 于 2018-01-10 设计创作，主要内容包括：描述了与双连接(DC)或多连接(MC)场景中信令无线电承载(SRB)的较低层资源的管理有关的方法、系统和设备。在一个示例性方面,一种用于无线通信的方法包括操作无线网络中的第一无线通信节点。该无线网络包括主小区组和至少一个辅小区组,并且该主小区组配置有一个或多个分离信令无线电承载。该方法还包括从无线网络中的第一无线通信节点向无线网络中的第二无线通信节点发送指示主小区组的一个或多个分离信令无线电承载的释放或辅小区组的释放的消息。(Methods, systems, and devices are described relating to management of lower layer resources of a Signaling Radio Bearer (SRB) in a Dual Connectivity (DC) or Multi Connectivity (MC) scenario. In one exemplary aspect, a method for wireless communication includes operating a first wireless communication node in a wireless network. The wireless network includes a master cell group and at least one secondary cell group, and the master cell group is configured with one or more separate signaling radio bearers. The method also includes sending, from a first wireless communication node in the wireless network to a second wireless communication node in the wireless network, a message indicating a release of one or more split signaling radio bearers of the master cell group or a release of the secondary cell group.)

1. A method for wireless communication, comprising:

operating a first wireless communication node in a wireless network, wherein the wireless network comprises a master cell group and at least one secondary cell group, and wherein the first wireless communication node is configured with one or more separate signaling radio bearers; and

sending, from the first wireless communication node, a message to a second wireless communication node in the wireless network, the message indicating a release of the one or more separate signaling radio bearers or a release of the secondary cell group.

2. The method of claim 1, wherein the one or more separate signaling radio bearers are configured for the master cell group.

3. The method of claim 2, wherein the release of the one or more split signaling radio bearers of the master cell group comprises a release of lower layer resources corresponding to the one or more split signaling radio bearers of the master cell group.

4. The method of any of claims 1-3, wherein the message further indicates a release of the one or more signaling radio bearers of the secondary cell group.

5. The method of any of claims 2 to 4, comprising:

receiving, at the first wireless communication node, an acknowledgement from the second wireless communication node, the acknowledgement configured to acknowledge release of the one or more split signaling radio bearers of the primary cell group or release of the secondary cell group.

6. The method of any of claims 2 to 5, wherein the message causes the second wireless communication node to release at least one of:

(1) the one or more separate signaling radio bearers of the master cell group,

(2) lower layer resources corresponding to one or more signaling radio bearers of the secondary cell group, or

(3) Lower layer resources corresponding to the secondary cell group.

7. The method of claim 6, wherein the first wireless communication node is a primary node of the wireless network and the second wireless communication node is a secondary node of the wireless network.

8. The method of any of claims 2 to 5, comprising:

releasing, by the first wireless communication node, at least one of:

(1) the one or more separate signaling radio bearers of the master cell group,

(2) lower layer resources corresponding to one or more signaling radio bearers of the secondary cell group, or

(3) Lower layer resources corresponding to the secondary cell group.

9. The method of claim 8, wherein the first wireless communication node is a secondary node of the wireless network and the second wireless communication node is a primary node of the wireless network.

10. The method of claim 1, wherein the message is a radio resource control message.

11. A method for wireless communication, comprising:

operating a wireless communication node in a wireless network, wherein the wireless network comprises a master cell group and at least one secondary cell group; and

sending a message from the wireless communication node to a mobile device indicating a release of the secondary cell group or a release of one or more signaling radio bearers for the secondary cell group.

12. The method of claim 11, wherein the wireless communication node is a primary communication node in the wireless network and the message indicates a release of the secondary cell group.

13. The method of claim 11, wherein the wireless communication node is a secondary communication node in the wireless network, and the message indicates a release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

14. The method of claim 11, comprising:

receiving, at the wireless communication node, an acknowledgement from the mobile device configured to acknowledge release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

15. A method for wireless communication, comprising:

receiving a message from a communication node in a wireless network, the message indicating a release of a group of cells in the wireless network;

releasing lower layer resources of the cell group; and

avoiding monitoring for one or more failures of the group of cells.

16. The method of claim 15, wherein the cell group is a secondary cell group in the wireless network.

17. The method of claim 15, wherein the lower layer resources comprise lower layer resources corresponding to all data radio bearers and all signaling radio bearers of the group of cells.

18. An apparatus for wireless communication, comprising a processor configured to perform the method of any of claims 1-17.

19. A non-transitory computer-readable medium having code stored thereon, which, when executed by a processor, causes the processor to implement the method of any one of claims 1-17.

Technical Field

This patent document relates generally to digital wireless communications.

Background

Mobile communication technology is moving the world towards increasingly connected and networked society. The rapid growth of mobile communications and advances in technology have resulted in greater demands for capacity and connectivity. Other aspects such as energy consumption, equipment cost, spectral efficiency and latency are also important to meet the needs of various communication scenarios. Various techniques, including new ways of providing higher quality of service, are being discussed.

Summary of the specific embodiments

This document discloses methods, systems, and devices related to digital wireless communications, and more particularly, to techniques related to management of lower layer resources for Signaling Radio Bearers (SRBs) in Dual Connectivity (DC) or Multi Connectivity (MC) scenarios.

In one exemplary aspect, a method for wireless communication is disclosed. The method comprises the following steps: operating a first wireless communication node in a wireless network, wherein the wireless network comprises a master cell group and at least one secondary cell group, and wherein the first wireless communication node is configured with one or more split (split) signaling radio bearers; and sending a message from the first wireless communication node to a second wireless communication node in the wireless network, the message indicating a release of the one or more separate signaling radio bearers or a release of the secondary cell group. The message may be a radio resource control message.

In some embodiments, the one or more separate signaling radio bearers are configured for the master cell group. In some embodiments, the release of the one or more split signaling radio bearers for the master cell group comprises a release of lower layer resources corresponding to the one or more split signaling radio bearers. In some embodiments, the message further indicates a release of the one or more signaling radio bearers for the secondary cell group.

In some embodiments, the method comprises: receiving, at the first wireless communication node, an acknowledgement from the second wireless communication node, the acknowledgement configured to acknowledge release of the one or more split signaling radio bearers of the primary cell group or release of the secondary cell group.

In some embodiments, the message causes the second wireless communication node to release at least one of: (1) the one or more split signaling radio bearers of the master cell group, (2) lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group, or (3) lower layer resources corresponding to the secondary cell group. In some embodiments, the first wireless communication node is a primary node of the wireless network and the second wireless communication node is a secondary node of the wireless network.

In some embodiments, the method comprises: releasing, by the first wireless communication node, at least one of: (1) the one or more split signaling radio bearers of the master cell group, (2) lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group, or (3) lower layer resources corresponding to the secondary cell group. In some embodiments, the first wireless communication node is a secondary node of the wireless network and the second wireless communication node is a primary node of the wireless network.

In another exemplary aspect, a method for wireless communication is disclosed. The method comprises the following steps: operating a wireless communication node in a wireless network, wherein the wireless network comprises a master cell group and at least one secondary cell group; and sending a message from the wireless communication node to a mobile device, the message indicating a release of the secondary cell group or a release of one or more signaling radio bearers of the secondary cell group.

In some embodiments, the wireless communication node is a master communication node in the wireless network and the message indicates a release of the secondary cell group. In some embodiments, the wireless communication node is a secondary communication node in the wireless network, and the message indicates a release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

In some embodiments, the method further comprises: receiving, at the wireless communication node, an acknowledgement from the mobile device configured to acknowledge release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

In another exemplary aspect, a method for wireless communication is disclosed. The method comprises the following steps: receiving a message from a communication node in a wireless network, the message indicating a release of a group of cells in the wireless network; releasing lower layer resources of the cell group; and avoiding monitoring the group of cells for one or more failures.

In some embodiments, the cell group is a secondary cell group in the wireless network. In some embodiments, the lower layer resources include lower layer resources corresponding to all data radio bearers and all signaling radio bearers of the set of cells.

In another exemplary aspect, a wireless communications apparatus is disclosed that includes a transmitter. The transmitter is configured to transmit a message from a first wireless communication node to a second wireless communication node in the wireless network, the message indicating a release of one or more split signaling radio bearers of a master cell group or a release of a secondary cell group. The message may be a radio resource control message. The wireless communications apparatus can also include processor electronics configured to implement the methods described in this document.

In some embodiments, the release of the one or more split signaling radio bearers for the master cell group comprises a release of lower layer resources corresponding to the one or more split signaling radio bearers. In some embodiments, the message further indicates a release of the one or more signaling radio bearers for the secondary cell group.

In some embodiments, the apparatus comprises a receiver configured to receive, at the first wireless communication node, an acknowledgement from the second wireless communication node, the acknowledgement configured to acknowledge release of the one or more split signaling radio bearers of the master cell group or release of the secondary cell group.

In some embodiments, the message causes the second wireless communication node to release at least one of: (1) the one or more split signaling radio bearers of the master cell group, (2) lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group, or (3) lower layer resources corresponding to the secondary cell group. In some embodiments, the first wireless communication node is a primary node of the wireless network and the second wireless communication node is a secondary node of the wireless network.

In some embodiments, the apparatus comprises a processor configured to release, by the first wireless communication node, at least one of: (1) the one or more split signaling radio bearers of the master cell group, (2) lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group, or (3) lower layer resources corresponding to the secondary cell group. In some embodiments, the first wireless communication node is a secondary node of the wireless network and the second wireless communication node is a primary node of the wireless network.

In another exemplary aspect, a wireless communications apparatus is disclosed that includes a transmitter. The transmitter is configured to send a message from the wireless communication node to a mobile device indicating a release of the secondary cell group or a release of one or more signaling radio bearers of the secondary cell group.

In some embodiments, the wireless communication node is a master communication node in the wireless network and the message indicates a release of the secondary cell group. In some embodiments, the wireless communication node is a secondary communication node in the wireless network, and the message indicates a release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

In some embodiments, the apparatus comprises a receiver configured to receive an acknowledgement from the mobile device at the wireless communication node, the acknowledgement configured to acknowledge release of lower layer resources corresponding to the one or more signaling radio bearers of the secondary cell group.

In another exemplary aspect, a wireless communications apparatus is disclosed. The apparatus includes a receiver configured to receive a message from a communication node in a wireless network, the message indicating a release of a group of cells in the wireless network. The apparatus also includes a processor configured to release lower layer resources of the group of cells and avoid monitoring the group of cells for one or more failures.

In some embodiments, the cell group is a secondary cell group in the wireless network. In some embodiments, the lower layer resources include lower layer resources corresponding to all data radio bearers and all signaling radio bearers of the set of cells.

In yet another exemplary aspect, the various techniques described herein may be embodied as processor-executable code and stored on a computer-readable program medium.

The details of one or more implementations are set forth in the accompanying drawings, and the description below. Other features will be apparent from the description and drawings, and from the claims.

Brief description of the drawings

Fig. 1 shows an exemplary schematic diagram of a system architecture for Dual Connectivity (DC).

Fig. 2 shows a schematic diagram of a layer 2(L2) radio protocol stack of a Master Cell Group (MCG) Radio Bearer (RB).

Fig. 3A shows a schematic diagram of the L2 radio protocol stack with MCG splitting RBs on two network elements.

Fig. 3B shows an example of an L2 radio protocol stack for a Secondary Cell Group (SCG) Radio Bearer (RB).

Fig. 4A illustrates an example of decoupling a higher layer entity from a lower layer entity in a Dual Connectivity (DC) or Multi Connectivity (MC) mode.

Fig. 4B illustrates another example of decoupling a higher layer entity from a lower layer entity in a Dual Connectivity (DC) or Multi Connectivity (MC) mode.

Fig. 5 is a flowchart representation of a method for wireless communication.

Fig. 6 is a flow chart representation of another method for wireless communication.

Fig. 7 is a flow chart representation of another method for wireless communication.

Fig. 8 illustrates an example of a wireless communication system in which techniques in accordance with one or more embodiments of the present technology may be applied.

Fig. 9 is a block diagram representation of a portion of a radio station.

Detailed Description

With the continuous development of wireless communication technology, a wide range of wireless communication services are emerging, which will greatly increase the bandwidth requirements in wireless communication systems. The development of a new generation of wireless communications-5G New Radio (NR) communications-is part of the ongoing mobile broadband evolution process to meet the demands of ever-increasing network demands. NR will provide greater throughput to allow more users to connect simultaneously. Aspects such as energy consumption, equipment cost, spectral efficiency and latency are important to meet the needs of various communication scenarios.

With the advent of NR in the wireless technology area, User Equipment (UE) will be able to support both existing protocols (e.g., Long Term Evolution (LTE)) and NR protocols. Fig. 1 shows an exemplary schematic diagram of a system architecture for Dual Connectivity (DC). Some example embodiments of a DC may include a system configuration or operating mode of a wireless device in which a user device may operate with two logically separate communication connections to a network. A current base station (referred to as a first network element 101) currently serving the UE and coupled to the core network 103 may select a suitable further base station for the UE 100 to use as the second network element 102. For example, a suitable base station may be selected by selecting a candidate base station and comparing the channel quality of the candidate base station (the channel between the candidate base station and the UE) to a predetermined threshold. Once selected, both base stations may provide radio resources to the UE 100 for data transmission on the user plane.

On the wired interface side (e.g., backhaul connection), the first network element 101 and the core network 103 establish one or more interfaces 104 (e.g., control plane interface and user plane interface) for the UE 100. The second network element 102 and the core network 103 may establish one or more interfaces 105 (e.g., control plane interfaces and/or user plane interfaces) for the UE 100. An interface 106 (e.g., an Xn interface) interconnects two network elements.

On the radio interface side, the first and second network elements (101 and 102) may provide radio resources using the same or different Radio Access Technologies (RATs). Each network element may independently schedule transmissions with the UE 100. One network element (e.g., first network element 101) serves as a primary node (MN) and the other network element (e.g., second network element 102) serves as a Secondary Node (SN). In some cases, the UE 100 may be connected to more than two nodes, with one node acting as a MN and the remaining nodes acting as SNs.

In some embodiments, the UE may support LTE-NR dual connectivity. For example, one of the typical LTE-NR dual connectivity architectures may be established as follows: the MN is an LTE RAN node (e.g., eNB) and the SN is an NR RAN node (e.g., gNB). The eNB and the gNB are connected to an Evolved Packet Core (EPC) network (e.g., LTE core network). The architecture shown in fig. 1 may also be modified to include various master/slave node configurations. For example, the NR RAN node may be a MN and the LTE RAN node may be a SN. In this case, the core network for the main NR RAN node is a next generation aggregation network (NG-CN), which may also be referred to as a 5G core network (5 GC). In each dual connectivity scenario, one network (e.g., an LTE network) is responsible for solving the coverage problem, while the other network (e.g., an NR network) is responsible for improving throughput. The architecture shown in fig. 1 can also be extended to support Multiple Connectivity (MC) where one MN and multiple SNs provide both coverage and throughput for UE access.

In wireless communications, a Radio Bearer (RB) is a virtual concept that defines how data and/or signaling from a UE is handled as it travels over a network. There are two categories of RBs: a Data Radio Bearer (DRB) for carrying User Plane (UP) traffic (traffic) and a Signaling Radio Bearer (SRB) for carrying Control Plane (CP) traffic. Fig. 2 shows a schematic diagram of a layer 2(L2) radio protocol stack of a Master Cell Group (MCG) RB. The protocol stack 200 includes a Packet Data Convergence Protocol (PDCP) entity 202, a Radio Link Control (RLC) entity 204, and a Medium Access Control (MAC) entity 206. For SRBs carrying CP traffic, a Radio Resource Control (RRC) entity is located above the L2 protocol stack.

If the network element is responsible for data transmission with the UE, the network element establishes a serving cell and at least one DRB to carry data traffic with the UE. For example, if a secondary node (e.g., a gNB) performs data transmission with a UE, it may establish a primary cell of a secondary cell group (PScell) and at least one Secondary Cell Group (SCG) DRB. Further, the secondary node (e.g., the gNB) may establish one or more Signaling Radio Bearers (SRBs) to carry the typically small amount of control traffic with the UE.

In DC or MC scenarios, Signaling Radio Bearers (SRBs) may be classified into the following categories: master Cell Group (MCG) split SRB1 (also known as SRB1S), Master Cell Group (MCG) split SRB2 (also known as SRB2S), and Secondary Cell Group (SCG) SRB (also known as SRB 3). Fig. 3A-3B illustrate examples of different types of SRBs. For example, as shown in fig. 3A, the L2 protocol stack of the MCG split SRB (SRB1S or SRB2S) is disposed on two serving network elements. The MCG separation SRB is configured with two sets of RLC entities and MAC entities. The CP interface is on a first network element (e.g., MN) and the PDCP entity is located on the same network element. Fig. 3B shows an example of an SCG SRB (i.e., SRB3) configured on a single network element (i.e., SN). The L2 radio protocol stack of SRB3 is similar to the MCG RB shown in fig. 2. Note that although the description in this patent document focuses on MCG split RBs, similar types of split radio bearers can also be configured for SCG such that each SCG split RB has two sets of lower layer resources (e.g., RLC and MAC entities) disposed on two serving network elements (i.e., MN and SN) and a set of higher layer resources (e.g., PDCP entities) disposed on one network element (i.e., SN).

The above SRB types are designed as bearer type coordination. That is, the UE does not distinguish between one or more network elements corresponding to the PDCP entity. For example, in some embodiments, the bearer types may all be configured as NR PDCP entities. Such a design also allows higher layer entities (e.g., PDCP entities) to be decoupled from lower layer entities (e.g., RLC and MAC entities). Fig. 4A-4B illustrate examples of decoupling a higher layer entity from a lower layer entity in DC or MC mode. Fig. 4A shows an example of an inter-MCG NB bearer. In this example, the CP interface and higher layer entities are located at a first network element (i.e., MN). The lower layer entities are decoupled and located at the second network element (i.e., SN). Fig. 4B shows an example of inter-SCG NB bearers. In this example, the CP interface and higher layer entities are located at a second network element (i.e., SN). The lower layer entities are decoupled and located at the first network element (i.e., MN).

With the development of communication standards, a new DRB bearer type-SN terminated (terminated) CG bearer was introduced to allow decoupling of lower and higher layer resources for data traffic. For example, the PDCP entity for the SN terminated MCG bearer is configured on the SN, while the RLC and MAC entities are configured only on the MN. One advantage of using the new DRB type is that the network side no longer needs to configure RLC or MAC entities for the UE on the SN, and the UE does not need to monitor signal quality such as SN Radio Link Failure (RLF) or detect SN failures on the SN side. This is still particularly useful when the coverage of the SN is low for data traffic, but it is still desirable for the UE to perform control transmissions with the SN.

However, if an SRB is established between the UE and the SN, the new DRB type-SN terminates the MCB bearer-will not completely prevent the UE from monitoring signal quality or failure on the SN. Currently, once an SRB is established, the SRB is not released until after the SN is removed or the UE changes to another SN. Therefore, the RLC entity for SRB persists, causing the UE to continuously monitor SN signal quality and SN failure, even when it is not necessary to do so.

This patent document describes a method and corresponding apparatus that allows for the release of lower layer resources of one or more SRBs and, if necessary, allows a UE to skip SN-failure SRB fault detection and/or SN signal quality monitoring, thereby reducing the bandwidth and power consumption of the UE. Details of the technique are described in the following examples. In each of the following embodiments, the network may establish one or more MCG split SRBs (e.g., SRB1S and/or SRB2S) using the following steps:

step A.1: the MN first sends a message (e.g., "SN ADDITION REQUEST") to the SN. The message includes an information element such as "requested MCG detach SRB" to establish one or more MCG detach SRBs.

Step A.2: upon receiving the REQUEST message, the SN sends a response (e.g., "SN ADDITION REQUEST acknowledgement") to the MN. The message includes an information element such as "allowed MCG detach SRB" to notify the MN of the established MCG detach SRB. The MN and SN may make a release of lower layer resources corresponding to the SRB, as appropriate.

Example embodiment 1

This embodiment describes an exemplary signaling procedure between the MN and the SN regarding the management of SRBs. Fig. 5 is a flow chart representation of a method 500 for wireless communication. The method 500 includes operating a first wireless communication node in a wireless network, at 502. The wireless network includes a master cell group and at least one secondary cell group. The first wireless communication node is configured with one or more separate signaling radio bearers. The method 500 further includes sending, from the first wireless communication node in the wireless network to a second wireless communication node in the wireless network, a message indicating a release of the one or more split signaling radio bearers or a release of the secondary cell group, at 504.

Separate signaling radio bearers for the master cell group (e.g., SRB1S and/or SRB2S) have lower layer resources in both the master cell group and the secondary cell group (also referred to as the MCG leg and the SCG leg). In some embodiments, the message indicates a release of one or more separate signaling radio bearers for the master cell group. In some embodiments, the message indicates a release of lower layer resources corresponding to one or more split signaling radio bearers of the master cell group. After the release of the lower layer resources of the secondary cell group, the split signaling radio bearer may be considered released or changed to a signaling radio bearer of the master cell group configured with only the lower layer resources of the master cell group. Thus, in this case, the message also indicates the release of the separate signalling radio bearer for the master cell group.

Either the MN or the SN may initiate the release procedure. Both of these cases will be described in further detail below.

MN initiates SRB Release procedure

When the MN initiates the SRB release procedure, the MN may perform the following steps:

step B.1: the MN sends a message (e.g., "SN MODIFICATION REQUEST") to the SN. The message may include an information element such as "requested release MCG split SRB" to request release of lower layer resources corresponding to MCG split SRBs (e.g., SRB1S and/or SRB2S) on the SN. In some embodiments, the message may include an information element such as "requested SCG release" to request the release of SCG.

Step B.2: upon receipt of the message, the SN sends a response message (e.g., "SN MODIFICATION REQUEST acknowledgement") to the MN. The message may include an information element such as "allowed release MCG split SRB" to confirm the release of lower layer resources corresponding to MCG split SRB on the SN. In some embodiments, the message may include an information element such as "allowed SCG release" to confirm the release of SCG.

SN initiated SRB Release procedure

When the SN initiates the SRB release procedure, the SN may perform the following steps:

step C.1: the SN sends a message (e.g., "SN MODIFICATION request") to the MN. The message may include an information element such as "requested release MCG split SRB" to request release of lower layer resources corresponding to split SRBs (e.g., SRB1S and/or SRB2S) on the SN. In some embodiments, the message may include an information element such as "requested SCG release" to request the release of SCG.

Step C.2: after receiving the message, the MN sends a response message (e.g., "SN MODIFICATION CONFIRM") to the SN. The message includes an information element such as "allowed release MCG split SRB" to confirm the release of lower layer resources corresponding to MCG split SRB on the SN. In some embodiments, the message may include an information element such as "allowed SCG release" to confirm the release of SCG.

Special cases of SRB3

Currently, SRB3 is configured only on the SN side; the MN is agnostic to its presence. Thus, the SN needs to initiate the establishment and release of SRB3 itself.

There is no bearer between the SN and the UE before the establishment of SRB 3. Thus, the SN needs to pass information to the MN so that the MN can relay the information to the UE to establish SRBs 3.

To establish SRB3, the SN may perform the following steps:

step D.1: the SN determines that it needs to establish one or more SRBs 3.

Step D.2: the SN configures lower layer resources corresponding to the one or more SRBs 3, such as corresponding one or more SCG RLC bearers.

Step D.3: the SN passes the information of one or more SRBs 3 to the MN so that the MN can relay the information to the UE.

The MN will then relay the relevant SRB3 information via a message (e.g., an RRC reconfiguration message) to establish SRBs 3 between the SN and the UE. After establishment of the SRB3, the SN may communicate directly with the UE without going through the MN.

Example embodiment 2

This embodiment describes exemplary operations performed by the network regarding the management of SRBs (in particular, the release of lower layer resources of a split SRB on the SN and/or the release of SRB 3). In this embodiment, both MN and SN are included.

In some embodiments, after receiving a request from the MN to release lower layer resources of the MCG split SRB on the SN (or a procedure mimicking this), the SN releases the lower layer resources corresponding to the MCG split SRB. The SN then sends an acknowledgement to the MN as described in example embodiment 1. From the perspective of the MN, the MCG split SRB now becomes an MCG SRB in which only a set of lower layer resources are configured on the MN.

Special cases of SRB3

With the established SRB3, the SN may communicate directly with the UE via the Uu interface to facilitate its release. The SN may decide to release one or more SRBs 3 based on certain conditions. The condition may be at least one of:

1) the SN receives a request from the MN to release lower layer resources corresponding to all SN-side DRBs.

2) The SN requests release of lower layer resources corresponding to all the SN-side DRBs, and the MN acknowledges the request.

3) The lower layer resources corresponding to all DRBs on the SN have been released.

4) The SN receives a request from the MN to release lower layer resources corresponding to all DRBs and all MCG split SRBs.

5) The SN requests release of lower layer resources corresponding to all DRBs and all MCG split SRBs, and the MN acknowledges the request.

6) The lower layer resources corresponding to all DRBs and all MCG split SRBs have been released.

7) The SN receives a message to release the SCG.

In some embodiments, after determining that one of the conditions has been triggered, the SN first sends a request to the UE indicating the release and waits for an acknowledgement from the UE before releasing the SRB 3.

In some embodiments, the SN releases one or more SRBs 3 after one of its decision conditions has been triggered. For example, after receiving a request to release SCG from MN (or initiating a process to do so), if there are any established DRB(s) and/or split SPB(s) on the SN, the SN releases lower layer resources corresponding to all DRBs and split SRBs. The SN may release the SCG RLC bearers corresponding to all DRBs. In some embodiments, the SN further releases lower layer resources corresponding to any MCG split SRBs. The SN may also decide to release one or more SRBs 3 if there are any SRBs 3 configured on the SN.

Note that the release of SRB3 includes releasing lower level resources corresponding to SRB 3. In some embodiments, the release of SRB3 also includes releasing higher layer resources. That is, once SRB3 is released, both lower layer resources and upper layer resources are released.

Example embodiment 3

This embodiment describes an exemplary signaling procedure between the network and the UE regarding the management of the SRB, in particular the release of lower layer resources of the SRB. In this embodiment, the network includes both the MN and the SN.

Fig. 6 is a flowchart representation of a method 600 for wireless communication. The method 600 includes operating a wireless communication node in a wireless network at 602. The wireless network includes a master cell group and at least one secondary cell group. The method also includes sending, from the wireless communication node to the mobile device, a message indicating a release of the secondary cell group or a release of one or more signaling radio bearers for the secondary cell group, at 604.

In some embodiments, after the SN releases all DRBs and SRBs as described in example embodiment 2, the MN sends a message (e.g., RRC message) to the UE indicating the release of SCG so that the UE can also release SCG. The message may include an information element such as "to release secondary cell group list". The message may also include a group identifier (e.g., CellGroupId) that identifies the current cell of the SN.

Special cases of SRB3

In some embodiments, after the SN determines to release one or more SRBs 3, the SN may perform the following steps:

step E.1: the SN sends a message (e.g., an RRC message) to the UE via the Uu interface. The message includes an information element indicating the release of one or more SRBs 3.

Step E.2: the SN receives an RRC response message from the UE via the Uu interface. This message confirms the release of SRB 3.

The SN may then release SRB3 accordingly. However, in some embodiments, the RRC response message indicates that the UE refuses to release the one or more SRBs 3. In this case, the SN will not release one or more SRBs 3.

Example embodiment 4

Embodiments describe exemplary operation of a UE after the UE receives a message from a network to release a cell group. The releasing of the cell group includes releasing lower layer resources of the cell group.

Fig. 7 is a flowchart representation of a method 700 for wireless communication. The method 700 includes, at 702, receiving a message from a communication node in a wireless network indicating a release of lower layer resources associated with a group of cells in the wireless network. The method 700 includes releasing lower layer resources of a cell group at 704. The method 700 further includes avoiding one or more failures to monitor the group of cells at 706. For example, the failure of the SCG may include one or more of: SCG RLF, SN change failure, or SCG reconfiguration with synchronization failure.

More specifically, the UE may perform the following operations with respect to releasing one or more SRBs:

step F.1: the UE receives a message (e.g., an RRC reconfiguration message) from the network.

Step F.2: the UE reads the message. If the message includes an information element indicating the release of the SCG (e.g., "to-release secondary cell group list"), the UE releases the SCG. In particular, the UE releases lower layer resources of the SCG.

Step F.3: the UE stops monitoring SN signal quality and also stops detecting and/or reporting SCG failures when one of the following conditions is detected:

1) the message includes an information element to release SCG.

2) This message indicates the release of all SN-side DRBs.

3) This message indicates the release of all SN-side DRBs and SRBs (including SRB1S, SRB2S, and SRB 3).

Note again that while the foregoing description focuses on MCG split SRBs, the disclosed techniques may also be applied to split RBs configured for SCG (e.g., split RBs having lower layer resources configured on both MN and SN and higher layer resources configured only on SN).

Fig. 8 illustrates an example of a wireless communication system in which techniques in accordance with one or more embodiments of the present technology may be applied. The wireless communication system 800 may include one or more Base Stations (BSs) 805a, 805b, one or more wireless devices 810a, 810b, 810c, 810d, and a core network 825. Base stations 805a, 805b can provide wireless service to wireless devices 810a, 810b, 810c, and 810d in one or more wireless sectors. In some embodiments, base stations 805a, 805b include directional antennas to generate two or more directional beams to provide wireless coverage in different sectors.

The core network 825 may communicate with one or more base stations 805a, 805 b. The core network 825 provides connection with other wireless communication systems and wired communication systems. The core network may include one or more service subscription databases to store information about subscribed wireless devices 810a, 810b, 810c, and 810 d. The first base station 805a may provide wireless service based on a first radio access technology, and the second base station 805b may provide wireless service based on a second radio access technology. Depending on the deployment scenario, base stations 805a and 805b may be co-located in the field or may be separately installed in the field. Wireless devices 810a, 810b, 810c, and 810d may support multiple different radio access technologies.

In some embodiments, a wireless communication system may include multiple networks using different wireless technologies. Dual-mode or multi-mode wireless devices include two or more wireless technologies that can be used to connect to different wireless networks.

Fig. 9 is a block diagram representation of a portion of a radio station. A radio station 905, such as a base station or wireless device (or UE), may include processor electronics 910, such as a microprocessor, that implement one or more of the wireless technologies presented in this document. The radio station 905 may include transceiver electronics 915 to transmit and/or receive wireless signals over one or more communication interfaces, such as an antenna 920. The radio station 905 may include other communication interfaces for transmitting and receiving data. The radio station 905 may include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 910 can include at least a portion of the transceiver electronics 915. In some embodiments, at least some of the disclosed techniques, modules, or functions are implemented using a radio station 905.

It is therefore apparent that a method and corresponding apparatus relating to the management of one or more SRBs is disclosed. The disclosed techniques allow a UE operating in DC or MC mode to skip SN failure detection and/or SN signal quality monitoring of SNs when necessary, thereby reducing the bandwidth and power consumption of the UE.

From the foregoing, it will be appreciated that specific embodiments of the presently disclosed technology have been described herein for purposes of illustration, but that various modifications may be made without deviating from the scope of the invention. Accordingly, the presently disclosed technology is not limited, except as by the appended claims.

The disclosed and other embodiments, modules, and functional operations described in this document may be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this document and their structural equivalents, or in combinations of one or more of them. The disclosed and other embodiments may be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a computer-readable medium for execution by, or to control the operation of, data processing apparatus. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter effecting a machine-readable propagated signal, or a combination of one or more of them. The term "data processing apparatus" encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question (e.g., code that constitutes processor firmware), a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus.

A computer program (also known as a program, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

The processes and logic flows described in this document can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. However, a computer does not necessarily have such a device. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and storage devices, including by way of example: semiconductor memory devices such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

Although this patent document contains many specifics, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this patent document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings 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. Moreover, the separation of various system components in the embodiments described in this patent document should not be understood as requiring such separation in all embodiments.

Only some embodiments and examples are described and other embodiments, enhancements and variations can be made based on what is described and illustrated in this patent document.