WO2023060601A1

WO2023060601A1 - Method, device and computer readable medium for communication

Info

Publication number: WO2023060601A1
Application number: PCT/CN2021/124227
Authority: WO
Inventors: Gang Wang
Original assignee: Nec Corporation
Priority date: 2021-10-15
Filing date: 2021-10-15
Publication date: 2023-04-20

Abstract

Embodiments of the present disclosure relate to methods, devices and computer readable media for communication. According to embodiments of the present disclosure, a terminal device receives, from a network device, a configuration for a coverage enhancement (CE) random access (RA). The terminal device determines, based on the configuration, whether a first condition is fulfilled. If the first condition is fulfilled, the terminal device determines whether a second condition is fulfilled based on the configuration. If the second condition is fulfilled, the terminal device selects a resource associated with the CE RA. The terminal device performs a RA procedure to the network device based on the selected resource. In this way, it can deal with changed channel conditions and improve probability for successfully access the network.

Description

METHOD, DEVICE AND COMPUTER READABLE MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices and computer storage media for communication.

BACKGROUND

With development of communication technologies, several solutions have been proposed to provide efficient and reliable solutions for communication. For example, Enhanced Coverage technology has been proposed. The usage of Enhanced Coverage may require use of extensive resources (e.g. radio and signaling resources) from the network. This feature enables the operator to prevent specific subscribers from using Enhanced Coverage.

SUMMARY

In general, embodiments of the present disclosure provide methods, devices and computer storage media for communications.

In a first aspect, there is provided a method of communication. The method comprises: receiving, at a terminal device, a configuration for a coverage enhancement (CE) random access (RA) ; in accordance with a determination that a number of unsuccessful RA attempts is not smaller than a threshold number which is indicated in the configuration, determining that a first condition is fulfilled; and selecting a resource for a RA procedure based on the determination.

In a second aspect, there is provided a method of communication. The method comprises: transmitting, at a terminal device and to a core network device, an indication regarding a support for CE authorization; and receiving, from the core network device, CE authorization information which indicate whether an enhanced coverage (EC) functionality is restricted or authorized.

In a third aspect, there is provided a method of communication. The method comprises: receiving, at a core network device and from a terminal device, an indication regarding a support for CE authorization; and transmitting, at the core network device and to the terminal device, CE authorization information which indicate whether an enhanced coverage (EC) functionality is restricted or authorized.

In a fourth aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the terminal device to perform: receiving a configuration for a coverage enhancement (CE) random access (RA) ; in accordance with a determination that a number of unsuccessful RA attempts is not smaller than a threshold number which is indicated in the configuration, determining that a first condition is fulfilled; and selecting a resource for a RA procedure based on the determination.

In a fifth aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the terminal device to perform: transmitting, to a core network device, an indication regarding a support for CE authorization; and receiving, from the core network device, CE authorization information which indicate whether an enhanced coverage (EC) functionality is restricted or authorized.

In a sixth aspect, there is provided a core network device. The core network device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the core network to perform: receiving, from a terminal device, an indication regarding a support for CE authorization; transmitting, to the terminal device, CE authorization information which indicate whether an enhanced coverage (EC) functionality is restricted or authorized.

In a seventh aspect, there is provided a computer readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the first, second, or third aspect of the present disclosure.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

Fig. 1 is a schematic diagram of a communication environment in which embodiments of the present disclosure can be implemented;

Fig. 2 illustrates a signaling flow for communications between devices in accordance with some embodiments of the present disclosure;

Figs. 3A-3C illustrate flow charts of example methods of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

Fig. 4 illustrates a signaling flow for communications between devices in accordance with some embodiments of the present disclosure;

Fig. 5 illustrates a signaling flow for communications between devices in accordance with some embodiments of the present disclosure;

Fig. 6 illustrates a signaling flow for communications between devices in accordance with some embodiments of the present disclosure;

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

Fig. 8 illustrates a flow chart of an example method of communication implemented at a terminal device in accordance with some embodiments of the present disclosure;

Fig. 9 illustrates a flow chart of an example method of communication implemented at a network device in accordance with some embodiments of the present disclosure; and

Fig. 10 is a simplified block diagram of a device that is suitable for implementing 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, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. 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. In addition, the term “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) , a low power node such as a femto node, a pico node, and the like.

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.

As mentioned above, it has been proposed to support enhanced coverage. The UE may indicate its capability of support for restriction of use of Enhanced Coverage in Attach and tracking area update (TAU) procedure for the radio access technology (RAT) it is camping on to a mobility management entity (MME) . The MME receives Enhanced Coverage Restricted parameter from a home subscriber server (HSS) . This parameter is kept as part of subscription data in the HSS and specifies per public land mobile network (PLMN) whether the enhanced coverage functionality is restricted or not for the UE. The UE assumes Enhanced Coverage is allowed unless explicitly restricted by the network for a PLMN. Coverage enhancement obtains coverage gain through multiple repetitions of the physical layer, which occupies wireless resources of the network, but existing mechanism cannot achieve differential billing for coverage enhancement. Channel quality between the terminal device and the network device may vary with time during the overall random access procedure. Due to the deterioration of the channel quality, or the collision, the random access procedure may experience several attempts before successfully completion or indicating a Random Access problem. Thus, it is worth to find out a proper opportunity to evaluate or re-evaluate the criterion for CE RA.

In order to solve at least part of above problems, solutions on coverage enhancements are needed. According to embodiments of the present disclosure, a terminal device receives, from a network device, a configuration for a coverage enhancement (CE) random access (RA) . The terminal device determines, based on the configuration, whether a first condition is fulfilled. If the first condition is fulfilled, the terminal device determines whether a second condition is fulfilled based on the configuration and the CE RA criteria. If the first condition is fulfilled, the terminal device selects a resource associated with for the CE RA. The terminal device performs a RA procedure to the network device based on the selected resource. In this way, it can deal with changed channel conditions and improve probability for successfully access the network.

The term “coverage enhancement (CE) ” used herein can refer to a mechanism that identifies a mobile that supports additional features to enhance operation in poor coverage areas. The term “random access (RA) ” used herein can refer to a mechanism that sets up wireless communication association between a terminal device and a base station.

Fig. 1 illustrates a schematic diagram of a communication system in which embodiments of the present disclosure can be implemented. The communication system 100, which is a part of a communication network, comprises a terminal device 110-1, a terminal device 110-2, ..., a terminal device 110-N, which can be collectively referred to as “terminal device (s) 110. ” The number N can be any suitable integer number.

The communication system 100 further comprises a network device 120 and a network device 130. In the communication system 100, the network devices and the terminal devices can communicate data and control information to each other. The numbers of terminal devices and network devices shown in Fig. 1 are given for the purpose of illustration without suggesting any limitations. The communication system 100 can comprise a core network device 140. In some embodiments, the core network device 140 can comprise one of more of: a MME, an access and mobility management function (AMF) , or a unified data management (UDM) entity.

Communications in the communication system 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.

Fig. 2 shows a signaling chart illustrating process 200 among devices according to some example embodiments of the present disclosure. Only for the purpose of discussion, the process 200 will be described with reference to Fig. 1. The process 200 may involve the terminal device 110-1 and the network device 120 in Fig. 1. It should be noted that the process 200 is only an example not limitation.

The network device 120 transmits 2010 a configuration of CE RA to the terminal device 110-1. In some embodiments, the configuration of the CE RA can be broadcasted in system information. Alternatively, the configuration of the CE RA can be transmitted via RRC signaling. In this way, it assistants terminal devices to find out a proper opportunity to evaluate or re-evaluate the criterion for CE RA.

In some embodiments, the configuration may indicate a threshold number. For example, the threshold number can be smaller than the maximum number of preamble transmissions. In some embodiments, the configuration may indicate that the CE RA criteria can be evaluated based on an initiation of the random access procedure. Alternatively or in addition, the configuration may indicate a threshold reference signal received power (RSRP) which is associated with triggering the CE RA.

In some embodiments, the configuration may comprise a first configuration for CE RA on a normal uplink. Alternatively or in addition, the configuration may comprise a second configuration for CE RA on a supplementary uplink. For example, the first configuration may comprise a first threshold number for CE RA on the normal uplink and the second configuration may comprise a second threshold number for CE RA on the supplementary uplink.

The terminal device 110-1 may determine 2015 the number of previous unsuccessful RA attempts. The term “random access attempt” used herein can refer to one time process where the terminal device tries to access the channel. In some embodiments, if the terminal device 110-1 does not successfully receive a random access response (RAR) from the network device 120, the terminal device 110-1 can determine that the RA attempt is failed. In this case, for example, if the terminal device 110-1 does not receive the RAR within a receiving window, the terminal device 110-1 can determine that the RA attempt is failed. In other embodiments, if the terminal device 110-1 does not receive the RAR before an expiration of a timer (in other words, before the ra-ResponseWindow expires) , the terminal device 110-1 can determine that the RA attempt is failed. The number of the unsuccessful RA attempts can be recorded by a counter, for example, the preamble_transmission_counter.

Alternatively, if the contention resolution is unsuccessful, the terminal device 110-1 can determine that the RA attempt is failed. For example, if the terminal device 110-1 does not successfully receive or decode message 4, the terminal device 110-1 can determine that the RA attempt is failed. In some embodiments, if the ra-ContentionResolutionTimer expires, the terminal device 110-1 can determine that the RA attempt is failed. In other embodiments if the terminal device does not decode a UE Contention Resolution Identity in the MAC CE matches the CCCH SDU transmitted in Msg3, the terminal device 110-1 can determine that the RA attempt is failed.

The terminal device 110-1 determines 2020 whether a first condition is fulfilled based on the configuration. In some embodiments, the CE RA criteria may comprise a criterion to request a message 3 repetition. Alternatively, the CE RA criteria may comprise a criterion to apply a message A repetition. In other embodiments, the CE RA criteria may comprise a criterion to apply physical random access channel (PRACH) repetition. In some embodiments, the CE RA criteria may also comprise a criterion to apply message 1/preamble repetition. In an example embodiment, if the first condition is fulfilled, the terminal device 110-1 may evaluate the CE RA criteria.

In some embodiments, if the random access procedure is initiated, the terminal device 110-1 may determine that the first condition is fulfilled based on the configuration. Alternatively, if the number of the previous unsuccessful RA attempts is not smaller the threshold number indicated in the configuration, the terminal device 110-1 may determine that the first condition is fulfilled. Alternatively, if the number of the previous unsuccessful RA attempts is below the threshold number, the terminal device 110-1 may determine that the first condition is not fulfilled.

The terminal device 110-1 may determine 2030 whether a second condition is fulfilled. For example, the terminal device 110-1 may determine a reference signal received power (RSRP) at the terminal device 110-1. In this case, if the RSRP is not below a threshold RSRP, the terminal device 110-1 may determine that the second condition is fulfilled. The second condition can refer to the CE RA criteria. The procedure of determining whether the second condition is fulfilled can refer to evaluating the CE RA criteria. If the second condition is fulfilled, the CE RA can be triggered.

The terminal device 110-1 selects 2040 a resource for a RA procedure based on the determination regarding whether the first condition is fulfilled. The resource may comprise a synchronization signal/physical broadcast channel (SS/PBCH) block (SSB) information. Alternatively or in addition, the resource may comprise random access channel (RACH) resources, for example, preamble resources, RO (Random access occasion) resources.

In an example embodiment, if the first condition is not fulfilled, the terminal device 110-1 may determine whether to select the resource associated with CE RA based on previous CE RA criteria evaluation. For example, the terminal device 110-1 may perform CE RA criteria evaluation when initiate random access procedure. If the terminal device 110-1 determined to select the resource not associated with the CE RA according to the evaluation performed when initiated the random access procedure, the terminal device 110-1 may also select the resource which is not associated with the CE RA for the current RA attempt. In this case, in some embodiments, the terminal device 110-1 may select the resource from a set of resources which are not used for the CE RA for the previous random access. Alternatively, the terminal device 110-1 may select the resource from a set of total resources regardless whether the sources in the set of total resources are associated with the CE RA or not.

Alternatively, if the terminal device 110-1 determined to select the resource which is associated with the CE RA according to the evaluation performed when initiated the random access procedure, the terminal device 110-1 may select the resource which is associated with for the CE RA for the current random access attempt.

In other embodiments, if the terminal device 110-1 determined to select the resource not associated with the CE RA according to the evaluation performed when initiated the random access procedure. For the subsequent random access attempt, if the first condition is not fulfilled, the terminal device 110-1 may select the resource from the resources which are not associated with the CE RA. If the first condition is fulfilled, for random access attempt, the terminal device 110-1 may select the resource associated with the CE RA.

In some embodiments, the terminal device 110-1 may select the resource associated with the CE RA without backoff time upon the second condition being fulfilled. In this way, without waiting an extra backoff time, it can reduce delay of accessing the network. Alternatively, the terminal device 110-1 may select the resource associated with the CE RA after the backoff time, in this way, it can reduce the probability of collision and improve the probability for successfully access.

The terminal device 110-1 may perform 2050 the RA procedure based on the selected resource. For example, the terminal device 110-1 may transmit a preamble on the selected resource.

The terminal device 110-1 may store 2060 CE RA related information. In some embodiments, the CE RA related information may comprise whether a message 3 repetition is applied. If the message 3 repetition is applied and the message 3 repetition is defined with different repetition levels, the CE RA related information may also comprise repetition level information of the message 3 repetition, for example, repetition number. Alternatively or in addition, the CE RA related information may comprise whether PRACH repetition is applied. If the PRACH repetition is applied and the PRACH repetition is defined with different repetition levels, the CE RA related information may also comprise repetition level information of the PRACH repetition, for example, repetition number. In other embodiments, the CE RA related information may indicate the n ^th RA attempt where the CE RA is applied for the RA attempt but the CE RA is not applied for a previous RA attempt of the RA attempt.

The terminal device 110-1 may transmit 2070 an indication to the network device 120. The indication can indicate an availability of a connection establishment failure (CEF) report. The indication can be transmitted in an uplink RRC message. For example, the indication can be transmitted in one of the followings: a RRCResume complete message, a RRCReconfiguration complete message, a RRCReestablishment complete message or a UE information response message. The network device 120 may transmit 2080 a request for the CEF report to the terminal device 110-1. The terminal device 110-1 may transmit 2090 the CEF report to the network device 120. The CEF report can comprise the CE RA related information. In this way, the information included in CEF report can be used for RACH Optimization (e.g., Optimization of the threshold, such as preambleTrans_CE) .

Referring to Figs. 3A-3C, Figs. 3A-3C show flow charts of example methods of communication at the terminal device, respectively. It should be noted that the orders of the blocks shown in Figs. 3A-3C are only examples not limitations. Moreover, one or more of the blocks can be omitted in some example embodiments.

Fig. 3A shows a flowchart of an example method 310 in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 310 can be implemented at the terminal device 110-1 as shown in Fig. 1.

In some embodiments, at block 3101, the terminal device 110-1 may select a NUL or a SUL. In some embodiments, at block 3102, the terminal device 110-1 may select 2 step random access or 4 step random access. It should be noted that

blocks

3101 and 3102 can be optional and can take place in different order.

The terminal device 110-1 may determine, at block 3103, whether the second condition is fulfilled. If the second condition is fulfilled, the terminal device 110-1 may select the resource associated with the CE RA, at block 3108. In this case, at block 3109, the terminal device 110-1 may perform the RA attempt using the selected resource associated with the CE RA. The resource may comprise a synchronization signal/physical broadcast channel (SS/PBCH) block (SSB) information. Alternatively or in addition, the resource may comprise random access channel (RACH) resources, e.g., preamble resources, RO (Random access occasion) resources. It should be noted that the block 3103 can be optional. For example, the block 3103 can be omitted for the first random access attempt.

If the second condition is not fulfilled, the terminal device 110-1 may select the resource which is not associated with the CE RA. Furthermore, the terminal device 110-1 may select the resource for the RA procedure based on the RSRP, at block 3104. For example, if the a RSRP associated with a SSB or a RACH resource is above a RSRP threshold, the terminal device 110-1 may select said SSB or said RACH resource. In some embodiments, the terminal device 110-1 may select a SSB or RACH resource with the largest RSRP. Alternatively, if none of the SSB or RACH resources is above the RSRP threshold, the terminal device 110-1 may select any SSB or RACH resource.

At block 3105, the terminal device 110-1 may perform the RA attempt using the selected resource. The terminal device 110-1 may determine whether the RA attempt is successful at block 3106. For example, if the terminal device 110-1 does not receive a random access response (RAR) from the network device 120, the terminal device 110-1 can determine that the RA attempt is failed. In this case, for example, if the terminal device 110-1 does not receive the RAR within a receiving window, the terminal device 110-1 can determine that the RA attempt is failed. In other embodiments, if the terminal device 110-1 does not receive the RAR before an expiration of a timer, the terminal device 110-1 can determine that the RA attempt is failed. Alternatively, if the contention resolution is unsuccessful, the terminal device 110-1 can determine that the RA attempt is failed.

At block 3107, if the RA attempt is not successful and next attempt is needed, the terminal device 110-1 may determine whether the first condition is fulfilled. If the first condition fulfilled, the terminal device 110-1 may go to block 3103 and determine whether the second condition is fulfilled. If the second condition is fulfilled, the terminal device 110-1 may select the resource associated with the CE RA, at block 3108. In this case, at block 3109, the terminal device 110-1 may perform the RA attempt using the selected resource associated with the CE RA.

According to embodiments shown in Fig. 3A, the terminal device may evaluate the CE RA criteria at an initial random access attempt and the terminal device may re-evaluate the CE RA criteria after several random access attempts. In this way, the terminal device is able to evaluate the CE RA criteria considering the changed channel conditions. In other embodiments, the terminal device may not evaluate the CE RA criteria at an initial random access attempt and directly select the resource not associate with CE RA, as time goes by, after several random access attempts when the first condition fulfilled, the terminal device evaluate the CE RA criteria and further determine whether to perform CE RA using CE RA resources. In this way, it can cope with the varying channel quality and improve the probability of successfully accessing the network.

Fig. 3B shows a flowchart of an example method 320 for further selecting SSB or a RACH resource from the selected CE RA resources in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 320 can be implemented at the terminal device 110-1 as shown in Fig. 1. The example method 320 may be implemented at block 3104 shown in Fig. 3A.

At block 3201, the terminal device 110-1 determines whether the RSRP of the resources associated with the CE RA is above a threshold RSRP. For example, if the a RSRP associated with a SSB or a RACH resource is above a RSRP threshold, the terminal device 110-1 may, at block 3202, select said SSB or said RACH resource. In some embodiments, the terminal device 110-1 may select a SSB or RACH resource with the largest RSRP. Alternatively, if none of the SSB or RACH resources is above the RSRP threshold, the terminal device 110-1 may, at block 3203, select any SSB or RACH resource associated with the CE RA.

In some embodiments, if the first condition is not fulfilled, for next RA attempt, the terminal device 110-1 may determine whether to select the resources associated with the CE RA based on the previous CE RA criteria evaluation. Alternatively, the terminal device may not evaluate the CE RA criteria when initiate random access, with the first condition is not fulfilled, the resource can be select from the resource not associated with the CE RA.

In other embodiments, if the first the condition is fulfilled, the terminal device 110-1 may perform the resource selection without backoff time. In this way, without waiting an extra backoff time, it can reduce delay of accessing the network. Alternatively, the terminal device 110-1 may select the resource associated with the CE RA after the backoff time, in this way, it can reduce the probability of collision and improve the probability for successfully access.

Fig. 3C shows a flowchart of an example method 330 in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 330 can be implemented at the terminal device 110-1 as shown in Fig. 1.

In some embodiments, at block 3301, the terminal device 110-1 may select a NUL or a SUL. In some embodiments, at block 3302, the terminal device 110-1 may select 2 step random access or 4 step random access. It should be noted that

blocks

3301 and 3302 can be optional and can take place in different order.

In some embodiments, the terminal device 110-1 may determine, at block 3303, whether the second condition is fulfilled. In some embodiments, if the second condition is fulfilled, the terminal device 110-1 my select the resource associated with the CE RA, at block 3108. In this case, at block 3309, the terminal device 110-1 may perform the RA attempt using the selected resource associated with the CE RA. It should be noted that the block 3103 can be optional. For example, the block 3103 can be omitted for the first random access attempt.

In some embodiments, the terminal device may determine whether the second condition is fulfilled when initiate the random access procedure. If the second condition is not fulfilled, the terminal device 110-1 may select the resource not associate with CE RA. In other embodiments, the terminal device may not evaluate the CE RA criteria at an initial random access attempt and directly select the resource not associate with CE RA. When further selecting SSB or a RACH resource from the selected resources not associate with CE RA, the terminal device 110-1 may select the resource for the RA procedure based on the RSRP, at block 3304. For example, if the a RSRP associated with a SSB or a RACH resource is above a RSRP threshold, the terminal device 110-1 may select said SSB or said RACH resource. In some embodiments, the terminal device 110-1 may select a SSB or RACH resource with the largest RSRP. Alternatively, if none of the SSB or RACH resources is above the RSRP threshold, the terminal device 110-1 may select any SSB or RACH resource.

At block 3305, the terminal device 110-1 may perform the RA attempt using the selected resource. The terminal device 110-1 may determine whether the RA attempt is successful at block 3306. For example, if the terminal device 110-1 does not receive a RAR from the network device 120, the terminal device 110-1 can determine that the RA attempt is failed. Alternatively, if the contention resolution is unsuccessful, the terminal device 110-1 can determine that the RA attempt is failed.

At block 3307, if the RA attempt is not successful, the terminal device 110-1 may determine whether the first condition is fulfilled. If the first condition fulfilled, the terminal device 110-1 may go to block 3308 and select the resource associated with the CE RA, at block 3308. In this case, at block 3309, the terminal device 110-1 may perform the RA attempt using the selected resource associated with the C E RA.

According to embodiments shown in Fig. 3C, the terminal device may evaluate the CE RA criteria at an initial random access attempt. In other embodiments, the terminal device may not evaluate the CE RA criteria at an initial random access attempt and directly select the resource not associate with CE RA, as time goes by, when the first condition is fulfilled, the terminal device has experienced several unsuccessfully random access attempts which may resulted by deterioration of the channel quality, the terminal device perform CE RA for the next attempt. In this way, it can cope with the varying channel quality and improve the probability of successfully accessing the network.

Fig. 4 shows a signaling chart illustrating process 400 among devices according to some other example embodiments of the present disclosure. Only for the purpose of discussion, the process 400 will be described with reference to Fig. 1. The process 400 may involve the terminal device 110-1 and the network device 120 in Fig. 1. The process may also involve an AMF 410 and a UDM 420. It should be noted that the process 400 is only an example not limitation.

The terminal device 110-1 may transmit 4010 an indication regarding a support for CE authorization to the AMF 410. In some embodiments, the indication can be transmitted in a registration request. Alternatively, the indication can be transmitted in a registration update request. In other embodiments, the indication can be transmitted in a TAU request.

The UDM 420 can keep the CE authorization information as part of subscription data. The CE authorization information may indicate whether enhanced coverage (EC) functionality is restricted or authorized. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) . Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a tracking area (TA) . In other embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a TA list. The CE authorization information may also indicate whether the EC functionality is restricted or authorized in a set of cells. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a frequency band. Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized for a UE type.

In some embodiments, the EC functionality may comprise a usage of message 3 repetition. Alternatively or in addition, the EC functionality may comprise a usage of message A repetition. In other embodiments, the EC functionality may comprise a usage of PRACH repetition. In some embodiments, the EC functionality may comprise PUSCH enhancements. The EC functionality may also comprise PUCCH enhancements.

The UDM 420 may transmit 4030 the CE authorization information to the AMF 410. The AMF 410 may store 4040 the CE authorization information.

The AMF 410 may transmit 4050 the authorization information to the network device 120. In this case, the authorization information can be transmitted in an initial context setup request message. The AMF 410 may transmit 4060 the authorization information to the terminal device 110-1. In this case, the authorization information can be transmitted in a response message. In some embodiments, the authorization information can be transmitted in a registration message. Alternatively, the authorization information can be transmitted in a registration update message. In other embodiments, the authorization information can be transmitted in a TAU message. The terminal device 110-1 may determine 4070 of the EC functionality is applied based on the authorization information. In this way, it can control the use of NR coverage enhancement functions and achieve differential billing for coverage enhancement.

For example, if the CE authorization information indicates “restrict” of a coverage enhancement function, the terminal device 110-1 should not use the corresponding function. Alternatively, if the CE authorization information indicates “authorized” of a coverage enhancement function, the terminal device 110-1 can be permitted to use the corresponding function, and network also provides corresponding resources.

In some embodiments, the use of the message 3 repetition can be restricted or authorized for partial beams or RACH resources. For example, if the use of the message 3 repetition is restricted, the terminal device 110-1 may only select RACH resources not related to SSB that enables message 3 repetition. Alternatively, the terminal device 110-1 may only select RACH resources which are not associated with the CE RA. In some embodiments, if the use of the message 3 repetition is not restricted, the terminal device 110-1 may select RACH resources related to SSB that enables msg3 repetition.

In other embodiments, if the use of the message 3 repetition is not restricted, the terminal device 110-1 can select RACH resources related to SSB that enables message 3 repetition. Alternatively, the terminal device 110-1 may select RACH resources related to SSB that enables message 3 repetition only after the first condition is fulfilled. If the use of the message 3 repetition is restricted, the terminal device 110-1 cannot select beams or RACH resources associated with the CE RA.

Additionally, the terminal device 110-1 may be authorized to use enhanced coverage functionalities based on different cell camping criteria (cell selection and reselection criteria) . If the terminal device 110-1 determines that coverage enhancement can be used (CE is supported by UE and Cell A and not restrict in Cell A) , the cell selection criterion S should be compensate with an offset: Srxlev_CE > 0, where Srxlev_CE represents Srxlev compensated with an offset due to coverage enhancement and Squal > 0 or Squal_CE > 0. The parameter “Srxlev” represents a cell reception level. For Inter-frequency and inter-RAT cell reselection evaluation, Srxlev_CE and/or Squal_CE can also be used. For Intra-frequency and equal priority inter-frequency Cell Reselection: Rn and Rs should also be compensated by an offset if UE determined that coverage enhancement can be used in the corresponding cell.

After the network device 120 receives the coverage enhancement authorization information reported by the terminal device 110-1 or transmitted by CN or transmitted by other base stations, the network device 120 does not use the resources corresponding to coverage enhancement in resource configuration and scheduling for unauthorized terminal device.

Fig. 5 shows a signaling chart illustrating process 500 among devices according to some other example embodiments of the present disclosure. Only for the purpose of discussion, the process 500 will be described with reference to Fig. 1. The process 500 may involve the network device 120 and the network device 130 in Fig. 1. The process may also involve a CN device 510. It should be noted that the process 500 is only an example not limitation.

The CN device 510 may store 5010 CE authorization information in the mobility management context. The CN device 510 may transmit 5020 S1 paging message to the network device 130 which is the last serving network device of the terminal device 110-1. The S1 paging message may comprise the CE authorization information.

The CN device 510 may transmit 5030 S1 paging message to the network device 120. The S1 paging message may comprise the CE authorization information.

Fig. 6 shows a signaling chart illustrating process 600 among devices according to some other example embodiments of the present disclosure. Only for the purpose of discussion, the process 600 will be described with reference to Fig. 1. The process 600 may involve the terminal device 110-1, the network device 120 and the network device 130 in Fig. 1. It should be noted that the process 600 is only an example not limitation.

The network device 130 may trigger 130 a RAN paging. The network device 130 may transmit 6020 a RAN paging message to the network device 120. The RAN paging message may comprise the CE authorization information. The network device 120 may page 6030 the terminal device 110-1.

Fig. 7 shows a flowchart of an example method 700 in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 700 can be implemented at the terminal device 110-1 as shown in Fig. 1.

At block 710, the terminal device 110-1 receives a configuration of CE RA from the network device 120. In some embodiments, the configuration of the CE RA can be broadcasted in system information. Alternatively, the configuration of the CE RA can be transmitted via RRC signaling. In this way, it assistants terminal devices to find out a proper opportunity to evaluate or re-evaluate the criterion for CE RA.

In some embodiments, the configuration may comprise a first configuration for CE RA on a normal uplink. Alternatively or in addition, the configuration may comprise a second configuration for CE RA on a supplementary uplink. For example, the first configuration may comprise a first threshold number for the normal uplink and the second configuration may comprise a second threshold number for the supplementary uplink.

The terminal device 110-1 may determine the number of previous unsuccessful RA attempts. In some embodiments, if the terminal device 110-1 does not successfully receive a random access response (RAR) from the network device 120, the terminal device 110-1 can determine that the RA attempt is failed. In this case, for example, if the terminal device 110-1 does not receive the RAR within a receiving window, the terminal device 110-1 can determine that the RA attempt is failed. In other embodiments, if the terminal device 110-1 does not receive the RAR before an expiration of a timer (in other words, before the ra-ResponseWindow expires) , the terminal device 110-1 can determine that the RA attempt is failed.

At block 720, the terminal device 110-1 determines whether a first condition is fulfilled based on the configuration. The terminal device 110-1 may determine the number of previous unsuccessful RA attempts. In some embodiments, the CE RA criteria may comprise a criterion to request a message 3 repetition. Alternatively, the CE RA criteria may comprise a criterion to apply a message A repetition. In other embodiments, the CE RA criteria may comprise a criterion to apply physical random access channel (PRACH) repetition. In some embodiments, the CE RA criteria may also comprise a criterion to apply message 1 or preamble repetition. In an example embodiment, if the first condition is fulfilled, the terminal device 110-1 may evaluate the CE RA criteria. Alternatively, the terminal device 110-1 may use the CE RA criteria after the first condition is fulfilled.

In some embodiments, the terminal device 110-1 may determine whether a second condition is fulfilled. For example, the terminal device 110-1 may determine a reference signal received power (RSRP) at the terminal device 110-1. In this case, if the RSRP is not below a threshold RSRP, the terminal device 110-1 may determine that the second condition is fulfilled. The second condition can refer to the CE RA criteria. The procedure of determining whether the second condition is fulfilled can refer to evaluating the CE RA criteria. If the second condition is fulfilled, the CE RA can be triggered.

At block 730, the terminal device 110-1 selects a resource for a RA procedure based on the determination regarding whether the first condition is fulfilled. The resource may comprise a synchronization signal/physical broadcast channel (SS/PBCH) block (SSB) information. Alternatively or in addition, the resource may comprise random access channel (RACH) resources, for example, preamble resources, RO (Random access occasion) resources.

Alternatively, if the terminal device 110-1 determined to select the resource which is associated with the CE RA according to the evaluation performed when initiated the random access procedure, the terminal device 110-1 may select the resource which is associated with for the CE RA for the current random access attempt. In other embodiments, if the terminal device 110-1 determined to select the resource not associated with the CE RA according to the evaluation performed when initiated the random access procedure. For the subsequent random access attempt, if the first condition is not fulfilled, the terminal device 110-1 may select the resource from the resources which are not associated with the CE RA. If the first condition is fulfilled for the random access attempt, the terminal device 110-1 may select the resource associated with the CE RA.

The terminal device 110-1 may perform the RA procedure based on the selected resource. For example, the terminal device 110-1 may transmit a preamble on the selected resource.

In some embodiments, the terminal device 110-1 may store CE RA related information. In some embodiments, the CE RA related information may comprise whether a message 3 repetition is applied. If the message 3 repetition is applied and the message 3 repetition is defined with different repetition levels, the CE RA related information may also comprise repetition level information of the message 3 repetition, for example, repetition number. Alternatively or in addition, the CE RA related information may comprise whether PRACH repetition is applied. If the PRACH repetition is applied and the PRACH repetition is defined with different repetition levels, the CE RA related information may also comprise repetition level information of the PRACH repetition, for example, repetition number. In other embodiments, the CE RA related information may indicate the n ^th RA attempt where the CE RA is applied for the RA attempt but the CE RA is not applied for a previous RA attempt of the RA attempt.

The terminal device 110-1 may transmit an indication to the network device 120. The indication can indicate an availability of a connection establishment failure (CEF) report. The indication can be transmitted in an uplink RRC message. For example, the indication can be transmitted in one of the followings: a RRCResume complete message, a RRCReconfiguration complete message, a RRCReestablishment complete message or a UE information response message. The network device 120 may transmit a request for the CEF report to the terminal device 110-1. The terminal device 110-1 may transmit the CEF report to the network device 120. The CEF report can comprise the CE RA related information. In this way, the information included in CEF report can be used for RACH Optimization (e.g., Optimization of the threshold, such as preambleTrans_CE) .

Fig. 8 shows a flowchart of an example method 800 in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 800 can be implemented at the terminal device 110-1 as shown in Fig. 1.

At block 810, the terminal device 110-1 transmits an indication regarding a support for CE authorization to the core network device 140. In some embodiments, the indication can be transmitted in a registration request. Alternatively, the indication can be transmitted in a registration update request. In other embodiments, the indication can be transmitted in a TAU request.

At block 820, the terminal device 110-1 receives the CE authorization information from the core network device 140. The CE authorization information may indicate whether enhanced coverage (EC) functionality is restricted or authorized. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) . Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a tracking area (TA) . In other embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a TA list. The CE authorization information may also indicate whether the EC functionality is restricted or authorized in a set of cells. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a frequency band. Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized for a UE type.

Fig. 9 shows a flowchart of an example method 900 in accordance with an embodiment of the present disclosure. Only for the purpose of illustrations, the method 900 can be implemented at the core network device 140 as shown in Fig. 1.

At block 910, the core network device 140 receives an indication regarding a support for CE authorization from the terminal device 110-1. In some embodiments, the indication can be transmitted in a registration request. Alternatively, the indication can be transmitted in a registration update request. In other embodiments, the indication can be transmitted in a TAU request.

At block 930, the core network device 140 transmits the CE authorization information to the terminal device 110-1.

The CE authorization information may indicate whether enhanced coverage (EC) functionality is restricted or authorized. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) . Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a tracking area (TA) . In other embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a TA list. The CE authorization information may also indicate whether the EC functionality is restricted or authorized in a set of cells. In some embodiments, the CE authorization information may indicate whether the EC functionality is restricted or authorized in a frequency band. Alternatively or in addition, the CE authorization information may indicate whether the EC functionality is restricted or authorized for a UE type.

In some embodiment, a terminal device comprises circuitry configured to receive a configuration for a coverage enhancement (CE) random access (RA) ; in accordance with a determination that a number of unsuccessful RA attempts is not smaller than a threshold number which is indicated in the configuration, determine that a first condition is fulfilled; and select a resource for a RA procedure based on the determination.

In some embodiment, the terminal device comprises circuitry configured to in accordance with a determination that the first condition is fulfilled, determine whether a second condition is fulfilled based on the configuration. In some embodiments, the terminal device comprises circuitry configured to select the resource for the RA procedure by in accordance with a determination that the second condition is fulfilled, selecting a resource associated with the CE RA as the resource for the RA procedure; and perform a RA procedure to the network device based on the resource associated with the CE RA.

In some embodiment, the terminal device comprises circuitry configured to determine a reference signal received power (RSRP) at the terminal device; and in accordance with a determination that the RSRP is below a threshold RSRP which is indicated in the configuration, determine that the second condition is fulfilled.

In some embodiment, the terminal device comprises circuitry configured to select a resource associated with the CE RA by selecting the resource associated with the CE RA without backoff time upon a second condition being fulfilled.

In some embodiment, the terminal device comprises circuitry configured to select the resource for the RA procedure by in accordance with a determination that the first condition is fulfilled for a current RA procedure, selecting a resource associated with the CE RA as the resource for the RA procedure.

In some embodiment, the terminal device comprises circuitry configured to store CE RA related information, wherein the CE RA related information comprises at least one of: whether a message 3 is applied, whether a message A repetition is applied, or whether a physical random access channel (PRACH) repetition is applied.

In some embodiment, the terminal device comprises circuitry configured to transmit a connection establishment failure (CEF) report to the network device, wherein the CEF report comprises the CE RA related information.

In some embodiment, a terminal device comprises circuitry configured to transmit, at a terminal device and to a core network device, an indication regarding a support for CE authorization; and receive, from the core network device, CE authorization information which indicates whether an enhanced coverage (EC) functionality is restricted or authorized.

In some embodiments, the CE authorization information comprises at least one of: whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) , whether the EC functionality is restricted or authorized in a tracking area (TA) , whether the EC functionality is restricted or authorized in a TA list, whether the EC functionality is restricted or authorized in a set of cells, whether the EC functionality is restricted or authorized in a frequency band, or whether the EC functionality is restricted or authorized for a user equipment (UE) type.

In some embodiments, the EC functionality comprises at least one of: a usage of message 3 or message A repetition or PRACH repetition, physical uplink shared channel (PUSCH) enhancements, or physical uplink control channel (PUCCH) enhancements.

In some embodiments, a core network device comprises circuitry configured to receive, at a core network device and from a terminal device, an indication regarding a support for CE authorization; and transmit, at the core network device and to the terminal device, CE authorization information which indicates whether an enhanced coverage (EC) functionality is restricted or authorized.

Fig. 10 is a simplified block diagram of a device 1000 that is suitable for implementing embodiments of the present disclosure. The device 1000 can be considered as a further example implementation of the network device 120, or the terminal device 110 or the core network device 140 as shown in Fig. 1. Accordingly, the device 1000 can be implemented at or as at least a part of the terminal device 110, or the network device 120 or the core network device 140.

As shown, the device 1000 includes a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transmitter (TX) and receiver (RX) 1040 coupled to the processor 1010, and a communication interface coupled to the TX/RX 1040. The memory 1010stores at least a part of a program 1030. The TX/RX 1040 is for bidirectional communications. The TX/RX 1040 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 eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 1030 is assumed to include program instructions that, when executed by the associated processor 1010, enable the device 1000 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Figs. 2 to 9. The embodiments herein may be implemented by computer software executable by the processor 1010 of the device 1800, or by hardware, or by a combination of software and hardware. The processor 1010 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 810 and memory 1020 may form processing means adapted to implement various embodiments of the present disclosure.

The memory 1020 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 1020 is shown in the device 1800, there may be several physically distinct memory modules in the device 1800. The processor 810 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 1800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

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

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to Figs. 2 to 9. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

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

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

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

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

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) , 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.

The term “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) , and the like.

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 (24.25GHz to 71GHz) , frequency band larger than 100GHz 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 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.

Claims

A communication method, comprising:

receiving, at a terminal device, a configuration for a coverage enhancement (CE) random access (RA) ;

in accordance with a determination that a number of unsuccessful RA attempts is not smaller than a threshold number which is indicated in the configuration, determining that a first condition is fulfilled; and

selecting a resource for a RA procedure based on the determination.
The method of claim 1, further comprising:

in accordance with a determination that the first condition is fulfilled, determining whether a second condition is fulfilled based on the configuration; and

wherein selecting the resource for the RA procedure comprises:

in accordance with a determination that the second condition is fulfilled, selecting a resource associated with the CE RA as the resource for the RA procedure; and

performing the RA procedure to a network device based on the resource associated with the CE RA.
The method of claim 2, wherein determining whether the second condition is fulfilled comprises:

determining a reference signal received power (RSRP) at the terminal device; and

in accordance with a determination that the RSRP is below a threshold RSRP which is indicated in the configuration, determining that the second condition is fulfilled.
The method of claim 2, wherein selecting the resource associated with the CE RA comprises:

selecting the resource associated with the CE RA without backoff time upon the second condition being fulfilled.
The method of claim 1, wherein selecting the resource for the RA procedure comprises:

in accordance with a determination that the first condition is fulfilled for a current RA procedure, selecting a resource associated with the CE RA as the resource for the RA procedure.
The method of claim 1, wherein the configuration comprises at least one of:

a first threshold number for CE RA on a normal uplink, or

a second threshold number for CE RA on a supplementary uplink.
The method of claim 1, further comprising:

storing CE RA related information, wherein the CE RA related information comprises at least one of:

whether a message 3 is applied,

whether a message A repetition is applied, or

whether a physical random access channel (PRACH) repetition is applied.
The method of claim 7, wherein the CE RA related information further comprises:

a number of the message 3 repetition,

a number of the message A repetition, or

a number of the PRACH repetition.
The method of claim 7 or 8, further comprising:

transmitting a connection establishment failure (CEF) report to the network device, wherein the CEF report comprises the CE RA related information.
A communication method, comprising:

transmitting, at a terminal device and to a core network device, an indication regarding a support for CE authorization; and

receiving, from the core network device, CE authorization information which indicates whether an enhanced coverage (EC) functionality is restricted or authorized.
The method of claim 10, wherein the CE authorization information comprises at least one of:

whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) ,

whether the EC functionality is restricted or authorized in a tracking area (TA) ,

whether the EC functionality is restricted or authorized in a TA list,

whether the EC functionality is restricted or authorized in a set of cells,

whether the EC functionality is restricted or authorized in a frequency band, or

whether the EC functionality is restricted or authorized for a user equipment (UE) type.
The method of claim 11, wherein the EC functionality comprises at least one of:

a usage of message 3/message A repetition/PRACH repetition,

physical uplink shared channel (PUSCH) enhancements, or

physical uplink control channel (PUCCH) enhancements.
A communication method, comprising:

receiving, at a core network device and from a terminal device, an indication regarding a support for CE authorization; and

transmitting, at the core network device and to the terminal device, CE authorization information which indicates whether an enhanced coverage (EC) functionality is restricted or authorized.
The method of claim 13, wherein the CE authorization information comprises at least one of:

whether the EC functionality is restricted or authorized in a public land mobile network (PLMN) ,

whether the EC functionality is restricted or authorized in a tracking area (TA) ,

whether the EC functionality is restricted or authorized in a TA list,

whether the EC functionality is restricted or authorized in a set of cells,

whether the EC functionality is restricted or authorized in a frequency band, or

whether the EC functionality is restricted or authorized for a user equipment (UE) type.
The method of claim 14, wherein the EC functionality comprises at least one of:

a usage of message 3 repetition,

physical uplink shared channel (PUSCH) enhancements, or

physical uplink control channel (PUCCH) enhancements.
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 1-9 or any of claims 10-12.
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 any of claims 13-15.
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 1-9 or any of claims 10-12 or any of claims 13-15.