阅读说明：本技术 速率调整技术 (Rate adjustment technique ) 是由 戴谦 黄河 董霏 马子江 艾建勋 于 2018-06-21 设计创作，主要内容包括：所公开的技术使得通信节点能够执行速率调整。作为示例,通信节点可以从网络节点接收控制信息。基于所接收的控制信息,控制节点可以确定网络节点支持编解码适配,或者确定通信节点被允许启用编解码适配。(The disclosed technology enables a communication node to perform rate adjustment. As an example, the communication node may receive control information from a network node. Based on the received control information, the control node may determine that the network node supports codec adaptation or that the communication node is allowed to enable codec adaptation.)

1. A method of wireless communication, the method comprising:

receiving, by a communication node, control information from a network node; and is

Based on the control information, determining that the network node supports codec adaptation or that the communication node is allowed to enable the codec adaptation.

2. The wireless communication method of claim 1, wherein the control information comprises information indicating that the codec adaptation is enabled or disabled for each transmission direction, each one or more packet data unit, PDU, sessions, each one or more quality of service, QoS, flows, each one or more data radio bearers, DRBs, or each one or more logical channels, LCHs.

3. The wireless communication method of claim 2, further comprising:

the communication node excludes one or more PDU sessions, one or more QoS flows, one or more DRBs, or one or more LCHs that are not capable of performing codec adaptation when generating the recommended bit rate query.

4. The wireless communication method of claim 1, wherein the control information comprises information indicating a bitrate adjustment range for the codec adaptation.

5. The wireless communication method of claim 4, wherein the communication node generates a recommended bitrate query by including a bitrate that does not exceed the bitrate adjustment range.

6. The wireless communication method of claim 1, wherein the control information comprises information indicating that the network node supports or does not support a time window for codec adaptation.

7. The wireless communication method of claim 1, wherein the control information comprises information indicating a time window for which codec adaptation is enabled or disabled for the communication node.

8. The wireless communication method of claim 1, further comprising:

in response to determining, based on the received control information, that the network node does not support codec adaptation or that the communication node is not allowed to enable the codec adaptation, performing any one or more of:

determining that a recommended bit rate query is not to be sent to the network node, an

It is determined that a recommended bit rate query is not generated.

9. A method of wireless communication, the method comprising:

sending, by a first network element, a message comprising adaptation control information to a second network element, the adaptation control information comprising an indication that the second network element is enabled or disabled for codec adaptation or that the second network element is allowed to enable codec adaptation for a communication node, and wherein the first network element and the second network element are separate network elements.

10. The wireless communication method according to claim 9, wherein the message comprises information indicating that the codec adaptation is enabled or disabled for each transmission direction of the second network element or for each transmission direction of the communication node.

11. The wireless communication method of claim 9, wherein the message comprises information indicating enabling or disabling the codec adaptation for each one or more Packet Data Unit (PDU) sessions, each one or more quality of service (QoS) flows, each one or more Data Radio Bearers (DRBs), or each one or more Logical Channels (LCHs).

12. The wireless communications method of claim 9, wherein the message includes information indicating a target code rate or a target code rate range for any one or more of each communication node, each one or more PDU sessions, each one or more Qos flows, each one or more DRBs, or each one or more LCHs.

13. The wireless communication method of claim 9, wherein the message comprises information indicating a time window within which codec adaptation is to be enabled or disabled.

14. The wireless communication method of claim 9, wherein the first network element comprises a centralized unit and the second network element comprises a distributed unit.

15. The wireless communication method of claim 9, wherein the first network element comprises a primary node and the second network element comprises a secondary node.

16. A method of wireless communication, comprising:

sending, by a first network element, a request message to a second network element, wherein the request message informs the second network element to enable or disable codec adaptation, and wherein the first network element and the second network element are separate network elements.

17. The wireless communication method of claim 16, wherein a first network node sends an indication to a second network node that the first network node implemented codec adaptation for a communication node.

18. The wireless communication method of claim 16, wherein the request message comprises information indicating that the codec adaptation is to be enabled or disabled for each transmission direction of the first network element or for each transmission direction of a communication node.

19. The wireless communications method of claim 16, wherein the request message includes information indicating that the codec adaptation is to be enabled or disabled for each one or more Packet Data Unit (PDU) sessions, each one or more quality of service (QoS) flows, each one or more Data Radio Bearers (DRBs), or each one or more Logical Channels (LCHs).

20. The wireless communications method of claim 16, wherein the request message includes information indicating a target code rate or a target code rate range for any one or more of each communication node, each one or more PDU sessions, each one or more Qos flows, each one or more DRBs, or each one or more LCHs.

21. The wireless communication method of claim 16, wherein the request message includes information indicating a time window within which codec adaptation is to be enabled or disabled.

22. The wireless communication method of claim 16, further comprising:

receiving, by the first network element, a recommended bitrate query comprising a recommended bitrate from a communication node, wherein the request message comprises the recommended bitrate query.

23. The wireless communication method of claim 22, further comprising:

sending, by the first network element, the recommended bitrate query to the second network element.

24. The wireless communication method of claim 16, wherein the first network element comprises a distributed unit and the second network element comprises a centralized unit.

25. A method of wireless communication, the method comprising:

receiving, by a network node, service type information adapted for a communication node codec, wherein the network node receives the service type information from the communication node or from a core network.

26. The wireless communication method of claim 25, wherein the core network is configured to provide the service type information to the communication node.

27. The wireless communications method of claim 25, wherein the service type information includes information identifying one or more Packet Data Unit (PDU) sessions or one or more quality of service (QoS) flows that support codec adaptation.

28. The wireless communications method of claim 25, wherein the service type information includes codec-adapted bit rate adjustment range supported by a Packet Data Unit (PDU) session or quality of service (QoS) flow.

29. A method of wireless communication, the method comprising:

receiving, by a first network element, a plurality of priorities of coverage enhancement from a second network element, the plurality of priorities including a priority of codec adaptation with respect to one or more priorities of one or more other coverage enhancements, and wherein the first network element and the second network element are separate network elements.

30. The wireless communication method of claim 29, wherein the first network element comprises a distributed unit and the second network element comprises a centralized unit.

31. The wireless communication method of claim 29, wherein the first network element comprises a user equipment and the second network element comprises a Radio Access Network (RAN) node.

32. A method of wireless communication, the method comprising:

sending, by the first network element, information to the second network element, the information comprising recommended bit rate information generated for or sent to the user equipment, or comprising recommended bit rate query information received by the first network element from the user equipment, wherein the user equipment is to be handed over.

33. The wireless communications method of claim 32, wherein the first network element comprises a source gNB and the second network element comprises a target gNB.

34. The wireless communication method of any of claims 16 or 29, wherein the first network element comprises a secondary node and the second network element comprises a primary node.

35. The wireless communication method according to claim 1 or 26, wherein the communication node comprises a user equipment and the network node comprises a radio access network, RAN, node.

36. An apparatus for wireless communication, the apparatus comprising a processor configured to implement the method of one or more of claims 1-35.

37. A computer readable program storage medium having code stored thereon, which when executed by a processor, causes the processor to implement a method according to one or more of claims 1 to 35.

Technical Field

The present disclosure relates generally to digital wireless communications.

Background

Mobile communication technology is pushing the world to an increasingly interconnected and networked society. Next generation systems and wireless communication technologies will need to support a much wider range of use case characteristics and provide a more complex and higher range of access requirements and flexibility than existing wireless networks.

Long-Term Evolution (LTE) is a standard developed by the third generation Partnership Project (3 GPP) for wireless communication of mobile devices with data terminals. LTE-Advanced (LTE-a) is a wireless communication standard that enhances the LTE standard. A fifth generation wireless system, referred to as 5G, advances the LTE and LTE-a wireless standards and is dedicated to support higher data rates, large numbers of connections, ultra-low latency, high reliability, and other emerging traffic needs.

Disclosure of Invention

Techniques are disclosed to enable bit rate adjustment between communication nodes. In a first example aspect, a method of wireless communication is disclosed. The method comprises the following steps: receiving, by a communication node, control information from a network node; and determining, based on the control information, that the network node supports codec adaptation or that the communication node is allowed to enable codec adaptation. In some embodiments, the control information includes information indicating that codec adaptation is enabled or disabled per transmission direction, per Packet Data Unit (PDU) session, per quality of service (QoS) flow, per Data Radio Bearer (DRB), or per Logical Channel (LCH).

In some embodiments, the method of the first example aspect comprises generating, by the communication node, the recommended bitrate query by excluding one or more PDU sessions, one or more QoS flows, one or more DRBs, or one or more LCHs that cannot perform codec adaptation.

In some embodiments, the control information comprises information indicating a bitrate adjustment range for codec adaptation. In some embodiments, the communication node generates the recommended bitrate query by including a bitrate that does not exceed the bitrate adjustment range.

In some embodiments, the control information comprises information indicating that the network node supports or does not support time windows for codec adaptation. In some embodiments, the control information comprises information indicating a time window for which codec adaptation is enabled or disabled for the communication node.

In some embodiments, the method of the first example aspect comprises, in response to determining, based on the received control information, that the network node does not support codec adaptation or that the communication node is not allowed to enable codec adaptation, performing any one or more of: determining that the recommended bit rate query is not sent to the network node, and determining that the recommended bit rate query is not generated.

In a second example aspect, a method of wireless communication is disclosed. The method comprises sending, by a first network element, a message comprising adaptation control information to a second network element, the adaptation control information comprising an indication that the second network element is enabled or disabled for codec adaptation or that the second network element is allowed to enable codec adaptation for a communication node, and wherein the first network element and the second network element are separate network elements.

In some embodiments, the message comprises information indicating that codec adaptation is enabled or disabled for each transmission direction of the second network element or for each transmission direction of the communication node. In some embodiments, the message includes information indicating that codec adaptation is to be enabled or disabled for each one or more Packet Data Unit (PDU) sessions, each one or more quality of service (QoS) flows, each one or more Data Radio Bearers (DRBs), or each one or more Logical Channels (LCHs). In some embodiments, the message comprises information indicating a target code rate or a target code rate range for any one or more of each communication node, each one or more PDU sessions, each one or more Qos flows, each one or more DRBs, or each one or more LCHs. In some embodiments, the message includes information indicating a time window within which codec adaptation is to be enabled or disabled.

In some embodiments of the second example aspect, the first network element comprises a centralized unit and the second network element comprises a distributed unit. In some embodiments of the second example aspect, the first network element comprises a primary node and the second network element comprises a secondary node.

In a third example aspect, a method of wireless communication is disclosed. The method comprises sending, by a first network element, a request message to a second network element, wherein the request message informs the second network element to enable or disable codec adaptation, and wherein the first network element and the second network element are separate network elements. In some embodiments, a first network node sends an indication to a second network node that the first network node implemented codec adaptation for a communication node.

In some embodiments, the request message comprises information indicating that codec adaptation is to be enabled or disabled for each transmission direction of the first network element or for each transmission direction of the communication node. In some embodiments, the request message includes information indicating that codec adaptation is enabled or disabled for each one or more Packet Data Unit (PDU) sessions, each one or more quality of service (QoS) flows, each one or more Data Radio Bearers (DRBs), or each one or more Logical Channels (LCHs). In some embodiments, the request message includes information indicating a target code rate or a target code rate range for any one or more of each communication node, each one or more PDU sessions, each one or more Qos flows, each one or more DRBs, or each one or more LCHs. In some embodiments, the request message includes information indicating a time window within which codec adaptation is to be enabled or disabled.

In some embodiments of the third example aspect, the method further comprises receiving, by the first network element, a recommended bitrate query comprising a recommended bitrate from the communication node, wherein the request message comprises information indicating that the first network element supports the recommended bitrate. In some embodiments of the third example aspect, the method includes sending, by the first network element, the recommended bit rate to the second network element. In some embodiments of the third example aspect, the first network element comprises a distributed element and the second network element comprises a centralized element.

In a fourth example aspect, a method of wireless communication is disclosed. The method comprises receiving, by a network node, service type information for codec adaptation of a communication node, wherein the network node receives the service type information from the communication node or from a core network. In some embodiments, the core network is configured to provide the service type information to the communication node. In some embodiments, the service type information includes information identifying one or more Packet Data Unit (PDU) sessions or one or more quality of service (QoS) flows that support codec adaptation. In some embodiments, the service type information includes a codec-adapted bit rate adjustment range supported by a Packet Data Unit (PDU) session or quality of service (QoS) flow.

In a fifth example aspect, a method of wireless communication is disclosed. The method includes receiving, by a first network element, a plurality of priorities of coverage enhancement from a second network element, the plurality of priorities including a codec-adapted priority of one or more priorities relative to one or more other coverage enhancements, and wherein the first network element and the second network element are separate network elements. In some embodiments of the fifth example aspect, the first network element comprises a distributed element and the second network element comprises a centralized element. In some embodiments of the fifth example aspect, the first Network element comprises a user equipment and the second Network element comprises a Radio Access Network (RAN) node.

In a sixth example aspect, a method of wireless communication is disclosed. The method comprises sending, by the first network element, information to the second network element, the information comprising information of a recommended bit rate generated for or sent to the user equipment, or recommended bit rate query information received by the first network element from the user equipment, wherein the user equipment is to be handed over. In some embodiments, the first network element comprises a source gNB and the second network element comprises a target gNB.

In some embodiments of the various aspects, the first network element comprises a secondary node and the second network element comprises a primary node. In some embodiments of the various aspects, the communication node comprises a user equipment and the network node comprises a Radio Access Network (RAN) node.

In yet another exemplary aspect, the above-described method is embodied in the form of processor executable code and stored in a computer readable program medium.

In yet another exemplary embodiment, an apparatus configured or operable to perform the above method is disclosed.

The above aspects and other aspects and embodiments thereof are described in more detail in the accompanying drawings, the description and the claims.

Drawings

Fig. 1 shows an example of a general architecture of a 5G RAN.

Fig. 2 shows an example of a Dual Connectivity (DC) architecture of the New Radio (NR) system.

Fig. 3 shows an example of a User Equipment (UE) receiving codec adaptation control information from a Radio Access Network (RAN) node.

Fig. 4 illustrates another example of a UE receiving codec adaptation control information from a RAN node.

Fig. 5 shows an example of a UE sending control information to a RAN node.

Fig. 6 shows an example in which a Centralized Unit (CU) transmits codec adaptation control information to a Distributed Unit (DU).

Fig. 7 shows an example in which the DU sends codec adaptation control request information to the CU.

Fig. 8 shows another example of the DU sending codec adaptation control request information to the CU.

Fig. 9 shows an example of a UE establishing a connection with a network node.

Fig. 10 shows an example of a UE requesting service type information for codec adaptation from a network node.

Fig. 11 shows an example of a first network node requesting service type information for codec adaptation from a second network node.

Fig. 12 shows an example of a flow chart for a handover procedure.

Fig. 13 is an example of a process used by a primary node (MN) to send codec adaptation control information to a Secondary Node (SN).

Fig. 14 is an example of a procedure for requesting codec adaptation control information from a MN by a SN.

Fig. 15 is another example of a procedure for requesting codec adaptation control information from a MN by a SN.

Fig. 16 illustrates an exemplary flow chart for receiving control information.

Fig. 17 shows an exemplary block diagram of a communication node or a network node.

Detailed Description

This patent document first provides an overview of a 5G Radio Access Network (RAN). Next, this patent document discusses some of the problems associated with the current application layer rate adjustment procedure for multimedia telephony service (MMtel). Hereinafter, the patent document describes various solutions in six sections. At least some of the solutions of section 1 generally involve enabling control mechanisms between a network node (such as a RAN node) and a communication node (such as a UE). At least some of the solutions of section 2 generally involve enabling a control mechanism between a first network element, such as a Distributed Unit (DU), and a second network element, such as a Centralized Unit (CU), where the DU and CU are separate. At least some of the solutions of section 3 typically involve enabling a control mechanism between the first network node (such as the RAN node) and the core network. At least some of the solutions of section 4 generally relate to prioritization control information sent between network elements or network nodes. At least some of the solutions of section 5 generally involve handover procedures. At least some of the solutions of section 6 generally involve enabling a control mechanism between the primary node and the secondary node. The following example headings of the sections are provided to aid in understanding the disclosed subject matter and are not intended to limit the scope of the claimed subject matter in any way. Thus, one or more features of one example section may be combined with one or more features of another example section.

The 5G New Radio (NR) protocol has introduced a dual connectivity system that may include two 5G-NR base stations being connected by a UE at the same time, or one LTE base station and one 5G-NR base station being connected by a UE at the same time. Currently, while developing 5G-NR, application layer bit rate adjustment procedures are required due to issues of network coverage or Radio Access Network (RAN) congestion. As further explained in various embodiments in this patent document, the development of the bit rate adjustment process may include a wireless handshake process of single link rate adjustment, a bit rate adjustment method of the Secondary Node (SN) or the primary node (MN) in inter-node Dual Connectivity (DC), and a code rate adjustment method of the internal Centralized Unit (CU), the internal Distributed Unit (DU), DC, SN or MN.

The section headings are used in this document to improve readability, and not to limit the embodiments and techniques described in the sections to only the sections.

Overall architecture of a 5G Radio Access Network (RAN)

Fig. 1 shows an example of the overall architecture of a 5G RAN. At the top of fig. 1, the acronym 5GC refers to the core network of a 5G network. The lower half of fig. 1 shows a NG RAN, which is referred to as a 5G new Radio Access Technology (RAT) radio access network. The NG-RAN is composed of a set of one or more gnbs connected to the 5GC through the NG interface. The gNB is a base station of a 5G RAN. The gNB may support Frequency Division Duplex (FDD) mode, Time Division Duplex (TDD) mode, or dual connectivity mode operation. The group of gnbs may be interconnected by an Xn interface. The gNB may be composed of a gNB-CU and one or more gNB-DUs. The gNB-CU and gNB-DU are connected via an F1 interface. NG, Xn, and F1 are logical interfaces used in the network.

In the New Radio (NR) framework, the forward network interface may be partitioned by taking into account transmission capacity, transmission delay, and/or ease of deployment. For example, considering non-ideal forward transmissions, the delay-insensitive network functions may be placed on a network element such as a Centralized Unit (CU), while the delay-sensitive network functions may be placed on another network element such as a Distributed Unit (DU).

In fig. 1, the left gNB is not divided into CUs and DUs, and the right gNB is divided into CUs and DUs. The decision whether to split the gNB may be based on the operator's network deployment requirements. An example of the division of CU and DU functions in a Protocol stack is that a CU may include Radio Resource Control (RRC) and Packet Data Convergence Protocol (PDCP) functions, while a DU includes RLC, MAC and PHY functions.

Fig. 2 shows an example of a Dual Connectivity (DC) architecture of an NR system. The DC system may include two (or more) network side nodes that provide data connections to or from the UE. For example, the network nodes may include a primary node and a secondary node. As another example, the network nodes in the DC system may include enbs and gnbs or other types of serving network nodes that provide wireless connectivity to UEs. In a DC system, for a UE with multiple transceivers (multiple Rx/Tx), the current serving base station of the UE in the NG-RAN, such as the first network element in fig. 2, may select a suitable radio channel for the UE. For example, the first network element may select a radio channel having a quality that meets or exceeds a certain threshold. In a DC system, a second base station (such as the second network element in fig. 2) may also be added to the UE. In a DC system, two base stations may collectively provide radio resources for a UE to perform user plane data transmission. Further, in terms of a wired interface, a first NG control plane (NG-C) may be established between the first network element and a next generation core network (NG-CN), and at most a NG-U may be established for the UE between the second network element and the NG-CN. The first network element and the second network element may be connected via an ideal or non-ideal interface, referred to as an Xn interface.

The first network element and the second network element may provide the same or different Radio Access Technologies (RATs) as well as relatively independent UE scheduling in terms of radio interface. Therein, the first network element connected to the control plane of the core network may be referred to as a master node and the core network may have only user plane connections, even though in some cases there may be no user plane connection with the core network. The second network element may be referred to as an auxiliary node. If there are more than two network elements connected to the UE, all nodes except the primary node are referred to as secondary nodes.

Based on the dual connectivity concept described above, multi-RAT dual connectivity refers to a dual connectivity architecture, where the primary and secondary nodes may be access points of different radio access technologies. For example, one access point may be an NR RAN node (e.g., a gNB) and another access point may be an LTE RAN node (eNB). In this example, the eNB and the gNB may be connected to the 5G core network simultaneously. In another example, a dual connectivity scenario may include both the primary node and the secondary node as NR RAN nodes (e.g., a gNB).

Application layer rate adaptation

Multimedia telephony services (MMtel) include voice and video services according to different communication needs. MMtel may provide end-to-end voice and video services between a first network node (such as a first UE) and a second network node (such as a second UE or computer). The application layer of the network node has a plurality of selectable code rates such that two network nodes can negotiate at the software application layer using the code rates. When the communication environment becomes worse or better, the network node may negotiate to decrease or increase the application layer code rate. However, since the code rate negotiated by the application layer does not necessarily match the actual communication environment of the network, it may conflict with the actual requirements of the network. For example, there may be several reasons why a voice or video session may get stuck. Some of these reasons may include cracking of the radio environment, or congestion at the RAN or core network.

In addition, the functions of bit rate adjustment and existing coverage enhancement functions of various other access networks are effectively duplicated. For example, the replication may specifically include PDCP replication, an overlap enhancement mechanism of subframes at the physical layer, or a dual connectivity mechanism. If the UE application layer arbitrarily adjusts the application layer code rate, it may cause the radio interface efficiency of the RAN to decrease. Therefore, the control mechanism for application layer rate adjustment should be considered at the RAN level as described.

1. Control mechanism between UE and RAN for codec adaptation

Section 1 provides a solution for enabling a control mechanism for codec adaptation at a network-side radio interface between a network node (such as a RAN node) and a communication node (such as a UE).

Solution 1.1: the UE receives information from the RAN node:

the UE may obtain one of the following codec adaptation control information from the RAN node: (1) whether the RAN node supports codec adaptation, or (2) whether the UE is allowed to enable codec adaptation functions. Information on whether the RAN node supports codec adaptation may be obtained through system messages. The information on whether the UE is allowed to enable the codec adaptation function may be obtained through dedicated signaling or a medium access control element (MAC CE).

In some embodiments, the codec adaptation control information obtained by the UE from the RAN node may include: in case the RAN node supports codec adaptation, or in case the UE is allowed to enable codec adaptation functionality, whether the RAN node can provide a recommended bit rate that may not meet the Qos requirements of the UE. Some examples of recommended bit rates that do not meet Qos requirements may include: the UE receives from the RAN node a recommended bit rate of the bearer or Qos flows or LCHs that is lower than a Guaranteed Bit Rate (GBR) requirement of the bearer or Qos flows or LCHs, or the UE receives from the RAN node a recommended bit rate of the bearer or Qos flows that is higher than a Maximum Bit Rate (MBR) requirement of the bearer or Qos flows or LCHs.

In some embodiments, codec adaptation control information obtained by the UE from the RAN node may tell the UE whether to allow the UE to send codec adaptation bit rate queries to the RAN node in certain cases. For example, the codec adaptation control information may inform the UE, which may send a codec adaptation or a recommended bit rate query to the RAN node that may not meet Qos requirements of one or more bearers. Another example may be that the UE may send a codec adaptation bit rate query to the RAN node that fails to satisfy the Qos flow or LCH of the UE.

In some embodiments, in which the UE is simultaneously connected with the primary node or the secondary node, the UE may obtain codec adaptation control information from the primary node, the information including whether the UE is allowed to perform codec adaptation with the secondary node. If the UE is not allowed to perform codec adaptation with the secondary node, the UE may not generate or send a recommended bit rate query to the secondary node.

In some embodiments, the codec adaptation control information obtained by the UE from the RAN node may include fine-grained control information including whether codec adaptation is enabled or disabled for any one or more of: each direction (e.g., uplink or downlink), each or more Packet Data Unit (PDU) sessions, each or more quality of service (QoS) flows, each or more Data Radio Bearers (DRBs), or each or more Logical Channels (LCHs). In some embodiments, the fine-grained control information for codec adaptation may include a bitrate adjustment range for codec adaptation.

Furthermore, the control information acquired by the UE from the RAN node may optionally include additional information, such as information indicating a time window of the RAN node supporting codec adaptation, or enabling/disabling the time window of codec adaptation for the UE. This information indicates, for example, when and for how long the RAN node supports codec adaptation, or the UE is enabled/disabled codec adaptation.

In some embodiments, if the RAN node does not support codec adaptation or the RAN node does not allow the UE to enable codec adaptation, the UE may perform any one or more of the following: (1) the UE may not send the recommended bit rate query to the RAN node if the recommended bit rate query has been generated, and (2) the UE may not generate the recommended bit rate query to send to the RAN node.

The UE sends a recommended bit rate query to the RAN node to provide the RAN node with a particular code rate recommendation value for the logical channel. Thus, the UE may use the recommended bitrate query to determine whether the RAN node can provide a bitrate recommendation value, or the UE requests the RAN node to indicate a bitrate recommendation value determined by the RAN node.

In some embodiments where the UE communicates with another communication node, such as another UE or a Multimedia Gateway (MGW), the first UE may inform the other communication node about the codec adaptation control information of the RAN node. In such embodiments, the notification method may comprise the UE using higher layers to send control information to the network node. For example, the UE may use non-access (NAS) layer signaling, the UE may forward control information to another communication node through a core network, or the UE may send control information to another communication node through an application layer.

In some embodiments, if the information obtained by the UE from the RAN node indicates that the RAN node supports (or does not support) codec adaptation or indicates a time window for enabling or disabling the codec adaptation function of the UE, the UE may perform the operations described in section 1.1 within the time window.

In some embodiments as described above where the UE control information includes fine-grained control information for codec adaptation, the UE may then perform any one or more of the following operations: (1) the UE may not include the one or more PDU sessions, one or more QoS flows, one or more DRBs, or one or more LCHs that are not capable of performing codec adaptation when generating the recommended bitrate query, and/or (2) it may not exceed a bitrate adjustment range indicated by a RAN node (such as a gNB) when the UE generates the recommended bitrate query.

Example 1 of solution 1.1

Fig. 3 shows an example of a UE receiving codec adaptation control information from a RAN node. A RAN node (such as a gNB) may use system messages (such as system information blocks) to broadcast codec adaptation control information to one or more UEs in the coverage area of the gNB. The system information block may include codec adaptation control information. The codec adaptation control information may indicate to the UE whether the codec adaptation function is supported.

In some embodiments, if the UE knows that the gNB supports the codec adaptation function, the UE may perform the following actions whether in the RRC idle state or in the RRC connected state: (1) if the codec adjustment request is obtained from a peer UE or a peer Media Gateway (MGW), the UE may generate and send a recommended bitrate query to the gNB asking the gNB whether it can provide the codec adjustment bitrate included in the query; or (2) if the UE measures that the quality of the air interface does not meet the preset threshold, the UE may generate and send a bit rate query to the gNB and ask the gNB whether it can provide the codec adjustment bit rate indicated by the gNB.

In some embodiments, if the UE determines from the system information that the gNB does not support the codec adaptation function, the UE may perform the following actions: (1) the UE may not send the recommended bit rate query to the RAN node if the recommended bit rate query has been generated; or (2) the UE does not generate a recommended bit rate query for the corresponding RAN node.

Alternatively, the UE may inform the second communication node (such as another UE or MGW) of the acquired codec adaptation control information of the RAN node. In this patent document, a UE and a second communication node may communicate with each other. For example, the UE and the second communication node may be engaged in a voice or video session. The UE may inform the second communication node using a route that may be through the application layer or through a NAS message. For example, the UE may send a NAS message to the core network including the acquired codec adaptation control information of the RAN node and the core network forwards it to the second communication node.

The codec adaptation control information sent by the gNB through the system message may have fine-grained control information, which may include: (1) each direction (e.g., whether uplink codec adaptation is supported and/or whether downlink codec adaptation is supported); (2) coding and decoding adaptive bit rate adjustment range; and/or (3) codec adaptation control time window. Based on finer grained control, the behavior rules of the UE may include: (1) the UE may implement any one or more of the operations described above in example 1 of solution 1.1 if the information acquired by the UE from the RAN node also includes a time window having a time window indicating the RAN node that supports or does not support information of codec adaptation or within which codec adaptation functions of the UE are enabled or disabled.

Furthermore, if the information obtained by the UE from the RAN node is fine-grained control information for codec adaptation, e.g. if one or more PDU sessions indicating that codec adaptation cannot be performed are indicated in the control information of codec adaptation or Qos flows or DRBs or LCHs, the UE may perform any one or more of the following: (1) if the UE generates a recommended bitrate query, it may not include a direction in which codec adaptation cannot be performed, a PDU session or QoS flow, or a DRB or LCH; (2) if the UE generates a recommended bit rate query, it may not exceed the bit rate adjustment range indicated by the gNB.

Example 2 of solution 1.1

Fig. 4 shows another example of a UE receiving codec adaptation control information from a RAN node. The gNB may send codec adaptation control information included in the RRC reconfiguration message to the UE. The gNB may perform codec adaptation control for a single UE. In the 3GPP system, the configuration information may be transmitted to a specific UE through an RRC message or a MAC CE, and codec adaptation control information may be carried therein.

The form of codec adaptation control information for a single UE may include finer grained control information, including any one or more of the following (in addition to the fine grained control information described in example 1 of solution 1.1): (1) one indication indicating that the UE enables or disables codec adaptation; (2) an indication of whether the UE is capable of enabling uplink or downlink codec adaptation; (3) one or more PDU sessions, or one or more QoS flows, or one or more DRBs, or LCHs that can enable or disable codec adaptation; (4) coding and decoding adaptive bit rate adjustment range; and/or (5) codec adaptation control time window.

The UE may obtain the codec adaptation control information, and the UE may perform the operations discussed next. From the information discussed above, if the RAN node does not support codec adaptation or the RAN node does not allow the UE to enable codec adaptation, the UE may perform any one or more of the following operations: (1) the UE may not send the recommended bit rate query to the RAN node if the recommended bit rate query has been generated; (2) the UE may not generate a recommended bit rate query for the corresponding RAN node.

Furthermore, the UE may inform a second communication node (such as another UE or MGW) about the codec adaptation control information of the RAN node. In some embodiments, the notification method used by the UE may comprise the UE sending codec adaptation control information to the second communication node using NAS layer signaling. The NAS layer signaling is forwarded to the second communication node through the core network. In some embodiments, the notification method may include the UE sending codec adaptation control information to the second communication node using an application layer.

If the information obtained by the UE from the RAN node also includes a time window within which the RAN node supports or does not support codec adaptation, or a time window within which the codec adaptation function of the UE is enabled or disabled, the UE may perform one or more operations within said time window as described above in example 2 of solution 1.1. If the information obtained by the UE from the RAN node is fine-grained control information for codec adaptation, e.g., if a direction (e.g., uplink or downlink) in which codec adaptation cannot be performed is indicated in the control information of codec adaptation, one or more PDU sessions, or QoS flows, or DRBs or LCHs, the UE may perform one or more of the following: (1) if the UE generates a recommended bitrate query, the query may not include a direction in which codec adaptation cannot be performed, a PDU session or QoS flow, or a DRB or LCH; or (2) if the UE generates a recommended bit rate query, the recommended bit rate may not exceed the bit rate adjustment range indicated by the gNB.

Solution 1.2: the UE sends information to the RAN node:

in some embodiments, if a first communication node (such as a UE) obtains request information for codec adaptation from a second communication node (such as a second UE or MGW) (e.g., via an application layer), the first communication node may send the request information for codec adaptation to its serving RAN node to which the first communication node is wirelessly connected to help the serving RAN node decide how to perform local codec adaptation. The first and second communication nodes may comprise user equipment or MGWs, and the first network node may comprise a RAN node (such as a gNB).

Example of solution 1.2

Fig. 5 shows an example of a UE sending request information to a RAN node serving the UE. The UE communicates with a second communication node (not shown in fig. 5). If the UE obtains from the second communication node request information for codec adaptation delivered by a RAN node connected to the second communication node, the UE may send a recommended bit rate query to its serving RAN node to which it is connected. The recommended bit rate query may include a request for codec adaptation information sent by the second communication node. Using the received request information, the serving RAN node may determine how to perform local codec adaptation.

2. Control mechanism between a Centralized Unit (CU) and a Distributed Unit (DU) for codec adaptation

Section 2 provides a solution for avoiding repeated implementation of codec adaptation and other coverage area enhancements, e.g. by having higher layers of the RAN node interact with the MAC layer of the RAN node. In the architecture with separate CUs and DUs, codec adaptation between CUs and DUs requires interactive control and reporting. In the CU and DU separated architecture, the operations described in the following solution in section 2 may be performed between the CU and the DU.

Solution 2.1: CU sends codec adaptation control information to DU

The codec adaptation control information includes one of the following information:

(1) whether the DU is enabled to support codec adaptation, and when the DU is not allowed to support codec adaptation, the DU may not generate and transmit recommended bit rate adjustment information for any connected UE; or

(2) Whether the DU is allowed to enable codec adaptation for a given UE. When not enabled, the DU may not generate and transmit recommended bit rate adjustment information for a given UE.

Further, the codec adaptation control information sent by the CU to the DU may include whether the DU can provide a recommended bit rate that may not meet the Qos requirements of the UE. Some examples of recommended bit rates that do not meet Qos requirements may include: the UE receives from the DU a recommended bit rate of the bearer or Qos flows or LCHs that is lower than a Guaranteed Bit Rate (GBR) requirement of the bearer or Qos flows or LCHs, or the UE receives from the DU a recommended bit rate of the bearer or Qos flows that is higher than a Maximum Bit Rate (MBR) requirement of the bearer or Qos flows or LCHs.

In some embodiments, codec adaptation control information that may be obtained by the UE from the DU may tell the UE whether to allow the UE to send a recommended bit rate query to the DU in some cases. For example, the codec adaptation control information may inform the UE, which may send a recommended bit rate query to the DU that may not meet Qos requirements of one or more bearers. As another example, the UE may send a recommended bit rate query to the DU that cannot satisfy the Qos flows or LCHs of the UE.

Optionally, the CU may also send the DU a time window within which codec adaptation is enabled or disabled. The DU informs the UE using the recommended bit rate information that the RAN needs to adjust the code rate for certain logical channels.

Further, codec adaptation control information sent by a CU to a DU may specify whether codec adaptation is enabled or disabled for each transmission direction (e.g., uplink or downlink). That is, whether DUs are enabled to enable uplink or downlink codec adaptation for each transmission direction, or whether uplink or downlink codec adaptation for a given UE for each transmission direction is enabled.

In some embodiments, the codec adaptation control information sent by the CU to the DU may include fine-grained control information, including whether codec adaptation is enabled or disabled for any one or more of: each one or more PDU sessions, or each one or more QoS flows, each one or more DRBs, or each one or more LCHs. With fine-grained control information, the DU can determine which PDU sessions, QoS flows, or DRBs or LCHs of the UE are allowed or not allowed to perform codec adaptation.

In some embodiments, the codec adaptation control information sent by the CU to the DU may include a target code rate or a target code rate range of the codec adjusted for each UE, each or multiple PDU sessions, each or multiple Qos flows, each or multiple DRBs, or each LCH. In some embodiments, the codec adaptation control information sent by a CU to a DU may also include a time window for codec adaptation control.

Example of solution 2.1

Fig. 6 shows an example of a gNB associated with a CU that sends codec adaptation control information to the gNB associated with a DU. As mentioned above, section 2 describes CUs separate from DUs. The content of the codec adaptation control information may include one of: (1) an indication of whether the DU is enabled or disabled to perform codec adaptation. When not enabled, the DU cannot generate and send recommended bit rate adjustment information for any connected UE. Alternatively, the CU may also send or enable codec adaptation to the DU. A functional time window; or (2) an indication of whether the DU enables codec adaptation for a given UE. When not enabled, the DU cannot generate and transmit recommended bit rate adjustment information for a given UE.

Further, the codec adaptation control information sent by the CU to the DU may specify the enabling or disabling of each user codec adaptation for a given UE. In some embodiments, the codec adaptation control information may indicate whether the DU is allowed to enable uplink or downlink codec adaptation, or whether codec adaptation is enabled for the uplink or downlink of a given UE, or whether codec adaptation for the given UE is enabled.

Furthermore, the codec adaptation control information sent from the CU to the DU for a given UE may have fine-grained control information, which may include control granularity of codec adaptation per PDU session, or per Qos flow, or per DRB or per LCH. Using this information, the CU can determine for which PDU sessions, or QoS flows, or DRBs, or LCHs, codec adaptation is or is not allowed for the UE. In some embodiments, the fine-grained control information may include a codec adaptation recommended bit rate or recommended bit rate range per UE, per PDU session, per Qos flow, per DRB, or per LCH. In some embodiments, the fine-grained control information may include a codec adaptation control validity time window.

The flow of coding and decoding the adaptation control information may be as follows: during the process of establishing the F1 interface with the DU, the CU may send codec adaptation control information to the DU. In establishing an RRC connection for a given UE, a CU may send codec adaptation control information for the given UE to a DU. During bearer establishment, a CU may send codec adaptation control information for a given UE to a DU. The CU may also send codec adaptation control information to the DU during any signaling that involves the CU to the DU.

Since the codec adaptation control information changes depending on the radio air interface communication quality, DU load, CN load dynamic conditions or additional factors, the codec adaptation control information belongs to a dynamically configured control information, which can be used in any CU-to-DU signaling in order to enhance its dynamics.

Solution 2.2: the DU sends the coding and decoding adaptation request information to the CU:

if the first network element (such as a DU) determines whether to perform codec adaptation, the first network element may send a codec adaptation request message to a second network element (such as a CU) to enable or disable codec adaptation. The codec adaptation request message may be per DU or for a given UE.

In some embodiments, if the DU generates or sends recommended bit rate information for a given UE, the DU may inform the CUs that the DU has implemented codec adaptation for the UE. This information may be sent in a request message, for example. The CU may decide based on this whether to implement other coverage enhancement mechanisms for the UE.

Further, the codec adaptation request message sent by the DU to the CU may request any one or more of the following: codec adaptation in each direction (e.g., uplink or downlink) is enabled or disabled for DUs or for a given communication node (such as a UE). In some embodiments, the receiving node is required to enable or disable codec adaptation if enabled or disabled codec adaptation is indicated in the request message.

In some embodiments, the codec adaptation request message sent by the DU to the CU may include fine-grained control information including whether codec adaptation is enabled or disabled for any one or more of the following for the UE: each or multiple PDU sessions, each or multiple QoS flows, each or multiple DRBs, or each or multiple LCHs. Using fine-grained control information, a CU can determine which PDU sessions or QoS flows or QoS or LCH are codec adaptations enabled or disabled for the UE.

In some embodiments, the DU may also include in the codec adaptation request message a target codec rate or target codec rate range for any one or more of per UE, per PDU session, per QoS flow, per DRB, or per LCH recommended by the DU.

In some embodiments, the codec adaptation request information sent by the DU to the CU may also include a time window in which the codec adaptation control request takes effect. The time window may indicate a time when codec adaptation is to be enabled or disabled. In some embodiments, if enabling or disabling of codec adaptation is indicated within a time window in the request message, the receiving node needs to enable or disable codec adaptation within said time window.

In some embodiments, if the DU receives a recommended bit rate query from the UE indicating that the UE wants to perform codec adaptation using the recommended bit rate, the DU sends the request information to the CU by including the recommended bit rate query of the UE.

Optionally, in some embodiments, the recommended bit rate query may be forwarded by the DU directly to the CU, or the DU forwards the recommended bit rate query to the CU by remapping LCHs in the recommended bit rate query to corresponding DRBs or Qos flows or PDU sessions.

Example 1 of solution 2.2

Fig. 7 shows an example in which the DU sends codec adaptation control request information to the CU. The contents of the codec adaptation request information may include one of the following information. If the DU wants or does not want to perform codec adaptation, the DU may send an indication to the CU in the request message to enable or disable codec adaptation, respectively. The request information may be per DU. Thus, the DU determines whether the DU wants to support or does not support performing codec adaptation for all UEs or whether it wants to support or does not support performing codec adaptation for a given UE. Further, the codec adaptation request information may include an indication to enable or disable codec adaptation in each direction (e.g., uplink or downlink). In addition, the codec adaptation request information may be per UE.

In some embodiments, the codec adaptation request information sent by the DU to the CU may have fine-grained control request information for the UE, including codec adaptation per PDU session, or per QoS flow, or per DRB or per LCH. With this information, the CU can determine which PDU sessions, or QoS flows, or DRBs, or LCHs, are enabled or disabled for codec adaptation of the UE. In some embodiments, the codec adaptation request information further includes a target code rate or target code rate range per UE, per PDU session, per Qos flow, per DRB, or per LCH as recommended by the DU. In some embodiments, the codec adaptation request message further includes a time window in which the codec adaptation control is in effect.

In some embodiments, an example of a process of transmitting the codec adaptation request information may be as follows. The DU sends codec adaptation request information to the CUs in the process of establishing the F1 interface with the CU. The DU may send codec adaptation request information for the given UE to the CU during establishment of the RRC connection for the given UE. The DU may send codec adaptation request information for a given UE to CUs during the bearer establishment procedure. The DU may also send codec adaptation request information to the CU in any signaling procedure involving the DU to the CU.

Example 2 of solution 2.2

Fig. 8 shows another example of the DU sending codec adaptation control request information to the CU. If the DU receives from the UE side requested bit rate query information indicating that the UE wishes to perform codec adaptation and may include a request that the UE obtain codec adaptation from the second communication node, the DU may send a codec adaptation request message to the CU to confirm whether it can support the information included in the UE's recommended bit rate query. In some embodiments, the recommended bit rate query received by the DU may include a codec adaptation request from a second communication node with which the UE communicates. Alternatively, the recommended bit rate query may be forwarded by the DU to the CU as part of the codec adaptation request message, or the DU remaps the LCH in the recommended bit rate query to the corresponding DRB or Qos flow, or PDU session, and then forwards the recommended bit rate query to the CU.

Example 3 of solution 2.2

In some embodiments, if the DU generates or sends recommended bit rate information for a given UE, the DU may inform the CUs that the DU has implemented codec adaptation for the UE. Based on the information received by the CU, the CU may determine whether it can implement other coverage enhancement mechanisms for the UE. The procedure of example 3 for solution 2.2 may be the same as the flowchart shown in fig. 7.

3. Control mechanism between RAN and CN for codec adaptation

Section 3 provides a solution for services that support codec adaptation. In current network architectures, only the core network and the UE can know which services support codec adaptation, and the RAN does not know which services support codec adaptation. In some cases, only the core network knows which services support codec adaptation, neither the UE nor the RAN knows which services support codec adaptation.

In some embodiments related to section 3, a network node (such as a RAN node) may obtain supported service type information for codec adaptation of a given UE from the CN or from the UE. The UE may obtain service type information for codec adaptation of the UE from the CN.

The service type information supported for codec adaptation of the UE may include information such as an identification of one or more PDU sessions of the UE or an identification of one or more QoS flows supporting codec adaptation. In some embodiments, the supported service type information may include a codec-adapted bit rate adjustment range supported by the PDU session or QoS flow.

In embodiments where the RAN node obtains supported service type information from the CN, the RAN node may obtain the supported service type information during a procedure of establishing a connection between the given UE and the RAN node and the CN. In some embodiments, the network node may obtain the supported service type information from the CN when the CN requests the RAN node to modify a PDU session or QoS flow for a given UE.

In embodiments where the RAN node obtains supported service type information from the UE, the RAN node may obtain the supported service type information during a procedure of establishing a connection between the given UE and the RAN node and the CN. In some embodiments of the present invention, the,

in embodiments where the UE obtains the supported service type information from the CN, the UE may obtain the supported service type information during a procedure of establishing a NAS connection between the UE and the CN. In some embodiments, the UE may obtain the supported service type information from the CN during PDU session establishment between the UE and the CN.

Example 1 of section 3

The RAN node, CN and UE may exchange some information during the establishment of a connection between the UE and the network. During the procedure of establishing the connection, the CN may send codec adaptation support service type information to the RAN. A communication node (such as a UE) may send supported service type information for codec adaptation to a RAN node. Alternatively, when the UE itself does not have service type information of codec adaptation, the CN may send codec adaptation support service type information of the UE to the UE in the process of establishing the connection between the UE and the CN.

The service type information supported for codec adaptation of the UE may include one or more PDU sessions of the UE or one or more QoS flows supporting codec adaptation. In some embodiments, the supported service type information of codec adaptation of the UE may further include a tunable range of codec adaptation supported by the PDU session or Qos flow.

Fig. 9 shows an example of a UE establishing a connection with a network node, such as a gNB. In example 1 of section 3, the UE stores its own service type information for codec adaptation. In the example scenario, the UE may adapt its own type of codec adaptation service in establishing an RRC connection between the UE and the RAN node. As shown in fig. 9, the UE may send supporting service type information for codec adaptation of the UE to the gNB using an RRC connection creation complete message. This message may be sent by the UE in response to the RRC connection setup message sent by the gNB. In some embodiments, other RRC signaling from the UE to the gNB may also be used to carry supporting service type information for codec adaptation of the UE.

Fig. 10 shows an example of a UE obtaining service type information for codec adaptation from a network node, such as a CN. In the embodiment related to fig. 10, the UE may not store its own service type information for codec adaptation. The CN may provide feedback in the course of the UE requesting one or more PDU sessions from a core network element, such as a Session Management Function (SMF), using a PDU session establishment request. The CN may send the UE's corresponding codec adaptation service type information in a feedback signal (such as in a PDU session setup request accept message). In some embodiments, the CN may send other signaling to the UE to carry supported service type information for codec adaptation of the UE.

Fig. 11 shows an example of a first network node (e.g., CN) sending service type information for codec adaptation to a second network node (e.g., gNB). In fig. 10, a network element of the CN (such as SMF) may send a PDU session resource setup request message for a given UE to the gNB. The request message sent by the CN may carry codec adaptation support service information of the UE to the gNB. In some embodiments, other signaling may be used by the CN to send the codec adaptation support service type information of the UE to the gNB.

4. Prioritization control information

Codec adaptation and other coverage enhancement schemes, such as replication, Coverage Enhancement (CE) mode, etc., may implement similar coverage enhancement at different costs. In section 4, different coverage enhancement schemes are described that may have implementation priority. Higher layers may set policies for the Medium Access Control (MAC) layer and prioritize those solutions to be implemented. This type of policy may be affected by network load or service type. Dynamic configuration may be implemented where policy priorities may differ in different situations.

In embodiments involving separate CU and DU architectures, the following operations may be performed by CUs and/or DUs. The CU may indicate to the DU a plurality of priorities of the coverage enhancement mechanism, which may include priorities of one or more priorities of the codec adaptation function relative to one or more other coverage enhancements. The priority indication of the coverage enhancement mechanism may be for the entire DU so that the DU may perform the same priority indication for one or more connected UEs. In some embodiments, the priority indicated by the coverage enhancement mechanism may be per communication node (such as a UE) such that the DU may perform priority indication for a given UE.

In embodiments involving dual connectivity architectures, the MN may send to the SN a priority indicated by the coverage enhancement mechanism for a given UE, where the priority of the codec adaptation function may be higher or lower than one or more priorities of one or more other coverage enhancement schemes.

In embodiments involving communication between the RAN node and the UE, the RAN node may send priority information to the UE, the priority information including a priority of one or more coverage enhancement schemes, the priority may include a priority of one or more priorities of a codec adaptation function relative to one or more other coverage enhancements. When the UE side simultaneously satisfies the trigger conditions of multiple coverage enhancement schemes, the UE may determine which coverage enhancement is preferentially performed according to the execution priority.

Coverage enhancement schemes may include dual connectivity, carrier aggregation replication, dual connectivity replication, bundling, replication in time zones (e.g., in frames), handover, Pcell or Scell changes, codec adaptation, and so on.

The priority indication of the coverage enhancement mechanism may comprise one of the following embodiment examples. As a first example, the network node can only indicate whether the codec adaptation function has a high priority. Table 1 shows a second example of priority indication for the coverage enhancement mechanism. As shown in table 1 below, a network node may include several coverage enhancements with priority levels.

Coverage enhancement mechanism	Priority level
		Codec adaptation	1
CE mode	2
		PDCP replication	3

TABLE 1

In a third example, the network node may include several coverage enhancement scenarios and give an ordering of the trigger conditions, as shown in table 2 below. The measurement result may include, for example, Reference Signal Received Power (RSRP) or Reference Signal Received Quality (RSRQ).

Coverage enhancement mechanism	Measurement results
		Codec adaptation	RSRQ Range 1
Configuring dual connectivity	RSRQ Range 2
		Handover	RSRQ Range 3

TABLE 2

5. Switching process

One of the problems solved by the solution in section 5 is whether the target gNB should get the old recommended bitrate or the old recommended bitrate query during the Handover (HO) procedure.

In some embodiments, during a HO procedure, a first network element (such as a source gNB) may send information to a second network element (such as a target gNB), which may include recommended bit rate information that was recently generated or sent to a UE being handed over, or recommended bit rate query information that was recently received by the source gNB from the UE to be handed over. In some embodiments, the information sent by the first network element to the second network element may be sent via a handover request message during handover.

Fig. 12 shows an example of a flow chart for a handover procedure. First, a communication node (such as a UE) sends a measurement report to a first network node (such as a source gNB). Based on the measurement report, the source gNB may determine whether to perform a handover. If the source gNB determines to perform a handover, the source gNB can send a handover request to a second network node (such as the target gNB). The handover request may include the last received recommended bit rate query information from the UE and/or the last generated recommended bit rate. Next, the target gNB may send a handover confirmation message to the source gNB, where the target gNB may respond to whether the received recommended bit rate or recommended bit rate query in the handover request message may be accepted or may need to be modified, and further, the modified recommended bit rate generated by the target gNB may also be included in the handover confirmation message sent to the source gNB, which may deliver it to the UE in, for example, a handover command message.

6. Control mechanism between MN and SN for codec adaptation

As mentioned above, the dual connectivity architecture may include a UE establishing connectivity with both a primary RAN node (MN) and a secondary RAN node (SN). The MN can control codec adaptation of the SN. In some embodiments, the MN may send codec adaptation control information to the SN. In some embodiments, the MN may send codec adaptation control information to the SN in response to the SN requesting a codec adaptation function from the MN.

The method for sending, receiving and processing codec adaptation control information is similar to an architecture where CUs or DUs are separated in a single connection. The MN and the SN can be considered as two network elements, where the MN can perform the operations described in section 2 for CUs and the auxiliary node can perform the operations described in section 2 for DUs. As mentioned above, the DU and CU may also be considered as a first network element and a second network element, respectively. The difference between the two is in the interface protocol. In the 3GPP protocol, the interface between MN and SN is an Xn interface, and the interface between CU and DU is an F1 interface.

The MN/SN method is similar to solution 2(CU/DU) above, i.e.: (1) the MN indicates codec adaptation control information to the SN, and/or (2) the SN indicates codec adaptation request information to the MN.

Fig. 13 is an example of a process used by a primary node to send codec adaptation control information to a secondary node. The MN may send a SN addition or SN modification or SN change request to the SN, which may include codec adaptation control information. The content of the codec adaptation control information may include any one or more of:

(1) whether the SN is allowed to enable codec adaptation for a given UE. When not enabled, the SN may not generate and send recommended bit rate adjustment information for a given UE.

(2) Whether codec adaptation is enabled or disabled in each direction (e.g., uplink or downlink) for a given UE.

In some embodiments, the codec adaptation control information sent by the MN to the SN may include whether the SN is capable of providing a recommended bit rate that may not meet the Qos requirements of the UE. Some examples of recommended bit rates that do not meet Qos requirements may include: the UE receives from the SN a recommended bit rate for the bearer or Qos flow or LCH that is lower than the Guaranteed Bit Rate (GBR) requirement of the bearer or Qos flow or LCH, or the UE receives from the SN a recommended bit rate for the bearer or Qos flow that is higher than the Maximum Bit Rate (MBR) requirement of the bearer or Qos flow or LCH.

In some embodiments, codec adaptation control information that may be obtained by the UE from the MN may tell the UE whether it is allowed to send to the SN a recommended bit rate query that may not meet the Qos requirements of the UE in certain circumstances. For example, the codec adaptation control information may inform the UE, which may send a recommended bit rate query to the SN that may not meet Qos requirements of one or more bearers. Another example may be that the UE may send a recommended bit rate query to the SN that is not able to satisfy the Qos flows or LCHs of the UE.

In some embodiments, the codec adaptation control information sent by the MN to the SN for a given UE may have fine-grained control information, including: codec adaptation per PDU session, or per QoS flow, or per DRB or per LCH. Using this information, the SN can determine which of the PDU session, QoS flow, DRB, or LCH is enabled or disabled for codec adaptation. In some embodiments, the fine grain control information may comprise a recommended bitrate or recommended bitrate range adapted for codec per UE, or per PDU session, or per QoS flow, or per DRB or per LCH. In some embodiments, the fine-grained control information may include a codec adaptation control validity time window.

The codec adaptation control information may be transmitted using any one of the following procedures:

(1) the MN can send codec adaptation control information to the SN during the process of establishing dual connectivity with the SN (such as by using an SN addition process);

(2) the MN can send codec adaptation control information for a given UE to the SN in a process to modify the SN (such as by using an SN modification process);

(3) the MN can send codec adaptation control information for a given UE to the SNs in the process of replacing the new SN (such as by altering the flow using the SN); or

(4) The MN can send codec adaptation control information to the SN in any signaling procedure involving the MN to the SN.

Since the codec adaptation control information may change according to the communication quality of the radio interface, the load of the SN, or other dynamic conditions, the codec adaptation control information may be dynamically configured. To enhance its dynamics, the codec adaptation control information may be carried in any message signaled by the MN to the SN.

Fig. 14 is an example of a procedure for requesting codec adaptation control information from a MN by a SN. The SN may send a SN modification request, a SN change, or a QoS notification message to the MN. The SN modification, SN change, or QoS notification message may include codec adaptation control information. The contents of the codec adaptation control information may include information such as whether the SN wants to perform codec adaptation or does not want to perform codec adaptation. The SN may send a request message to the MN to enable or disable codec adaptation for a given UE. In some embodiments, the codec adaptation request information may include a granularity for each direction, such that the request may indicate that uplink or downlink codec adaptation is enabled for a given UE.

In some embodiments, the codec adaptation request information sent by the SN to the MN may have a fine-grained control information request that may indicate codec adaptation per PDU session, or per QoS flow, or per DRB or per LCH. Using this information, the MN can determine which of PDU sessions, QoS flows, DRBs, or LCHs to enable or disable for codec adaptation. In some embodiments, the control information request may include a target code rate or target code rate range per UE, per PDU session, per Qos flow, per DRB, or per LCH recommended by the SN. In some embodiments, the control information request may include a time window in which the codec adaptation control takes effect.

The codec adaptation request information may be transmitted using any one of the following procedures:

(1) as part of the process of requesting SN modification from the MN, the SN may send codec adaptation request information to the MN;

(2) as part of the process of requesting an SN change from the MN, the SN may send codec adaptation request information to the MN;

(3) as part of the process of sending QoS notifications to alert the MN, the SN may send codec adaptation request information to the MN; or

(4) The SN may also send codec adaptation request information to the MN in any signaling procedure involving the SN to the MN.

Fig. 15 is another example of a procedure for requesting codec adaptation control information from a MN by a SN. If the SN receives recommended bit rate query information from the UE side indicating that the UE wishes to perform codec adaptation, the SN may deliver the recommended bit rate information to the MN to confirm whether the MN is capable of supporting the recommended bit rate query of the UE. In some embodiments, the recommended bit rate query information received by the SN may include a request for codec adaptation obtained by the UE from a peer communication node (such as another UE or MGW). Optionally, the recommended bit rate query may be forwarded by the SN to the MN, or the SN remaps the LCHs in the recommended bit rate query into corresponding DRBs or Qos flows or PDU sessions.

The following description provides another example of a procedure for requesting codec adaptation control information from a MN by a SN. If the SN generates or sends recommended bit rate information for a given UE, the SN may inform the MN that the SN has implemented codec adaptation for the UE. The MN may decide based on this whether to implement other coverage enhancement mechanisms for the UE.

Fig. 16 illustrates an exemplary flow chart for receiving control information. At receiving operation 1602, the communication node receives control information from the network node. The control information may include information indicating that codec adaptation is enabled or disabled per transmission direction, per one or more Packet Data Unit (PDU) sessions, per one or more quality of service (QoS) flows, per one or more Data Radio Bearers (DRBs), or per one or more Logical Channels (LCHs). In some embodiments, the communication node may generate the recommended bit rate query by excluding one or more PDU sessions, one or more QoS flows, one or more DRBs, or one or more LCHs that are not capable of performing codec adaptation.

The control information may include information indicating a bitrate adjustment range for codec adaptation. In some embodiments, the communication node generates the recommended bitrate query by including a bitrate that does not exceed the bitrate adjustment range. In some embodiments, the control information may comprise information indicating that the network node supports or does not support time windows for codec adaptation. In some embodiments, the control information may comprise information indicating a time window for which codec adaptation is enabled or disabled for the communication node.

At determining operation 1604, the communication node determines, based on the control information, that the network node supports codec adaptation or that the communication node is allowed to enable codec adaptation.

In some embodiments, the process shown in fig. 16 may further include the communication node determining, based on the received control information, that the network node does not support codec adaptation or that the communication node is not allowed to enable codec adaptation. In such embodiments, the communication node performs any one or more of the following operations: determining not to send the recommended bitrate query to the network node, and determining not to generate the recommended bitrate query.

Fig. 17 shows an exemplary block diagram of a communication node or network node 1700. Communication node 1700 may comprise a user equipment, a mobile device or a multimedia gateway. Network node 1700 may include a base station, a RAN node, a gNB, a primary node in a dual-connectivity system, a secondary node in a dual-connectivity system, a distributed unit, or a centralized unit. Communication or network node 1700 includes at least one processor 1710 and memory 1705 having instructions stored thereon. The instructions executed by processor 1710 configure communication or network node 1700 to perform the operations described in fig. 16 and in the various embodiments described in this patent document. The transmitter 1715 transmits or sends information or data to another network node or another communication node. Receiver 1720 receives information or data transmitted or sent by another network node or another communication node.

In this document, the term "exemplary" is used to mean an "… … example," and does not imply an ideal or preferred embodiment unless otherwise stated.

Some of the embodiments described herein are described in the general context of methods or processes, which may be implemented in one embodiment by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. The computer-readable medium may include removable and non-removable storage devices, including, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), Compact Disc (CD), Digital Versatile Disc (DVD), and the like. Thus, a computer-readable medium may include a non-transitory storage medium. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

Some of the disclosed embodiments may be implemented as a device or module using hardware circuitry, software, or a combination thereof. For example, a hardware circuit implementation may include discrete analog and/or digital components integrated as part of a printed circuit board, for example. Alternatively or additionally, the disclosed components or modules may be implemented as Application Specific Integrated Circuits (ASICs) and/or Field Programmable Gate Array (FPGA) devices. Some embodiments may additionally or alternatively include a Digital Signal Processor (DSP), which is a special purpose microprocessor having an architecture optimized for the operational requirements of the digital signal processing associated with the disclosed functionality of the present application. Similarly, various components or sub-components within each module may be implemented in software, hardware, or firmware. Connections between modules and/or components within modules may be provided using any of the connection methods and media known in the art, including, but not limited to, communications over the internet, wired, or wireless networks using appropriate protocols.

While this document contains many specifics, these should not be construed as limitations on the scope of the claimed invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this 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.

Only a few embodiments and examples are described and other embodiments, enhancements and variations can be made based on what is described and illustrated in this disclosure.