WO2023201545A1

WO2023201545A1 - Methods, devices and computer readable medium for communication

Info

Publication number: WO2023201545A1
Application number: PCT/CN2022/087760
Authority: WO
Inventors: Gang Wang
Original assignee: Nec Corporation
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2023-10-26

Abstract

Embodiments of the present disclosure relate to methods, devices and computer readable medium for communication. According to embodiments of the present disclosure, a terminal device, in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, transmits a measurement report for the height event. The report criterion comprises at least one of: a prohibit timer being not running; the number of times that a leaving condition applicable for the height event has been met being less than a threshold number for a first time period; or a determination that the measurement report is allowed to be reported.

Description

METHODS, DEVICES AND COMPUTER READABLE MEDIUM FOR COMMUNICATION

FIELD

Embodiments of the present disclosure generally relate to the field of communication, and in particular, to methods, devices and computer readable medium for communication.

BACKGROUND

With the development of Unmanned Aerial Vehicle (UAV) communication technology, there is a growing trend of interactions between a UAV device and an evolved NodeB (eNB) to ensure quality of service. For example, if a height of the UAV device is below that of the eNB, radio characteristic of the UAV device are more like a terrestrial terminal device, for example, multipath transmission and limited neighbor interference, and if the height the UAV device is above that of the eNB, radio characteristic of the UAV device are different from that of the terrestrial terminal device, for example, line of sight transmission and strong neighbor interference. Thus, there is a need for the eNB to track altitude change of the UAV device to adjust communication mode. As another example, as the UAV device may see more cells with similar signal strength than a terrestrial terminal device, the tracking area update may be triggered more frequently. However, frequent interactions between the UAV device and the eNB may cause high signaling overhead and interferences. In this case, among others open issues, how to avoid unnecessary signaling overhead and power consumption is still an open issue to be addressed.

SUMMARY

In general, example embodiments of the present disclosure relate to methods, devices and computer readable medium for communication.

In a first aspect, there is provided a method implemented by a terminal device. In the method, the terminal device, in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, transmits a measurement report for the height event. The report criterion comprises at least one of: a prohibit timer being not running; the number of times that a leaving condition applicable for the height event has been met being less than a threshold number for a first time period; or a determination that the measurement report is allowed to be reported.

In a second aspect, there is provided a method implemented by a terminal device. In the method, the terminal device determines a reference height. Then, in accordance with a determination that a condition applicable for a height measurement report is fulfilled, transmits the height measurement report. The condition comprises a difference between a height of the terminal device and the reference height being equal to or greater than a threshold height.

In a third aspect, there is provided a method implemented by an access network device. In the method, the access network device transmits a measurement configuration. Then, the access network device receives a measurement report for a height event. The measurement configuration comprises at least one of the following: a prohibit timer; a threshold number; a first time period; or a threshold height.

In a fourth aspect, there is provided a method implemented by a terminal device. In the method, the terminal device receives, from a core network device, extended tracking area information, the extended tracking area information comprising additional tracking area. Then the terminal device receives, from an access network device, an aerial height threshold. Further, in response to a height of the terminal device exceeds the aerial height threshold, the terminal device performs tracking area updating based on the extended tracking area information.

In a fifth aspect, there is provided a method implemented by an access network device. In the method, the access network device transmits, to a terminal device, an aerial height threshold. Then, the access network device determines aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information, the extended tracking area information comprising additional tracking area. Further, the access network device transmits, to a core network device, the aerial state information for the terminal device.

In a sixth aspect, there is provided a method implemented by a core network device. In the method, the core network device transmits, towards a terminal device, extended tracking area information, the extended tracking area information comprising additional tracking area. Then, the core network device receives, from an access network device, aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information. Further, the core network device pages the terminal device based on the extended tracking area information.

In a seventh aspect, there is provided a method implemented by a terminal device. In the method, the terminal device receives, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area. Then, the terminal device receives an aerial height threshold. Further, in response to a height of the terminal device exceeds the aerial height threshold, the terminal device performs RNA updating based on the extended RNA information.

In an eighth aspect, there is provided a method implemented by an access network device. In the method, the access network device transmits, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area. Further, the access network device transmits an aerial height threshold. Then, the access network device determines aerial state information for a terminal device, the aerial state information indicating whether a height of the terminal device exceeds the aerial height threshold. Then, in accordance with a determination that the height of the terminal device exceeds the aerial height threshold, the access network device pages the terminal device based on the extended RNA information.

In the ninth aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the terminal device to perform the method of any one of the first aspect, the second aspect, the fourth aspect and the seventh aspect.

In the tenth aspect, there is provided an access network device. The access network device comprises a processor and a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the access network device to perform the method of any one of the third aspect, the fifth aspect and the eighth aspect.

In the eleventh aspect, there is provided a core network device. The core network device comprises a processor and a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the core network device to perform the method of the sixth aspect.

In the twelfth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method of any one of the first aspect to the eighth aspect.

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

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:

FIG. 1 illustrates an example environment in which some embodiments of the present disclosure can be implemented;

FIG. 2A illustrates a signaling flow between the terminal device and the access network device for height measurement reporting according to some embodiments of the present disclosure;

FIG. 2B illustrates a schematic diagram for measurement reporting with a fluctuation restriction according to some embodiments of the present disclosure;

FIG. 3A illustrates a signaling flow between the terminal device and the access network device for height measurement reporting according to some other embodiments of the present disclosure;

FIG. 3B illustrates a schematic diagram for measurement reporting with a reference height restriction according to some embodiments of the present disclosure;

FIG. 3C illustrates a schematic diagram for periodic measurement reporting with a reference height restriction according to some embodiments of the present disclosure;

FIG. 4 illustrates a signaling flow among the terminal device, the access network device and the core network device for tracking area update according to some embodiments of the present disclosure;

FIG. 5 illustrates a signaling flow between the terminal device and the access network device for RNA update according to some embodiments of the present disclosure;

FIG. 6 illustrates a flowchart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a flowchart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of an example method of communication implemented at an access network device in accordance with some embodiments of the present disclosure;

FIG. 9 illustrates a flowchart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

FIG. 10 illustrates a flowchart of an example method of communication implemented at an access network device in accordance with some embodiments of the present disclosure;

FIG. 11 illustrates a flowchart of an example method of communication implemented at a core network device in accordance with some embodiments of the present disclosure;

FIG. 12 illustrates a flowchart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

FIG. 13 illustrates a flowchart of an example method of communication implemented at an access network device in accordance with some embodiments of the present disclosure; and

FIG. 14 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure.

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

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term ‘terminal device’ refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Small Data Transmission (SDT) , mobility, Multicast and Broadcast Services (MBS) , positioning, dynamic/flexible duplex in commercial networks, reduced capability (RedCap) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also incorporated one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device.

As used herein, the term “access network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , Network-controlled Repeaters, and the like.

As used herein, the term “core network device” refers to a device capable of communicating with the access network device and providing services to the terminal device in a core network. Examples of the core network device may include user plane functions (UPFs) , application servers, Mobile Switching Centers (MSCs) , MMEs, Operation and Management (O&M) nodes, Operation Support System (OSS) nodes, Self-Organization Network (SON) nodes, positioning nodes such as Enhanced Serving Mobile Location Centers (E-SMLCs) , Mobile Data Terminals (MDTs) , a Common Control Network Function (CCNF) , an Access and mobility Management Function (AMF) , a Session Management Function (SMF) , a Policy Control Function (PCF) and/or a Location Management Function LMF.

The terminal device or the network device may have artificial intelligence (AI) or machine learning (ML) capability. It generally includes one or more models which have been trained from numerous collected data for a specific function, and can be used to predict some information.

The terminal device or the network device may have Artificial intelligence (AI) or Machine learning capability. It generally includes a model which has been trained from numerous collected data for a specific function, and can be used to predict some information. The terminal or the network device may work on several frequency ranges, e.g. FR1 (410 MHz –7125 MHz) , FR2 (24.25 GHz to 71 GHz) , 71 GHz to 114 GHz, and frequency band larger than 100 GHz as well as Tera Hertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connections with the network devices under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The network device may have the function of network energy saving, Self-Organising Networks (SON) /Minimization of Drive Tests (MDT) . The terminal may have the function of power saving

The embodiments of the present disclosure may be performed in test equipment, e.g. signal generator, signal analyzer, spectrum analyzer, network analyzer, test terminal device, test network device, channel emulator.

The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

As used herein, the singular forms ‘a’ , ‘an’ and ‘the’ are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term ‘includes’ and its variants are to be read as open terms that mean ‘includes, but is not limited to. ’ The term ‘based on’ is to be read as ‘at least in part based on. ’ The term ‘one embodiment’ and ‘an embodiment’ are to be read as ‘at least one embodiment. ’ The term ‘another embodiment’ is to be read as ‘at least one other embodiment. ’ The terms ‘first, ’ ‘second, ’ and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as ‘best, ’ ‘lowest, ’ ‘highest, ’ ‘minimum, ’ ‘maximum, ’ or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

In the third generation partnership project (3GPP) meetings, there are some discussions about measurement reporting. For example, measurement reporting may be classified as periodical measurement reporting and event-triggered measurement reporting. An entering condition applicable for the existing measurement reporting triggered by an aerial UE height above a threshold may be specified as: Ms-Hys>Thresh+Offset and a leaving condition applicable for this existing measurement reporting may be specified as: Ms+Hys<Thresh+Offset, wherein Ms is the aerial UE height, not taking into account any offsets, Hys is the hysteresis parameter (that is Hysteresis as defined within ReportConfigEUTRA) for this event, Thresh is the reference threshold parameter for this event given in MeasConfig (i.e. heightThreshRef as defined within MeasConfig) and Offset is the offset value to heightThreshRef to obtain the absolute threshold for this event (i.e. h1-ThresholdOffset as defined within ReportConfigEUTRA) . Ms is expressed in meters and Thresh is expressed in the same unit as Ms. Likewise, an entering condition applicable for the existing measurement reporting triggered by an aerial UE height below a threshold may be specified as: Ms+Hys>Thresh+Offset and a leaving condition applicable for this existing measurement reporting may be specified as:Ms-Hys<Thresh+Offset.

In this case, if the entering condition applicable for a height event 1 is fulfilled during time to trigger (TTT) , the UE may start to perform measurement reporting to inform the network device of “Aerial UE height is above a threshold” ; if the entering condition applicable for a height event 2 is fulfilled during TTT, the UE may start to perform measurement reporting to inform the network device of “Aerial UE height is below a threshold” .. By this way, the eNB may track altitude change of the UE to adjust communication mode.

However, if the UE changes its flying height frequently, especially in the cases where the leaving condition of measurement reporting for a height event is fulfilled and then next measurement reporting for this height event is triggered again shortly after, it may cause continuous measurement reporting.

Besides, as stated above, as the UE has a relatively high flying altitude, it may see more cells with similar signal strength than a terrestrial terminal device, and thus the tracking area update may be triggered more frequently.

Such frequent information reporting may lead to large resource overhead and high power consumption at a UE. Thus, there is a need to reduce unnecessary signaling overhead. Besides, by now, there is no effective way to avoid unnecessary interactions between the UE and the eNB to further improve communication efficiency.

In an aspect, some embodiments of the present disclosure provide a scheme of height measurement reporting. With the scheme, a terminal device transmits to an access network device a measurement report for the height event, in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled. the report criterion comprises at least one of: a prohibit timer being not running; the number of times that a leaving condition applicable for the height event has been met being less than a threshold number for a first time period; or a determination that the measurement report is allowed to be reported.

In another aspect, some other embodiments of the present disclosure provide a scheme of height measurement reporting. With the scheme, a terminal device determines a reference height. Then, in accordance with a determination that a condition applicable for a height measurement report is fulfilled, the terminal device transmits to an access network terminal device, the height measurement report. The condition comprises a difference between a height of the terminal device and the reference height being equal to or greater than a threshold height.

In a further aspect, some embodiments of the present disclosure provide a scheme of tracking area update. With the scheme, a terminal device receives from a core network device extended tracking area information, the extended tracking area information comprising additional tracking area. Then, the terminal device receives from an access network device an aerial height threshold. Further, the terminal device performs tracking area updating based on the extended tracking area information, in response to a height of the terminal device being higher than the aerial height threshold. At the access network device, it determines aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information, the extended tracking area information comprising additional tracking area. Then the access network device transmits, to a core network device, the aerial state information for the terminal device. The core network device pages the terminal device based on the extended tracking area information.

In yet a further aspect, some embodiments of the present disclosure provide a scheme of RNA update. With the scheme, a terminal device receives from an access network device extended RNA information, the extended RNA information comprising additional notification area. Then, the terminal device receives from the access network device an aerial height threshold. Further, the terminal device performs RNA updating based on the extended RNA information, in response to a height of the terminal device being higher than the aerial height threshold. At the access network device, it determines aerial state information for the terminal device, the aerial state information indicating whether a height of the terminal device exceeds the aerial height threshold. Then, in accordance with a determination that the height of the terminal device exceeds the aerial height threshold, the access network device pages the terminal device based on the extended RNA information.

In this way, signaling overhead and power consumption may be reduced flexibly and efficiently by avoid unnecessary information interactions between the terminal device and the network device. As such, interferences caused by signaling transmission can also be reduced.

FIG. 1 illustrates an example environment 100 in which example embodiments of the present disclosure can be implemented.

The environment 100, which may be a part of a communication network, comprises a terminal device 110 and an access network device 120. The terminal device 120 may communicate with the network device 110. In the communication system 100, a link from the access network device 120 to a terminal device 110 is referred to as a downlink (DL) , while a link from a terminal device 110 to the access network device 120 is referred to as an uplink (UL) . In DL, the access network device 120 is a transmitting (TX) device (or a transmitter) and the terminal device 110 is a receiving (RX) device (or a receiver) . In UL, the terminal device 110 is a TX device (or a transmitter) and the access network device 120 is a RX device (or a receiver) .

The environment 100 further comprises a core network device 130. The core network device 130 may be connected to the access network device 120 directly or indirectly via one or more other devices or functions. In the environment 100, the core network device 130 is shown to be physically separate from the access network device 120, for example. As an example, the core network device 130 may be implemented by an AMF. In some embodiments, the core network device 130 may be physically integrated into the access network device 120 and, for example, implemented as a function or entity physically integrated into the access network device 120. In this case, the core network device 130 may communicate with the access network device 120 through internal wiring.

It is to be understood that the number of devices or functions is shown in the environment 100 only for the purpose of illustration, without suggesting any limitation to the scope of the present disclosure. The environment 200 may include any other suitable devices, elements or functions for providing communication. For example, there may be one or more intermediates between the access network device 120 and the core network device 130.

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

Embodiments of the present disclosure can be applied to any suitable scenarios. For example, embodiments of the present disclosure can be implemented at reduced capability NR devices. Alternatively, embodiments of the present disclosure can be implemented in one of the followings: NR multiple-input and multiple-output (MIMO) , NR sidelink enhancements, NR systems with frequency above 52.6GHz, an extending NR operation up to 71GHz, narrow band-Internet of Thing (NB-IOT) /enhanced Machine Type Communication (eMTC) over non-terrestrial networks (NTN) , NTN, UE power saving enhancements, NR coverage enhancement, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB) , NR Multicast and Broadcast Services, or enhancements on Multi-Radio Dual-Connectivity.

High-level interactions between the devices and functions in the environment 200 will be discussed below with reference to FIGS. 2A-5. Reference is first made to FIG. 2A.

FIG. 2A illustrates a signaling flow between the terminal device and the access network device for height measurement reporting according to some embodiments of the present disclosure. For purpose of discussion, the flowchart 200 will be described with reference to FIG. 1.

As shown in FIG. 2A, the access network device 120 transmits (205) a measurement configuration to the terminal device 110. For example, the measurement configuration may comprise one or more configuration parameters for measurement reporting, which will be discussed in details in the following. Accordingly, the terminal device 110 receives the measurement configuration from the access network device 120, and performs measurement reporting based on the measurement configuration.

Then, in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, the terminal device 110 transmits (210) to the access network device 120 a measurement report for the height event.

In some embodiments, especially where when a flying status of the terminal device 110 is unstable, it may benefit to consider an addition restriction that the fluctuation is smaller than a threshold. In this case, the report criterion may comprise the number of times that a leaving condition applicable for the height event has been fulfilled being less than a threshold number for a time period (also referred to as a first time period) . The terminal device 110 may determine to transmit to the access network device 120 the measurement report for the height event, if the number of times that the leaving condition applicable for the height event has been fulfilled is less than the threshold number for the first time period. Otherwise, if the number of times that the leaving condition applicable for the height event has been fulfilled exceeds the threshold number for the first time period, it may not transmit to the access network device 120 the measurement report for the height event anymore. For example, the at least one of the threshold number and the first time period may be predetermined in the standard specification. Alternatively or in addition, the at least one of the threshold number and the first time period may be configured by the access network device 120. In this case, the measurement configuration mentioned above may comprise at least one of the threshold number and the first time period. As another example, one of the threshold number and the first time period may be determined by the terminal device 110, and the other may be determined by the access network device 120 and signaled to the terminal device 110.

For example, an example implementation may be embodied as follows:

■ if the triggerType is set to event and if the eventId is set to eventH1 or eventH2 and if the entering condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled during timeToTrigger defined within the VarMeasConfig for this event, while the VarMeasReportList does not include a measurement reporting entry for this measId:

● if, during past timeForTriggerEvaluate, the number of times which the leaving condition applicable for this event is fulfilled for timeToTrigger, does not exceed threshold:

○ include a measurement reporting entry within the VarMeasReportList for this measId;

○ set the numberOfReportsSent defined within the VarMeasReportList for this measId to 0;

○ initiate the measurement reporting procedure.

FIG. 2B illustrates a schematic diagram for measurement reporting with a fluctuation restriction according to some embodiments of the present disclosure. In this case, the first time period may be set to T time and the threshold number may be set to 2. As shown in FIG. 2B, at the time points 222 and 224, the number of times that the leaving condition applicable for the height event H1 has been fulfilled for the past T time is 1, which is less than the threshold number, and thus measurement reporting for the height event H1 may be triggered. At the time point 226, the number of times that the leaving condition applicable for the height event H1 has been fulfilled for the past T time is 3, which is higher than the threshold number, and thus measurement reporting for the height event H1 may not be triggered.

In some embodiments, the report criterion may comprise a prohibit timer being not running. In this case, upon transmission of a previous measurement report for the height event, a prohibit timer may be run at both the terminal device 110 and the access network device 120. Then, any subsequent measurement report for the height event may not be transmitted when the prohibit timer is running. When the prohibit timer expires or stops, the subsequent measurement report for the height event may be transmitted. Upon running of the prohibit timer, the access network device 120 may tend to consider that the terminal device 110 keeps satisfying the entering condition applicable for the height event. While the prohibit timer is running, a measurement report triggered by a different height event may be transmitted and in this case, the prohibit timer is stopped at the terminal device 110. Upon reception of the measurement report for the different height event, the access network device 120 may stop the prohibit timer. The setting of prohibit timer may be determined in a variety of means.

For example, the setting of prohibit timer may be determined by the terminal device 110. In this case, the terminal device 110 may determine dwell time information. For example, the dwell time information can be determined according to the prediction of a flying path, or a predefined flying plan. The dwell information can be a time value with which the prohibit timer may be started. Then, the terminal device 110 transmits to the access network device 120 an indication for the dwell time information. For example, the dwell time information may be comprised in a previous measurement report for the height event. In this case, the terminal device 110 may start the prohibit timer, upon transmission of the previous measurement report for the height event, in which the dwell time information is comprised. That is, upon transmission of the dwell time information, the terminal device 110 start the prohibit timer according to the dwell time information. Upon reception of the dwell time, the access network device also start a prohibit timer according to the dwell time information. On this basis, the prohibit timer may be started at the terminal device 110 and the access network device 120 respectively. Considering the propagation delay, prohibit timer located at terminal device 110 and access network device 120 may not have exactly the same value. Alternatively or in addition, the dwell time information may be transmitted to the access network device 120 before, and stored at the terminal device 110. In this case, the terminal device 110 may start the prohibit timer based on the stored dwell time information upon transmission of a previous measurement report for the height event.

For example, an example implementation may be embodied as follows:

■ if the triggerType is set to event and if the eventId is set to eventH1 and if the entering condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled during timeToTrigger defined within the VarMeasConfig for this event, while the VarMeasReportList does not include a measurement reporting entry for this measId:

● If timer triggerH2 is running,

○ Stop timer triggerH2

● If timer triggerH1 is not running,

○ initiate the measurement reporting procedure;

…

◆ if the triggerType is set to event; and if eventId is set to eventH1:

■ set the heightUE to include the altitude of the UE;

■ set the dwell time

■ start timer triggerH1

Alternatively or in addition, the setting of prohibit timer may be determined by the access network device 120. In this case, the terminal device 110 may transmits to the access network device 120 information for assisting the access network device 120 in determination of the prohibit timer. For example, such assisting information may comprise dwell time information or a height variation of the terminal device 120 during a time period (also referred to as a second time period) . Then, the access network device 120 may determine the time configuration of the prohibit timer based on the assisting information. In this case, the measurement configuration transmitted from the access network device 120 to the terminal device 110 as mentioned above may comprise a configuration for the prohibit timer. For example, the prohibit timer may be configured in “measConfig” . Then, for example, the terminal device 110 may start the prohibit timer upon reception of the measurement configuration. As another example, the terminal device 110 may start the prohibit timer upon transmission of a previous measurement report for the height event. Accordingly, the access network device 120 may start the prohibit timer.

In this way, repetitive reporting can be avoided during a time period, thus signaling can be reduced to improve the interference to other UEs. Besides, the access network device 120 can get clearer knowledge of the height status of the terminal device 110. During the time period, the access network device 120 may consider the terminal device 110 is still satisfy the entering condition applicable for the height event, and outside the time period, the access network device 120 may consider that terminal device 110 keeps satisfying the entering condition applicable for the height event or keeps leaving height event but triggering no new height event.

In some embodiments, the report criterion may comprise a determination that the measurement report is allowed to be reported. In this case, for example, if the terminal device 110 determines that a previous measurement report is for a first height event, it may determine that the measurement report for a second height event different from the first height event is allowed to be reported. That is, after first transmission of a measurement report for the first height event, any subsequent measurement report for the first event will not be transmitted anymore, until a measurement report for the second height event is triggered.

For example, the terminal device 110 may use a flag, such as “triggerStatus” , to indicate reporting status of the height event. For example, the “triggerStatus” may be set to the first value if measurement reporting for the first height event is initiated, and the “triggerStatus” may be set to the second value if measurement reporting for the second height event is initiated. In some examples, the terminal device 110 may initiate the measurement reporting procedure for the first height event, and then set the “triggerStatus” to the first value. Then, if a subsequent height event is triggered by the first height event, the “triggerStatus” indicates that this subsequent triggered event is the same event as the latest event which has initiated the measurement report, thus the subsequent measurement reporting procedure for the first height event may not be initiated. Otherwise, if the subsequent height event is triggered by the second height event, the “triggerStatus” indicate that this subsequent triggered event is a different event from the latest event which has initiated the measurement report, thus the subsequent measurement reporting procedure for the second height event may be initiated. That is, the first event can only trigger measurement report when the “triggerStatus” has been set to the second value, and the second event can only trigger measurement report when the “triggerStatus” has been set to the first value. In some embodiments, for the first time a height event is triggered, the measurement reporting will always be initiated. In some embodiments, the initiate value of the “triggerStatus” is set according to the height of terminal device 110 when terminal device 110 enters RRC_CONNECTED state. For example, if the height of the terminal device 110 has been reported to the access network device 120 during a random access procedure. Upon received the measurement configuration of height event, the “triggerStatus” can be set based on the reported height. For example, set “triggerStatus” to the first value if the reported height is larger than the height threshold for the first height event. Set “triggerStatus” to the second value if the reported height is lower than the height threshold for the second height event. Otherwise, the value of “triggerStatus” may keep absent and the first trigger of height event will always initiate measurement report.

For example, an example implementation may be embodied as follows:

■ If VarMeasConfig includes both eventH1 and eventH2

● if the triggerType is set to event and if the eventId is set to eventH1 while triggerStatus is set to 1 and if the entering condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled during timeToTrigger defined within the VarMeasConfig for this event; or

● if the triggerType is set to event and if the eventId is set to eventH2 while triggerStatus is set to 0 and if the entering condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled during timeToTrigger defined within the VarMeasConfig for this event:

○ initiate the measurement reporting procedure, as specified in 5.5.5;

○ if the eventId is set to eventH1:

■ set triggerStatus to 0;

○ if the eventId is set to eventH2:

■ set triggerStatus to 1.

In some embodiments, except adding a report criterion to reduce unnecessary measurement report, the terminal device 110 may scale TTT by vertical mobility levels when the flying status is unstable. For example, the access network device 120 may configure correspondences between a plurality of TTT and vertical mobility levels of the terminal device 110 and indicate the correspondences to the terminal device 110. As an example, the access network device 120 may determine such correspondences based on height change in a past time period or vertical speed measured by the terminal device 110. For example, the access network device 120 may determine two mobility level thresholds (also referred to as a first mobility level threshold and a second mobility level threshold) to evaluate the vertical mobility levels of the terminal device 110 as three classes corresponding to three deferent TTT respectively, such as a high TTT, a medium TTT and a low TTT. In this case, the high TTT may be used if the vertical mobility level of the terminal device 110 is equal or higher than the first mobility level threshold. The medium TTT may be used if the vertical mobility level of the terminal device 110 is between the first mobility level threshold and the second mobility level threshold. The low TTT may be used if the vertical mobility level of the terminal device 110 is equal or lower than the second mobility level threshold. In this way, if the height of the terminal device 110 changes rapidly, longer TTT may need to be satisfied for height event triggering, which may further reduce signaling overhead.

FIG. 3A illustrates a signaling flow between the terminal device and the access network device for height measurement reporting according to some other embodiments of the present disclosure. For purpose of discussion, the flowchart 300 will be described with reference to FIG. 1.

As shown in FIG. 3A, the access network device 120 transmits (305) a measurement configuration to the terminal device 110. For example, the measurement configuration may comprise one or more configuration parameters for measurement reporting, which will be discussed in details in the following. Accordingly, the terminal device 110 receives the measurement configuration from the access network device 120, and performs measurement reporting based on the measurement configuration.

Then, the terminal device 110 determines (310) a reference height. For example, the measurement configuration mentioned above may comprise initial reference height information, and then, on this basis, the terminal device 110 may initialize the reference height. As another example, the terminal device 110 may initialize the reference height based on a height of the terminal device 110 when receiving the measurement configuration. Alternatively or in addition, the terminal device 110 may initialize the reference height based on a height of the terminal device when entering a radio resource control connected state.

After initialization of the reference height, the reference height may be updated in a variety of means. For example, the reference height may be updated as a latest height of the terminal device 110 transmitted by the height measurement report. As another example, the measurement configuration may comprise a regular interval for updating the reference height, and in this case, the reference height may be updated as a latest height of the terminal device with the regular interval. As yet an example, the measurement configuration may comprises a time period (also referred to as a third time period) for updating the reference height, and in this case, the reference height may be updated as a latest height of the terminal device, if the terminal device 110 determines that the condition applicable for the height measurement report is not fulfilled during the third time period. That is, no height measurement report for this event is triggered during the past third time period. For example, the third time period may be configured by the access network device 120 and signaled to the terminal device 110 in the measurement configuration mentioned above.

As shown in FIG. 3A, the terminal device 110 transmits (315) to the access network device 120 a height measurement report, if it determines that a condition applicable for a height measurement report is fulfilled. The condition comprises a difference between a height of the terminal device 110 and the reference height described as above being equal to or greater than a threshold height. For example, the threshold height may be predefined by the standard specifications. As another example, the threshold height may be determined by the access network device 120 and signaled to the terminal device 110, and in this case, the measurement configuration mentioned above may indicate the threshold height.

For example, in this case, the entering condition applicable for the measurement reporting triggered by the height of the terminal device 110 above a threshold may be specified as: Ms-Href-Hys>Thresh and a leaving condition applicable for this measurement reporting may be specified as: Ms-Href+Hys<Thresh, wherein the Href is the reference height, and the Thresh is the reference threshold parameter for this event given in MeasConfig (i.e. heightThreshRef as defined within MeasConfig) and need to be updated upon triggering of this event.

For example, an example implementation may be embodied as follows:

The definition of Event H3 (The change of the Aerial UE height is above a threshold) :

The UE shall:

◆ consider the entering condition applicable for this event to be satisfied when condition H1-1, as specified below, is fulfilled;

◆ consider the leaving condition applicable for this event to be satisfied when condition H1-2, as specified below, is fulfilled;

Inequality H1-1 (Entering condition)

Ms-Href-Hys>Thresh

Inequality H1-2 (Leaving condition)

Ms-Href+Hys<Thresh

where the variables in the formula are defined as follows:

Ms is the Aerial UE height, not taking into account any offsets.

Hys is the hysteresis parameter (i.e. h1-Hysteresis as defined within ReportConfigEUTRA) for this event.

Thresh is the reference threshold parameter for this event given in MeasConfig (i.e. heightThreshRef as defined within MeasConfig) . And need to be updated upon triggering of this event.

Ms is expressed in meters.

Thresh is expressed in the same unit as Ms.

Measurement report triggering procedures:

■ if the triggerType is set to event and if the eventId is set to eventH3 and if the entering condition applicable for this event, i.e. the event corresponding with the eventId of the corresponding reportConfig within VarMeasConfig, is fulfilled during timeToTrigger defined within the VarMeasConfig for this event, while the VarMeasReportList does not include a measurement reporting entry for this measId:

● include a measurement reporting entry within the VarMeasReportList for this measId;

● set the numberOfReportsSent defined within the VarMeasReportList for this measId to 0;

● update the threshold for this event with the altitude of the UE;

● initiate the measurement reporting procedure, as specified in 5.5.5.

FIG. 3B illustrates a schematic diagram for measurement reporting with a reference height restriction according to some embodiments of the present disclosure. In this case, the threshold height may be set to the threshold 330. As shown in FIG. 3B, the initial reference height is initialized as the height 331. At the time point 332, the terminal device 110 may determine that the difference between the height 333 of the terminal device 110 and the reference height 331 is equal to or higher than the threshold 330. Then the height measurement reporting may be triggered and the reference height is updated as the height 333. At the time point 334, the terminal device 110 may determine that the difference between the height 335 of the terminal device 110 and the reference height 333 is equal to or higher than the threshold 330. Then the subsequent height measurement reporting may be triggered and the reference height is updated as the height 335. At the time point 336, the terminal device 110 may determine that the difference between the height 337 of the terminal device 110 and the reference height 335 is equal to or higher than the threshold 330. Then the subsequent height measurement reporting may be triggered and the reference height is updated as the height 337.

In some embodiments, the condition may further be based on a periodic timer. In this case, upon expiration of the periodic timer, the terminal device 110 may transmits to the access network device 120 the height measurement report if it determines that the difference between the height of the terminal device and the reference height is equal to or greater than the threshold height. In consequence, if there's absent measurement report after triggering of measurement reporting, the access network device 120 may consider the height fluctuating of the terminal device 110 is in a small range without leaving last reported event, and if the subsequent reporting terminates before the number of measurement report sent reaching the pre-defined report amount, the access network device 120 may consider that the terminal device 110 leaves the event.

FIG. 3C illustrates a schematic diagram for periodic measurement reporting with a reference height restriction according to some embodiments of the present disclosure. In this case, the threshold height may be set to the threshold 340. As shown in FIG. 3C, the initial reference height is initialized as the height 341. At the time point 342, the terminal device 110 may determine that the difference between the height 343 of the terminal device 110 and the reference height 341 is equal to or higher than the threshold 340. Then the height measurement reporting may be triggered and the reference height is updated as the height 343. At the time point 344, the terminal device 110 may determine that the difference between the height 345 of the terminal device 110 and the reference height 343 is equal to or higher than the threshold 340. Then the subsequent height measurement reporting may be triggered and the reference height is updated as the height 345. At the time point 346, the terminal device 110 may determine that the difference between the height 347 of the terminal device 110 and the reference height 345 is lower than the threshold 340. Then the subsequent height measurement report may not be triggered and in this case, the reference height may not be updated. At the time point 348, the terminal device 110 may determine that the difference between the height 349 of the terminal device 110 and the reference height 345 is equal to or higher than the threshold 340. Then the subsequent height measurement reporting may be triggered and the reference height is updated as the height 349.

In this way, measurement reporting is only performed when considerable movement has been made, which can improve signaling overhead.

FIG. 4 illustrates a signaling flow among the terminal device, the access network device and the core network device for tracking area update according to some embodiments of the present disclosure. For purpose of discussion, the flowchart 400 will be described with reference to FIG. 1.

In some embodiments, the core network device 130 may assign tracking area information (TAI) indicating a registration area the terminal device 110 is registered to in the REGISTRATION ACCEPT message.

In some embodiments, during registration, the terminal device 110 may be identified as an aerial UE. In this case, as the aerial UE may see more cells with similar signal strength than a terrestrial terminal device, it may cause frequent tracking area update to perform tracking area updating based on the above original TAI.

Then, as shown in the FIG. 4, if the terminal device 110 is be identified as an aerial UE, the core network device 130 transmits (405) , towards the terminal device 110, extended TAI. The extended TAI comprises additional tracking area, which may be a delta configuration of the original TAI. For example, if the extended TAI is used, the terminal device 110 may determine that there is no need to perform tracking area updating if the cell to which the terminal device 110 is connected belongs to the tracking area determined based on the extended TAI.

Further, the access network device 120 may transmits (410) an aerial height threshold to the terminal device 110. For example, the aerial height threshold may be used to be compared with a height of the terminal device 110 for determination of the performing of tracking area updating.

The access network device 120 determines (415) aerial state information for the terminal device 110. The aerial state information indicates use of the extended TAI. In some embodiments, the access network device 120 may transmit a UECapabilityEnquiry message to the terminal device 110 and then receive a UECapabilityInformation message from the terminal device 110. Then, the access network device 120 may determine the aerial state information for the terminal device 110 based on the UECapabilityInformation. Alternatively or in addition, the access network device 120 may determine the aerial state information for the terminal device 110 based on RRC_connected measurement report or location report or flying path report. Then, the access network device 120 transmits (420) , to the core network device 130, the aerial state information for the terminal device 110. For example, the aerial state information for the terminal device 110 may be transmitted to the core network device 130 in a UE Context Release Request message.

Then, according to the aerial state information for the terminal device 110, the core network device 130 pages (425) the terminal device 110 based on the extended TAI.

The terminal device 110 performs (430) tracking area updating based on the extended TAI, if it determines that the height of the terminal device 110 exceeds the aerial height threshold. Otherwise, the terminal device 110 may perform tracking area updating based on the original TAI, if it determines that the height of the terminal device 110 doses not exceed the aerial height threshold.

In this way, frequently tracking area updating can be avoided. Signaling overhead can be reduced.

FIG. 5 illustrates a signaling flow between the terminal device and the access network device for RNA update according to some embodiments of the present disclosure. For purpose of discussion, the flowchart 500 will be described with reference to FIG. 1.

In some embodiments, the access network device 120 may assign RNA information indicating a registration area when suspending the terminal device 110.

In some embodiments, during registration, the terminal device 110 may be identified as an aerial UE. In this case, as the aerial UE may see more cells with similar signal strength than a terrestrial terminal device, it may cause frequent RNA update to perform tracking area updating based on the above original RNA information.

Then, as shown in the FIG. 5, if the terminal device 110 is be identified as an aerial UE, the access network device 120 transmits (505) to the terminal device 110 extended RNA information. The extended RNA information comprises additional notification area, which is a delta configuration of the original RNA information. An example, the extended RNA information may be configured in a “ranExtendedNotificationAreaInfo” field comprised in a RRC Release message. For example, if the extended RNA information is used, the terminal device 110 may determine that there is no need to perform RNA updating if the cell to which the terminal device 110 is connected belongs to the tracking area determined based on the extended RNA information.

Further, the access network device 120 transmits (510) an aerial height threshold to the terminal device 110. For example, the aerial height threshold may be used to be compared with a height of the terminal device 110 for determination of the performing of tracking area updating.

The access network device 120 determines (515) aerial state information for the terminal device 110. The aerial state information indicates whether the height of the terminal device 110 exceeds the aerial height threshold. In some embodiments, the access network device 120 may transmit a UECapabilityEnquiry message to the terminal device 110 and then receive a UECapabilityInformation message from the terminal device 110. Then, the access network device 120 may determine the aerial state information for the terminal device 110 based on the UECapabilityInformation. Alternatively or in addition, the access network device 120 may determine the aerial state information for the terminal device 110 based on RRC_connected measurement report or location report or flying path report.

In some embodiments, if the access network device 120 is the last serving access network device, it may forward the aerial state information to other access network devices. And the other access network devices may store the aerial state information and use it to page the terminal device 110, if it determines that the height of the terminal device 110 exceeds the aerial height threshold.

Otherwise, if the access network device 120 is the current serving access network device, the access network device 120 pages (520) the terminal device 110 based on the extended RNA information, if it determines that the height of the terminal device 110 exceeds the aerial height threshold.

The terminal device 110 performs (525) RNA updating based on the extended RNA information if it determines that the height of the terminal device 110 exceeds the aerial height threshold. Otherwise, the terminal device 110 may perform RNA updating based on the original RNA information, if it determines that the height of the terminal device 110 doses not exceed the aerial height threshold.

In this way, frequently RNA updating can be avoided. Signaling overhead can be reduced.

FIG. 6 illustrates a flowchart of an example method 600 of communication implemented at a terminal device in accordance with some embodiments of the present disclosure. The method 600 can be implemented at the terminal device 110 shown in FIG. 1. For the purpose of discussion, the method 600 will be described with reference to FIG. 1. It is to be understood that the method 600 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 610, the terminal device 110, in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, transmits a measurement report for the height event. The report criterion comprises at least one of: a prohibit timer being not running; the number of times that a leaving condition applicable for the height event has been fulfilled being less than a threshold number for a first time period; or a determination that the measurement report is allowed to be reported.

In some embodiments where the report criterion comprises the prohibit timer being not running, the terminal device 110 may transmit an indication for dwell time information, and start the prohibit timer with a time value determined based on the dwell time information.

In some embodiments where the report criterion comprises the prohibit timer being not running, the terminal device 110 may receive a measurement configuration for the prohibit timer; and start the prohibit timer upon reception of the measurement configuration or upon transmission of a previous measurement report for the height event.

In some embodiments, the terminal device 110 may transmit at least one of the following to assist a network device in determination of the prohibit timer: dwell time information; or a height variation of the terminal device during a second time period.

In some embodiments where the report criterion comprises the number of times that the leaving condition applicable for the height event has been met being less than the threshold number for the first time period, the terminal device 110 may receive a measurement configuration indicating at least one of: the threshold number and the first time period.

In some embodiments, the terminal device 110 may, in accordance with a determination that a previous measurement report is for a first height event, determine that the measurement report for a second height event different from the first height event is allowed to be reported.

Those skilled in the art can understand that all operations and features as described above with reference to FIGS. 2A-2B are likewise applicable to the method 600 and have similar effects.

FIG. 7 illustrates a flowchart of an example method 700 of communication implemented at a terminal device in accordance with some embodiments of the present disclosure. The method 700 can be implemented at the terminal device 110 shown in FIG. 1. For the purpose of discussion, the method 700 will be described with reference to FIG. 1. It is to be understood that the method 700 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 710, the terminal device 110 determines a reference height. At block 720, the terminal device 110, in accordance with a determination that a condition applicable for a height measurement report is fulfilled, transmits the height measurement report. The condition comprises a difference between a height of the terminal device and the reference height being equal to or greater than a threshold height.

In some embodiments, the terminal device 110 may receive a measurement configuration indicating the threshold height.

In some embodiments, the terminal device 110 may update the reference height as a latest height of the terminal device transmitted by the height measurement report.

In some embodiments, the measurement configuration may further comprise a regular interval for updating the reference height, and the terminal device 110 may update the reference height as a latest height of the terminal device with the regular interval.

In some embodiments, the measurement configuration may further comprise a second time period for updating the reference height, and the terminal device 110 may update the reference height as a latest height of the terminal device, in accordance with a determination that the condition applicable for the height measurement report is not fulfilled during the third time period.

In some embodiments, the condition may be further based on a periodic timer, and the terminal device 110 may upon expiration of the periodic timer, transmit the height measurement report, in accordance with a determination that the difference between the height of the terminal device and the reference height is equal to or greater than the threshold height.

In some embodiments, the terminal device 110 may initialize the reference height based on one of: initial reference height information comprised in the measurement configuration; a height of the terminal device when receiving the measurement configuration; or a height of the terminal device when entering a radio resource control connected state.

Those skilled in the art can understand that all operations and features as described above with reference to FIGS. 3A-3C are likewise applicable to the method 700 and have similar effects.

. FIG. 8 illustrates a flowchart of an example method 800 of communication implemented at an access network device in accordance with some embodiments of the present disclosure. The method 800 can be implemented at the access network device 120 shown in FIG. 1. For the purpose of discussion, the method 800 will be described with reference to FIG. 1. It is to be understood that the method 800 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 810, the access network device 120 transmits a measurement configuration. At block 820, the access network device 120 receives a measurement report for a height event. The measurement configuration comprises at least one of the following: a prohibit timer; a threshold number; a first time period; or a threshold height.

In some embodiments where the measurement configuration comprises the prohibit timer, the access network device 120 may receive at least one of the following to assist a network device in determination of the prohibit timer: dwell time information; or a height variation of a terminal device during a second time period.

In some embodiments where the measurement configuration comprises the threshold height, the measurement configuration may further comprise at least one of: a regular interval; a third time period; or an initial reference height.

Those skilled in the art can understand that all operations and features as described above with reference to FIGS. 2A-3C are likewise applicable to the method 800 and have similar effects.

. FIG. 9 illustrates a flowchart of an example method 900 of communication implemented at a terminal device in accordance with some embodiments of the present disclosure. The method 900 can be implemented at the terminal device 110 shown in FIG. 1. For the purpose of discussion, the method 900 will be described with reference to FIG. 1. It is to be understood that the method 900 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 910, the terminal device 110 receives from the core network device 130, extended tracking area information, the extended tracking area information comprising additional tracking area. At block 920, the terminal device 110 receives from the access network device 120 an aerial height threshold. At block 930, the terminal device 110, in response to a height of the terminal device exceeds the aerial height threshold, perform tracking area updating based on the extended tracking area information.

. Those skilled in the art can understand that all operations and features as described above with reference to FIG. 4 are likewise applicable to the method 900 and have similar effects.

FIG. 10 illustrates a flowchart of an example method 1000 of communication implemented at an access network device in accordance with some embodiments of the present disclosure. The method 1000 can be implemented at the access network device 120 shown in FIG. 1. For the purpose of discussion, the method 1000 will be described with reference to FIG. 1. It is to be understood that the method 1000 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 1010, the access network device 120 transmits, to the terminal device 110, an aerial height threshold. At block 1020, the access network device 120 determines aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information, the extended tracking area information comprising additional tracking area. At block 1030, the access network device 120 transmits, to the core network device 130, the aerial state information for the terminal device 110.

. Those skilled in the art can understand that all operations and features as described above with reference to FIG. 4 are likewise applicable to the method 1000 and have similar effects.

FIG. 11 illustrates a flowchart of an example method 1100 of communication implemented at an access network device in accordance with some embodiments of the present disclosure. The method 1100 can be implemented at the core network device 130 shown in FIG. 1. For the purpose of discussion, the method 1100 will be described with reference to FIG. 1. It is to be understood that the method 1100 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 1110, the core network device 130 transmits, towards the terminal device 110, extended tracking area information, the extended tracking area information comprising additional tracking area. At block 1120, the core network device 130 receives, from the access network device 120, aerial state information for the terminal device 110, the aerial state information indicating use of the extended tracking area information. At block 1130, the core network device 130 pages the terminal device 110 based on the extended tracking area information.

Those skilled in the art can understand that all operations and features as described above with reference to FIG. 4 are likewise applicable to the method 1100 and have similar effects.

FIG. 12 illustrates a flowchart of an example method 1200 of communication implemented at a terminal device in accordance with some embodiments of the present disclosure. The method 1200 can be implemented at the terminal device 110 shown in FIG. 1. For the purpose of discussion, the method 1200 will be described with reference to FIG. 1. It is to be understood that the method 1200 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 1210, the terminal device 110 receives extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area. At block 1220, the terminal device 110 receives an aerial height threshold. At block 1230, the terminal device 110, in response to a height of the terminal device exceeds the aerial height threshold, performs RNA updating based on the extended RNA information.

. Those skilled in the art can understand that all operations and features as described above with reference to FIG. 5 are likewise applicable to the method 1200 and have similar effects.

FIG. 13 illustrates a flowchart of an example method 1300 of communication implemented at an access network device in accordance with some embodiments of the present disclosure. The method 1300 can be implemented at the access network device 120 shown in FIG. 1. For the purpose of discussion, the method 1300 will be described with reference to FIG. 1. It is to be understood that the method 1300 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At block 1310, the access network device 120 transmits extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area. At block 1320, the access network device 120 transmits an aerial height threshold. At block 1330, the access network device 120 determines aerial state information for a terminal device, the aerial state information indicating whether a height of the terminal device exceeds the aerial height threshold. At block 1340, the access network device 120, in accordance with a determination that the height of the terminal device exceeds the aerial height threshold, pages the terminal device based on the extended RNA information.

. Those skilled in the art can understand that all operations and features as described above with reference to FIG. 5 are likewise applicable to the method 1300 and have similar effects.

FIG. 14 is a simplified block diagram of a device 1400 that is suitable for implementing some embodiments of the present disclosure. The device 1400 can be considered as a further example embodiment of the terminal device 110, or the access network device 120 or the core network device 130 as shown in FIG. 1. Accordingly, the device 1400 can be implemented at or as at least a part of the terminal device 110 or the access network device 120 or the core network device 130 as shown in FIG. 1.

As shown, the device 1400 includes a processor 1410, a memory 1420 coupled to the processor 1410, a suitable transmitter (TX) and receiver (RX) 1440 coupled to the processor 1410, and a communication interface coupled to the TX/RX 1440. The memory 1420 stores at least a part of a program 1430. The TX/RX 1440 is for bidirectional communications. The TX/RX 1440 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between gNBs or eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the gNB or eNB, Un interface for communication between the gNB or eNB and a relay node (RN) , or Uu interface for communication between the gNB or eNB and a terminal device.

The program 1430 is assumed to include program instructions that, when executed by the associated processor 1410, enable the device 1400 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIGS. 1-13. The embodiments herein may be implemented by computer software executable by the processor 1410 of the device 1400, or by hardware, or by a combination of software and hardware. The processor 1410 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1410 and memory 1420 may form processing means 1450 adapted to implement various embodiments of the present disclosure.

The memory 1420 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 1420 is shown in the device 1400, there may be several physically distinct memory modules in the device 1400. The processor 1410 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1400 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

In some embodiments, a terminal device comprises circuitry configured to perform

method

600, 700, 900 and/or 1200.

In some embodiments, an access network device comprises circuitry configured to perform

method

800, 1000 and/or 1300.

In some embodiments, a core network device comprises circuitry configured to perform method 1100.

The components included in the apparatuses and/or devices of the present disclosure may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In one embodiment, one or more units may be implemented using software and/or firmware, for example, machine-executable instructions stored on the storage medium. In addition to or instead of machine-executable instructions, parts or all of the units in the apparatuses and/or devices may be implemented, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs) , Application-specific Integrated Circuits (ASICs) , Application-specific Standard Products (ASSPs) , System-on-a-chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , and the like.

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

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to any of FIGS. 1 to 13. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

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

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

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

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

Various example embodiments of the techniques have been described. In addition to or as an alternative to the above, the following examples are described. The features described in any of the following examples may be utilized with any of the other examples described herein.

In some aspects, a method comprises: in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, transmitting, at a terminal device, a measurement report for the height event, wherein the report criterion comprises at least one of: a prohibit timer being not running; the number of times that a leaving condition applicable for the height event has been fulfilled being less than a threshold number for a first time period; or a determination that the measurement report is allowed to be reported.

In some embodiments, the report criterion comprises the prohibit timer being not running, and the method further comprises: transmitting, at the terminal device, an indication for dwell time information, and starting, at the terminal device, the prohibit timer with a time value determined based on the dwell time information.

In some embodiments, the report criterion comprises the prohibit timer being not running, and the method further comprises: receiving, at the terminal device, a measurement configuration for the prohibit timer; and starting, at the terminal device, the prohibit timer upon reception of the measurement configuration or upon transmission of a previous measurement report for the height event.

In some embodiments, the method further comprises: transmitting, at the terminal device, at least one of the following to assist a network device in determination of the prohibit timer: dwell time information; or a height variation of the terminal device during a second time period.

In some embodiments, the report criterion comprises the number of times that the leaving condition applicable for the height event has been fulfilled being less than the threshold number for the first time period, and the method further comprises: receiving, at the terminal device, a measurement configuration indicating at least one of: the threshold number and the first time period.

In some embodiments, the determination that the measurement report is allowed to be reported comprises: in accordance with a determination that a previous measurement report is for a first height event, determining that the measurement report for a second height event different from the first height event is allowed to be reported.

In some aspects, a method comprises: determining, at a terminal device, a reference height; and in accordance with a determination that a condition applicable for a height measurement report is fulfilled, transmitting, at the terminal device, the height measurement report, wherein the condition comprises a difference between a height of the terminal device and the reference height being equal to or greater than a threshold height.

In some embodiments, the method further comprising: receiving, at the terminal device, a measurement configuration indicating the threshold height.

In some embodiments, determining the reference height comprises: updating the reference height as a latest height of the terminal device transmitted by the height measurement report.

In some embodiments, the measurement configuration further comprises a regular interval for updating the reference height, and determining the reference height comprises: updating the reference height as a latest height of the terminal device with the regular interval.

In some embodiments, the measurement configuration further comprises a second time period for updating the reference height, and determining the reference height comprises: updating the reference height as a latest height of the terminal device, in accordance with a determination that the condition applicable for the height measurement report is not fulfilled during the second time period.

In some embodiments, the condition is further based on a periodic timer, and transmitting the height measurement report comprises: upon expiration of the periodic timer, in accordance with a determination that the difference between the height of the terminal device and the reference height is equal to or greater than the threshold height, transmitting the height measurement report.

In some embodiments, determining the reference height comprises: initializing, at the terminal device, the reference height based on one of: initial reference height information comprised in the measurement configuration; a height of the terminal device when receiving the measurement configuration; or a height of the terminal device when entering a radio resource control connected state.

In some aspects, a method comprises: transmitting, at an access network device, a measurement configuration; and receiving, at the access network device, a measurement report for a height event, wherein the measurement configuration comprises at least one of the following: a prohibit timer; a threshold number; a first time period; or a threshold height.

In some embodiments, the measurement configuration comprises the prohibit timer, and the further comprises: receiving, at the access network device, at least one of the following to assist a network device in determination of the prohibit timer: dwell time information; or a height variation of a terminal device during a second time period.

In some embodiments, the measurement configuration comprises the threshold height, and the measurement configuration further comprises at least one of: a regular interval; a third time period; or an initial reference height.

In some aspects, a method comprises: receiving, at a terminal device, from a core network device, extended tracking area information, the extended tracking area information comprising additional tracking area; receiving, at the terminal device, from an access network device, an aerial height threshold; and in response to a height of the terminal device exceeds the aerial height threshold, performing, at the terminal device, tracking area updating based on the extended tracking area information.

In some aspects, a method comprises: transmitting, at an access network device, to a terminal device, an aerial height threshold; determining, at the access network device, aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information, the extended tracking area information comprising additional tracking area; and transmitting, at the access network device, to a core network device, the aerial state information for the terminal device.

In some aspects, a method comprises: transmitting, at a core network device, towards a terminal device, extended tracking area information, the extended tracking area information comprising additional tracking area; receiving, at the core network device, from an access network device, aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information; and paging, at the core network device, the terminal device based on the extended tracking area information.

In some aspects, a method comprises: receiving, at a terminal device, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area; receiving, at the terminal device, an aerial height threshold; and in response to a height of the terminal device exceeds the aerial height threshold, performing, at the terminal device, RNA updating based on the extended RNA information.

In some aspects, a method comprises: transmitting, at an access network device, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising additional notification area; transmitting, at the access network device, an aerial height threshold; determining, at the access network device, aerial state information for a terminal device, the aerial state information indicating whether a height of the terminal device exceeds the aerial height threshold; and in accordance with a determination that the height of the terminal device exceeds the aerial height threshold, paging, at the access network device, the terminal device based on the extended RNA information.

Claims

A method of communication, comprising:

in response to an entering condition applicable for a height event being fulfilled and a report criterion being fulfilled, transmitting, at a terminal device, a measurement report for the height event,

wherein the report criterion comprises at least one of:

a prohibit timer being not running;

the number of times that a leaving condition applicable for the height event has been met being less than a threshold number for a first time period; or

a determination that the measurement report is allowed to be reported.
The method of claim 1, wherein the report criterion comprises the prohibit timer being not running, and the method further comprising:

transmitting, at the terminal device, an indication for dwell time information, and

starting, at the terminal device, the prohibit timer with a time value determined based on the dwell time information.
The method of claim 1, wherein the report criterion comprises the prohibit timer being not running, and the method further comprising:

receiving, at the terminal device, a measurement configuration for the prohibit timer; and

starting, at the terminal device, the prohibit timer upon reception of the measurement configuration or upon transmission of a previous measurement report for the height event.
The method of claim 3, further comprising:

transmitting, at the terminal device, at least one of the following to assist a network device in determination of the prohibit timer:

dwell time information; or

a height variation of the terminal device during a second time period.
The method of claim 1, wherein the report criterion comprises the number of times that the leaving condition applicable for the height event has been fulfilled being less than the threshold number for the first time period, and the method further comprising:

receiving, at the terminal device, a measurement configuration indicating at least one of: the threshold number and the first time period.
The method of claim 1, wherein the determination that the measurement report is allowed to be reported comprises:

in accordance with a determination that a previous measurement report is for a first height event, determining that the measurement report for a second height event different from the first height event is allowed to be reported.
A method of communication, comprising:

determining, at a terminal device, a reference height; and

in accordance with a determination that a condition applicable for a height measurement report is fulfilled, transmitting, at the terminal device, the height measurement report,

wherein the condition comprises a difference between a height of the terminal device and the reference height being equal to or greater than a threshold height.
The method of claim 7, further comprising:

receiving, at the terminal device, a measurement configuration indicating the threshold height.
The method of claim 7 or 8, wherein determining the reference height comprises:

updating the reference height as a latest height of the terminal device transmitted by the height measurement report.
The method of claim 8, wherein the measurement configuration further comprises a regular interval for updating the reference height, and wherein determining the reference height comprises:

updating the reference height as a latest height of the terminal device with the regular interval.
The method of claim 8, wherein the measurement configuration further comprises a second time period for updating the reference height, and wherein determining the reference height comprises:

updating the reference height as a latest height of the terminal device, in accordance with a determination that the condition applicable for the height measurement report is not fulfilled during the second time period.
The method of claim 7, wherein the condition is further based on a periodic timer, and wherein transmitting the height measurement report comprises:

upon expiration of the periodic timer, in accordance with a determination that the difference between the height of the terminal device and the reference height is equal to or greater than the threshold height, transmitting the height measurement report.
The method of any of claims 8-12, wherein determining the reference height comprises:

initializing, at the terminal device, the reference height based on one of:

initial reference height information comprised in the measurement configuration;

a height of the terminal device when receiving the measurement configuration; or

a height of the terminal device when entering a radio resource control connected state.
A method of communication, comprising:

transmitting, at an access network device, a measurement configuration; and

receiving, at the access network device, a measurement report for a height event,

wherein the measurement configuration comprises at least one of the following:

a prohibit timer;

a threshold number;

a first time period; or

a threshold height.
The method of claim 14, wherein the measurement configuration comprises the prohibit timer, and the further comprising:

receiving, at the access network device, at least one of the following to assist a network device in determination of the prohibit timer:

dwell time information; or

a height variation of a terminal device during a second time period.
The method of claim 14, wherein the measurement configuration comprises the threshold height, and the measurement configuration further comprises at least one of:

a regular interval;

a third time period; or

an initial reference height.
A method of communication, comprising:

receiving, at a terminal device, from a core network device, extended tracking area information, the extended tracking area information comprising one or more additional tracking areas;

receiving, at the terminal device, from an access network device, an aerial height threshold; and

in response to a height of the terminal device exceeds the aerial height threshold, performing, at the terminal device, tracking area updating based on the extended tracking area information.
A method of communication, comprising:

transmitting, at an access network device, to a terminal device, an aerial height threshold;

determining, at the access network device, aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information, the extended tracking area information comprising one or more additional tracking areas; and

transmitting, at the access network device, to a core network device, the aerial state information for the terminal device.
A method of communication, comprising:

transmitting, at a core network device, towards a terminal device, extended tracking area information, the extended tracking area information comprising one or more additional tracking areas;

receiving, at the core network device, from an access network device, aerial state information for the terminal device, the aerial state information indicating use of the extended tracking area information; and

paging, at the core network device, the terminal device based on the extended tracking area information.
A method of communication, comprising:

receiving, at a terminal device, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising one or more additional notification areas;

receiving, at the terminal device, an aerial height threshold; and

in response to a height of the terminal device exceeds the aerial height threshold, performing, at the terminal device, RNA updating based on the extended RNA information.
A method of communication, comprising:

transmitting, at an access network device, extended radio access network, RAN, based notification area, RNA, information, the extended RNA information comprising one or more additional notification areas;

transmitting, at the access network device, an aerial height threshold;

determining, at the access network device, aerial state information for a terminal device, the aerial state information indicating whether a height of the terminal device exceeds the aerial height threshold; and

in accordance with a determination that the height of the terminal device exceeds the aerial height threshold, paging, at the access network device, the terminal device based on the extended RNA information.
A terminal device comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the terminal device to perform the method according to any of claims 1-6, or claims 7-13, or claim 17 or claim 20.
An access network device comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the access network device to perform the method according to any of claims 14-16, or claim 18 or claim 21.
A core network device comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the core network device to perform the method according to claim 19.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 1-6, or claims 7-13, or claims 14-16, or claim 17, or claim 18, or claim 19, or claim 20, or claim 21.