WO2025123717A1

WO2025123717A1 - Re-access for a-iot system

Info

Publication number: WO2025123717A1
Application number: PCT/CN2024/110481
Authority: WO
Inventors: Jing HAN; Jie Hu; Haiming Wang; Luning Liu; Lihua Yang
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2024-08-07
Filing date: 2024-08-07
Publication date: 2025-06-19
Anticipated expiration: 2027-02-07

Abstract

Various aspects of the present disclosure relate to re-access for an ambient Internet of things (A-IoT) system. In an aspect, if a first device determines an access failure related to A-IoT communication to a second device, it determines a resource for an access occasion for re-access to the second device. Moreover, the first device performs re-access to the second device based on the resource. In this way, it is allowed to improve the flexibility and efficiency of communications in the A-IoT system.

Description

RE-ACCESS FOR A-IOT SYSTEM

TECHNICAL FIELD

The present disclosure relates to wireless communications, and more specifically to re-access for an ambient Internet of things (A-IoT) system.

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations (BSs) , which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication device, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

A wireless communication system may include an A-IoT device, which has a lower capability in terms of complexity and power consumption. In this case, the wireless communication system may also be referred to as an A-IoT system. Multiple topologies, for example, Topologies 1 to 4, are supported for the A-IoT device. In Topology 1, the A-IoT device directly and bidirectionally communicates with a BS. In Topology 2, the A-IoT device communicates bidirectionally with an intermediate node between the A-IoT device and a BS. In Topology 3, the A-IoT device communicates unidirectionally with a BS and communicates uidirectionally with an assisting node. In Topology 4, the A-IoT device communicates bidirectionally with a UE. However, some studies regarding the A-IoT system, especially, studies on re-access for the A-IoT system considering the above topologies, are still needed.

SUMMARY

The present disclosure relates to methods, apparatuses, and systems that support re-access for the A-IoT system. With the apparatuses and methods, it is allowed to improve the flexibility and efficiency of communications in the A-IoT system.

In some implementations, there is provided a first device. The first device comprises at least one memory, and at least one processor coupled with the at least one memory and configured to cause the first device to: based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determine a resource for an access occasion for re-access to the second device, and perform re-access to the second device based on the resource.

In some implementations, there is provided a method performed by the first device. The method comprises: based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determining a resource for an access occasion for re-access to the second device, and performing re-access to the second device based on the resource.

In some implementations, there is provided a processor for wireless communication. The processor comprises at least one controller coupled with at least one memory and configured to cause the processor to: based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determine a resource for an access occasion for re-access to the second device, and perform re-access to the second device based on the resource.

In some implementations of the method and the first device described herein, determining the resource for re-access may comprise obtaining resource information indicating one or more resources for re-access, the resource information comprising one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access, or time-domain resource information indicating one or more time-domain resources for re-access.

In some implementations of the method and the first device described herein, the one or more frequency-domain resources may comprise at least one frequency available to re-access of one or more frequencies for random access, or a separate frequency for re-access. In some implementations of the method and the first device described herein, the time-domain resource information may indicate a parameter corresponding to a frequency-domain resource of the one or more frequency-domain resources, the parameter being used for determining one or more time slots for re-access.

In some implementations of the method and the first device described herein, determining the resource for re-access may comprise selecting the resource for re-access from the one or more resources indicated in the resource information, and the resource for re-access may be selected randomly, or based on one or more of the following a capability of the first device, a device type of the first device, energy status of the first device, or a priority indication of the one or more resources.

In some implementations of the method and the first device described herein, obtaining the resource information may comprise obtaining the resource information based on an access trigger message received from the second device. In some implementations of the method and the first device described herein, the access trigger message may be an access trigger message for the access occasion, and the one or more resources indicated in the resource information may be associated with the access occasion.

In some implementations of the method and the first device described herein, obtaining the resource information may comprise obtaining the resource information based on an adjust access trigger message received from the second device. In some implementations of the method and the first device described herein, the adjust access trigger message may indicate one or more adjusted resources for initial random access, and some implementations of the method and the first device described herein may further include obtaining an indication indicating that the one or more adjusted resources are available to re-access, from the adjust access trigger message or a paging message. In some implementations of the method and the first device described herein, the adjust access trigger message may indicate one or more adjusted resources for initial random access and the one or more resources for re-access.

Some implementations of the method and the first device described herein may further include storing target resource information obtained from a target message received from the second device, the target resource information indicating one or more of the following: one or more resources for random access, or the one or more resources for re-access. In some implementations of the method and the first device described herein, obtaining the resource information may comprise obtaining the resource information based on the stored target resource information. In some implementations of the method and the first device described herein, wherein the target resource information may indicate the one or more resources for random access, and the target message may further comprise an indication indicating whether the one or more resources for random access are available to re-access, and determining the resource for re-access may comprise based on determining that the one or more resources for random access are available to re-access, determining the resource for re-access based on the one or more resources for random access. In some implementations of the method and the first device described herein, the target message may comprise one of a paging message or an access trigger message.

In some implementations of the method and the first device described herein, obtaining the resource information may comprise obtaining the resource information based on a message received from the second device after an access trigger message for the access occasion and before an access trigger message for a next access occasion. In some implementations of the method and the first device described herein, the resource information may indicate one or more time-domain resources, and determining the resource for re-access comprises selecting a time-domain resource for re-access from the one or more time-domain resources, and determining a frequency-domain resource for re-access as a same frequency-domain resource for random access for the access occasion.

In some implementations of the method and the first device described herein, obtaining the resource information may comprise obtaining the resource information based on an access trigger message for the access occasion received from the second device, and the time-domain resource information may comprise one or more time-domain offsets of the one or more time-domain resources for re-access relative to a time-domain reference point, and/or the frequency-domain resource information may comprise one or more frequency-domain offsets of one or more frequency-domain resources for re-access relative to a frequency-domain reference point. In some implementations of the method and the first device described herein, the time-domain reference point may comprise one of the following: a starting point of message 1 transmission for the access occasion, an ending point of the message 1 transmission, or a time when the first device determines the access failure In some implementations of the method and the first device described herein, the frequency-domain reference point may comprise a frequency for random access for the access occasion.

In some implementations of the method and the first device described herein, the first device may comprise an A-IoT device, and the second device may comprise one of a relay, an integrated access backhaul (IAB) node, a user equipment (UE) , a repeater, or a base station (BS) .

In some implementations, there is provided a second device. The second device comprises at least one memory, and at least one processor coupled with the at least one memory and configured to cause the second device to: transmit, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access, or time-domain resource information indicating one or more time-domain resources for re-access.

In some implementations, there is provided a method performed by the second device. The method comprises: transmitting, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access, or time-domain resource information indicating one or more time-domain resources for re-access

In some implementations, there is provided a processor for wireless communication. The processor comprises at least one controller coupled with at least one memory and configured to cause the processor to: transmit, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access, or time-domain resource information indicating one or more time-domain resources for re-access.

In some implementations of the method and the second device described herein, the one or more frequency-domain resources may comprise at least one frequency available to re-access of one or more frequencies for random access, or a separate frequency for re-access. In some implementations of the method and the second device described herein, the time-domain resource information may indicate a parameter corresponding to a frequency-domain resource of the one or more frequency-domain resources, the parameter being used for determining one or more time slots for re-access.

In some implementations of the method and the second device described herein, the resource information may be transmitted in one of the following: an access trigger message, an adjust access trigger message, a message after an access trigger message for the access occasion and before an access trigger message for a next access occasion, In some implementations of the method and the second device described herein, the adjust access trigger message may indicate one or more adjusted resources for initial random access, and the one or more adjusted resources may be indicated to be available to re-access in the adjust access trigger message or a paging message. In some implementations of the method and the second device described herein, the adjust access trigger message may indicate one or more adjusted resources for initial random access and the one or more resources for re-access.

Some implementations of the method and the second device described herein may further include transmitting, to the first device, a target message comprising target resource information, the target resource information indicating one or more of the following: one or more resources for random access, or the one or more resources for re-access, and wherein the target resource information may be stored at the first device, and the resource information indicating the one or more resources for re-access may be obtained by the first device based on the stored target resource information. In some implementations of the method and the second device described herein, the target resource information may indicate the one or more resources for random access, and the target message may further comprise an indication indicating whether the one or more resources for random access are available to re-access. In some implementations of the method and the second device described herein, the target message may comprise one of a paging message or an access trigger message.

In some implementations of the method and the second device described herein, the resource information may be transmitted in an access trigger message for the access occasion. In some implementations of the method and the second device described herein, the time-domain resource information may comprise one or more time-domain offsets of the one or more time-domain resources for re-access relative to a time-domain reference point. In some implementations of the method and the second device described herein, the frequency-domain resource information may comprise one or more frequency-domain offsets of one or more frequency-domain resources for re-access relative to a frequency-domain reference point. In some implementations of the method and the second device described herein, the time-domain reference point may comprise one of the following: a starting point of message 1 transmission for the access occasion, an ending point of the message 1 transmission, or a time when the first device determines the access failure. In some implementations of the method and the second device described herein, the frequency-domain reference point may comprise a frequency for random access for the access occasion.

In some implementations of the method and the second device described herein, the first device may comprise an A-IoT device, and the second device may comprise one of a relay, an integrated access backhaul (IAB) node, a user equipment (UE) , a repeater, or a base station (BS) .

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example of a wireless communications system that supports re-access for the A-IoT system in accordance with aspects of the present disclosure;

FIG. 1B illustrates an example of Topology 1 associated with aspects of the present disclosure;

FIG. 1C illustrates an example of Topology 2 associated with aspects of the present disclosure;

FIG. 1D illustrates an example of Topology 3 associated with aspects of the present disclosure;

FIG. 1E illustrates an example of Topology 4 associated with aspects of the present disclosure;

FIG. 1F illustrates another example of a wireless communications system associated with aspects of the present disclosure;

FIG. 2 illustrates an example process flow in accordance with some example embodiments of the present disclosure;

FIGS. 3A to 3C illustrate example frequency division multiplexing (FDM) cases in accordance with some example embodiments of the present disclosure;

FIG. 4 illustrates an example of a device that supports re-access for the A-IoT system in accordance with aspects of the present disclosure;

FIG. 5 illustrates an example of a processor that supports re-access for the A-IoT system in accordance with aspects of the present disclosure; and

FIGS. 6 through 7 illustrate flowcharts of methods that support re-access for the A-IoT system in accordance with aspects of the present disclosure.

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

DETAILED DESCRIPTION

Principles 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 limitation as to the scope of the disclosure. The disclosure described herein may 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.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. 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. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as, 5G new radio (NR) , LTE, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) , and so on. Further, the communications between a UE and a network device in the communication network may be performed according to any suitable generation communication protocols, including but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the 4G, 4.5G, the 5G communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will also be future type communication technologies and systems in which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned systems.

As used herein, the term “network device” generally refers to a node in a communication network via which a UE can access the communication network and receive services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , a radio access network (RAN) node, an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , an infrastructure device for a vehicle-to-everything (V2X) communication, a transmission and reception point (TRP) , a reception point (RP) , a remote radio head (RRH) , a relay, an integrated access and backhaul (IAB) node, a low power node such as a femto a base station (BS) , a pico BS, and so forth, depending on the applied terminology and technology. The network device may further refer to a network function (NF) in the core network, for example, a service management function (SMF) , an access and mobility management function (AMF) , a policy control function (PCF) , a user plane function (UPF) or devices with same function in future network architectures, and so forth.

As used herein, the term “user equipment (UE) ” generally refers to any end device that may be capable of wireless communications. By way of example rather than a limitation, a UE may also be referred to as a communication device, a terminal device, an end user device, a subscriber station (SS) , an unmanned aerial vehicle (UAV) , a portable subscriber station, a mobile station (MS) , or an access terminal (AT) . The UE may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet, a wearable UE, a personal digital assistant (PDA) , a portable computer, a desktop computer, an image capture UE such as a digital camera, a gaming UE, a music storage and playback appliance, a vehicle-mounted wireless UE, a wireless endpoint, a mobile station, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , a USB dongle, a smart device, wireless customer-premises equipment (CPE) , an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device (for example, a remote surgery device) , an industrial device (for example, a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms: “UE, ” “communication device, ” “terminal, ” and “UE, ” may be used interchangeably.

As used herein, the term “A-IoT device” refers to a device without batteries or with limited energy storage capabilities. For the A-IoT device, energy is provided by harvesting radio waves, light, motion, heat, or any other suitable source. The A-IoT device can also be called a zero-power terminal, a near-zero power terminal, a passive IoT device, an ambient backscatter communication (AmBC) device, a tag, etc. Compared with low-power and wide-coverage services, such as narrow band (NB) IoT, and enhanced machine type communication (eMTC) , A-IoT has lower complexity and lower power consumption, and is suitable for more application scenarios.

As used herein, the term “D2R transmission” refers to a transmission initiated by an A-IoT device and transmitted to a reader (such as a BS, an intermediate node, an assisting node, or a UE) . As used herein, the term “R2D transmission” refers to a transmission initiated by a reader and transmitted to an A-IoT device.

Principles and implementations of embodiments of the present disclosure will be described in detail below with reference to the figures.

FIG. 1A illustrates an example of a wireless communications system (or referred to as a communication network) 100 that supports re-access for the A-IoT system in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more network entities 102 (also referred to as network equipment) , one or more UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN) , a base transceiver station, an access point, a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc. ) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet- of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100. In some other implementations, a UE 104 may be mobile in the wireless communications system 100.

The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in FIG. 1A. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment) , as shown in FIG. 1A. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100.

A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102) . In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106) . In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 102 may include one or more of a central unit (CU) , a distributed unit (DU) , a radio unit (RU) , a RAN Intelligent Controller (RIC) (e.g., a Near-Real Time RIC (Near-RT RIC) , a Non-Real Time RIC (Non-RT RIC) ) , a Service Management and Orchestration (SMO) system, or any combination thereof.

An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations) . In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., a layer 3 (L3) , a layer 2 (L2) ) functionality and signaling (e.g., radio resource control (RRC) , service data adaption protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU may be connected to one or more DUs or RUs, and the one or more DUs or RUs may host lower protocol layers, such as a layer 1 (L1) (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, MAC layer) functionality and signaling, and may each be at least partially controlled by the CU.

Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs) . In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU) .

A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., F1, F1-c, F1-u) , and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface) . In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links.

The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106) .

In the wireless communications system 100, the network entities 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

Reference is made to FIGS. 1B to 1E to give example illustrations of the above Topologies 1 to 4. Reference is first made to FIG. 1B, which illustrates an example of Topology 1 associated with aspects of the present disclosure. As shown in FIG. 1B, in Topology 1, an A-IoT device 121 communicates with a BS 122 directly and bi-directionally. The communication between the BS 122 and the A-IoT device 121 includes A-IoT data and/or signalling. This topology includes a possibility of a transmission from the BS 122 to the A-IoT device 121 and a different possibility of a transmission from the A-IoT device 121 to the BS 122.

FIG. 1C illustrates an example of Topology 2 associated with aspects of the present disclosure. As shown in FIG. 1C, in Topology 2, an A-IoT device 131 communicates bidirectionally with an intermediate node 132 between the A-IoT device 131 and base station 133. In this topology, the intermediate node 132 may be a relay node, an IAB node, a UE, a repeater, etc., which is capable of A-IoT. The intermediate node 132 transfers A-IoT data and/or signalling between the BS 133 and the A-IoT device 131.

Topology 3 may comprise two topology types, i.e., Topology 3A and Topology 3B. FIG. 1D illustrates an example of Topology 3 with a topology type of 3B associated with aspects of the present disclosure. In Topology 3B, an A-IoT device 141 receives data/signalling from a BS 142 and transmits data/signalling to an assisting node 143. In this topology, the assisting node 143 may be a relay, an IAB node, a UE, a repeater, etc. which is capable of A-IoT. For Topology 3A, the example illustration of FIG. 1D also applies, only with the difference that it has the opposite direction of the A-IoT data/signaling. In Topology 3A, an A-IoT device 141 transmits data/signalling to a BS 142, and receives data/signalling from an assisting node 143.

FIG. 1E illustrates an example of Topology 4 associated with aspects of the present disclosure. As shown in FIG. 1E, in Topology 4, an A-IoT device 151 communicates bidirectionally with a UE 152. The communication between the UE 152 and the A-IoT device 151 includes A-IoT data and/or signalling.

The above communicate devices involved in Topologies 1 to 4 with reference to FIG. 1B to FIG. 1E may be implemented by devices involved in the wireless communications system 100 as described herein with reference to FIG. 1A. For example, the BS 122, the BS 133, or the BS 142 may be implemented by the base station 102 in FIG. 1A. For example, the BS intermediate node 132 (when implemented by a UE) , the assisting node 143 (when implemented by a UE) , or the UE 152 may be implemented by the UE 104 in FIG. 1A.

FIG. 1F illustrates another example of a wireless communications system 160 associated with aspects of the present disclosure. As shown in FIG. 1F, the wireless communications system 160 may comprise a first device 161 and a second device 162.

To transmit data and/or control information, the first device 161 may perform communications with the second device 162. The communication between the first device 161 and the second device 162 may be direct or indirect. The first device 161 and/or the second device 162 may communicate with one or more further devices not shown in FIG. 1F.

In some embodiments for Topoloty 1 with reference to FIG. 1B, the first device 161 may comprise the A-IoT device 121, and the second device 162 may comprise the BS 122. In some embodiments for Topoloty 2 with reference to FIG. 1C, the first device 161 may comprise the A-IoT device 131, and the second device 162 may comprise the intermediate node 132. In some embodiments for Topoloty 3A and Topoloty 3B with reference to FIG. 1D, the first device 161 may comprise the A-IoT device 141, and the second device 162 may comprise the BS 142 or the assisting node 143. In some embodiments for Topoloty 4 with reference to FIG. 1E, the first device 161 may comprise the A-IoT device 151, and the second device 162 may comprise the UE 152.

It is to be understood that the particular number of various communication devices and the particular number of various communication links as shown in FIG. 1F is for illustration purpose only without suggesting any limitations. The communications system 160 may include any suitable number of communication devices and any suitable number of communication links for implementing embodiments of the present disclosure. In addition, it should be appreciated that there may be various wireless as well as wireline communications (if needed) among all of the communication devices.

In recent years, IoT has attracted much attention in the wireless communication world. More “things” are expected to be interconnected to improve productivity efficiency and increase the comforts of life. Most of the existing wireless IoT devices may be powered by batteries that need to be replaced or recharged manually. The automation and digitalization of various industries open numbers of new markets requiring new IoT technologies of supporting battery-less devices with no energy storage capability or devices with energy storage that do not need to be replaced or recharged manually.

In the third generation partnership project (3GPP) , the technical report (TR) 22.840 is being developed to capture use cases, traffic scenarios, and device constraints of ambient power-enabled internet of things, and identify new potential service requirements as well as new key performance indicators (KPIs) . Moreover, the TR 38.848 provides a terminological and scoping framework for future discussions of A-IoT.

Continuous study for such kind of wireless IoT device, called A-IoT device, is still expected. During the RAN workgroup 2 (RAN2) discussions, it was agreed to study both the “4-step” and “2-step” contention based random access (CBRA) . “4-step” CBRA is also called “3-step” CBRA for the A-IoT system since “Msg4” is not always presence. For the CBRA, an important issue is handling the random access failure which is caused by, for example, message 1 (Msg1) collision, or a decoding problem because of interference or too far distance, etc. Then the re-access by the A-IoT device may need to be performed. On the other hand, RAN workgroup 1 (RAN1) has discussed an FDM scheme for random access. With the FDM scheme, multiple A-IoT devices may communicate with the reader on different frequencies in the same access time slot. As of now, there is no effective consideration regarding the re-access solution for the A-IoT system after random access failure, especially, based on the FDM scheme. Therefore, there is a need for an efficient re-access solution for the A-IoT system based on the FDM scheme.

Embodiments of the present disclosure provide a solution for re-access for the A-IoT system. In one aspect of the solution of the present disclosure, if a first device determines an access failure related to A-IoT communication to a second device, it determines a resource for an access occasion for re-access to the second device. Moreover, the first device performs re-access to the second device based on the resource.

By using the determined resource for re-access to the second device, this solution can facilitate the re-access to the second device on a suitable resource. In this way, it is possible to improve the flexibility and efficiency of communications in the A-IoT system.

FIG. 2 illustrates an example process flow 200 in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the processes 200 will be described with reference to FIG. 1F. It is to be understood that the steps and the order of the steps in FIG. 2 are merely for illustration, and not for limitation. It is to be understood that the process 200 may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2, if the first device 161 determines an access failure related to A-IoT communication to the second device 162, it determines (205) a resource (also referred to as re-access resource) for an access occasion for re-access (i.e., a re-access procedure) to the second device 162. For example, during a random access procedure, the first device 161 may determine the access failure happens if no confirmation message is received for Msg1 or a message 3 (Msg3) from the second device 162. Moreover, the first device 161 performs (210) re-access to the second device 162 based on the resource. The terms “re-access” and “re-access procedure” may be used interchangeably in some cases herein. The resource for re-access may comprise a time-domain resource and/or a frequency-domain resource.

In some embodiments, to improve the communication efficiency, FDM may be used. For example, three FDM cases may be considered for re-access. For the first FDM case of the above three FDM cases, in the same access occasion, there may be multiple frequency resources for re-access. In this case, for different frequencies of the multiple frequency resources, the time slots for re-access have the same length. FIG. 3A illustrates an example of the first FDM case in accordance with some example embodiments of the present disclosure. As shown in FIG. 3A, in the frequency-domain, there are 6 frequencies available to re-access, and the time slot lengths for different frequencies are the same.

For the second FDM case of the above three FDM cases, in the same access occasion, there may be multiple frequency resources for re-access. In this case, for different frequencies of the multiple frequency resources, the time slots for re-access have different lengths. For each frequency, there may be one time slot for re-access. FIG. 3B illustrates an example of the second FDM case in accordance with some example embodiments of the present disclosure. As shown in FIG. 3B, in the frequency-domain, there are 4 frequencies available to re-access, i.e., 40 kHz, 80 kHz, 160 kHz, and 320 kHz, and different frequencies correspond to different time slot lengths.

For the third FDM case of the above three FDM cases, in the same access occasion, there may be multiple frequency resources for re-access. In this case, for different frequencies of the multiple frequency resources, the time slots for re-access have different lengths. Additionally, For each frequency, there may be one or more time slots for re-access. FIG. 3C illustrates an example of the third FDM case in accordance with some example embodiments of the present disclosure. As shown in FIG. 3C, in the frequency-domain, there are 4 frequencies available to re-access, i.e., 40 kHz, 80 kHz, 160 kHz, and 320 kHz, and different frequencies correspond to different time slot lengths. Specifically, for each of the frequencies of 40 kHz, 80 kHz, 160 kHz, and 320 kHz, there are 8 time slots, 4 time slots, 2 time slots, and 1 time slot available to re-access respectively.

In some implementations, based on the above three FDM cases, an access trigger message for an access occasion may be assumed to be per-frequency (i.e., the access trigger message may be for a specific frequency) , or common (i.e., the access trigger message may be common for all frequencies) .

With respect to one or more of the above three FDM cases, the following determining approaches for the re-access resource may be considered.

In some embodiments, the first device 161 may obtain resource information (also referred to as a resource indication) indicating one or more resources for re-access (also referred to as one or more re-access resources) . The resource information may comprise frequency-domain resource information indicating one or more frequency-domain resources (for example, one or more frequencies) for re-access. For example, the one or more frequency-domain resources may comprise at least one frequency available to re-access of one or more frequencies for random access (i.e., for initial random access) , and/or a separate frequency for re-access (i.e. a frequency dedicated to re-access) .

Alternatively or additionally, the resource information may comprise time-domain resource information indicating one or more time-domain resources for re-access. For example, the time-domain resource information may indicate a parameter corresponding to a frequency-domain resource of the one or more frequency-domain resources, and the parameter may be used for determining one or more time slots for re-access. As an example implementation, the parameter may comprise a Q parameter, such as a Q parameter dedicated to re-access, also referred to as, Q_re-access. The Q parameter may be associated with the re-access frequency. For example, different Q parameter values may be indicated for different re-access frequencies.

In some embodiments, the first device 161 may select the resource for re-access from the one or more resources indicated in the resource information. The resource may be selected in a variety of ways.

As an example, the first device 161 may select the resource for re-access randomly. As an implementation, if there are provided multiple frequencies for re-access, the first device 161 may determine a frequency from the multiple frequencies available to re-access randomly. As an implementation, in determining the time-domain resource, the first device 161 may randomly select a time slot (i.e., an access slot) between 0 and 2^Qre-access-1. For instance, the first device 161 may determine an available time slot on each frequency available to re-access, and randomly determine a time-frequency resource in the selected access occasion. Accordingly, the first device may perform rea-access (for example, transmit a Msg1) on the selected resource for re-access.

As another example, the resource for re-access may be selected based on one or more of the following items: the capability of the first device 161, the device type of the first device 161, the energy status of the first device 161, or a priority indication of the one or more resources (for example, from the second device 162) . As an example implementation, the time-domain resource for re-access and/or the frequency-domain resource may be selected based on one or more of the above items. Accordingly, the first device may perform rea-access (for example, transmit a Msg1) on the selected resource for re-access.

Depending on the different approaches by which the resource information is obtained, detailed implementations at the first device 161 and the second device 162 may be different. In some implementations, referring back to FIG. 2, the second device 162 may transmit (215) the resource information to the first device 161. Alternatively or additionally, the first device 161 may obtain the resource information from the stored target resource information. These two kinds of approaches of obtaining the resource information will be discussed in detail later respectively.

In some embodiments, the above resource information may be contained in an access trigger message from the second device 162. In this case, when the second device 162 transmits an access trigger message to trigger an access occasion for an A-IoT device (for example, the first device 161) to access, the above resource information may be contained in the access trigger message. More details regarding the resource information and the re-access resource selection approach as discussed above also apply, and details of these discussions are omitted for brevity.

In some implementations, the one or more re-access resources may be indicated in each access trigger message or partial access trigger messages of multiple access trigger messages for multiple access occasions, for example, in a round. The first device 161 may determine a resource for re-access from the one or more re-access resources indicated in the resource information carried in the access trigger message. Then, re-access may be performed in the same round. For example, if the first device 161 determines that the access failure has happened, it may determine re-access resource whenever it receives the resource information in the access trigger message, and then use the determined re-access resource to re-access to the second device 162. Alternatively or additionally, if no re-access resource is indicated in an access trigger message for an access occasion, the first device 161 may fail to determine the re-access resource for the current occasion and need to wait for a further access trigger message for a further occasion.

In some implementations, the one or more resources indicated in the resource information may be associated with the access occasion (i.e., the current occasion) . The one or more re-access resources may be indicated in partial access trigger message (s) . In this case, the one or more re-access resources indicated in an access trigger message for an access occasion may only be used for this access occasion. For example, the access trigger message may comprise an explicit indication to indicate the one or more re-access resources indicated in the access trigger message may only be used for the access occasion associated with the access trigger message. Alternatively or additionally, the access trigger message for the access occasion may only indicate one or more frequency-domain resources to implicitely indicate that the one or more indicated frequency-domain resources may only be used for the access occasion associated with the access trigger message, and the time-domain resource for re-access may be selected within the access occasion. In other words, the access trigger message may indicate the one or more re-access resources in the access occasion corresponding to the access trigger message. In this case, if the first device 161 receives one or more re-access resources included in an access trigger message in a corresponding access occasion, and if the first device 161 determines that access failure has happened, it may determine the resource for re-access to the second device 162 in the corresponding access occasion from the one or more re-access resources indicated in the access trigger message in the corresponding access occasion. If no re-access resource is indicated, it means that no re-access resource on the current access occasion may be allowed.

In some embodiments, the above resource information may be contained in an adjust access trigger message to adjust one or more resources for initial random access (also referred to as one or more random access resources or one or more initial random access resources ) received from the second device 162. The one or more adjusted random access resources may comprise one or more adjusted time-domain random access resources (for example, based on an adjusted Q parameter) and/or one or more adjusted frequency-domain random access resources. In this case, the first device 161 may determine the re-access resource based on the received adjust access trigger message. More details regarding the resource information and the re-access resource selection approach as discussed above also apply, and details of these discussions are omitted for brevity.

In some implementations, the adjust access trigger message may only indicate one or more adjusted resources for initial random access. For example, an indication may be comprised in the adjust access trigger message or a paging message (also referred to as an initial trigger message) to indicate whether an A-IoT device (for example, the first device 161) that needs to perform re-access can determine re-access resource based on the one or more adjusted resources. In other words, an indication indicating whether the one or more adjusted resources are available to re-access may be comprised in the adjust access trigger message or the paging message. Accordingly, if the first device 161 is allowed to determine re-access resource based on the one or more adjusted resources (i.e., the one or more adjusted resources are available to re-access) , the first device 161 may initialize and determine the access resource based on the one or more adjusted resources for initial random access.

In some other implementations, the adjust access trigger message may indicate both one or more adjusted resources for initial random access (for example, for new access A-IoT device (s) ) and the one or more resources for re-access (for example, for re-access A-IoT device (s) ) . In this case, the first device 161 may determine re-access resource based on the one or more resources for re-access indicated in the adjust access trigger message. Only when the one or more resources for re-access are included in the adjust access trigger message, re-access may be allowed during the current access round.

In some embodiments, the first device 161 may store target resource information obtained from a target message (for example, a latest R2D message) , and then obtain the resource information indicating one or more resources for re-access based on the stored target resource information. For example, the first device 161 may store the information on one or more available frequencies or available Q parameter when the target message contains the indication of the one or more available frequencies or the available Q parameter. The target message may comprise a paging message or an access trigger message. The target resource information may indicate one or more of: one or more resources for random access (i.e., for initial random access) , or one or more resources for re-access. More details regarding the resource information and the re-access resource selection approach as discussed above also apply, and details of these discussions are omitted for brevity.

In the implementations where the target resource information indicates one or more resources for random access, the target message may further comprise an indication indicating whether the one or more resources for random access are available to re-access (that is, whether an A-IoT device is allowed to re-access in the same round (i.e., the same round in which the access failure occurs) ) . In this case, the first device 161 may store the target resource information obtained from the target message when the second device 162 indicates that the one or more resources for random access are available to re-access (i.e., an A-IoT device is allowed to re-access in the same round) . If the one or more resources for random access are available to re-access (that is, the first device 161 is allowed to re-access in the same round) , the first device 161 may determine the resource for re-access based on the one or more resources for random access indicated in the stored target resource information.

In the example embodiments where the target resource information further indicates one or more resources for re-access, the first device 161 may determine the resource for re-access based on the one or more resources for re-access indicated in the stored target resource information.

It is to be understood that the above embodiments for the obtaining approaches for the resource information indicating one or more resources for re-access are applicable to the above three FDM cases. Moreover, some other embodiments that are only applicable to the second FDM case and used to obtain the resource information indicating one or more resources for re-access will be discussed below.

In some embodiments, the above resource information may be contained in a message (for example, a dedicated message) received after an access trigger message for the access occasion (i. e, the current access occasion) and before an access trigger message for the next access occasion from the second device 162. In other words, the one or more re-access resources may be indicated by the dedicated message between two access trigger messages (i.e. the access trigger message for the current access occasion and the access trigger message for the next access occasion) . More details regarding the resource information and the re-access resource selection approach as discussed above also apply, and details of these discussions are omitted for brevity.

For example, after the second device 162 transmits the access trigger message to trigger the access occasion (i.e., the current access occasion) for the first device 161 to access, if the second device 162 determines that the first device 161 fails to access in the current access occasion, or after the second device 162 complete random access and data transmission for the first device 161 in the current access occasion, the second device 162 may transmit the dedicate message for re-access before transmitting the access trigger message for the next access occasion, when the second device 162 determines there are enough available resources for re-access. If the first device 161 determines the access failure has occurred in the current access occasion, it may then determine re-access resource in the same access occasion based on the resource information contained in the dedicated message.

In some implementaions, one or more time-domain resources and/or frequency-domain resources for re-access in the current access occasion may be indicated in the dedicate message for the first device 161 to determine the re-access resource. In the implementations where the resource information only indicates one or more time-domain resources, the first device 161 may select a time-domain resource for re-access from the one or more time-domain resources, and determine a frequency-domain resource for re-access as the same frequency-domain resource for random access for the access occasion. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) on the selected time-domain resource on the same frequency. In the implementations where the resource information indicates a time-domain resource and a frequency-domain resource, the first device 161 may determine the indicated time-domain resource and the indicated frequency-domain resource to be used for re-access. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) on the indicated time-domain resource on the associated frequency. In the implementations where the resource information indicates multiple time-domain together with the corresponding frequency-domain resource (s) , the first device 161 may randomly select a time-domain resource and corresponding frequency among all indicated multiple resources. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) in the randomly selected time-domain resource and corresponding frequency among all those indicated resources. If re-access on the first selected resource of the indicated multiple resources fails, the first device 161 may then re-access on other resources of the indicated resources one by one, for example, according to the order of the resource configuration, or the priority indicated for each resource, until re-access succeeds. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) on all indicated resources one by one.

In some embodiments, the above resource information may be contained in an access trigger message for the access occasion received from the second device 162. For example, when the second device 162 transmits the access trigger message to trigger an access occasion for the first device 161 to access, re-access resource (s) in the current access occasion may also included. More details regarding the resource information and the re-access resource selection approach as discussed above also apply, and details of these discussions are omitted for brevity.

In some implementations, in the time domain, the resource information (also referred to as the time-domain resource information) may comprise one or more time-domain offsets (i.e., one or more delay offsets) of one or more time-domain resources for re-access relative to a time-domain reference point. For example, the time-domain reference point may comprise one of the starting point of the Msg1 transmission (i.e., the Msg1 transmission for the failed random access) for the access occasion, an ending point of the Msg1 transmission, or a time when the first device 161 determines the access failure. Accordingly, when the access failure has occurred, the first device 161 may determine the time-domain resource for re-access based on the one or more time-domain resources determined based on the indicated one or more time-domain offsets.

In some implementations, in the frequency-domain, the resource information (also referred to as the frequency-domain resource information) may comprise one or more frequency-domain offsets (also referred to as one or more frequency offsets) of one or more frequency-domain resources for re-access relative to a frequency-domain reference point. For example, the frequency-domain reference point may comprise a frequency for random access for the access occasion. Accordingly, the first device 161 may determine the frequency-domain resource for re-access based on the one or more frequency-domain resources determined based on the indicated one or more frequency-domain offsets.

In the example implementations where a time-domain resource is indicated based on a time-domain offset, the first device 161 may determine the time-domain resource based on the indicated time-domain offset for re-accessing to the second device 162. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) after the corresponding delay offset with respect to the time-domain reference point.

In the example implementations where a time-domain resource is indicated based on a time-domain offset and a frequency-domain resource is indicated based on a frequency-domain offset, the first device 161 may determine the time-domain resource based on the indicated time-domain offset and the frequency-domain resource based on the indicated frequency-domain offset for re-accessing to the second device 162. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) after the corresponding delay offset with respect to the time-domain reference point on the frequency which has the corresponding frequency offset with respect to the frequency-domain reference point after the determination of access failure.

In the example implementations where multiple resources are indicated based on the one or more time-domain offsets and/or one or more corresponding frequency-domain offsets, the first device 161 may randomly select the resource for re-access from the multiple resources determined based on the one or more time-domain offsets and/or one or more corresponding frequency-domain offsets. In this case, the first device 161 may perform re-access (for example, transmit a Msg1) after the randomly selected delay offset with respect to the time-domain reference point and corresponding frequency which has the corresponding frequency offset with respect to the frequency-domain reference point after the determination of access failure. Alternatively or additionally, if re-access on the first selected resource of the indicated multiple resources fails, the first device 161 may then re-access on other resources of the indicated resources one by one, for example, according to the order of the resource configuration, or the priority indicated for each resource, until re-access succeeds.

According to some embodiments with reference to FIGS. 2 to 3C, it is allowed to support re-access for the A-IoT system well, and thus improve the flexibility and efficiency of communications in the A-IoT system

FIG. 4 illustrates an example of a device 400 that supports re-access for the A-IoT system in accordance with aspects of the present disclosure. The device 400 may be an example of a first device 161 or a second device 162 as described herein. The device 400 may support wireless communication with one or more devices in the A-IoT system. The device 400 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 402, a memory 404, a transceiver 406, and, optionally, an I/O controller 408. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 402, the memory 404, the transceiver 406, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 402 and the memory 404 coupled with the processor 402 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 402, instructions stored in the memory 404) .

For example, the processor 402 may support wireless communication at the device 400 in accordance with examples as disclosed herein. The processor 402 may be configured to operable to support a means for based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determining a resource for an access occasion for re-access to the second device; and a means for performing re-access to the second device based on the resource. The processor 402 may be configured to operable to support a means for transmitting, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access; or time-domain resource information indicating one or more time-domain resources for re-access

The processor 402 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 402 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 402. The processor 402 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 404) to cause the device 400 to perform various functions of the present disclosure.

The memory 404 may include random access memory (RAM) and read-only memory (ROM) . The memory 404 may store computer-readable, computer-executable code including instructions that, when executed by the processor 402 cause the device 400 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 402 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 404 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 408 may manage input and output signals for the device 400. The I/O controller 408 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 408 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 408 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 408 may be implemented as part of a processor, such as the processor 402. In some implementations, a user may interact with the device 400 via the I/O controller 408 or via hardware components controlled by the I/O controller 408.

In some implementations, the device 400 may include a single antenna 410. However, in some other implementations, the device 400 may have more than one antenna 410 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 406 may communicate bi-directionally, via the one or more antennas 410, wired, or wireless links as described herein. For example, the transceiver 406 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 406 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 410 for transmission, and to demodulate packets received from the one or more antennas 410. The transceiver 406 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 410 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 410 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 5 illustrates an example of a processor 500 that supports re-access for the A-IoT system in accordance with aspects of the present disclosure. The processor 500 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 500 may include a controller 502 configured to perform various operations in accordance with examples as described herein. The processor 500 may optionally include at least one memory 504, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 500 may optionally include one or more arithmetic-logic units (ALUs) 506. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 500 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 500) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 502 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 500 to cause the processor 500 to support various operations in accordance with examples as described herein. For example, the controller 502 may operate as a control unit of the processor 500, generating control signals that manage the operation of various components of the processor 500. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 502 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 504 and determine subsequent instruction (s) to be executed to cause the processor 500 to support various operations in accordance with examples as described herein. The controller 502 may be configured to track memory address of instructions associated with the memory 504. The controller 502 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 502 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 500 to cause the processor 500 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 502 may be configured to manage flow of data within the processor 500. The controller 502 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 500.

The memory 504 may include one or more caches (e.g., memory local to or included in the processor 500 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementations, the memory 504 may reside within or on a processor chipset (e.g., local to the processor 500) . In some other implementations, the memory 504 may reside external to the processor chipset (e.g., remote to the processor 500) .

The memory 504 may store computer-readable, computer-executable code including instructions that, when executed by the processor 500, cause the processor 500 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 502 and/or the processor 500 may be configured to execute computer-readable instructions stored in the memory 504 to cause the processor 500 to perform various functions. For example, the processor 500 and/or the controller 502 may be coupled with or to the memory 504, and the processor 500, the controller 502, and the memory 504 may be configured to perform various functions described herein. In some examples, the processor 500 may include multiple processors and the memory 504 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 506 may be configured to support various operations in accordance with examples as described herein. In some implementations, the one or more ALUs 506 may reside within or on a processor chipset (e.g., the processor 500) . In some other implementations, the one or more ALUs 506 may reside external to the processor chipset (e.g., the processor 500) . One or more ALUs 506 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 506 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 506 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 506 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 506 to handle conditional operations, comparisons, and bitwise operations.

The processor 500 may support wireless communication in accordance with examples as disclosed herein. The processor 500 may be configured to or operable to support a means for based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determining a resource for an access occasion for re-access to the second device; and a means for performing re-access to the second device based on the resource. The processor 500 may be configured to or operable to support a means for transmitting, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access; or time-domain resource information indicating one or more time-domain resources for re-access.

FIG. 6 illustrates a flowchart of a method 600 that supports re-access for the A-IoT system in accordance with aspects of the present disclosure. The operations of the method 600 may be implemented by a device or its components as described herein. For example, the operations of the method 600 may be performed by a first device 161 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 610, the method may include based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determining a resource for an access occasion for re-access to the second device. The operations of 610 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 610 may be performed by a first device 161 as described with reference to FIG. 1F.

At 620, the method may include performing re-access to the second device based on the resource. The operations of 620 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 620 may be performed by a first device 161 as described with reference to FIG. 1F.

FIG. 7 illustrates a flowchart of a method 700 that supports re-access for the A-IoT system in accordance with aspects of the present disclosure. The operations of the method 700 may be implemented by a device or its components as described herein. For example, the operations of the method 700 may be performed by a second device 162 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 710, the method may include transmitting, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following: frequency-domain resource information indicating one or more frequency-domain resources for re-access; or time-domain resource information indicating one or more time-domain resources for re-access. The operations of 710 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 710 may be performed by a second device 162 as described with reference to FIG. 1F.

It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

As used herein, including in the claims, an article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A first device comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the first device to:

based on determining an access failure related to ambient Internet of things (A-IoT) communication to a second device, determine a resource for an access occasion for re-access to the second device; and

perform re-access to the second device based on the resource.
The first device of claim 1, wherein determining the resource for re-access comprises:

obtaining resource information indicating one or more resources for re-access, the resource information comprising one or more of the following:

frequency-domain resource information indicating one or more frequency-domain resources for re-access; or

time-domain resource information indicating one or more time-domain resources for re-access.
The first device of claim 2, where one of the following:

the one or more frequency-domain resources comprise:

at least one frequency available to re-access of one or more frequencies for random access; or

a separate frequency for re-access; or

the time-domain resource information indicates a parameter corresponding to a frequency-domain resource of the one or more frequency-domain resources, the parameter being used for determining one or more time slots for re-access.
The first device of claim 2, wherein determining the resource for re-access comprises:

selecting the resource for re-access from the one or more resources indicated in the resource information, and

wherein the resource for re-access is selected randomly, or based on one or more of the following:

a capability of the first device;

a device type of the first device;

energy status of the first device; or

a priority indication of the one or more resources.
The first device of claim 2, wherein obtaining the resource information comprises:

obtaining the resource information based on an access trigger message received from the second device.
The first device of claim 5, wherein the access trigger message is an access trigger message for the access occasion, and the one or more resources indicated in the resource information are associated with the access occasion.
The first device of claim 2, wherein obtaining the resource information comprises:

obtaining the resource information based on an adjust access trigger message received from the second device.
The first device of claim 7, wherein the adjust access trigger message indicates one or more adjusted resources for initial random access, and wherein the at least one processor is further configured to cause the first device to:

obtain an indication indicating that the one or more adjusted resources are available to re-access, from the adjust access trigger message or a paging message.
The first device of claim 7, wherein the adjust access trigger message indicates one or more adjusted resources for initial random access and the one or more resources for re-access.
The first device of claim 2,

wherein the at least one processor is further configured to cause the first device to:

store target resource information obtained from a target message received from the second device, the target resource information indicating one or more of the following: one or more resources for random access, or the one or more resources for re-access; and

wherein obtaining the resource information comprises:

obtaining the resource information based on the stored target resource information.
The first device of claim 10,

wherein the target resource information indicates the one or more resources for random access, and the target message further comprises an indication indicating whether the one or more resources for random access are available to re-access, and

wherein determining the resource for re-access comprises:

based on determining that the one or more resources for random access are available to re-access, determining the resource for re-access based on the one or more resources for random access.
The first device of claim 10, wherein the target message comprises one of a paging message or an access trigger message.
The first device of claim 2, wherein obtaining the resource information comprises:

obtaining the resource information based on a message received from the second device after an access trigger message for the access occasion and before an access trigger message for a next access occasion.
The first device of claim 13, wherein the resource information indicates one or more time-domain resources, and determining the resource for re-access comprises:

selecting a time-domain resource for re-access from the one or more time-domain resources; and

determining a frequency-domain resource for re-access as a same frequency-domain resource for random access for the access occasion.
The first device of claim 2, wherein obtaining the resource information comprises:

obtaining the resource information based on an access trigger message for the access occasion received from the second device, and wherein one or more of the following:

the time-domain resource information comprises one or more time-domain offsets of the one or more time-domain resources for re-access relative to a time-domain reference point; or

the frequency-domain resource information comprises one or more frequency-domain offsets of one or more frequency-domain resources for re-access relative to a frequency-domain reference point.
The first device of claim 15, wherein one or more of the following:

the time-domain reference point comprises one of the following:

a starting point of message 1 transmission for the access occasion;

an ending point of the message 1 transmission; or

a time when the first device determines the access failure; or

the frequency-domain reference point comprises a frequency for random access for the access occasion.
A second device comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the first device to:

transmit, to a first device, resource information indicating one or more resources, wherein the one or more resources are used by the first device to re-access the second device for an access occasion when an access failure related to ambient Internet of things (A-IoT) communication to the second device occurs, and wherein the resource information comprises one or more of the following:

frequency-domain resource information indicating one or more frequency-domain resources for re-access; or

time-domain resource information indicating one or more time-domain resources for re-access.
The second device of claim 17, where one of the following:

the one or more frequency-domain resources comprise:

at least one frequency available to re-access of one or more frequencies for random access; or

a separate frequency for re-access; or

the time-domain resource information indicates a parameter corresponding to a frequency-domain resource of the one or more frequency-domain resources, the parameter being used for determining one or more time slots for re-access.
The second device of claim 17, wherein the resource information is transmitted in one of the following:

an access trigger message;

an adjust access trigger message;

a message after an access trigger message for the access occasion and before an access trigger message for a next access occasion.
The second device of claim 19, wherein one of the following:

the adjust access trigger message indicates one or more adjusted resources for initial random access, and wherein the one or more adjusted resources are indicated to be available to re-access in the adjust access trigger message or a paging message; or

the adjust access trigger message indicates one or more adjusted resources for initial random access and the one or more resources for re-access.