WO2024175222A1

WO2024175222A1 - Reader-based attachment procedure for passive terminal device

Info

Publication number: WO2024175222A1
Application number: PCT/EP2023/077593
Authority: WO
Inventors: Ahlem KHLASS; Muhammad Majid BUTT; Navin Hathiramani
Original assignee: Nokia Technologies Oy
Priority date: 2023-02-24
Filing date: 2023-10-05
Publication date: 2024-08-29

Abstract

Various techniques are provided for a method that may include receiving, by a terminal device from a network device, configuration information for the terminal device to transmit to or receive signals from at least one passive terminal device, wherein the configuration information configures the terminal device to perform at least one of transmit a signal to the at least one passive terminal device according to the configuration information, and receive, from the at least one passive terminal device, at least one signal each responsive to reception of the transmitted signal received at the at least one passive terminal device, and determining an association between the at least one passive terminal device and the terminal device based on received signal strength information of the at least one signal received at the terminal device.

Description

READER-BASED ATTACHMENT PROCEDURE FOR PASSIVE TERMINAL DEVICE

TECHNICAL FIELD

[0001] This description relates to wireless communications.

BACKGROUND

[0002] A communication system may be a facility that enables communication between two or more nodes or devices, such as fixed or mobile communication devices. Signals may be carried on wired or wireless carriers.

[0003] An example of a cellular communication system is an architecture that is being standardized by the 3^rd Generation Partnership Project (3GPP). A recent development in this field is often referred to as the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology. E-UTRA (evolved UMTS Terrestrial Radio Access) is the air interface of 3GPP's Long Term Evolution (LTE) upgrade path for mobile networks. In LTE, base stations or access points (APs), which are referred to as enhanced Node AP (eNBs), provide wireless access within a coverage area or cell. In LTE, mobile devices, or mobile stations are referred to as user equipments (UE). LTE has included a number of improvements or developments. Aspects of LTE are also continuing to improve.

[0004] 5G New Radio (NR) development is part of a continued mobile broadband evolution process to meet the requirements of 5G, similar to earlier evolution of 3G and 4G wireless networks. 5G is also targeted at the new emerging use cases in addition to mobile broadband. A goal of 5G is to provide significant improvement in wireless performance, which may include new levels of data rate, latency, reliability, and security. 5G NR may also scale to efficiently connect the massive Internet of Things (loT) and may offer new types of mission-critical services. For example, ultra-reliable and low-latency communications (URLLC) devices may require high reliability and very low latency. SUMMARY

[0005] According to an example embodiment, a method may include receiving, by a terminal device from a network device, configuration information for the terminal device to transmit to or receive signals from at least one passive terminal device, wherein the configuration information configures the terminal device to perform at least one of transmit a signal to the at least one passive terminal device according to the configuration information, and receive, from the at least one passive terminal device, at least one signal each responsive to reception of the transmitted signal received at the at least one passive terminal device, and determining an association between the at least one passive terminal device and the terminal device based on received signal strength information of the at least one signal received at the terminal device.

[0006] According to an example embodiment, a method may include transmitting, from a network device to at least one terminal device, configuration information to configure the at least one terminal device to transmit or receive signals to at least one passive terminal device and receiving, by the network device from the at least one terminal device, respective association information between the at least one passive terminal device and the at least one terminal device, wherein the respective association information is based on respective received signal strength information of at least one received signal received at the at least one terminal device, and the at least one received signal each is reflected or backscattered by the at least corresponding one passive terminal device in response to receiving a signal transmitted from the at least one terminal device.

[0007] The details of one or more examples of embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is a block diagram of a wireless network according to an example embodiment.

[0009] FIG. 2A is a diagram illustrating a network according to an example embodiment.

[0010] FIG. 2B is a diagram illustrating another network according to an example embodiment.

[0011] FIG. 2C is a diagram illustrating yet another network according to an example embodiment.

[0012] FIG. 2D is a diagram illustrating still another network according to an example embodiment.

[0013] FIG. 3 illustrates a signal flow diagram according to an example embodiment.

[0014] FIG. 4 illustrates another signal flow diagram according to an example embodiment.

[0015] FIG. 5 illustrates yet another signal flow diagram according to an example embodiment.

[0016] FIG. 6 is a block diagram illustrating a method of synchronous illumination for readers-edge passive terminal devices according to an example embodiment.

[0017] FIG. 7 is a block diagram of a method of operating a terminal device according to an example embodiment.

[0018] FIG. 8 is a block diagram of a method of operating a network device according to an example embodiment.

[0019] FIG. 9 is a block diagram of a wireless station or wireless node (e.g., AP, BS, gNB, RAN node, relay node, UE or user device, network node, network entity, DU, CU-CP, CU-CP, ... or other node) according to an example embodiment.

DETAILED DESCRIPTION

[0020] FIG. 1 is a block diagram of a wireless network 130 according to an example embodiment. In the wireless network 130 of FIG. 1, user devices 131, 132, 133 and 135, which may also be referred to as mobile stations (MSs) or user equipment (UEs), may be connected (and in communication) with a base station (BS) 134, which may also be referred to as an access point (AP), an enhanced Node B (eNB), a BS, next generation Node B (gNB), a next generation enhanced Node B (ng-eNB), or a network node. The terms user device and user equipment (UE) may be used interchangeably. A BS may also include or may be referred to as a RAN (radio access network) node, and may include a portion of a BS or a portion of a RAN node, such as (e.g., such as a centralized unit (CU) and/or a distributed unit (DU) in the case of a split BS). At least part of the functionalities of a BS (e.g., access point (AP), base station (BS) or (e)Node B (eNB), BS, RAN node) may also be carried out by any node, server or host which may be operably coupled to a transceiver, such as a remote radio head. BS (or AP) 134 provides wireless coverage within a cell 136, including to user devices (or UEs) 131, 132, 133 and 135. Although only four user devices (or UEs) are shown as being connected or attached to BS 134, any number of user devices may be provided. BS 134 is also connected to a core network 150 via a SI interface or NG interface 151. This is merely one simple example of a wireless network, and others may be used.

[0021] A base station (e.g., such as BS 134) is an example of a radio access network (RAN) node within a wireless network. A BS (or a RAN node) may be or may include (or may alternatively be referred to as), e.g., an access point (AP), a gNB, an eNB, or portion thereof (such as a centralized unit (CU) and/or a distributed unit (DU) in the case of a split BS or split gNB), or other network node. For example, a BS (or gNB) may include: a distributed unit (DU) network entity, such as a gNB-distributed unit (gNB-DU), and a centralized unit (CU) that may control multiple DUs. In some cases, for example, the centralized unit (CU) may be split or divided into: a control plane entity, such as a gNB- centralized (or central) unit-control plane (gNB-CU-CP), and an user plane entity, such as a gNB-centralized (or central) unit-user plane (gNB-CU-UP). For example, the CU subentities (gNB-CU-CP, gNB-CU-UP) may be provided as different logical entities or different software entities (e.g., as separate or distinct software entities, which communicate), which may be running or provided on the same hardware or server, in the cloud, etc., or may be provided on different hardware, systems or servers, e.g., physically separated or running on different systems, hardware or servers.

[0022] As noted, in a split configuration of a gNB/BS, the gNB functionality may be split into a DU and a CU. A distributed unit (DU) may provide or establish wireless communications with one or more UEs. Thus, a DUs may provide one or more cells, and may allow UEs to communicate with and/or establish a connection to the DU in order to receive wireless services, such as allowing the UE to send or receive data. A centralized (or central) unit (CU) may provide control functions and/or data-plane functions for one or more connected DUs, e.g., including control functions such as gNB control of transfer of user data, mobility control, radio access network sharing, positioning, session management etc., except those functions allocated exclusively to the DU. CU may control the operation of DUs (e.g., a CU communicates with one or more DUs) over a front-haul (Fs) interface. [0023] According to an illustrative example, in general, a BS node (e.g., BS, eNB, gNB, CU/DU, ... ) or a radio access network (RAN) may be part of a mobile telecommunication system. A RAN (radio access network) may include one or more BSs or RAN nodes that implement a radio access technology, e.g., to allow one or more UEs to have access to a network or core network. Thus, for example, the RAN (RAN nodes, such as BSs or gNBs) may reside between one or more user devices or UEs and a core network. According to an example embodiment, each RAN node (e.g., BS, eNB, gNB, CU/DU, ... ) or BS may provide one or more wireless communication services for one or more UEs or user devices, e.g., to allow the UEs to have wireless access to a network, via the RAN node. Each RAN node or BS may perform or provide wireless communication services, e.g., such as allowing UEs or user devices to establish a wireless connection to the RAN node, and sending data to and/or receiving data from one or more of the UEs. For example, after establishing a connection to a UE, a RAN node (e.g., BS, eNB, gNB, CU/DU, ... ) may forward data to the UE that is received from a network or the core network, and/or forward data received from the UE to the network or core network. RAN nodes (e.g., BS, eNB, gNB, CU/DU, ... ) may perform a wide variety of other wireless functions or services, e.g., such as broadcasting control information (e.g., such as system information) to UEs, paging UEs when there is data to be delivered to the UE, assisting in handover of a UE between cells, scheduling of resources for uplink data transmission from the UE(s) and downlink data transmission to UE(s), sending control information to configure one or more UEs, and the like. These are a few examples of one or more functions that a RAN node or BS may perform. A base station may also be DU (Distributed Unit) part of IAB (Integrated Access and Backhaul) node (a.k.a. a relay node). DU facilitates the access link connection(s) for an IAB node.

[0024] A user device (user terminal, user equipment (UE), mobile terminal, handheld wireless device, etc.) may refer to a portable computing device that includes wireless mobile communication devices operating either with or without a subscriber identification module (SIM) (which may be referred to as Universal SIM), including, but not limited to, the following types of devices: a mobile station (MS), a mobile phone, a cell phone, a smartphone, a personal digital assistant (PDA), a handset, a device using a wireless modem (alarm or measurement device, etc.), a laptop and/or touch screen computer, a tablet, a phablet, a game console, a notebook, a vehicle, a sensor, and a multimedia device, as examples, or any other wireless device. It should be appreciated that a user device may also be (or may include) a nearly exclusive uplink only device, of which an example is a camera or video camera loading images or video clips to a network. A user device may be also MT (Mobile Termination) part of IAB (Integrated Access and Backhaul) node (a.k.a. a relay node). MT facilitates the backhaul connection for an IAB node.

[0025] In LTE (as an illustrative example), core network 150 may be referred to as Evolved Packet Core (EPC), which may include a mobility management entity (MME) which may handle or assist with mobility /handover of user devices between BSs, one or more gateways that may forward data and control signals between the BSs and packet data networks or the Internet, and other control functions or blocks. Other types of wireless networks, such as 5G (which may be referred to as New Radio (NR)), 5G- Advanced, 6G, and the like may also include a core network (e.g., which may be referred to as 5GC in 5G/NR).

[0026] In addition, by way of illustrative example, the various example embodiments or techniques described herein may be applied to various types of user devices or data service types, or may apply to user devices that may have multiple applications running thereon that may be of different data service types. New Radio (5G) and 6G development may support a number of different applications or a number of different data service types, such as for example: machine type communications (MTC), enhanced machine type communication (eMTC), massive MTC (mMTC), Internet of Things (loT), and/or narrowband loT user devices, enhanced mobile broadband (eMBB), and ultra-reliable and low-latency communications (URLLC). Many of these new 5G (NR) and 6G-related applications may require generally higher performance than previous wireless networks.

[0027] loT may refer to an ever-growing group of objects that may have Internet or network connectivity, so that these objects may send information to and receive information from other network devices. For example, many sensor type applications or devices may monitor a physical condition or a status and may send a report to a server or other network device, e.g., when an event occurs. Machine Type Communications (MTC, or Machine to Machine communications) may, for example, be characterized by fully automatic data generation, exchange, processing and actuation among intelligent machines, with or without intervention of humans. Enhanced mobile broadband (eMBB) may support much higher data rates than currently available in LTE.

[0028] Ultra-reliable and low-latency communications (URLLC) is a new data service type, or new usage scenario, which may be supported for New Radio (5G) and 6G systems. This enables emerging new applications and services, such as industrial automations, autonomous driving, vehicular safety, e-health services, and so on. 3 GPP targets in providing connectivity with reliability corresponding to block error rate (BLER) of 10-5 and up to 1 ms U-Plane (user/data plane) latency, by way of illustrative example. Thus, for example, URLLC user devices/UEs may require a significantly lower block error rate than other types of user devices/UEs as well as low latency (with or without requirement for simultaneous high reliability). Thus, for example, a URLLC UE (or URLLC application on a UE) may require much shorter latency, as compared to an eMBB UE (or an eMBB application running on a UE).

[0029] The various example embodiments may be applied to a wide variety of wireless technologies or wireless networks, such as LTE, LTE- A, 5G (New Radio (NR)), 6G, cmWave, and/or mmWave band networks, loT, MTC, eMTC, mMTC, eMBB, URLLC, etc., or any other wireless network or wireless technology. These example networks, technologies or data service types are provided only as illustrative examples.

[0030] Energy harvesting enabled communication services may be used in various vertical industries including logistics, manufacture, transportation, energy industry, and the like. Passive terminal devices (sometimes called passive loT devices and/or tags) may include terminal devices without batteries and/or terminal devices with limited energy storage capability (e.g., using a capacitor). Enabling passive terminal devices, in both public and private networks, may benefit the 5G ecosystem.

[0031] Some areas of consideration associated with passive terminal devices may include operation under extreme environmental conditions (e.g., high pressure, extremely high/low temperature, humid environment, vibration, and the like), ultra-low complexity(cost), very small terminal size/form factor (e.g., thickness of mm), maintenance- free and longer life cycle, etc., are strongly required.

[0032] The passive terminal device segment may provide significantly lower power consumption and lower complexity compared to existing 3 GPP terminal (e.g., loT) technologies. Battery less passive terminal device may have advantages in reducing power consumption, device cost and maintenance cost.

[0033] However, there would be different use cases for passive terminal device, and KPIs on data rates, coverage, etc., would vary in different use case. Larger coverage or higher data rate may be required in some use cases, which would mean higher device power consumption. For example, reflection amplifier may be required in passive terminal device to achieve better coverage. This may lead to higher power consumption, (e.g., several hundred micro-watts). While the energy harvested from ambient may not be sufficient for some harvesting method, it would be very useful from reduced maintenance cost perspective, if a coin battery may be used to support such passive terminal device to stand several years. Hence, the implementations may include both battery-less devices and devices with energy storage capability.

[0034] Energy harvesting enabled communication services may be configured to use backscattering technologies. Radio-frequency identification (RFID) solutions may use with backscattering technology. Passive terminal devices may use 3 GPP technology to enhance coverage for backscattering RFID solutions as well as introduce new solutions with advanced features like harvesting energy from the dedicated source or ambient energy source and spending energy efficiently for passive terminal device data transmissions.

[0035] A problem with existing energy harvesting enabled communication services may be that BS (e.g., BS 134) may not always be used as an illuminator for backscattering due to a limited link budget for the BS. In addition, the BS may not be used in an initial attachment procedure because the BS may not be the most efficient source to provide power to the passive terminal device(s). Further, using the BS in an in an initial attachment procedure may create interference to UEs being served by the BS. For example, if the backscattered signal associated with a passive terminal device at a cell edge is to be received and correctly decoded by the BS, the power transmitted by the BS to illuminate the passive terminal device must be very high. Therefore, the power transmitted by the BS to illuminate the passive terminal device will likely interfere with all other communications (e.g., UEs) operating at the same frequency.

[0036] Prior solutions may deploy multiple illuminators as well as receivers (or readers) depending on a density of the passive terminal device(s). These illuminators and receivers could be 5G terminals that have all the characteristics of 5G UE and may communicate with the BS. The nearby deployed illuminator and receiver may minimize the power required for illumination. For example, an illuminator would only cover proximate passive terminal device(s) (e.g., a small range due to limited maximum transmission power of UE’s). The 5G terminals may transmit at a power that may have a smaller impact in terms of interference to the UEs and passive terminal device(s) in the small range.

[0037] The illuminators and/or receivers may be fixed and powered by an AC/DC power supply or may be mobile battery powered based on use cases and/or system requirements. In some cases, when passive terminal device(s) no longer exist around some of the illuminators and/or as receivers, the passive terminal device(s) may be deactivated by the system or opportunistically illuminated and/or received by mobile 5G terminals. When a backscattering passive terminal device is admitted, multiple illuminators and/or receivers may be used based on density of the passive terminal device(s). In order to achieve goals associated with energy harvesting enabled communication services to use 3 GPP technology, several problems should be solved. For example, the problem may include how to ensure reduced signaling overhead, efficient resource usage, minimized interference level at the network for each association that may be for a short duration and/or repeats in time.

[0038] Example implementations may solve these, and additional problems caused by passive terminal device association through 5G NR mechanisms. Example implementations may describe new signaling between the BS, illuminator, receiver, and passive terminal device(s). Example implementations may avoid direct signaling between a UE and a BS by using distributed readers to complete the attachment procedure.

[0039] FIG. 2A is a diagram illustrating a network according to an example embodiment. As shown in FIG. 2A, the network (e.g., a cellular network) includes the BS 134 and a passive terminal device 205 (e.g., a passive loT device, a tag, and the like). The BS 134 may be configured to transmit a carrier wave (CW) 210 and the passive terminal device 205 may be configured to reflect the CW 210 as a backscattered signal 215. For deployment of the passive terminal device 205 in the cellular network, the BS 134 may serve as a reader similar to, for example, a RFID reader. The BS 134 may be configured to provide the CW 210 as an RF energy source and control signaling to the passive terminal device 205 via the CW 210. The passive terminal device 205 may be configured to transmit information to the BS 134 via the reflected or backscattered signal 215. In this example implementation, the passive terminal device 205 may be supported without UE assistance. In this example implementation, the BS 134 may be configured to support full duplex operation (e.g., transmitting the CW 210 and receiving the reflected or backscattered signal 215 simultaneously).

[0040] FIG. 2B is a diagram illustrating another network according to an example embodiment. As shown in FIG. 2B, the network (e.g., a cellular network) includes the BS 134, the passive terminal device 205 (e.g., a passive loT device, a tag, and the like), and the UE 131. The UE 131 may be configured to transmit the CW 210 and the passive terminal device 205 may be configured to reflect the CW 210 as the reflected or backscattered signal 215. The BS 134 may be serving the UE 131 via cellular signal 225. In addition, the passive terminal device 205 may be configured to communicate data to the BS 134 via the UE 131 using a data flow signal 220-1, 220-2.

[0041] In some scenarios, passive terminal device coverage may not be always available via a BS (e.g., smart home devices). Therefore, in an example implementation, the UE 131 may serve as the reader. In other words, the UE 131 may be configured to provide the CW 210 and to receive the reflected or backscattered signal 215 from the passive terminal device 205. In this implementation, the passive terminal device 205 may not be directly linked to the network. Therefore, the UE 131 may be configured to relay data via the data flow signal 220-1, 220-2. The data may be obtained from the passive terminal device 205. In addition, the passive terminal device 205 may be registered with the network vial the UE 313. In other words, the UE 131 may be a relay node between the BS 134 (and the network) and the passive terminal device 205. In this example implementation, the UE 131 may be configured to support full duplex operation (e.g., transmitting the CW 210 and receiving the reflected or backscattered signal 215 substantially simultaneously).

[0042] FIG. 2C is a diagram illustrating yet another network according to an example embodiment. As shown in FIG. 2C, the network (e.g., a cellular network) includes the BS 134, the passive terminal device 205 (e.g., a passive loT device, a tag, and the like), and the UE 131. The BS 134 may be configured to transmit the CW 210 and the passive terminal device 205 may be configured to reflect the CW 210 as the reflected or backscattered signal 215. The UE 131 may be configured to receive the reflected or backscattered signal 215. The BS 134 may be serving the UE 131 via cellular signal 225. In addition, the passive terminal device 205 may be configured to communicate data to the BS 134 via the UE 131 using a data flow signal 220-1, 220-2. In addition, the BS 134 may generate an interference signal 230 that interferes with the UE 131.

[0043] FIG. 2D is a diagram illustrating still another network according to an example embodiment. As shown in FIG. 2D, the network (e.g., a cellular network) includes the BS 134, the passive terminal device 205 (e.g., a passive loT device, a tag, and the like), and the UE 131. The UE 131 may be configured to transmit the CW 210 and the passive terminal device 205 may be configured to reflect the CW 210 as the reflected or backscattered signal 215. The BS 134 may be configured to receive the reflected or backscattered signal 215. The BS 134 may be serving the UE 131 via cellular signal 225. In addition, the passive terminal device 205 may be configured to communicate data to the BS 134 using a data flow signal 220. In addition, the BS 134 may generate an interference signal 230 that interferes with the UE 131.

[0044] FIG. 2C and 2D may illustrate a UE assisted passive terminal device usage scenario. As shown, in this example implementation, the UE 131 may be configured to assist the communication between passive loT device and a BS. In FIG. 2C, the UE 131 may be configured to obtain data from the passive terminal device 205, and the data may be relayed to the BS 134 (e.g., the network). In FIG. 2D, the BS 134 may be configured to obtain data from the passive terminal device 205 and the UE 131 may be configured as a nearby RF energy source.

[0045] In the example implementations illustrated in FIGS. 2C and 2D, the UE 131 and/or the BS 134 may be configured as the transmitter for CW and/or command, and/or the BS 134 may be configured as the receiver of reflected or backscattered signal from the passive terminal device 205. However, in an example implementation, the UE 131 and/or the BS 134 may not be both transmitter and receiver simultaneously. Therefore, full duplex operation may not be required by either the BS 134 and/or the UE 131. Accordingly, the example implementations illustrated in FIGS. 2C and 2D may have a reduced complexity.

[0046] UE assisted passive terminal device communication may provide coverage benefits in addition to implementation complexity reduction. The UE to passive terminal device distance may be shorter than the passive terminal device to BS distance. Therefore, the round trip pathloss (e.g., from carrier wave transmitter to reflection signal receiver) may be reduced. Some data/signaling exchange between the BS and the UE may be implemented, and a link between the UE and the BS may be more robust compared with a passive terminal device to BS link. Accordingly, better coverage may be expected with UE assistance.

[0047] Example implementations may include data transfer between the passive terminal device and passive terminal application. The passive terminal application may be configured to record the reader (e.g., a UE or a RAN) which may transfer data for the passive terminal device. When the reader is changed (e.g., when the passive terminal device is moving), the passive terminal application may be updated with a new reader. In this implementation, to minimize processing complexity, the passive terminal device may not access the 5G core network in an update operation.

[0048] Example implementations may include the UE or RAN helping a passive terminal device to access a 5G core network (e.g., register to the AMF). The passive terminal device may not need to support NAS protocol stack which may help support ultralow cost and ultra-low power passive terminal devices. Moreover, the AMF may be configured to manage the corresponding reader to a passive terminal device and may not need to support separated NAS connections with each passive terminal device. In this implementation, the 5G core network may support passive terminal services. For example, the 5G core network may help to authenticate a passive terminal device, perform mobility management to the passive terminal device (e.g., provides location information of Passive loT device), manage the readers within the operator’s network, and select the reader to help establishing communication with the passive terminal device to avoid interference among readers.

[0049] Example implementations describe a reader-based association for passive terminal devices. The reader-based association may use a BS assistance as needed. The association decision may be made by the readers. In an example implementation, the decision may be based on the perceived link quality, by comparing the backscattered received signal’s RSRP to the RSRP threshold pre-configured by the BS. If backscattered received signal’s RSRP is greater than a threshold (e.g., RSRP threshold), the passive terminal device may be associated with the reader. Otherwise, the passive terminal device may not be associated with the reader (e.g., to later associate with a more suitable reader). If the RSRP threshold is not configured by the BS, a reader may be configured to rely on their device sensitivity. Should each reader perform autonomous association with passive terminal devices, there could be passive terminal devices which are associated with several readers.

[0050] In an example implementation the readers may be configured to report the association decisions to the BS in order to refine reader association decisions. The reporting may be triggered, for example, periodically, following a pre-configured timer for reporting. The reporting may be triggered, for example, in response to a BS request (e.g., the BS may schedule a common signal to request readers to report their association decisions). The reporting may be triggered, for example, based on a list of passive terminal devices that are being associated. The reporting may be triggered, for example, in response to an event at the reader (e.g., load exceeds a certain level which would need the BS involvement to efficiently distribute the load among readers.

[0051] Objectives associated with a BS refinement procedure may include coordinating between illuminators/readers in case of synchronized signal broadcast and hence strengthening the received signal at particular passive terminal device at edge, ensuring efficient load balancing between readers based on the passive terminal device ID decoded from the backscattering signals distributing query occasions to avoid high level of interference and collisions for reader - passive terminal device queries, deciding on the validity of the attachment, and/or the like.

[0052] In an example implementation, the BS may be configured to provide an association update message to all readers which may also contain an updated configuration. Readers may be configured to apply the new association decision refined by the BS and the new configuration, if received.

[0053] According to an example implementation, passive terminal devices (e.g., passive loT devices, tags, and the like) may be configured to communicate with the readers via backscattering. In some scenarios the passive terminal devices may have limited processing capabilities. For example, passive terminal devices may include a microprocessor and may have the capability to synchronize based on a given signal. The passive terminal devices may not have a full 3 GPP protocol stack. In other words, passive terminal devices may support limited parts of the LI stack. The passive terminal devices may not have the capability of performing RSRP measurements.

[0054] According to an example implementation, readers may be 5G UEs enhanced with capabilities to illuminate passive terminal devices and to decode backscattered signals received from the passive terminal devices. Readers and exciters may be two different 3 GPP devices, coordinating on illumination signal and backscattering signal reception. Readers and/or exciters may be switched ON/OFF based on a duty cycle (e.g., as configured by the BS for active transmission and reception occasions and sleep periods). Exciters may illuminate with respect to a maximum Tx power configured by the BS. The BS may be configured as a default reader and/or illuminator. Readers may be configured to derive the approximate position of the passive terminal devices.

[0055] The BS may be configured to configure dedicated 3GPP illuminators or illuminator and/or reader to broadcast energy. This configuration may include one or more of the following parameters, maximum transmit power to be used for illumination, which could be common for all illuminators or specific to each illuminator with a general purpose to reduce the overall interference in the system, RSRP threshold, if configured, is considered for passive terminal device association, duty cycle by which the readers/exciters are activated for receiving backscattering signals and/or transmitting illumination signals and de-activated (i.e., entering sleep mode with no Tx/Rx) for an efficient energy consumption, time offset on when a transmission should be initiated for scenarios where multiple illuminators broadcast energy simultaneously. One use case of passive terminal devices is obtaining their position. If the position is known synchronous illumination may be further fine-tuned via providing offsets for different illuminators.

[0056] FIG. 3 illustrates a signal flow diagram according to an example embodiment. As shown in FIG. 3, a network may include a passive terminal device (PTD) 305, a PTD 310, a reader/exciter 315, a reader/exciter 320, and the BS 134. In an example implementation, the BS 134 may communicate with the reader/exciter 315 and the reader/exciter 320 using a cellular standard. The BS 134 may be a combination of devices. For example, the BS 134 may represent a BS and a core network device (or entity), the BS 134 may represent a BS and a control device (or entity), the BS 134 may represent a base station onboard a satellite, a satellite as a repeater and a terrestrial base station, and any other similar combination of network devices. A single device and/or the combination of devices may sometimes be referred to as a device, a system, and/or the like. The reader/exciter 315 and the reader/exciter 320 may be a user device, a terminal device, a user terminal, a mobile device, a stationary device, an internet of things (loT) device, any wirelessly (or cellular) connected device, and/or the like.

[0057] The BS 134 may communicate (e.g., wirelessly communicate) a message (block 322A) that is received by the reader/exciter 320. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 322B) that is received by the reader/exciter 315. In this implementation, the message is generated by the BS 134 and communicated to the reader/exciter 315 and the reader/exciter 320. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by both the reader/exciter 315 and the reader/exciter 320. The message may include a reader-based passive terminal device configuration. The reader-based passive terminal device configuration may be associated with a monostatic deployment. For example, the readerbased passive terminal device configuration may include at least one of maximum transmit power to be used for illumination, which could be common for all illuminators or specific to each illuminator with a general purpose to reduce the overall interference in the system, RSRP threshold, if configured, is considered for passive terminal device association, duty cycle by which the readers/exciters are activated for receiving backscattering signals and/or transmitting illumination signals and de-activated (i.e., entering sleep mode with no Tx/Rx) for an efficient energy consumption, time offset on when a transmission should be initiated for scenarios where multiple illuminators broadcast energy simultaneously, and/or the like. In response to receiving the message, the reader/exciter 315 and the reader/exciter 320 may be configured for reader-based passive terminal device association based on the readerbased passive terminal device configuration.

[0058] The reader/exciter 320 may generate and transmit (block 324A) an illumination signal that is received by the PTD 310. The reader/exciter 320 may generate and transmit (block 324B) an illumination signal that is received by the PTD 305. In an example implementation one illumination signal is transmitted (e.g., broadcast) by the reader/exciter 320 and received by both the PTD 305 and the PTD 310. In response to receiving the illumination signal, the PTD 305 may generate and transmit (block 326A) a backscattering signal. The backscattering signal may be received by the reader/exciter 315. The backscattering signal may include an identification (ID) associated with the PTD 305 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 305 may generate and transmit (block 326B) a backscattering signal. The backscattering signal may be received by the reader/exciter 320. In an example implementation one backscattering signal is generated and transmitted or reflected by the PTD 305 and received by both the reader/exciter 315 and the reader/exciter 320.

[0059] In response to receiving the illumination signal, the PTD 310 may generate and transmit or reflect (block 328 A) a backscattering signal. The backscattering signal may be received by the reader/exciter 315. The backscattering signal may include an identification (ID) associated with the PTD 310 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 310 may generate and transmit (block 328B) a backscattering signal. The backscattering signal may be received by the reader/exciter 320. The backscattering signal may include an identification (ID) associated with the PTD 310 (sometimes called a tagID). In an example implementation one backscattering signal is generated and transmitted or reflected by the PTD 310 and received by both the reader/exciter 315 and the reader/exciter 320.

[0060] In response to receiving the backscattering signals from PTD 305 and/or PTD 310, the reader/exciter 315 may perform a passive terminal device association (block 330). For example, the PTD 305 may be associated with the reader/exciter 315. In response to receiving the backscattering signals from PTD 305 and/or PTD 310, the reader/exciter 320 may perform a passive terminal device association (block 332). For example, the PTD 310 may be associated with the reader/exciter 320. Each reader/exciter may be configured to makes the decision to associate a PTD based on received RSRP. In an example implementation, the RSRP threshold, if configured, may be lowered to ensure passive terminal device association to at least one reader. In another example, the RSRP threshold, if configured, may be made high to reduce simultaneous association. In another example, if RSRP threshold is not configured, the association decision may be made based on the device sensitivity to detect signal reception.

[0061] After performing the passive terminal device association (block 330), the reader/exciter 315 may communicate (e.g., wirelessly communicate) a message (block 334A) that is received by the reader/exciter 320. The reader/exciter 315 may communicate (e.g., wirelessly communicate) a message (block 334B) that is received by the BS 134. In the example implementation of FIG. 3, the reader/exciter 315 reports to the reader/exciter 320 and the BS 134. However, although not shown, the reader/exciter 320 may report to the reader/exciter 315 and the BS 134. In addition, the reader/exciter 315 may report to the reader/exciter 320 and then the reader/exciter 320 may report to the BS 134, or the reader/exciter 320 may report to the reader/exciter 315 and then the reader/exciter 315 may report to the BS 134. The message may include passive terminal device association information. For example, the passive terminal device association information may include identification (ID) associated with the PTD 305 and/or PTD 310 (sometimes called a tagID). In an example implementation, the passive terminal device association information may be communicated periodically and/or in response to a trigger. For example, the reader/exciter 320 may be configured to report the association decisions to the BS in order to refine reader/exciter association decisions. The reporting may be triggered, for example, periodically, following a pre-configured timer for reporting. The reporting may be triggered, for example, in response to a BS request (e.g., the BS may schedule a common signal to request readers to report their association decisions). The reporting may be triggered, for example, based on a list of passive terminal devices that are being associated. The reporting may be triggered, for example, in response to an event at the reader (e.g., load exceeds a certain level which would need the BS involvement to efficiently distribute the load among readers.

[0062] In response to receiving the passive terminal device association information, the BS 134 may perform an attachment refinement operation (block 336). After performing the attachment refinement operation (block 336), the BS 134 may communicate (e.g., wirelessly communicate) a message (block 338A) that is received by the reader/exciter 320. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 338B) that is received by the reader/exciter 315. In this implementation, the message is generated by the BS 134 and communicated to the reader/exciter 315 and the reader/exciter 320. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by both the reader/exciter 315 and the reader/exciter 320. The message may include updated association and reader/exciter configuration information that was generated in block 336. In an example implementation, the association update information may include the identification (ID) associated with the PTD 305 and/or PTD 310 (sometimes called a tagID) to associate. In an example implementation, the new configuration could include an updated duty cycle configuration to ensure a better coordination between available readers/exciters. The reader/exciter 315 and the reader/exciter 320 may employ this duty cycle to ensure there are no collisions when performing queries to PTDs.

[0063] FIG. 4 illustrates another signal flow diagram according to an example embodiment. As shown in FIG. 4, a network may include a passive terminal device (PTD) 405, a PTD 410, an exciter 415, an exciter 420, a reader 425, a reader 430, and the BS 134. In an example implementation, the BS 134 may communicate with the exciter 415, the exciter 420, the reader 425, and the reader 430 using a cellular standard. The BS 134 may be a combination of devices. For example, the BS 134 may represent a BS and a core network device (or entity), the BS 134 may represent a BS and a control device (or entity), the BS 134 may represent a base station onboard a satellite, a satellite as a repeater and a terrestrial base station, and any other similar combination of network devices. A single device and/or the combination of devices may sometimes be referred to as a device, a system, and/or the like. The exciter 415, the exciter 420, the reader 425, and/or the reader 430 may be a user device, a terminal device, a user terminal, a mobile device, a stationary device, an internet of things (loT) device, any wirelessly (or cellular) connected device, and/or the like.

[0064] The BS 134 may communicate (e.g., wirelessly communicate) a message (block 432A) that is received by the reader 430. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 432B) that is received by the reader 425. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 432C) that is received by the exciter 420. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 432C) that is received by the exciter 415. In this implementation, the message is generated by the BS 134 and communicated to the exciter 415, the exciter 420, the reader 425, and/or the reader 430. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by the exciter 415, the exciter 420, the reader 425, and/or the reader 430. The message may include a reader-based passive terminal device configuration. The reader-based passive terminal device configuration may be associated with a reader based bistatic deployment. For example, the reader-based passive terminal device configuration may include at least one of maximum transmit power to be used for illumination, which could be common for all illuminators or specific to each illuminator with a general purpose to reduce the overall interference in the system, RSRP threshold, if configured, is considered for passive terminal device association, duty cycle by which the readers/exciters are activated for receiving backscattering signals and/or transmitting illumination signals and de-activated (i.e., entering sleep mode with no Tx/Rx) for an efficient energy consumption, time offset on when a transmission should be initiated for scenarios where multiple illuminators broadcast energy simultaneously, and/or the like. In response to receiving the message, exciter 415, the exciter 420, the reader 425, and/or the reader 430 may be configured for reader-based passive terminal device association based on the reader-based passive terminal device configuration.

[0065] The exciter 420 may generate and transmit (block 434A) an illumination signal that is received by the PTD 410. The exciter 420 may generate and transmit (block 434B) an illumination signal that is received by the PTD 405. In an example implementation one illumination signal is transmitted (e.g., broadcast) by the exciter 420 and received by both the PTD 405 and the PTD 410. The exciter 415 may generate and transmit (block 436A) an illumination signal that is received by the PTD 410. The exciter 415 may generate and transmit (block 434B) an illumination signal that is received by the PTD 405. In an example implementation one illumination signal is transmitted (e.g., broadcast) by the exciter 415 and received by both the PTD 405 and the PTD 410.

[0066] In response to receiving the illumination signal, the PTD 405 may generate and transmit (block 438 A) a backscattering signal. The backscattering signal may be received by the reader 425. The backscattering signal may include an identification (ID) associated with the PTD 405 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 405 may generate and transmit (block 438B) a backscattering signal. The backscattering signal may be received by the reader 430. The backscattering signal may include an identification (ID) associated with the PTD 405 (sometimes called a tagID). In an example implementation one backscattering signal is generated and transmitted or reflected by the PTD 405 and received by both the reader 425 and the reader 430.

[0067] In response to receiving the illumination signal, the PTD 410 may generate and transmit (block 440A) a backscattering signal. The backscattering signal may be received by the reader 425. The backscattering signal may include an identification (ID) associated with the PTD 410 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 410 may generate and transmit or reflect (block 440B) a backscattering signal. The backscattering signal may be received by the reader 430. The backscattering signal may include an identification (ID) associated with the PTD 410 (sometimes called a tagID). In an example implementation one backscattering signal is generated and transmitted by the PTD 410 and received by both the reader 425 and the reader 430.

[0068] In response to receiving the backscattering signals from PTD 405 and/or PTD 410, the reader 425 may perform a passive terminal device association (block 442). For example, the PTD 405 may be associated with the reader 425. In response to receiving the backscattering signals from PTD 405 and/or PTD 410, the reader 430 may perform a passive terminal device association (block 444). For example, the PTD 410 may be associated with the reader 430. Reader 425 and reader 430 each may be configured to makes the decision to associate a PTD based on received RSRP. In an example implementation, the RSRP threshold, if configured, may be low to ensure passive terminal device association to at least one reader. In another example, the RSRP threshold, if configured, may be high to reduce simultaneous association. In another example, if RSRP threshold is not configured, the association decision may be made based on the device sensitivity.

[0069] After performing the passive terminal device association (block 442), the reader 425 may communicate (e.g., wirelessly communicate) a message (block 446) that is received by the BS 134. The reader 430 may communicate (e.g., wirelessly communicate) a message (block 448) that is received by the BS 134. In the example implementation of FIG. 4, the reader 425 and the reader 430 reports to the BS 134. However, although not shown, the reader 425 may report to the reader 430 and the reader 430 may report to the BS 134. Alternatively (or in addition), the reader 430 may report to the reader 425 and the reader 425 may report to the BS 134. The message may include passive terminal device association information. For example, the passive terminal device association information may include identification (ID) associated with the PTD 405 and/or PTD 410 (sometimes called a tagID). In an example implementation, the passive terminal device association information may be communicated periodically and/or in response to a trigger. For example, the reader 425 and/or the reader 430 may be configured to report the association decisions to the BS 134 in order to refine reader association decisions. The reporting may be triggered, for example, periodically, following a pre-configured timer for reporting. The reporting may be triggered, for example, in response to a BS 134 request (e.g., the BS 134 may schedule a common signal to request readers to report their association decisions). The reporting may be triggered, for example, based on a list of passive terminal devices that are being associated. The reporting may be triggered, for example, in response to an event at the reader (e.g., load exceeds a certain level which would need the BS 134 involvement to efficiently distribute the load among readers.

[0070] In response to receiving the passive terminal device association information, the BS 134 may perform an attachment refinement operation (block 450). After performing the attachment refinement operation (block 450), the BS 134 may communicate (e.g., wirelessly communicate) a message (block 452A) that is received by the reader 430. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 452B) that is received by the reader 425. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 452C) that is received by the exciter 420. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 452D) that is received by the exciter 415.

[0071] In this implementation, the message is generated by the BS 134 and communicated to the exciter 415, the exciter 420, the reader 425, and/or the reader 430. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by the exciter 415, the exciter 420, the reader 425, and/or the reader 430. The message may include updated association and reader/exciter configuration information that was generated in block 450. In an example implementation, the association update information may include the identification (ID) associated with the PTD 405 and/or PTD 410 (sometimes called a tagID) to associate. In an example implementation, the new configuration could include an updated duty cycle configuration to ensure a better coordination between available readers/exciters. The reader 425 and the reader 430 may employ this duty cycle to ensure there are no collisions when performing queries to PTDs.

[0072] FIG. 5 illustrates yet another signal flow diagram according to an example embodiment. As shown in FIG. 5, a network may include a passive terminal device (PTD) 505, a PTD 510, an exciter 515, an exciter 520, a reader 525, a reader 530, and the BS 134. In an example implementation, the BS 134 may communicate with the exciter 515, the exciter 520, the reader 525, and the reader 530 using a cellular standard. The BS 134 may be a combination of devices. For example, the BS 134 may represent a BS and a core network device (or entity), the BS 134 may represent a BS and a control device (or entity), the BS 134 may represent a base station onboard a satellite, a satellite as a repeater and a terrestrial base station, and any other similar combination of network devices. A single device and/or the combination of devices may sometimes be referred to as a device, a system, and/or the like. The exciter 515, the exciter 520, the reader 525, and/or the reader 530 may be a user device, a terminal device, a user terminal, a mobile device, a stationary device, an internet of things (loT) device, any wirelessly (or cellular) connected device, and/or the like.

[0073] The BS 134 may communicate (e.g., wirelessly communicate) a message (block 532A) that is received by the reader 530. The BS 134 may communicate

(e.g., wirelessly communicate) a message (block 532B) that is received by the reader 525. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 532C) that is received by the exciter 520. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 532C) that is received by the exciter 515. In this implementation, the message is generated by the BS 134 and communicated to the exciter 515, the exciter 520, the reader 525, and/or the reader 530. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by the exciter 515, the exciter 520, the reader 525, and/or the reader 530. The message may include a reader-based passive terminal device configuration. The reader-based passive terminal device configuration may be associated with a reader based bistatic deployment. For example, the reader-based passive terminal device configuration may include at least one of maximum transmit power to be used for illumination, which could be common for all illuminators or specific to each illuminator with a general purpose to reduce the overall interference in the system, RSRP threshold, if configured, is considered for passive terminal device association, duty cycle by which the readers/exciters are activated for receiving backscattering signals and/or transmitting illumination signals and de-activated (i.e., entering sleep mode with no Tx/Rx) for an efficient energy consumption, time offset on when a transmission should be initiated for scenarios where multiple illuminators broadcast energy simultaneously, and/or the like. In response to receiving the message, exciter 515, the exciter 520, the reader 525, and/or the reader 530 may be configured for reader-based passive terminal device association based on the reader-based passive terminal device configuration.

[0074] The exciter 520 may generate and transmit (block 534A) an illumination signal that is received by the PTD 510. The exciter 520 may generate and transmit (block 534B) an illumination signal that is received by the PTD 505. In an example implementation one illumination signal is transmitted (e.g., broadcast) by the exciter 520 and received by both the PTD 505 and the PTD 510. The exciter 515 may generate and transmit (block 536A) an illumination signal that is received by the PTD 510. The exciter 515 may generate and transmit (block 534B) an illumination signal that is received by the PTD 505. In an example implementation one illumination signal is transmitted (e.g., broadcast) by the exciter 515 and received by both the PTD 505 and the PTD 510.

[0075] In response to receiving the illumination signal, the PTD 505 may generate and transmit (block 538A) a backscattering signal. The backscattering signal may be received by the reader 525. The backscattering signal may include an identification (ID) associated with the PTD 505 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 505 may generate and transmit (block 538B) a backscattering signal. The backscattering signal may be received by the reader 530. The backscattering signal may include an identification (ID) associated with the PTD 505 (sometimes called a tagID). In an example implementation one backscattering signal is generated and transmitted by the PTD 505 and received by both the reader 525 and the reader 530.

[0076] In response to receiving the illumination signal, the PTD 510 may generate and transmit (block 540A) a backscattering signal. The backscattering signal may be received by the reader 525. The backscattering signal may include an identification (ID) associated with the PTD 510 (sometimes called a tagID). In response to receiving the illumination signal, the PTD 510 may generate and transmit (block 540B) a backscattering signal. The backscattering signal may be received by the reader 530. The backscattering signal may include an identification (ID) associated with the PTD 510 (sometimes called a tagID). In an example implementation one backscattering signal is generated and transmitted by the PTD 510 and received by both the reader 525 and the reader 530. [0077] In response to receiving the backscattering signals from PTD 505 and/or PTD 510, the reader 525 may perform a passive terminal device association (block 542). For example, the PTD 505 may be associated with the reader 525. In response to receiving the backscattering signals from PTD 505 and/or PTD 510, the reader 530 may perform a passive terminal device association (block 544). For example, the PTD 510 may be associated with the reader 530. Reader 525 and reader 530 each may be configured to makes the decision to associate a PTD based on received RSRP. In an example implementation, the RSRP threshold, if configured, may be lowered to ensure passive terminal device association to at least one reader. In another example, the RSRP threshold, if configured, may be raised to reduce simultaneous association. In another example, if RSRP threshold is not configured, the association decision may be made based on the device sensitivity.

[0078] After performing the passive terminal device association (block 542), the reader 525 may communicate (e.g., wirelessly communicate) a message (block 546) that is received by the BS 134. The reader 530 may communicate (e.g., wirelessly communicate) a message (block 548) that is received by the BS 134. In the example implementation of FIG. 5, the reader 525 and the reader 530 reports to the BS 134. However, although not shown, the reader 525 may report to the reader 530 and the reader 530 may report to the BS 134. Alternatively (or in addition), the reader 530 may report to the reader 525 and the reader 525 may report to the BS 134. The message may include passive terminal device association information. For example, the passive terminal device association information may include identification (ID) associated with the PTD 505 and/or PTD 510 (sometimes called a tagID). In an example implementation, the passive terminal device association information may be communicated periodically and/or in response to a trigger. For example, the reader 525 and/or the reader 530 may be configured to report the association decisions to the BS 134 in order to refine reader association decisions. The reporting may be triggered, for example, periodically, following a pre-configured timer for reporting. The reporting may be triggered, for example, in response to a BS 134 request (e.g., the BS 134 may schedule a common signal to request readers to report their association decisions). The reporting may be triggered, for example, based on a list of passive terminal devices that are being associated. The reporting may be triggered, for example, in response to an event at the reader (e.g., load exceeds a certain level which would need the BS 134 involvement to efficiently distribute the load among readers.

[0079] In response to receiving the passive terminal device association information, the BS 134 may perform an attachment refinement operation (block 550). In an example implementation, the attachment refinement operation may be configured to increase connectivity of the PTDs which are not able to backscatter signal with good RSRP (e.g., greater than a threshold) to any of the available readers and hence not able to be associated to any reader. However, the backscattered signal may be above reader sensitivity. To help these PTDs (sometimes called edge PTDs or edge tags), in addition to the illuminator ID, the readers provide the perceived SINK, towards all associated PTDs. The BS 134 may then identify the PTDs that are potentially in poor radio conditions (e.g., experiencing low SINK) and send an association information to the corresponding exciters to enable synchronous illumination. Therefore, the overall received signal at the PTDs may be improved. PTDs may collect more energy from more than one illuminator to send a backscattering signal with higher SINK, to their associated readers.

[0080] After performing the attachment refinement operation (block 550), the BS 134 may communicate (e.g., wirelessly communicate) a message (block 552A) that is received by the reader 530. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 552B) that is received by the reader 525. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 552C) that is received by the exciter 520. The BS 134 may communicate (e.g., wirelessly communicate) a message (block 552D) that is received by the exciter 515.

[0081] In this implementation, the message is generated by the BS 134 and communicated to the exciter 515, the exciter 520, the reader 525, and/or the reader 530. In an example implementation one message is communicated (e.g., broadcast) by the BS 134 and received by the exciter 515, the exciter 520, the reader 525, and/or the reader 530. The message may include updated association and reader/exciter configuration information that was generated in block 550. In an example implementation, the association update information may include the identification (ID) associated with the PTD 505 and/or PTD 510 (sometimes called a tagID) to associate. In an example implementation, the new configuration could include an updated duty cycle configuration to ensure a better coordination between available readers/exciters. The reader 525 and the reader 530 may employ this duty cycle to ensure there are no collisions when performing queries to PTDs. [0082] Further, a synchronous illumination may be enabled (block 554) on the exciter 515 and/or the exciter 520. Synchronous illumination may include two or more exciters illuminating at substantially the same time in order to increase energy (e.g., used for backscattering) at a PTD. Synchronous illumination may only be performed for selected exciters when needed by edge PTDs. Enabling synchronous illumination for all exciters blindly may raise the overall system interference. After enabling synchronous illumination, the attachment is performed as described above and the readers report their attached tags ID to the BS 134 substantially immediately or by following the reporting period configured by the BS 134 in order to ensure that tags are associated with only one reader (and multiple exciters) as required by design target.

[0083] FIG. 6 is a block diagram illustrating a method of synchronous illumination for readers-edge PTDs according to an example embodiment. As shown in FIG. 6, in block S605 one or more devices may communicate PTD ID, SINK at readers, exciter ID, etc., to a network device (e.g., a BS). For example, a PTD may generate a backscatter signal that is received by a reader. The backscatter signal may include PTD ID, exciter ID, and the like. The reader may measure an SINR associated with the backscatter signal. The reader may communicate the PTD ID, the SINR, the exciter ID, and/or the like to the network device.

[0084] In block S610 the network device (e.g., a BS) may receive information from all PTDs. The information may be received via a reader. The information may include the PTD ID, the SINR, the exciter ID, and/or the like.

[0085] In block S615 the network device may determine if the SINR is greater than a threshold on at least one reader. For example, the network device may receive the information from a plurality of readers and the information may be associated with a plurality of PTDs. The network device may determine if the SINR is greater than the threshold on at least one of the plurality of readers. If the SINR is greater than the threshold on at least one of the plurality of readers processing continues to step S625. Otherwise, processing continues at step S620.

[0086] In block S620 the network device may determine if more than one reader reporting a PTD. If more than one reader reporting a PTD processing continues to step S635. Otherwise, processing continues at step S630.

[0087] In block S625 the network device generates a configuration to attach the PTD(s) with the reader with the largest SINK and save corresponding exciter ID. The network device may communicate the configuration to an exciter causing the new configuration to be implemented.

[0088] In block S630 The network determines that no attachment is available for the PTD. The network then waits for the next attachment cycle.

[0089] In block S610 all readers are attached (e.g., in a list of readers) if reporting readers report different illuminators. The exciters are time synchronized for generation of the illumination signal.

[0090] Example 1. FIG. 7 is a block diagram of a method of operating a terminal device according to an example embodiment. As shown in FIG. 7, in step S705 receive, by a terminal device from a network device, configuration information for the terminal device to transmit to or receive signals from at least one passive terminal device, wherein the configuration information configures the terminal device to perform at least one of (1) in step S710 transmit a signal to the at least one passive terminal device according to the configuration information, and (2) in step S715 receive, from the at least one passive terminal device, at least one signal each responsive to reception of the transmitted signal received at the at least one passive terminal device. In step S720 determine an association between the at least one passive terminal device and the terminal device based on received signal strength information of the at least one signal received at the terminal device.

[0091] Example 2. The method of Example 1, wherein the received signal strength information may include a received signal power level.

[0092] Example 3. The method of Example 1, wherein the terminal device may include one of an exciter, a reader, or a co-located exciter and reader.

[0093] Example 4. The method of Example 1, wherein the determining of the association between the at least one passive terminal device and the terminal device may be based on a forwarded signal based on a received passive terminal device signal.

[0094] Example 5. The method of Example 4, wherein the forwarded signal may be received from another terminal device.

[0095] Example 6. The method of Example 4, wherein the forwarded signal may be received via a network node.

[0096] Example 7. The method of Example 1, wherein the configuration information may include one or more of: maximum transmission power level, a duty cycle configuration, and a threshold value of the at least one received signal.

[0097] Example 8. The method of Example 7, wherein the terminal device may be further caused to determine the association between the at least one passive terminal device and the terminal device based on the threshold value.

[0098] Example 9. The method of Example 7 or 8, wherein the terminal device may be further caused to associate the terminal device with the at least one passive terminal device by comparing the received signal strength information with the threshold value.

[0099] Example 10. The method of any of Example 1 to Example 9, wherein the terminal device may be further caused to report to or update the network device, the association between the at least one passive terminal device and the terminal device based on the received signal strength information exceeding a threshold value.

[0100] Example 11. The method of Example 10, wherein reporting the association information between the at least one passive terminal device and the terminal device may be triggered based on at least one of a pre-configured timer for reporting, in response to a network request, and a pre-defined event at the terminal device for reporting.

[0101] Example 12. The method of Example 10, wherein the terminal device may be further caused to receive, from the network device, an association update message between the at least one passive terminal device and the terminal device.

[0102] Example 13. The method of Example 12, wherein the terminal device may be further caused to associate the terminal device with the at least one passive terminal device based on the association update message content.

[0103] Example 14. The method of Example 13, wherein the update message content may be part of or associated with a configuration information update.

[0104] Example 15. The method of Example 13, wherein the terminal device may be further caused to enable synchronous illumination with another terminal device, wherein the synchronous illumination includes synchronizing with the another terminal device, the transmission time of the signal to the at least one passive terminal device.

[0105] Example 16. The method of Example 4, wherein the terminal device may be further caused to determine the association between the at least one passive terminal device and the terminal device based on a device sensitivity of the terminal device.

[0106] Example 17. FIG. 8 is a block diagram of a method of operating a network device according to an example embodiment. As shown in FIG. 8, in step S805 transmit, to at least one terminal device, configuration information to configure the at least one terminal device to transmit or receive signals to at least one passive terminal device. In step S810 receive from the at least one terminal device, respective association information between the at least one passive terminal device and the at least one terminal device, wherein the respective association information is based on respective received signal strength information of at least one received signal received at the at least one terminal device, and the at least one received signal each is reflected or backscattered by the at least corresponding one passive terminal device in response to receiving a signal transmitted from the at least one terminal device.

[0107] Example 18. The method of Example 17, wherein the network device may be further caused to transmit to a specific one terminal device, an update of the association information in response to a change of association between the specific one terminal with a specific one passive terminal device.

[0108] Example 19. The method of Example 17, wherein the received reflected or backscattered signal strength information may include a received signal power level.

[0109] Example 20. The method of Example 17, wherein the at least one terminal device may include one of an exciter, a reader, or a co-located exciter and reader.

[0110] Example 21. The method of Example 18, wherein the configuration information may include the at least one passive terminal device identification, a time offset, a duty cycle configuration, a threshold value of the received reflected or backscattered signal, a synchronous illumination enabled indicator, and a maximum transmit power value of the at least one user terminal device.

[0111] Example 22. The method of Example 21 , wherein the synchronous illumination enabled indicator may indicate to enable synchronous illumination for the at least one passive terminal device based on a received power associated with the at least one passive terminal device being less than the threshold value.

[0112] Example 23. The method of Example 17, wherein the network device may be further caused to receive from one or more terminal device association information of one or more passive terminal device wherein the association information includes one or more passive terminal device identification and corresponding reflection signal received power. [0113] Example 24. The method of Example 23, wherein the network device may be further caused to determine whether one of the reflection signal received power is greater than a received power threshold value and in response to determining one of the reflection signal received power is greater than a received power threshold value, generate an association update message that comprises updated configurations to be applied by a specific terminal device.

[0114] Example 25. The method of Example 23, wherein the network device may be further caused to determine whether two or more terminal device identifications are received and in response to determining the two or more terminal device identifications are received, generate the association update message to enable synchronous illumination to each of the two or more terminal devices wherein the synchronous illumination is based on the association information and the received signal power of one or more passive terminal device.

[0115] Example 26. A method may include any combination of one or more of Example 1 to Example 25.

[0116] Example 27. A non-transitory computer-readable storage medium comprising instructions stored thereon that, when executed by at least one processor, are configured to cause a computing system to perform the method of any of Examples 1-26.

[0117] Example 28. An apparatus comprising means for performing the method of any of Examples 1-26.

[0118] Example 29. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform the method of any of Examples 1 -26.

[0119] FIG. 9 is a block diagram of a wireless station 900 or wireless node or network node 900 according to an example embodiment. The wireless node or wireless station or network node 900 may include, e.g., one or more of an AP, BS, gNB, RAN node, relay node, UE or user device, network node, network entity, DU, CU-CP, CU-UP, ... or other node according to an example embodiment.

[0120] The wireless station 900 may include, for example, one or more (e.g., two as shown in FIG. 9) radio frequency (RF) or wireless transceivers 902A, 902B, where each wireless transceiver includes a transmitter to transmit signals and a receiver to receive signals. The wireless station also includes a processor or control unit/entity (controller) 904 to execute instructions or software and control transmission and receptions of signals, and a memory 906 to store data and/or instructions.

[0121] Processor 904 may also make decisions or determinations, generate frames, packets or messages for transmission, decode received frames or messages for further processing, and other tasks or functions described herein. Processor 904, which may be a baseband processor, for example, may generate messages, packets, frames or other signals for transmission via wireless transceiver 902 (902A or 902B). Processor 904 may control transmission of signals or messages over a wireless network, and may control the reception of signals or messages, etc., via a wireless network (e.g., after being down-converted by wireless transceiver 902, for example). Processor 904 may be programmable and capable of executing software or other instructions stored in memory or on other computer media to perform the various tasks and functions described above, such as one or more of the tasks or methods described above. Processor 904 may be (or may include), for example, hardware, programmable logic, a programmable processor that executes software or firmware, and/or any combination of these. Using other terminology, processor 904 and transceiver 902 together may be considered as a wireless transmitter/receiver system, for example.

[0122] In addition, referring to FIG. 9, a controller (or processor) 908 may execute software and instructions, and may provide overall control for the station 900, and may provide control for other systems not shown in FIG. 9, such as controlling input/output devices (e.g., display, keypad), and/or may execute software for one or more applications that may be provided on wireless station 900, such as, for example, an email program, audio/video applications, a word processor, a Voice over IP application, or other application or software.

[0123] In addition, a storage medium may be provided that includes stored instructions, which when executed by a controller or processor may result in the processor 904, or other controller or processor, performing one or more of the functions or tasks described above.

[0124] According to another example embodiment, RF or wireless transceiver(s) 902A/902B may receive signals or data and/or transmit or send signals or data. Processor 904 (and possibly transceivers 902A/902B) may control the RF or wireless transceiver 902A or 902B to receive, send, broadcast or transmit signals or data.

[0125] The example embodiments are not, however, restricted to the system that is given as an example, but a person skilled in the art may apply the solution to other communication systems. Another example of a suitable communications system is the 5G system. It is assumed that network architecture in 5G will be quite similar to that of the LTE-advanced. 5G is likely to use multiple input - multiple output (MIMO) antennas, many more base stations or nodes than the LTE (a so-called small cell concept), including macro sites operating in co-operation with smaller stations and perhaps also employing a variety of radio technologies for better coverage and enhanced data rates. Another example of a suitable communications system is the 6G system. It is assumed that network architecture in 6G will be similar to that of the 5G.

[0126] It should be appreciated that future networks will most probably utilize network functions virtualization (NFV) which is a network architecture concept that proposes virtualizing network node functions into “building blocks” or entities that may be operationally connected or linked together to provide services. A virtualized network function (VNF) may comprise one or more virtual machines running computer program codes using standard or general type servers instead of customized hardware. Cloud computing or data storage may also be utilized. In radio communications this may mean node operations may be carried out, at least partly, in a server, host or node operationally coupled to a remote radio head. It is also possible that node operations will be distributed among a plurality of servers, nodes or hosts. It should also be understood that the distribution of labor between core network operations and base station operations may differ from that of the LTE or even be non-existent.

[0127] Example embodiments of the various techniques described herein may be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. Example embodiments may be implemented as a computer program product, i.e., a computer program tangibly embodied in an information carrier, e.g., in a machine-readable storage device or in a propagated signal, for execution by, or to control the operation of, a data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. Embodiments may also be provided on a computer readable medium or computer readable storage medium, which may be a non-transitory medium. Embodiments of the various techniques may also include embodiments provided via transitory signals or media, and/or programs and/or software embodiments that are downloadable via the Internet or other network(s), either wired networks and/or wireless networks. In addition, embodiments may be provided via machine type communications (MTC), and also via an Internet of Things (IOT).

[0128] The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. Depending on the processing power needed, the computer program may be executed in a single electronic digital computer or it may be distributed amongst a number of computers.

[0129] Furthermore, example embodiments of the various techniques described herein may use a cyber-physical system (CPS) (a system of collaborating computational elements controlling physical entities). CPS may enable the embodiment and exploitation of massive amounts of interconnected ICT devices (sensors, actuators, processors microcontrollers, ...) embedded in physical objects at different locations. Mobile cyber physical systems, in which the physical system in question has inherent mobility, are a subcategory of cyberphysical systems. Examples of mobile physical systems include mobile robotics and electronics transported by humans or animals. The rise in popularity of smartphones has increased interest in the area of mobile cyber-physical systems. Therefore, various embodiments of techniques described herein may be provided via one or more of these technologies.

[0130] A computer program, such as the computer program(s) described above, may be written in any form of programming language, including compiled or interpreted languages, and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit or part of it suitable for use in a computing environment. A computer program may be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.

[0131] Method steps may be performed by one or more programmable processors executing a computer program or computer program portions to perform functions by operating on input data and generating output. Method steps also may be performed by, and an apparatus may be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

[0132] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer, chip, or chipset. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. Elements of a computer may include at least one processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer also may include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0133] To provide for interaction with a user, embodiments may be implemented on a computer having a display device, e.g., a cathode ray tube (CRT) or liquid crystal display (LCD) monitor, for displaying information to the user and a user interface, such as a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user may provide input to the computer. Other kinds of devices may be used to provide for interaction with a user as well; for example, feedback provided to the user may be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user may be received in any form, including acoustic, speech, or tactile input.

[0134] Example embodiments may be implemented in a computing system that includes a back-end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front-end component, e.g., a client computer having a graphical user interface or a Web browser through which a user may interact with an embodiment, or any combination of such back-end, middleware, or front-end components. Components may be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (LAN) and a wide area network (WAN), e.g., the Internet.

[0135] While certain features of the described embodiments have been illustrated as described herein, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the various embodiments.

Claims

WHAT IS CLAIMED IS:

1. A terminal device, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal device at least to: receive, from a network device, configuration information for the terminal device to transmit to or receive signals from at least one passive terminal device, wherein the configuration information configures the terminal device to perform at least one of: transmit a signal to the at least one passive terminal device according to the configuration information, and receive, from the at least one passive terminal device, at least one signal each responsive to reception of the transmitted signal received at the at least one passive terminal device; and determine an association between the at least one passive terminal device and the terminal device based on received signal strength information of the at least one signal received at the terminal device.

2. The terminal device of claim 1 , wherein the received signal strength information comprises a received signal power level.

3. The terminal device of claim 1, wherein the terminal device comprises one of: an exciter; a reader; or a co-located exciter and reader.

4. The terminal device of claim 1, wherein the determining of the association between the at least one passive terminal device and the terminal device is based on a forwarded signal based on a received passive terminal device signal.

5. The terminal device of claim 4, wherein the forwarded signal is received from another terminal device.

6. The terminal device of claim 4, wherein the forwarded signal is received via a network node.

7. The terminal device of claim 1 , wherein the configuration information comprises one or more of: maximum transmission power level, a duty cycle configuration, and a threshold value of the at least one received signal.

8. The terminal device of claim 7, wherein the terminal device is caused to: determine the association between the at least one passive terminal device and the terminal device based on the threshold value.

9. The terminal device of claim 7 or 8, wherein the terminal device is caused to: associate the terminal device with the at least one passive terminal device by comparing the received signal strength information with the threshold value.

10. The terminal device of any of claim 3 to claim 9, wherein the terminal device is caused to: report to or update the network device, the association between the at least one passive terminal device and the terminal device based on the received signal strength information exceeding a threshold value.

11. The terminal device of claim 10, wherein reporting the association information between the at least one passive terminal device and the terminal device is triggered based on at least one of: a pre-configured timer for reporting; in response to a network request; and a pre-defined event at the terminal device for reporting.

12. The terminal device of claim 10, wherein the terminal device is caused to: receive, from the network device, an association update message between the at least one passive terminal device and the terminal device.

13. The terminal device of claim 12, wherein the terminal device is caused to: associate the terminal device with the at least one passive terminal device based on the association update message content.

14. The terminal device of claim 13, wherein the update message content is part of or associated with a configuration information update.

15. The terminal device of claim 13, wherein the terminal device is caused to: enable synchronous illumination with another terminal device, wherein the synchronous illumination includes synchronizing with the another terminal device, the transmission time of the signal to the at least one passive terminal device.

16. The terminal device of claim 4, wherein the terminal device is caused to: determine the association between the at least one passive terminal device and the terminal device based on a device sensitivity of the terminal device.

17. A network device, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the network device at least to: transmit, to at least one terminal device, configuration information to configure the at least one terminal device to transmit or receive signals to at least one passive terminal device; and receive, from the at least one terminal device, respective association information between the at least one passive terminal device and the at least one terminal device, wherein the respective association information is based on respective received signal strength information of at least one received signal received at the at least one terminal device, and the at least one received signal each is reflected or backscattered by the at least corresponding one passive terminal device in response to receiving a signal transmitted from the at least one terminal device.

18. The network device of claim 17, wherein the network device is caused to: transmit to a specific one terminal device, an update of the association information in response to a change of association between the specific one terminal with a specific one passive terminal device.

19. The network device of claim 17, wherein the received reflected or backscattered signal strength information comprises a received signal power level.

20. The network device of claim 17, wherein the at least one terminal device comprises one of: an exciter; a reader; or a co-located exciter and reader.

21. The network device of claim 18, wherein the configuration information includes the at least one passive terminal device identification, a time offset, a duty cycle configuration, a threshold value of the received reflected or backscattered signal, a synchronous illumination enabled indicator, and a maximum transmit power value of the at least one user terminal device.

22. The network device of claim 21, wherein the synchronous illumination enabled indicator indicates to enable synchronous illumination for the at least one passive terminal device based on a received power associated with the at least one passive terminal device being less than the threshold value.

23. The network device of claim 17, wherein the network device is caused to: receive from one or more terminal device association information of one or more passive terminal device wherein the association information includes one or more passive terminal device identification and corresponding reflection signal received power.

24. The network device of claim 23, wherein the network device is caused to: determine whether one of the reflection signal received power is greater than a received power threshold value; and in response to determining one of the reflection signal received power is greater than a received power threshold value, generate an association update message that comprises updated configurations to be applied by a specific terminal device.

25. The network device of claim 23, wherein the network device is caused to: determine whether two or more terminal device identifications are received; and in response to determining the two or more terminal device identifications are received, generate the association update message to enable synchronous illumination to each of the two or more terminal devices wherein the synchronous illumination is based on the association information and the received signal power of one or more passive terminal device.

26. An apparatus comprising means for performing the steps of any of the terminal device of claims 1-16.

27. An apparatus comprising means for performing the steps of any of the network device of claims 17-25.

28. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform the steps of any of the terminal device of claims 1-16.

29. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform the steps of any of the network device of claims 17-25.