WO2020029173A1

WO2020029173A1 - Method, device and computer readable medium for random access

Info

Publication number: WO2020029173A1
Application number: PCT/CN2018/099608
Authority: WO
Inventors: Hua Chao; Haitao Li
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2018-08-09
Filing date: 2018-08-09
Publication date: 2020-02-13
Also published as: CN112544118A

Abstract

Method, device and computer readable medium are disclosed for random access. The method comprises determining, at a network device, random access resources for at least one terminal device group (210). The method further comprises triggering, by the network device, random access procedures for the at least one terminal device group by providing the at least one terminal device group with information about the random access resources (220).

Description

METHOD, DEVICE AND COMPUTER READABLE MEDIUM FOR RANDOM ACCESS

FIELD

Embodiments of the present disclosure generally relate to the field of telecommunications, and in particular, to a method, device and computer readable medium for random access.

BACKGROUND

With the rapid deployment of Internet of Things (IoT) services or applications, the number of terminal devices in IoT dramatically increased in the past years and is foreseen keeping the trend in the future. The terminal devices may be located at multiple geographic places, and many of the terminal devices are delay-tolerant. Different IoT services could be provided with different QoS requirements. In the fifth generation (5G) new radio (NR) scope, massive Machine Type Communications (mMTC) are specified to consider corresponding challenges.

In current cellular network, terminal devices access the network spontaneously by using random access resources broadcasted in the system information block (SIB) . A network device responds access requests from the terminal devices reactively. Multiple mechanisms are designed in the 3 ^rd generation project partner (3GPP) to control the load distribution in the cellular network. The mechanisms may include random access control, radio admission control, load balancing and so on. When congestion is detected by the network device, the network device may limit access behaviours of the terminal devices by access barring and/or rejection of part or all radio resource control (RRC) connection establishment requests. When the load of a cell is saturated, handover, cell reselection and/or RRC connection release may be triggered to offload or reduce the load of the cell directly. However, all of the mechanisms are reactive. It means that the network device can only start to solve problems when the problems really happen or are detected.

SUMMARY

In general, example embodiments of the present disclosure provide a method, device and computer readable medium for random access.

In a first aspect, a method for random access is provided. The method comprises: determining, at a network device, random access resources for at least one terminal device group; and triggering, by the network device, random access procedures for the at least one terminal device group by providing the at least one terminal device group with information about the random access resources.

In some embodiments, a plurality of terminal devices are grouped into the at least one terminal device group based on at least one of the following: service access classes for the plurality of terminal devices, wherein each of the service access classes is associated with Quality of Service requirement, identifiers of the plurality of terminal devices, and one or more paging groups to which the plurality of terminal devices belong.

In some embodiments, the information about the random access resources comprises at least one of the following: group information about the at least one terminal device group, an effective period during which the random access resources can be used by the at least one terminal device group to initiate the random access procedures, and locations of the random access resources during the effective period.

In some embodiments, providing the at least one terminal device group with the information about the random access resources comprises: transmitting paging messages to the at least one terminal device group, wherein each of the paging messages comprises the effective period and the locations of the random access resources, the group information is determined based on paging frames associated with the at least one terminal device group.

In some embodiments, providing the at least one terminal device group with the information about the random access resources comprises: transmitting paging messages to the at least one terminal device group, wherein each of the paging messages comprises the group information, the effective period and the locations of the random access resources.

In some embodiments, providing the at least one terminal device group with the information about the random access resources comprises: broadcasting the locations of the random access resources via system information; and transmitting paging messages or downlink control information, DCI, to the at least one terminal device group, wherein each of the paging messages or the DCI comprises the group information and the effective period.

In some embodiments, triggering the random access procedures for the at least one terminal device group comprises: triggering random access procedures for a first terminal device group by providing the first terminal device group with first information about a first random access resource set; and triggering random access procedures for a second terminal device group by providing the second terminal device group with second information about a second random access resource set.

In some embodiments, providing the first terminal device group with the first information comprises: providing an indication in the first information, wherein the indication indicates that a terminal device belonging to both of the first terminal device group and the second terminal device group should use the first random access resource set to initiate a random access procedure.

In some embodiments, the method further comprises: allocating to the terminal device uplink resources in a first uplink grant and uplink resources in a second uplink grant, wherein the first uplink grant is associated with the first terminal device group and the second uplink grant is associated with the second terminal device group.

In some embodiments, the method further comprises: allocating to the terminal device uplink resources in an uplink grant, wherein the uplink grant is associated with the first terminal device group and the second terminal device group.

In a second aspect, a method for random access is provided. The method comprises: receiving from a network device, at a terminal device belonging to a terminal device group, information about random access resources for the terminal device group; determining whether the terminal device is triggered to initiate a random access procedure based on the information; and in response to determining that the terminal device is triggered, initiating the random access procedure by using one of the random access resources.

In some embodiments, the terminal device is grouped into the terminal device group based on at least one of the following: a service access class for the terminal device, wherein the service access class is associated with Quality of Service requirement, an identifier of the terminal device, and a paging group to which the terminal device belongs.

In some embodiments, the information about the random access resources comprises at least one of the following: group information about the terminal device group, an effective period during which the random access resources can be used by the terminal device group to initiate random access procedures, and locations of the random access resources during the effective period.

In some embodiments, receiving the information about random access resources comprises: receiving, from the network device, a paging message that comprises the information about random access resources.

In some embodiments, determining whether the terminal device is triggered comprises: in response to determining that the paging message comprises the effective period and the locations of the random access resources, determining that the terminal device is triggered.

In some embodiments, determining whether the terminal device is triggered comprises: in response to determining that the paging message comprises the group information about the terminal device group, determining that the terminal device is triggered.

In some embodiments, receiving the information about random access resources comprises: receiving the locations of the random access resources via system information broadcast by the network device; and receiving, from the network device, a paging message or downlink control information, DCI, wherein the paging message or the DCI comprises the group information and the effective period.

In some embodiments, the terminal device belongs to both of the terminal device group and a further terminal device group; receiving the information about random access resources comprises: receiving first information about a first random access resource set for the terminal device group; and receiving second information about a second random access resource set for the further terminal device group; and initiating the random access procedure comprises: initiating the random access procedure by using one of the first random access resource set and the second random access resource set.

In some embodiments, receiving the first information comprises: receiving an indication in the first information, wherein the indication indicates that the terminal device should use the first random access resource set to initiate the random access procedure; and initiating the random access procedure comprises: initiating the random access procedure by using the first random access resource set.

In some embodiments, initiating the random access procedure comprises: in response to selecting the first random access resource set, initiating the random access procedure by using the first random access resource set.

In some embodiments, the method further comprises: transmitting to the network device an indication indicating that the terminal device belongs to both of the terminal device group and a further terminal device group.

In some embodiments, initiating the random access procedure comprises: identifying locations of the random access resources; randomly selecting one of the random access resources; and initiating the random access procedure by using the selected random access resource.

In some embodiments, initiating the random access procedure comprises: comparing a first number of resources in the first random access resource set and a second number of resources in the second random access resource set; and in response to the first number being greater than the second number, initiating the random access procedure by using the first random access resource set.

In a third aspect, there is provided a device for random access. The device comprises at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the device to perform the method according to the first aspect.

In a fourth aspect, there is provided a device for random access. The device comprises at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the device to perform the method according to the second aspect.

In a fifth aspect, there is provided a computer-readable medium storing a computer program thereon. The computer program, when executed by a processor, causes the processor to carry out the method according to the first aspect.

In a sixth aspect, there is provided a computer-readable medium storing a computer program thereon. The computer program, when executed by a processor, causes the processor to carry out the method according to the second aspect.

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

BRIEF DESCRIPTION OF THE DRAWINGS

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 shows an example communication network in which embodiments of the present disclosure can be implemented;

Fig. 2 is a flowchart of a method for random access in accordance with some embodiments of the present disclosure;

Fig. 3 is a schematic diagram of effective periods of random access resources in accordance with some embodiments of the present disclosure;

Fig. 4 is a flowchart of a method for random access in accordance with some embodiments of the present disclosure; and

Fig. 5 is a 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 example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

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

As used herein, the term “communication network” refers to a network that follows any suitable communication standards or protocols such as long term evolution (LTE) , LTE-Advanced (LTE-A) and 5G NR, and employs any suitable communication technologies, including, for example, MIMO, OFDM, time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, machine type communication (MTC) , eMBB, mMTC and uRLLC technologies. For the purpose of discussion, in some embodiments, the LTE network, the LTE-Anetwork, the 5G NR network or any combination thereof is taken as an example of the communication network.

As used herein, the term “network device” refers to any suitable device at a network side of a communication network. The network device may include any suitable device in an access network of the communication network, for example, including a base station (BS) , a relay, an access point (AP) , a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a gigabit NodeB (gNB) , a Remote Radio Module (RRU) , a radio header (RH) , a remote radio head (RRH) , a low power node such as a femto, a pico, and the like. For the purpose of discussion, in some embodiments, the eNB is taken as an example of the network device.

The network device may also include any suitable device in a core network, for example, including multi-standard radio (MSR) radio equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs) , Multi-cell/multicast Coordination Entities (MCEs) , Mobile Switching Centers (MSCs) and 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) , and/or Mobile Data Terminals (MDTs) .

As used herein, the term “terminal device” refers to a device capable of, configured for, arranged for, and/or operable for communications with a network device or a further terminal device in a communication network. The communications may involve transmitting and/or receiving wireless signals using electromagnetic signals, radio waves, infrared signals, and/or other types of signals suitable for conveying information over air. In some embodiments, the terminal device may be configured to transmit and/or receive information without direct human interaction. For example, the terminal device may transmit information to the network device on predetermined schedules, when triggered by an internal or external event, or in response to requests from the network side.

Examples of the terminal device include, but are not limited to, user equipment (UE) such as smart phones, wireless-enabled tablet computers, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , and/or wireless customer-premises equipment (CPE) . For the purpose of discussion, in the following, some embodiments will be described with reference to UEs as examples of the terminal devices, and the terms “terminal device” and “user equipment” (UE) may be used interchangeably in the context of the present disclosure.

As used herein, the term “cell” refers to an area covered by radio signals transmitted by a network device. The terminal device within the cell may be served by the network device and access the communication network via the network device.

As used herein, the term “circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) ; and (b) combinations of hardware circuits and software, such as (as applicable) : (i) a combination of analog and/or digital hardware circuit (s) with software/firmware and (ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) ; and (c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or 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 “based at least in part on” . The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment” . The term “another embodiment” is to be read as “at least one other embodiment” . Other definitions, explicit and implicit, may be included below.

As used herein, a downlink (DL) transmission refers to a transmission from a network device to a terminal device, and an uplink (UL) transmission refers to a transmission in an opposite direction. That is, in DL, the network device is a transmitter and the terminal device is a receiver device; while in UL, the terminal device is a transmitter and the network device is a receiver device.

Fig. 1 shows an example communication network 100 in which embodiments of the present disclosure can be implemented. As shown, the wireless communication network 100 may include one or more network devices, for example, a network device 110. The network device 110 may be in a form of a base station (BS) , a Node B (NB) , an evolved NB (eNB) , a gNB, a virtual BS, a Base Transceiver Station (BTS) , or a Base Station Subsystem (BSS) , AP and the like.

The network device 110 may provide service to a plurality of terminal devices 120-1, 120-2, 120-3 and 120-4, which are collectively referred to as “terminal devices 120” or each of which is individually referred to as “terminal device 120” , within its coverage 112. It should be appreciated that in some embodiments, the network device may provide service to less or more terminal devices and the number of the terminal devices in this example does not suggest any limitations to the scope of the present disclosure.

In current 3GPP specification, a network device configures random access parameters in SIB. The random access parameters include random access opportunity (RAO) , number of non-dedicated random access preambles and preamble division to indicate message 3 (Msg3) size differentiation. The RAO refers to time-frequency resources a terminal device can use to send preamble to the network device. During a random access procedure, a terminal device selects the first available RAO to send its preamble to the network device.

Due to limited number of RAOs and limited number of the non-dedicated random access preambles, arrival burst or access burst of a large amount of terminal devices in MTC or IoT could happen with high probability. It means that the large amount of terminal devices may access the network at the same time. As a consequence, it probably leads to high access collision rate, high access failure rate and large access delay. Both the network performance and experiences of the terminal devices are reduced accordingly.

In this event, a solution for random access triggered by a network device is proposed. In this solution, a plurality of terminal devices are grouped into at least one terminal device group. The network device transmits explicit notification to at least one terminal device group so as to invite the at least one terminal device group to initiate random access procedures. Upon receiving the notification, the terminal devices belonging to the at least one terminal device group know that they are allowed to transmit uplink (UL) traffic data and then initiate the random access procedure. With this solution, the network device may control attempts time of random accesses from a large amount of terminal devices so as to proactively balance load of a cell over time before congestion or overload happens.

Principle and embodiments of the present disclosure will be described in detail below with reference to Fig. 2, which is a flowchart of a method 200 for random access in accordance with some embodiments of the present disclosure. For example, the method 200 can be implemented at the network device 110 as shown in Fig. 1. It is to be understood that the method 200 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 210, the network device 110 determines random access resources for at least one terminal device group.

In some embodiments, the terminal devices 120-1 to 120-4 may be grouped into at least one terminal device group based on service access classes (SACs) for the terminal devices. Each of the SACs is associated with Quality of Service (QoS) requirement. The QoS requirement may be associated with a type of service supported by a terminal device. In some embodiments, the terminal devices 120-1 to 120-4 may be pre-configured with respective SACs. For example, the SACs may be stored in subscriber identity module (SIM) cards of the terminal devices 120-1 to 120-4.

In some embodiments, if a terminal device supports different types of services, more than one SACs may be pre-configured for this terminal device.

In some embodiments, the terminal devices 120-1 to 120-4 may support the same type of service and thus have the same QoS requirement. Accordingly, the terminal devices 120-1 to 120-4 may be pre-configured with the same SAC. In such embodiments, the terminal devices 120-1 to 120-4 may be grouped into at least one terminal device group based on identifiers of the terminal devices 120-1 to 120-4.

In other embodiments, the terminal devices 120-1 to 120-4 may be grouped into at least one terminal device group based on one or more paging groups to which the terminal devices 120-1 to 120-4 belong. For example, if the terminal devices 120-1 and 120-2 belong to a first paging group and the terminal devices 120-3 and 120-4 belong to a second different paging group, the terminal devices 120-1 and 120-2 may be grouped into a terminal device group and the terminal devices 120-3 and 120-4 may be grouped into a further terminal device group.

At block 220, the network device 110 triggers random access procedures for the at least one terminal device group by providing the at least one terminal device group with information about the random access resources.

In accordance with the embodiments of the present disclosure, the network device transmits explicit notification to at least one terminal device group so as to invite the at least one terminal device group to initiate random access procedures. Thus, the network device may control attempts time of random accesses from a large amount of terminal devices so as to proactively balance load of a cell over time before congestion or overload happens. Because the number of terminal devices to be triggered may be configured by the network device, network resource consumption can be controlled and congestion or overload can be avoided. In addition, the network device differentiates the random access resources per terminal device group and thus different QoS requirements for different terminal device groups may be met.

In some embodiments, the information about the random access resources comprises group information about the at least one terminal device group. In the embodiments where the terminal devices 120-1 to 120-4 are grouped into at least one terminal device group based on their SACs, their SACs may be used as group indexes.

In some embodiments, the information about the random access resources comprises an effective period during which the random access resources can be used by the at least one terminal device group to initiate the random access procedures, and locations of the random access resources during the effective period.

Because a terminal device can use a random access resource configured by the network device to initiate a random access procedure, the random access resource is also referred to as a random access opportunity (RAO) . In embodiments of the present disclosure, because the network device proactively balances load of a cell over time before congestion or overload happens, random access resources configured by the network device in accordance with the embodiments of the present disclosure are also referred to as proactive RAOs.

Fig. 3 is a schematic diagram of proactive RAOs and effective periods of the proactive RAOs in accordance with some embodiments of the present disclosure. As shown, a first terminal device group (which is also referred to as group 1) is configured with a first random access resource set having an effective period 310. There are six proactive RAOs during the effective period 310. Terminal devices in the first terminal device group may select any of the six proactive RAOs to initiate random access procedures. A second terminal device group (which is also referred to as group 2) is configured with a second random access resource set having an effective period 320. There are four proactive RAOs during the effective period 320. Terminal devices in the second terminal device group may select any of the four proactive RAOs to initiate random access procedures. Because the network device may configure more than one proactive RAOs for each terminal device group, collision rate may be reduced.

It should be noted that the proactive RAOs are not overlapped with conventional RAOs. Thus, the solution in accordance with the present disclosure has no impact to conventional RACH procedures.

In some embodiments, the network device may control the load of a cell by configuring random access resources for one or more groups of terminal devices and triggering random access procedures for the one or more groups of terminal devices. For example, in the case where less network resources are available for random access, the network device may trigger random access procedures for one group of terminal devices. For another example, in the case where more network resources are available for random access, the network device may trigger random access procedures for more than one groups of terminal devices.

In some embodiments, the network device 110 may determines a first random access resource set for a first terminal device group and a second random access resource set for a second terminal device group. The network device 110 may trigger random access procedures for the first terminal device group by providing the first terminal device group with first information about the first random access resource set, and trigger random access procedures for the second terminal device group by providing the second terminal device group with second information about the second random access resource set.

In such embodiments, the network device 110 may provide an indication in the first information about the first random access resource set. The indication indicates that a terminal device belonging to both of the first terminal device group and the second terminal device group should use the first random access resource set to initiate a random access procedure.

In some embodiments, the first random access resource set may be different from the second random access resource set. For example, a length of an effective period for the first random access resource set may be different from a length of an effective period for the second random access resource set, as shown in Fig. 3. A density of proactive RAOs, for example, the number of proactive RAOs per radio frame, during the effective period for the first random access resource set may be different from a density of proactive RAOs during the effective period for the second random access resource set, as shown in Fig. 3. In this way, the network may control the load of a cell.

In some embodiments, the number of random access resources in the first random access resource set may be greater than the number of random access resources in the second random access resource set. For example, as shown in Fig. 3, the number of RAOs 312 in the first random access resource set having the effective period 310 is greater than the number of RAOs 322 in the second random access resource set having the effective period 320.

In such embodiments, the network device 110 may allocate to the terminal device uplink resources in a first uplink grant and uplink resources in a second uplink grant, wherein the first uplink grant is associated with the first terminal device group and the second uplink grant is associated with the second terminal device group. Alternatively, the network device 110 may allocate to the terminal device uplink resources in an uplink grant, wherein the uplink grant is associated with the first terminal device group and the second terminal device group.

In some embodiments, the network device 110 may provide the at least one terminal device group with the information about the random access resources by transmitting paging messages to the at least one terminal device group. Each of the paging messages comprises the effective period and the locations of the random access resources. Thus, the terminal devices receiving the paging messages may determine whether they are triggered based on the effective period and the locations of the random access resources. In such embodiments, no explicit group information is included in the paging messages, and the group information is determined by terminal devices in the at least one terminal device group based on paging frames associated with the at least one terminal device group. The terminal devices in the at least one terminal device group may determine the number of paging frames based on a paging cycle, parameters for paging control channel and identifiers of the terminal devices. For example, the terminal devices 120-1 and 120-2 may determine paging frames # (SFN mod paging cycle = 0) as the paging frame for receiving a paging radio network temporary identity (P-RNTI) , and the terminal devices 120-3 and 120-4 may determine paging frames # (SFN mod paging cycle = 4) as the paging frame for receiving a P-RNTI. Thus, the terminal devices 120-1 and 120-2 may determine that they belong to a terminal device group, and the terminal devices 120-3 and 120-4 may determine that they belong to a further terminal device group.

In some embodiments, the network device 110 may provide the at least one terminal device group with the information about the random access resources by transmitting paging messages to the at least one terminal device group. Each of the paging messages comprises the group information, the effective period and the locations of the random access resources. In such embodiments, explicit group information is included in the paging messages. Thus, the terminal devices receiving the paging messages may determine whether they are triggered based on the explicit group information.

In some embodiments, the network device 110 may broadcast the locations of the random access resources via system information. For example, the network device 110 may broadcast numbers of sub-frames in a radio frame that are defined as RAOs. The network device 110 may transmit paging messages or downlink control information (DCI) to the at least one terminal device group, wherein each of the paging messages or the DCI comprises the group information and the effective period. Since the locations of the random access resources are not conveyed in the paging messages or DCI, overhead of the paging messages or DCI may be reduced.

In some embodiments, the network device 110 may broadcast information about random access resources per group of terminal devices via system information, wherein the information includes the locations of the random access resources, the group information and the effective period. In this case, the effective period is a time period occurring periodically. When a terminal device belonging to a group of terminal devices has UL data to transmit, the terminal device may use the broadcast information about random access resources for this group to initiate a random access procedure. Because each group of terminal devices is configured with the random access resources for this group, random access burst from a large amount of terminal devices may be avoided.

Fig. 4 is a flowchart of a method 400 for random access in accordance with some embodiments of the present disclosure. For example, the method 400 can be implemented at the terminal device 120 as shown in Fig. 1. It is to be understood that the method 400 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 410, the terminal device 120 belonging to a terminal device group receives information about random access resources for the terminal device group, from the network device 110.

At block 420, the terminal device 120 determines whether the terminal device 120 is triggered to initiate a random access procedure based on the received information.

At block 430, if the terminal device 120 determines that the terminal device 120 is triggered, the terminal device 120 initiates the random access procedure by using one of the random access resources.

In some embodiments, the terminal device 120 is grouped into the terminal device group based on at least one of the following: a service access class for the terminal device 120, wherein the service access class is associated with Quality of Service requirement; an identifier of the terminal device 120; and a paging group to which the terminal device 120 belongs.

In some embodiments, the terminal device 120 receives the information about random access resources by receiving a paging message that comprises the information about random access resources.

In such embodiments, no explicit group information is included in the paging message, the effective period and the locations of the random access resources are included in the paging message. The group information is determined by the terminal device 120 based on a paging frame associated with the terminal device 120. For example, if the terminal device 120 determines paging frame # (SFN mod paging cycle = 0) as the paging frame for receiving a P-RNTI, the terminal device 120 is grouped into a terminal device group including all the terminal devices that determine paging frame # (SFN mod paging cycle =0) as the paging frame.

In such embodiments, if the terminal device 120 determines that the paging message comprises the effective period and the locations of the random access resources, the terminal device 120 determines that the terminal device 120 is triggered to initiate a random access procedure.

In some embodiments, explicit group information, the effective period and the locations of the random access resources are included in the paging message. In such embodiments, the terminal device 120 may determine, based on the explicit group information, whether the terminal device 120 is triggered to initiate a random access procedure.

As described above, in the embodiments where the terminal device 120 is grouped into a terminal device group based on the SAC for the terminal device 120, the SAC may be used as a group index. If the paging message comprises a SAC, the terminal device 120 may determine whether the SAC in the paging message is the same as the SAC stored in a SIM card of the terminal device 120. If the SAC in the paging message is the same as the SAC stored in a SIM card of the terminal device 120, the terminal device 120 may determine that the terminal device 120 is triggered to initiate a random access procedure.

In some embodiments, upon determining that the terminal device 120 is triggered, the terminal device 120 may identify the locations of available RAOs and select one of the available RAOs with equal probability for random access attempt. For example, in the example as shown in the Fig. 3, the terminal device 120 belonging to group 1 identifies the locations of available RAOs 312 and randomly selects one of the available RAOs 312 to initiate a random access procedure.

In some embodiments, the terminal device 120 receives the locations of the random access resources via system information broadcast by the network device 110 and receives a paging message or DCI that comprises the group information and the effective period.

In some embodiments, the terminal device 120 may belongs to both of the terminal device group and a further terminal device group. In such embodiments, the terminal device 120 may receive first information about a first random access resource set for the terminal device group and receive second information about a second random access resource set for the further terminal device group. The terminal device 120 may initiate the random access procedure by using one of the first random access resource set and the second random access resource set.

In some embodiments, the terminal device 120 may receive from the network device 110 an indication in the first information about the first random access resource set. The indication indicates that the terminal device 120 should use the first random access resource set to initiate the random access procedure.

In other embodiments, if the terminal device 120 selects the first random access resource set, the terminal device 120 may initiate the random access procedure by using the first random access resource set. For example, if the number of random access resources in the first random access resource set is greater than the number of random access resources in the second random access resource set, the terminal device 120 may select the first random access resource set. Alternatively, the terminal device 120 may randomly select one of the first random access resource set and the second random access resource set to initiate the random access procedure.

In such embodiments, the terminal device 120 may transmit to the network device 110 an indication indicating that the terminal device 120 belongs to both of the terminal device group and the further terminal device group. For example, if the terminal device 120 uses the first random access resource set for the terminal device group, the terminal device 120 may transmit to the network device 110 the group information of the further terminal device group as the indication. This helps the network device 110 to allocate proper UL resources in terms of larger UL grant (including more UL resources) or more than one UL grant. For example, the network device 110 may allocate to the terminal device 120 UL resources in a first uplink grant associated with the terminal device group, and allocate to the terminal device 120 UL resources in a second uplink grant associated with the further terminal device group.

In accordance with the present disclosure, terminal devices indicated by the group information can only access the network by transmitting their random access attempts in the proactive RAOs configured for the group. In the convention random access procedure, each terminal device selects the first available RAO to transmit its preamble once the random access procedure is initiated by the layer 3 or upper layer. Different from the convention random access procedure, the triggered terminal device in accordance with the present disclosure may randomly select one of the available proactive RAOs among all configured proactive RAOs with equal probability. By changing the behaviours of terminal devices in this way, random access attempts from the terminal devices to the network can be randomized over time, which helps to reduce the possibility of access burst.

In some embodiments, an apparatus capable of performing the method 200 (for example, the network device 110) may comprise means for performing the respective steps of the method 200. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some embodiments, the apparatus comprises: means for determining random access resources for at least one terminal device group; and means for triggering random access procedures for the at least one terminal device group by providing the at least one terminal device group with information about the random access resources.

In some embodiments, the means for triggering the random access procedures for the at least one terminal device group comprises: means for triggering random access procedures for a first terminal device group by providing the first terminal device group with first information about a first random access resource set; and means for triggering random access procedures for a second terminal device group by providing the second terminal device group with second information about a second random access resource set.

In some embodiments, the apparatus further comprises: means for allocating to the terminal device uplink resources in a first uplink grant and uplink resources in a second uplink grant, wherein the first uplink grant is associated with the first terminal device group and the second uplink grant is associated with the second terminal device group.

In some embodiments, the apparatus further comprises: means for allocating to the terminal device uplink resources in an uplink grant, wherein the uplink grant is associated with the first terminal device group and the second terminal device group.

In some embodiments, an apparatus capable of performing the method 400 (for example, the terminal device 120) may comprise means for performing the respective steps of the method 400. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some embodiments, the apparatus comprises: means for receiving from a network device, at a terminal device belonging to a terminal device group, information about random access resources for the terminal device group; means for determining whether the terminal device is triggered to initiate a random access procedure based on the information; and means for initiating the random access procedure by using one of the random access resources in response to determining that the terminal device is triggered.

In some embodiments, means for receiving the information about random access resources comprises: receiving, from the network device, a paging message that comprises the information about random access resources.

In some embodiments, means for determining whether the terminal device is triggered comprises: means for determining that the terminal device is triggered in response to determining that the paging message comprises the effective period and the locations of the random access resources.

In some embodiments, means for determining whether the terminal device is triggered comprises: means for determining that the terminal device is triggered in response to determining that the paging message comprises the group information about the terminal device group.

In some embodiments, means for receiving the information about random access resources comprises: means for receiving the locations of the random access resources via system information broadcast by the network device; and means for receiving, from the network device, a paging message or downlink control information, DCI, wherein the paging message or the DCI comprises the group information and the effective period.

In some embodiments, the terminal device belongs to both of the terminal device group and a further terminal device group; means for receiving the information about random access resources comprises: means for receiving first information about a first random access resource set for the terminal device group; and means for receiving second information about a second random access resource set for the further terminal device group; and means for initiating the random access procedure comprises: means for initiating the random access procedure by using one of the first random access resource set and the second random access resource set.

In some embodiments, means for receiving the first information comprises: means for receiving an indication in the first information, wherein the indication indicates that the terminal device should use the first random access resource set to initiate the random access procedure; and means for initiating the random access procedure comprises: means for initiating the random access procedure by using the first random access resource set.

In some embodiments, means for initiating the random access procedure comprises: means for initiating the random access procedure by using the first random access resource set in response to selecting the first random access resource set.

In some embodiments, the apparatus further comprises: means for transmitting to the network device an indication indicating that the terminal device belongs to both of the terminal device group and a further terminal device group.

In some embodiments, means for initiating the random access procedure comprises: means for identifying locations of the random access resources; means for randomly selecting one of the random access resources; and means for initiating the random access procedure by using the selected random access resource.

In some embodiments, means for initiating the random access procedure comprises: means for comparing a first number of resources in the first random access resource set and a second number of resources in the second random access resource set; and means for initiating the random access procedure by using the first random access resource set in response to the first number being greater than the second number.

Fig. 5 is a simplified block diagram of a device 500 that is suitable for implementing embodiments of the present disclosure. The device 500 can be considered as a further example implementation of the network device 101 as shown in Fig. 1. Accordingly, the device 500 can be implemented at or as at least a part of the network device 110 or the terminal device 120.

As shown, the device 500 includes a processor 510, a memory 520 coupled to the processor 510, a suitable transmitter (TX) and receiver (RX) 540 coupled to the processor 510, and a communication interface coupled to the TX/RX 540. The memory 520 stores at least a part of a program 530. The TX/RX 540 is for bidirectional communications. The TX/RX 540 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 UE.

The program 530 is assumed to include program instructions that, when executed by the associated processor 510, enable the device 500 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Figs. 1 to 10. The embodiments herein may be implemented by computer software executable by the processor 510 of the device 500, or by hardware, or by a combination of software and hardware. The processor 510 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 510 and memory 520 may form processing means 550 adapted to implement various embodiments of the present disclosure.

The memory 520 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 520 is shown in the device 500, there may be several physically distinct memory modules in the device 500. The processor 510 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 500 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 representations, it is to be understood that the block, apparatus, system, technique or method 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

methods

200, 400 as described above with reference to Figs. 2 and 4. 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.

In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable media.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer 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 computer 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 languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A method for random access, comprising:

determining, at a network device, random access resources for at least one terminal device group; and

triggering, by the network device, random access procedures for the at least one terminal device group by providing the at least one terminal device group with information about the random access resources.
The method of Claim 1, wherein a plurality of terminal devices are grouped into the at least one terminal device group based on at least one of the following:

service access classes for the plurality of terminal devices, wherein each of the service access classes is associated with Quality of Service requirement,

identifiers of the plurality of terminal devices, and

one or more paging groups to which the plurality of terminal devices belong.
The method of Claim 1, wherein the information about the random access resources comprises at least one of the following:

group information about the at least one terminal device group,

an effective period during which the random access resources can be used by the at least one terminal device group to initiate the random access procedures, and

locations of the random access resources during the effective period.
The method of Claim 3, wherein providing the at least one terminal device group with the information about the random access resources comprises:

transmitting paging messages to the at least one terminal device group, wherein each of the paging messages comprises the effective period and the locations of the random access resources, the group information is determined based on paging frames associated with the at least one terminal device group.
The method of Claim 3, wherein providing the at least one terminal device group with the information about the random access resources comprises:

transmitting paging messages to the at least one terminal device group, wherein each of the paging messages comprises the group information, the effective period and the locations of the random access resources.
The method of Claim 3, wherein providing the at least one terminal device group with the information about the random access resources comprises:

broadcasting the locations of the random access resources via system information; and

transmitting paging messages or downlink control information, DCI, to the at least one terminal device group, wherein each of the paging messages or the DCI comprises the group information and the effective period.
The method of Claim 1, wherein triggering the random access procedures for the at least one terminal device group comprises:

triggering random access procedures for a first terminal device group by providing the first terminal device group with first information about a first random access resource set; and

triggering random access procedures for a second terminal device group by providing the second terminal device group with second information about a second random access resource set.
The method of Claim 7, wherein providing the first terminal device group with the first information comprises:

providing an indication in the first information, wherein the indication indicates that a terminal device belonging to both of the first terminal device group and the second terminal device group should use the first random access resource set to initiate a random access procedure.
The method of Claim 8, further comprising:

allocating to the terminal device uplink resources in a first uplink grant and uplink resources in a second uplink grant, wherein the first uplink grant is associated with the first terminal device group and the second uplink grant is associated with the second terminal device group.
The method of Claim 8, further comprising:

allocating to the terminal device uplink resources in an uplink grant, wherein the uplink grant is associated with the first terminal device group and the second terminal device group.
A method for random access, comprising:

receiving from a network device, at a terminal device belonging to a terminal device group, information about random access resources for the terminal device group;

determining whether the terminal device is triggered to initiate a random access procedure based on the information; and

in response to determining that the terminal device is triggered, initiating the random access procedure by using one of the random access resources.
The method of Claim 11, wherein the terminal device is grouped into the terminal device group based on at least one of the following:

a service access class for the terminal device, wherein the service access class is associated with Quality of Service requirement,

an identifier of the terminal device, and

a paging group to which the terminal device belongs.
The method of Claim 11, wherein the information about the random access resources comprises at least one of the following:

group information about the terminal device group,

an effective period during which the random access resources can be used by the terminal device group to initiate random access procedures, and

locations of the random access resources during the effective period.
The method of Claim 13, wherein receiving the information about random access resources comprises:

receiving, from the network device, a paging message that comprises the information about random access resources.
The method of Claim 14, wherein determining whether the terminal device is triggered comprises:

in response to determining that the paging message comprises the effective period and the locations of the random access resources, determining that the terminal device is triggered.
The method of Claim 14, wherein determining whether the terminal device is triggered comprises:

in response to determining that the paging message comprises the group information about the terminal device group, determining that the terminal device is triggered.
The method of Claim 13, wherein receiving the information about random access resources comprises:

receiving the locations of the random access resources via system information broadcast by the network device; and

receiving, from the network device, a paging message or downlink control information, DCI, wherein the paging message or the DCI comprises the group information and the effective period.
The method of Claim 11, wherein:

the terminal device belongs to both of the terminal device group and a further terminal device group;

receiving the information about random access resources comprises:

receiving first information about a first random access resource set for the terminal device group; and

receiving second information about a second random access resource set for the further terminal device group; and

initiating the random access procedure comprises:

initiating the random access procedure by using one of the first random access resource set and the second random access resource set.
The method of Claim 18, wherein:

receiving the first information comprises:

receiving an indication in the first information, wherein the indication indicates that the terminal device should use the first random access resource set to initiate the random access procedure; and

initiating the random access procedure comprises:

initiating the random access procedure by using the first random access resource set.
The method of Claim 18, wherein initiating the random access procedure comprises:

comparing a first number of resources in the first random access resource set and a second number of resources in the second random access resource set; and

in response to the first number being greater than the second number, initiating the random access procedure by using the first random access resource set.
The method of Claim 18, wherein initiating the random access procedure comprises:

in response to selecting the first random access resource set, initiating the random access procedure by using the first random access resource set.
The method of Claim 21, further comprising:

transmitting to the network device an indication indicating that the terminal device belongs to both of the terminal device group and a further terminal device group.
The method of Claim 11, wherein initiating the random access procedure comprises:

identifying locations of the random access resources;

randomly selecting one of the random access resources; and

initiating the random access procedure by using the selected random access resource.
A network device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the device to perform the method of any of Claims 1 to 10.
A terminal device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the device to perform the method of any of Claims 11 to 23.
A computer-readable medium storing a computer program thereon, the computer program, when executed by a processor, causing the processor to carry out the method of any of Claims 1 to 10.
A computer-readable medium storing a computer program thereon, the computer program, when executed by a processor, causing the processor to carry out the method of any of Claims 11 to 23.