WO2024050111A1

WO2024050111A1 - Wireless power transfer with active-coordination-sets

Info

Publication number: WO2024050111A1
Application number: PCT/US2023/031887
Authority: WO
Inventors: Jibing Wang; Erik Stauffer
Original assignee: Google Llc
Priority date: 2022-09-02
Filing date: 2023-09-01
Publication date: 2024-03-07

Abstract

A system and method of wireless power transfer. The method also includes performing a wireless power transfer measurement operation to identify a second set of base stations (121, 122, and 132) for a second active-coordination-set (ACS) 120, the second ACS 120 transferring power between the second ACS 120 and a user equipment (UE) 110, and the second set of base stations (121, 122, and 132) includes a second base station 121. The method further includes transmitting a first message, to the UE 110, indicating a set of frequencies and a set of time slots for power transfer from the second ACS 120 to the UE 110. The method further includes transmitting a second message, to the second base station 121 via a first ACS 130, indicating the second set of base stations (121, 122, and 132) in the second ACS 120.

Description

WIRELESS POWER TRANSFER WITH ACTIVE-COORDINATION- SETS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63/403,588, filed 02 September 2022, the disclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates generally to power transfer, and more particularly, to systems and methods of wireless power transfer with active-coordination-sets.

BACKGROUND

[0003] A user equipment (UE) may communicate data with one or more wireless communication networks (such as 5^th Generation (5G) cellular networks and/or wireless local area networks). As the UE communicates data with a wireless communication network (e.g., transmits and/or receives data) and performs various other operations, the UE depletes internal power sources (such as a battery) to maintain communications. The UE may charge the internal power source in various ways. For example, the UE may be directly plugged in a power source (e.g., a wall charger or outlet) via a wire/cable. In another example, the UE is charged using near-field charging techniques (e.g., using an induction charging pad/stand). Both of these charging methods are physically limiting for the wireless UE and there are opportunities to expand charging options to increase UE mobility while charging.

SUMMARY

[0004] The following presents a simplified summary of some aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description discussed below.

[0005] As discussed above, a UE may communicate data with a wireless communication network. The UE may communicate data via an active-coordination set (ACS). An ACS is set of base stations determined (e.g., identified, selected, etc.) by the UE to perform joint transmission and/or reception (joint communication) of user plane data and control plane messages/messaging between the UE and the base stations in the ACS. An ACS used for joint communication of data is referred to herein as an ACS-DT. A coordinating base station of the ACS-DT coordinates joint transmission and/or reception for the UE. [0006] As the UE 110 communicates wirelessly with the ACS-DT, the UE discharges power stored in internal power sources (such as a battery) to maintain communications. The UE mayrecharge the internal power source in various ways. However, charging pads/stands or wires/cables limit the mobility of the UE while the UE is charging.

[0007] The present disclosure addresses the above-noted and other deficiencies by leveraging the use of an ACS for wireless power transfer (e.g., wireless charging using far-field wireless power transfer) to the UE 110. A separate ACS for wireless power transfer (WPT), referred to herein as an ACS-PT, supports WPT to the UE. Using an ACS-PT allows the UE 110 to receive power from multiple base stations simultaneously which reduces WPT interruptions while the UE is mobile and facilitates a higher power transfer rate while using far-held wireless power transfer.

[0008] In some aspects, the present disclosure discloses a method performed by a first base station (e.g., an ACS-DT BS) and a second base station (e.g., an ACS-PT BS) with hardware and software for performing the method. The method includes the first base station establishing a first active-coordination-set (ACS) for communicating user plane data between the first ACS and a user equipment (UE). The first ACS includes the first base station and additional base stations. The method also includes the first base station performing a wireless power transfer measurement operation to identify a second set of base stations for a second ACS. The second ACS wirelessly transfers power between the second ACS and the UE, and the second set of base stations includes a second base station. The method further includes the first base station transmitting a first message, to the UE, indicating a set of frequencies and a set of time slots for wireless powder transfer from the second ACS to the UE. The method further includes the first base station transmitting a second message, to the second base station, indicating the second set of base stations in the second ACS.

[0009] In some aspects, the present disclosure discloses a method performed by a first base station (e.g., an ACS-PT BS) and a second base station (e.g., an ACS-DT BS) with hardware and software for performing the method. The method includes receiving, from a second base station, a request to perform a wireless power transfer measurement operation with a user equipment (UE). Consequently, in response to the request, the first base station performs a wireless powder transfer measurement operation with the UE. The method further includes receiving, from the second base station, a first message indicating a first set of base stations for a first active-coordination-set (ACS) for power transfer to the UE from the first ACS. The first set of base stations includes the first base station. The method further includes the first base station coordinating the wireless power transfer to the UE from the first set of base stations of the first ACS (e.g., ACS-PT).

[0010] In some aspects the present disclosure discloses a method performed by a UE, and a UE with hardware and software for performing the method. The method includes transmitting, via a first active-coordination-set (ACS) for communicating user plane data between the first ACS and the UE, a request for far-held wireless power transfer. The first ACS includes a first set of base stations and the first set of base stations includes the first base station. The method also includes performing a wireless power transfer measurement operation to identify a one or more base stations for a second ACS. The second ACS is for power transfer from the second ACS to the UE, and the second set of base stations includes a second base station. The method further includes receiving, via the first ACS, a first message indicating a set of frequencies and a set of time slots for wireless power transfer from the second ACS to the UE. The method also includes receiving power wirelessly from one or more of the base stations of the second ACS.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The described embodiments and the advantages thereof may best be understood by reference to the following description taken in conjunction with the accompanying drawings. These drawings in no way limit any changes in form and detail that may be made to the described embodiments by one skilled in the art without departing from the spirit and scope of the described embodiments.

[0012] FIG. 1 illustrates an example wireless communication system for wireless power transfer, according to some embodiments.

[0013] FIG. 2 illustrates an example wireless communication system for wireless power transfer, according to some embodiments.

[0014] FIG. 3 illustrates an example diagram of a UE, according to some embodiments.

[0015] FIGS. 4A-4C illustrates an example diagrams of base stations, according to some embodiments.

[0016] FIG. 5 is a signaling diagram illustrating an example process of transferring power wirelessly to a UE, according to some embodiments. [0017] FIG. 6 is a signaling diagram illustrating an example process of performing a WPT measurement operation with a UE transmitting a WPT reference signal, according to some embodiments.

[0018] FIG. 7 is a signaling diagram illustrating another example process of performing a WPT measurement operation with candidate base stations transmitting WPT reference signals, according to some embodiments.

[0019] FIG. 8 a signaling diagram illustrating an example process of performing a measurement operation active-coordination-set for wireless power transfer, according to some embodiments.

[0020] FIG. 9 is a flow diagram illustrating an example method of a base station coordinating wireless power transfer to a UE via WPT, according to some embodiments.

[0021] FIG. 10 is a flow diagram illustrating an example method of wireless power transfer from a coordinating ACS-PT BS to a UE, according to some embodiments.

[0022] FIG. 11 is a flow diagram illustrating an example method of a UE receiving power via WPT, according to some embodiments.

DETAILED DESCRIPTION

[0023] For ease of illustration, the following techniques are described in an example context in which one or more UE devices and RANs implement one or more radio access technologies (RATs) including at least a Fifth Generation (5G) New Radio (NR) standard (e g., Third Generation Partnership Project (3GPP) Release 15, 3GPP Release 16, etc.) (hereinafter, "5G NR" or "5G NR standard"). However, the present disclosure is not limited to networks employing a 5GNR RAT configuration, but rather the techniques described herein can be applied to any combination of different RATs employed at the UE devices and the RANs including 6G and other evolutions of 3GPP access and Wireless Local Area Networks (WLANs) implementing the IEEE 802 protocol or other evolutions of non-3GPP access. Also, the present disclosure is not limited to the examples and context described herein, but rather the techniques described herein can be applied to any network environment implementing wireless power transfer.

[0024] FIG. 1 is a block diagram illustrating an example wireless communication system 100A for wireless power transfer, according to some embodiments. The wireless communication system 100 includes a UE device 110, and base stations 121, 122, 123, 131, 132, and 133. In one embodiment, the wireless communication system 100A is part of a cellular network or other type of wireless communication system. The wireless communication system 100A may include a radio access network (RAN) that is accessible using, for example, a 5G NR RAT or future evolutions, versions, or generations. A RAN implementing a 5GNR RAT may be referred to as a 5GNR RAN or an NR RAN. As mentioned above, the techniques described herein apply to other cellular networks and other types of wireless communication systems. The wireless communication system 100A may include additional components not shown in FIG. 1.

[0025] The RAN may include one or more of the base stations 121, 122, 123, 131, 132, and 133 operable to wirelessly communicate with the UE devices 110 within signal range. A base station may be implemented as an integrated gNB base station or as a distributed base station with a central unit (CU) and one or more distributed units (DU) and optionally one or more remote units (RUs). Irrespective of base station architecture, each base station supports at least one "cell" of coverage for the RAN. A base station defines a macrocell, microcell, small cell, picocell, or the like, or any combination thereof. A base station may also be referred to as an access point, a wireless access point, etc. The base station operates as an "air interface" to establish radio frequency (RF) wireless communication links (e.g., an upstream link or uplink toward a CN, a downstream link or downlink toward a UE) with UE devices 110. These wireless communication links then serve as data paths (including control information) between the UE devices 110 and a core network coupled to the base stations 121, 122, 123, 131, 132, and 133, which is also coupled to the one or more external networks, for providing various services to the UE devices 1 10.

[0026] As shown, the base stations 131, 132, and 133 are part of an Active Coordination Set for data transfer (ACS-DT) 130. In one embodiment, an ACS-DT 130 is set of base stations determined (e.g., identified, selected, etc.) by the UE 110 to be usable for wireless communication. The base stations 131, 132, and 133 in the ACS-DT 130 performjoint transmission and/or reception (joint communication) of user plane data and control plane messages/messaging between the UE 110 and the base stations 131, 132, and 133 in the ACS- DT 130. A coordinating base station of the ACS-DT coordinates joint transmission and/or reception for the UE 110. For example, base station 131 may be a coordinating base station. The coordinating base station (e.g., base station 131) schedules air interface resources for the set of ACS-DT base stations communicating with the UE 110.

[0027] The UE device 110 may represent any of a variety of electronic devices capable of wired and/or wireless communications, such as a smartphone, a tablet computer, a notebook computer, a desktop computer, a wearable device (e.g., smartwatch, headset, wireless earbuds, fitness tracker, blood pressure monitor, smart jewelry, smart clothing, smart glasses, etc.), an automobile or other vehicle employing wireless communication services (e.g., for navigation, provision of entertainment services, in-vehicle mobile hotspots, etc.), a gaming device, a media device, an loT device (e.g., sensor node, controller/ actuator node, or a combination thereof), and another device capable of wired and/or wireless communication.

[0028] As illustrated in FIG. 1, base stations 131, 132, 133, and 123 are equipped to transmit RF signals for communicating data to the UE 110 (indicated by the dotted ovals between the base stations 131, 132, 133, 123, and the UE 110). Additionally, base stations 121, 122, and 123 are equipped to transmit RF signals for WPT to the UE (indicated by the dashed ovals between base stations 121, 122, and 123, and the UE 110). A single base station may participate in the ACS- DT 130, the ACS-PT 120, both (e g., base station 123), or neither (not shown).

[0029] As discussed above, the UE 110 discharges internal power sources to maintain communications. Instead of recharging a UE battery using a wire or near-field wireless charging at a range of less than one meter (e.g., for a handheld or smaller UE), wireless power transfer (WPT) uses radio-frequency (RF) signals to charge the UE 110 at longer distances/ranges (e.g., at a range of tens of meters for a handheld or smaller UE). WPT improves UE 110 mobility while the UE 110 is charging. However, due to obstacles within the environment (e.g., walls, windows, or other parts of a building, furniture, people, etc.) where the UE 110 is located or moving, it may be difficult to maintain efficient wireless power transfer to the UE 110.

[0030] The present disclosure addresses the above-noted and other deficiencies by leveraging the use of an ACS for wireless power transfer (e.g., wireless charging) to the UE 110. A separate ACS, referred to herein as an ACS-PT 120, performs WPT to the UE. A coordinating base station of the ACS-DT 130 (e.g., base station 131), referred to herein as a coordinating ACS-DT base station, collaborates with a UE 110 to identify a set of base stations (e.g., base stations 121, 122, and 123) to use for the ACS-PT 120 for that UE 110. The coordinating ACS- DT base station identifies the set of base stations for the ACS-PT 120 using one or more reference signals for WPT (i.e., WPT reference signals), as discussed in more detail below.

[0031] After identifying the set of base stations for the ACS-PT 120, the coordinating ACS-DT 130 base station may identify or select a coordinating base station for the ACS-PT 120 (e.g., base station 121) based on various parameters, criteria, etc. The coordinating base station for the ACS-PT 120 may be referred to herein as the coordinating ACS-PT base station. The coordinating ACS-DT base station (e.g., base station 131) transmits a message to the coordinating ACS-PT base station (e.g., base station 121) to indicate (e.g., identify) which base stations are part of the ACS-PT 120. The coordinating ACS-PT base station (e.g., base station 121)) transmits messages to the other base stations identified in the message (e.g., base stations 122 and 123) to add the other base stations to the ACS-PT 120. The coordinating ACS-DT base station and the coordinating ACS-PT base station coordinate with each other to facilitate the wireless power transfer to the UE 110, as discussed in more detail below. The coordinating ACS-DT base station and the coordinating ACS-PT base station may also coordinate with each other to add or remove base stations from the ACS-PT 120 as wireless conditions change due the mobility of the UE 110, base station mobility, interference, or other wireless channel factors.

[0032] Using the ACS-PT 120 for WPT allows the network to transfer power to the UE 110 with fewer interruptions and at a higher power transfer rate. The ACS-PT 120 allows the UE 110 to receive power from multiple base stations simultaneously which reduces the interruptions and facilitates the higher power transfer rate.

[0033] FIG. 2 is a block diagram illustrating an example wireless communication system 100B for wireless power transfer, according to some embodiments. The wireless communications system 100B (also referred to as a wireless wide area network (WWAN)) includes a base stations 121, 122, 123, 131, 132, and 133, UE 110, and a core network 240 (e.g., a 5G Core (5GC)).

[0034] The base stations 121, 122, 123, 131, 132, and 133 configured for 5GNR may interface with core network 240 through backhaul links including NG interfaces 252; interfaces 253, 254 to an ACS server 241; and Xn interfaces 225, 235, 255 (as well as other backhaul links not shown ). Any one or more of the base stations 121, 122, 123, 131, 132, and 133 may perform one or more of the following functions: wireless power transfer, transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multicast broadcast service (MBS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, delivery of warning messages, and other functions.

[0035] The base stations 121, 122, 123, 131, 132, and 133 may wirelessly communicate with the UE 110. The base stations 121, 122, 123, 131, 132, and 133 may provide communication coverage for a respective geographic area. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs), which may provide sen ice to a restricted group known as a closed subscriber group (CSG). The communication link between a base station and the UE 110 may include uplink (UL) transmissions from the UE 110 to a base station and/or downlink (DL) transmissions from the base station to the UE 110. The communication link may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming (e.g., as represented by the dashed and dotted ovals in FIG. 1), and/or transmit diversity.

[0036] The core network 240 provides various services to the UE 110. Examples of these services include voice or data services via packet-switched networks, messaging services such as simple messaging service (SMS) or multimedia messaging service (MMS), audio, video, or multimedia content delivery, presence services, and so on. Multiple wireless communication links from multiple base stations can be configured for Coordinated Multipoint (CoMP) communication with the UE 110. A base station can aggregate multiple wireless communication links in a earner aggregation to provide a higher data rate for the UE devices 110. The base station can configure multiple wireless communication links for single-RAT or multi-RAT dual connectivity (MR-DC).

[0037] The core network 240 includes an Access and Mobility Management Function (AMF) 243, a Session Management Function (SMF) 244, and a User Plane Function (UPF) 242. The AMF 243 processes control signaling between the UE 110 and the core network 240. Generally, the AMF 243 provides QoS flow and session management. The SMF 244 interacts with the AMF 243 to establish, modify, and release protocol data unit (PDU) sessions. All user Internet protocol (IP) packets are transferred through the UPF 242. The UPF 242 provides UE IP address allocation as well as other functions. The UPF 242 is connected to the IP Services 245. The IP Services 245 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a PS Streaming Service, and/or other IP services.

[0038] When the UE 110 creates or updates an ACS, the UE 110 communicates the requested identities of the base stations for the ACS or the changes to the ACS (e.g., identities of base stations to be added/removed from the ACS), to an ACS server 241 that stores the identities of the base stations in the ACS(s) for each UE 110 operating in the wireless communication system 100B. An ACS (e.g., an ACS-DT or an ACS-PT) is specific to a particular UE. Other UEs may have different ACSs that include the same or different base stations. Although shown in the core network 240, alternatively the ACS server 241 may be an application server located outside the core network 240. The UE 110 communicates the ACS or ACS updates using the coordinating base station (base station 131 of ACS-DT), which is connected to the ACS server 241 using interface 253 (e.g., an N-ACS interface). Optionally or alternatively, the UE 110 communicates the ACS or ACS updates to the ACS server 241 using the Access and Mobility Function 243 (AMF 243), which is connected to the coordinating base station (base station 131 of ACS-DT 130) via interface 253. The AMF 243 relays ACS-related communications to and from the ACS server 241 using an ACS-AMF interface (not shown in FIG. 2).

[0039] The ACS server 241 may be implemented as a single network node or the functionality of the ACS server 241 may be distributed across multiple network nodes and/or devices in any fashion suitable to perform the functions described herein. The ACS server 241 includes processor(s) and computer-readable storage media (CRM) 704. The CRM includes applications and/or an operating system of the ACS server 241, which are executable by the processor(s) to enable communication with the UE 110 (via at least a base station), the coordinating base station 131 of ACS-DT 130, the coordinating base station 121 of ACS-PT 120, and the AMF 243. The ACS server 241 communicates using various network interfaces 253, 254 to base stations 131 and 12E

[0040] FIG. 3 illustrates an example diagram of the UE 110, according to some embodiments. The UE 110 may include additional functions and interfaces that are omitted from FIG. 3 for the sake of clarity. The UE 110 includes communication antenna array 322 and power antenna array 323. The communication antenna array 322 communicates data (e.g., user plane and/or control plane data) with one or more base stations and other devices. The antenna array 323 receives RF signals from one or more base stations which are converted into power. Each of the communication antenna array 322 and power antenna array 323 may include an array of multiple antennas that are configured similarly to or differently from each other. The power antenna array 323 may transmit RF signals to a device to provide wireless power transfer (WPT) to the UE 110 at longer distances/ranges (e.g., at a range of tens or hundreds of meters).

[0041] The UE 110 also includes a radio frequency front end 302 (RF front end 302) and a transceiver 304. The transceiver 304 may include one or more of a Wi-Fi transceiver, a long term evolution (LTE) transceiver, a 5G NR transceiver, and a 6G NG transceiver for communicating with base stations and/or access points in a homogeneous or heterogeneous RAN or wireless communication system. The RF front end 302 of the UE 110 can couple or connect the transceiver 304 to the communication antenna array 322 and power antenna array 323 to facilitate various types of wireless communication and to facilitate WPT. The RF front end 302 (along with the communication antenna array 322 and power antenna array 323) can be tuned to, and/or be tunable to, one or more frequency bands defined by the 3GPP LTE, 5G NR, and 6G communication standards and implemented by the LTE transceiver 304, the 5GNR transceiver 208, and/or the 6G transceiver 210. Additionally, the communication antenna array 322 and the power antenna array 323, the RF front end 302, the LTE transceiver 304, the 5G NR transceiver 208, and/or the 6G transceiver 210 may be configured to support beamforming for the transmission and reception of communications with the base stations. By way of example and not limitation, the communication antenna array 322 and the power antenna array 323, and the RF front end 302 can be implemented for operation in sub-gigahertz bands, sub-6 GHz bands, and/or above 6 GHz bands that are defined by the 3GPP LTE, 5GNR, and 6G communication standards.

[0042] In some implementations, the memory 308 includes an ACS-DT component 321 and an ACS-PT component 324. The ACS-DT component 321 can communicate with the communication antennas 322, the RF front end 302, and the communications transceiver 304, to monitor the quality of the wireless communication links with one or more base stations. Based on this monitoring, the ACS-DT component 321 can determine to add or remove base stations 120 from the ACS and/or request a base station to assign resources for the transmission of an uplink ACS sounding signal. The ACS-DT component 321 can also communicate using the antennas 322, the RF front end 302, the LTE transceiver 304, the 5G R transceiver, and/or the 6G transceiver 210 to transmit uplink data via one ACS and receive downlink data via a different ACS. Thus, the UE 110 uses its ACS-DT components 321 to communicate with base stations. Conversely, the UE 110 uses its ACS-PT component 324 to receive power wirelessly from base stations.

[0043] FIG. 4A-4C illustrate example device diagrams of base stations 123, 131, and 121, according to some embodiments. Each of the base stations 123, 131, and 121 may include additional functions and interfaces that are omitted from FIGS. 4A-4C for the sake of clarity. Base station 123 is configured to communicate data with a UE and to transfer power wirelessly to the UE. Base station 131 is configured to communicate data with the UE (but is not configured to transfer power wirelessly to the UE). Base station 121 is configured to transfer power wirelessly to the UE (but is not configured to communicate data with the UE).

[0044] The base station 123, shown in FIG. 4A, includes a single network node (e g., a gNode B) that supports both wireless communications and wireless power transfer. The base station 123 includes antenna array 422 (for communicating data) with a UE, antenna array 423 (for wireless power transfer), a radio frequency front end 402 (RF front end 402), a transceiver 404, a processor 406, and computer-readable storage media memory 408. The antenna arrays 422 and 423 of the base station 122 may include an array of multiple antennas that are configured similarly to or differently from each other. The RF front end 402 of the base station 123 can couple or connect the transceiver 404 to the antenna arrays 422 and 423, to facilitate various types of wireless communication and wireless power transfer. The antenna arrays 422 and 423 and the RF front end 402 can be tuned to, and/or be tunable to, one or more frequency bands defined by the 3GPP or Wi-Fi communication standards, and implemented by the transceiver 404. Additionally, the antenna arrays 422 and 423, the RF front end 402, the transceiver 404 may be configured to support beamforming, such as Massive-MIMO, for the transmission and reception of communications with the UE 110.

[0045] The ACS-DT component 421 configures the transceiver 404 for communication with the UE 110, as well as communication with a core network, such as the core network 240 illustrated in FIG. 2, and routing user-plane and control-plane data for joint communication. Additionally, the ACS-DT component 421 may allocate air interface resources and schedule communications for the UE 110 and base stations in the ACS-DT 130 when the base station is acting as a coordinating base station for the ACS-DT 130. The ACS-PT component 424 configures the transceiver 404 for communication with the UE 110 for wireless power transfer with the UE 110. Additionally, the ACS-PT component 424 coordinate with ACS-DT component 421 to allocate air interface resources and coordinate the transfer of power (e g., coordinate time slots and radio frequencies used for WPT) with base stations in the ACS-PT when the base station is acting as a coordinating base station for the ACS-PT. The ACS-DT component 421 and the ACS-PT component 424 may be implemented in whole or part as hardware logic or circuitry integrated with or separate from other components of the base station 123.

[0046] The base station 123 includes an inter-base station interface 455, such as an Xn and/or X2 interface, which ACS-DT component 421 uses to exchange user-plane and control-plane data with other base stations dunng, for example, coordinated multi-point (CoMP) or dualconnectivity (DC) situations. The ACS-PT component 424 may also use an Xn interface 455 to coordinate the WPT of the ACS-PT base stations with the UE 110. The base station 122 includes a core network NG interface 452 that the ACS-DT component 421 uses to exchange user-plane and control-plane data with core network functions and/or entities including the ACS server 241 . [0047] FIG. 4B is device diagram for the base station 131, according to some embodiments.

The components of the base station 131 illustrated in FIG. 4B are configured similarly to their counterparts descnbed in connection with FIG. 4A. As discussed above, base station 131 is configured to communicate data with a UE but is not configured to transfer power wirelessly to the UE. In this example, base station 131 does not include an antenna array for wireless power transfer, but in other embodiments an antenna array for wireless power transfer may be present but inactive.

[0048] FIG. 4C is device diagram for the base station 121, according to some embodiments. The components of the base station 121 illustrated in FIG. 4C are configured similarly to their counterparts described in connection with FIG. 4A. As discussed above, base station 121 is configured to transfer power wirelessly to a UE (but is not configured to communicate data with the UE). In this example, base station 121 does not include an antenna array for wireless data transfer, but in other embodiments an antenna array for wireless data transfer may be present but inactive.

[0049] FIG. 5 is a signaling diagram 500 illustrating an example process 500 of transferring power to a UE 110 via WPT, according to some embodiments. Initially, the UE 110 and the BS 131 may optionally establish 502 an ACS-DT. For example, the UE 110 and the BS 131 establish the ACS-DT 130 illustrated in FIG. 2 having BSs 131, 132, 133, 123. The ACS-DT may be established specifically for the UE 110, as discussed above. Alternatively, the UE 110 may be served by a single base station 131.

[0050] The UE 110 then transmits 503 a message to the coordinating base station 131, requesting wireless power transfer to the UE 110.

[0051] The BS 131 identifies 504 potential or candidate base stations 121, 122, 123 for the ACS-PT (e.g., for ACS-PT 120 illustrated in FIG. 2). For example, the BS 131 identifies base stations that are within a distance, range, etc., of the estimated location of the UE 110. The potential/ candidate base stations may be identified based on various other parameters/criteria in other embodiments. The BS 131 transmits a measurement operation request 505 to the UE and to each of the candidate base stations for the ACS-PT.

[0052] The BS performs 506, with candidate ACS-PT base stations 121, 122, 123 and the UE 110, one or more wireless power transfer measurement operations. The wireless power transfer measurement operation is discussed in more detail with reference to FIG. 6 and FIG. 7. For example, the UE 110 transmits a WPT reference signal that is detected by one or more of the base stations 121, 122, and 123. In another example, each of the base stations 121, 122, and 123 transmit different WPT reference signals that may be detected by the UE 110.

[0053] The base station 131 determines 508 (e.g., selects, identifies, etc.) the base stations for the ACS-PT based on the measurement operation results. For example, one or more measurement reports may be transmitted to the BS 131 by one or more of the UE 110, the base station 121, the base station 122, and the base station 123, as discussed in more detail with reference to FIG. 6 and FIG. 7. Based on the measurement reports, the coordinating base station 131 determines which of the candidate ACS-PT base stations 121, 122, and 123 to include in the ACS-PT. For example, the base station 121 analyzes the measurement reports to identify signal quality parameters of the reference signal received by each of the candidate ACS-PT base stations 121, 122, and 123 as exceeding athreshold value. For example, signal quality parameters in the measurements reports may be represented using a received signal strength indicator (RS SI), a reference signal received power (RSRP), a reference signal received quality (RSRQ), signal to noise and interference ratio (SINR), etc. The base station 121 may also add candidate ACS-PT base stations until their combined reference signal strength exceeds a threshold value. The coordinating base station 131 may determine, based on the position of the UE 110, which of the candidate ACS-PT base stations 121, 122, and 123 to include in the ACS- PT

[0054] The base station 131 transmits 509 messages to the selected/identified base stations to add the base stations to the ACS-PT. For example, the base station 131 transmits messages to both base stations 121 and 122 to indicate that those base stations are part of the ACS-PT. In another example, the base station transmits a message to base station 121 indicating that base stations 121 and 122 are part of the ACS-PT, and the base station 121 forwards the message to the base station 122. The base station 131 may transmit 509 a message to a base station 121 explicitly or implicitly indicating that it is a coordinating ACS-PT base station (e.g., a coordinating base station for the ACS-PT). For example, the base station 131 selects base station 121 to be the coordinating ACS-PT base station based on the reported available resources at the base stations 121 and 122 (e.g., the available processing/computing resources, the available RF resources, etc.), based on distance/range to the UE 110, based on reported signal quality parameters, etc. Various other parameters/ criteria may be used by the base station 121 to select the coordinating ACS-PT base station in other embodiments.

[0055] The base station 121 (e.g., the coordinating ACS-PT base station) determines 510 a WPT configuration for the UE 110 and specifies one or more of time slots, radio frequencies, beam identities, and/or waveforms for WPT. The base station 121 may determine a WPT configuration for the UE 110 based on UE feedback, such as UE desired beam for WPT, UE current battery level, and/or UE desired duty cycle on WPT.

[0056] The base station 121 transmits 512 to the BS 131 a WPT configuration message indicating the time slots, frequencies, beam identities, and/or waveforms of the WPT for the UE 110. The base station 131 forwards 14 to the UE 110 the WPT configuration message (and/or other data) indicating the time slots, frequencies, beam identities, and/or waveforms.

[0057] The base stations of the ACS-PT perform 515 WPT to the UE 110 m accordance with the WPT configuration. For example, at operation 516, the base station 121 transfers power to the UE 110 by transmitting RF signals to the UE 110 (which the UE 110 will convert to power/energy). At operation 518, the base station 122 may transfer power to the UE 110 by transmitting RF signals to the UE 110 (which the UE 110 will convert to power/energy).

[0058] The base stations of the ACS-PT may perform operations 516 and 518 serially. For example, the base station 121 begins transferring power to the UE 110 by transmitting RF signals to the UE 110 at time 0 or time 1, and the base station 122 begins transferring power to the UE 110 by transmitting RF signals to the UE 110 at the other time. Time 1 occurs after time 0 and occurs when the other base station of the ACS-PT is not transmitting RF signals to the UE 110.

[0059] The base stations of the ACS-PT may perform operations 516 and 518 in parallel. For example, the base station 121 begins transferring power to the UE 110 by transmitting RF signals to the UE 110 at time 0 or time 1, and the base station 122 begins transferring power to the UE 110 by transmitting RF signals to the UE 110 at the same time or during an overlapping time period. Time 1 occurs after time 0 and occurs when the other base station of the ACS-PT is still transmitting RF signals to the UE 110.

[0060] The ACS-PT may optionally update 520 the ACS-PT to add base stations to the ACS-PT 120 and/or remove base stations from the ACS-PT 120. FIG. 8 contains further details regarding the procedure. For example, the UE 110 measures the amount of power received from the base stations 121 and 122 at their respective time slots. The UE 110 may determine that the amount of power received from base station 122 at the time slots for base station 122 is below a threshold amount of power. The ACS-PT may also be updated when the UE has moved or changed location, if one of the base stations in the ACS-PT has moved or changed location, there is wireless interference, or there is blockage of the wireless signals for WPT caused by moving objects.

[0061] The measurement operations 506 of method 500 may be performed in several ways. FIG. 6 demonstrates a UE-transmitted wireless power measurement operation 506A while FIG. 7 demonstrates a BS-transmitted wireless power measurement operation 506B.

[0062] FIG. 6 is a signaling diagram 506 A illustrating an example process of performing a WPT measurement operation with a UE transmitting a WPT reference signal, according to some embodiments. In this implementation, the UE 110 transmits a WPT reference signal (WPT-RS), and candidate ACS-PT BSs provide signal strength reports on that WPT-RS so that the coordinating ACS-DT BS 131 can select BSs for the ACS-PT.

[0063] The coordinating ACS-DT BT 131 determines 602 one or more air interface resources (e.g., a set of time slots, a set of transmission frequencies, a set of beams, etc.) for the UE 110 to transmit a wireless power transfer reference signal (e g., a reference signal that is used for wireless power transfer purposes). For example, the base station 131 determines the one or more time slots and transmits a message (or other control message) to the base station 121 indicating the one or more timeslots. The base station 121 may forward the information about the timeslots to the other candidate ACS-PT base stations or the base station 131 may transmit the information about the timeslots to the other candidate ACS-PT base stations.

[0064] The coordinating ACS-DT base station 131 transmits 603 a message to the base stations 121, 122, 123 to indicate the time slots for receiving the UE-transmitted reference signal at operation 606.

[0065] The base station 131 transmits 604 a message (or other control message) to the UE 110 instructing the UE 110 to transmit the wireless power transfer reference signal during one or more identified time slots. In response to receiving 604 the control message, the UE 110 transmits 606 the wireless power transfer reference signal which might be received by the base stations 121, 122, and 123. Each of the candidate base stations 121, 122, and 123 measures 608 the received strength of the wireless power transfer reference signal from the UE.

[0066] Each candidate base station 123, 122, 121 transmits 610, 612, 614 to BS 131 a measurement report indicating the strength of the wireless power transfer reference signal that was received/detected by that base station 123. In other embodiments, the base stations 123 and 122 transmit their respective measurement reports to coordinating power transfer base station 121 and base station 121 transmits, to the coordinating data transfer base station 131, a message (e.g., a combined measurement report) that includes all of the individual candidate ACS-PT BS measurement reports, or a subset of the individual candidate ACS-PT BS measurement reports (e.g., measurement reports with a signal strength achieving a certain threshold).

[0067] FIG. 7 is a signaling diagram 506B illustrating an example process of performing a WPT measurement operation with candidate base stations transmitting WPT reference signals, according to some embodiments. In this implementation, which is an alternative to FIG. 6, the candidate ACS-PT BSs transmit WPT reference signals and the UE 110 provides signal strength reports on those downlink WPT-RSs so that the coordinating ACS-DT BS 131 can select BSs for the ACS-PT.

[0068] The base station 131 determines 702 one or more time slots (e.g., a set of time slots) for each of the base stations 121, 122, and 123 to transmit a respective wireless power transfer reference signal (e.g., reference signals that is used for wireless power transfer purposes). For example, the base station 131 determines a first time slot for base station 121 to transmit a first wireless power transfer reference signal, a second time slot for base station 122 to transmit a second wireless power transfer reference signal, and a third time slot for base station 123 to transmit a third wireless power transfer reference signal. Individual WPT-RSs may have the same waveform or may have different waveforms.

[0069] The coordinating ACS-DT base station 131 transmits 703, to the UE 110, a message indicating the time slots for receiving the BS-transmitted reference signals at operation 704.

[0070] The base station 131 may transmit 704 a message indicating the one or more time slots to one or more of the base stations 121, 122, and 123 and the UE 110. For example, the base station 131 transmits a message to each of the base stations 121, 122, and 123 indicating one or more time slots when each candidate ACS-PT base station should transmit its respective wireless power transfer reference signal. In another example, the base station 131 transmits a message indicating the time slots to the base station 121, and the base station 121 may forward or transmit data indicating the time slots to the other base stations in the ACS-PT.

[0071] The base station 123 transmits 706 a first wireless power transfer reference signal to the UE 110 (during a first time slot). The base station 122 transmits 708 a second wireless power transfer reference signal to the UE 110 (during a second time slot). The base station 121 transmits 710 a third wireless power transfer reference signal to the UE 110 (during a third time slot). In another embodiment, the base stations 123, 122, and 121 may simultaneously transmit wireless power transfer reference signals.

[0072] The UE 110 transmits 712 one or more measurement reports (e.g., a set of measurement reports) and/or other data to the base station 131. The coordinating ACS-DT base station uses these WPT-RS measurement reports to select base stations for the ACS-PT. For example, as previously discussed, a BS performs measurement operations at operation 506 in FIG. 5 according to the signaling diagram 506A in FIG. 6, and then determines a base station (from among candidate base stations) for ACS-PT 120 at operation 508 in FIG. 5 based on the UE reference signal measurement operation results. As another example, a BS performs measurement operations at operation 506 in FIG. 5 according to the signaling diagram 506B in FIG. 7, and then determines a base station (from among candidate base stations) for ACS-PT 120 at operation 508 in FIG. 5 based on the BS reference signal measurement operation results.

[0073] FIG. 8 is a signaling diagram 800 illustrating an example process 800 of updating an active-coordination-set for power transfer (ACS-PT) that was illustrated in operation 520 of FIG. 5, according to some embodiments. One or more of the base station 131 and the UE 110 determine 802 that the ACS-PT should be updated (e.g., to add and/or remove a base station from the ACS-PT). For example, one or more of the UE 110 and the base station 131 penodically performs measurement operations (discussed above in FIGS. 6 and 7). In another example, the UE 110 periodically sends messages, reports, etc., to the base station 131 indicating the amount of power and/or a power transfer rate with current base stations in the ACS-PT. The base station 131 may determine that one or more base stations should be added/removed from the ACS-PT based on these reports/messages. For example, if the UE power level is above a threshold (e.g., a battery level is above a threshold), the number of base stations in the ACS-PT can be reduced. The UE 110 may transmit a message to the base station 131 indicating that the UE power level is above the threshold. In another example, if a moving object blocks WPT signals from a base station in the ACS-PT such that the wireless power transfer rate falls below another threshold, another base station may be added to the ACS-PT.

[0074] The base station 131 determines 804 one or more updates for the ACS-PT. For example, the base station 131 determines that base station 122 should be removed from the ACS-PT and that base station 123 should be added to the ACS-PT, based on measurement operations, measurement reports, amount of power transferred to the UE 110, power transfer rates to the UE 110, and various other factors/criteria. For example, operation 506 may be periodically performed to evaluate the effectiveness of the ACS-PT base stations at transferring power to the UE 110. If the power transfer rate to the UE 110 is below a threshold, the UE may perform operation 503 and restart process 800.

[0075] The base station 131 transmits 806 a message indicating the updates for the ACS-PT to the coordinating ACS-PT base station 121. For example, the base station 131 transmits a message to the base station 121 indicating that base station 123 should be added to the ACS-PT and that base station 122 should be removed from the ACS-PT.

[0076] The base station 121 transmits 808 a message to the base station 123 indicating to the base station 123 that it has been added to the ACS-PT. The message may also include information indicating time slots, frequencies, waveforms, etc., for the base station 123 to use when transferring power to the UE 110. Alternatively, the base station 121 may transmit a separate message indicating time slots, frequencies, waveforms, etc., for the base station 123 to use.

[0077] The base station 121 transmits 810 a message to the base station 122 indicating that the base station 122 has been removed from the ACS-PT.

[0078] The base station 131 transmits 812 to the UE 110 updates to one or more of the time slots, frequencies, and waveforms for WPT. The base station 131 may transmit a message indicating the updated time slots, updated frequencies, and/or updated wave forms to the UE 110. The updated time slots correspond to the time slots for receiving the BS -transmitted reference signals.

[0079] At operation 813, one or more base stations in the updated ACS-PT performs WPT to the UE 110. For example, at operation 814, the base station 121 transfers power to the UE 110 by transmitting RF signals to the UE 110 (which the UE 110 will convert to power/energy for battery charging). At operation 816, the base station 123 may transfer power to the UE 110 by transmitting RF signals to the UE 110 (which the UE 110 will convert to power/energy for battery charging).

[0080] The signaling processes illustrated in FIGS. 5-8 (or portions of the processors) may also be represented as flow diagrams. FIGS. 9-11 are flow diagrams that illustrate the operations of the processes illustrated in FIGS. 5-8.

[0081] FIG. 9 is a flow diagram illustrating an example method of a base station coordinating wireless power transfer to a UE via WPT, according to some embodiments. The method 900 is performed by a base station, such as coordinating base station 131 illustrated in FIGS. 1 and 2. [0082] As shown in FIG. 9, the method 900 optionally establishes 902 an ACS-DT for data transfer with a UE (e.g., UE 110 illustrated in FIGS. 1 and 2; signal 502 in FIG. 5). As discussed above, the ACS-DT allows for joint transmission and/or reception (joint communication) of user plane data and control plane messages/messaging between the UE 110 and the base stations of the ACS-DT. The method 900 also includes block 903 of receiving a request for WPT from a UE (e.g., signal 503 in FIG. 5). The message further includes block 904 of identifying potential base stations for the ACS-PT (e.g., signal 504 in FIG. 5).

[0083] The method 900 includes the block 905 of transmitting a measurement operation request to the UE 110 and to each of the candidate base stations for the ACS-PT (e.g., 505 in FIG. 5).

[0084] The method 900 includes the block 906 of performing a measurement operation to identify base stations for an ACS-PT (e.g., signal 506 in FIG. 5). As discussed above, the ACS- PT supports long-range wireless power transfer to the UE via the ACS-PT. In one embodiment, the measurement operation may include the operations discussed above in conjunction with FIG. 5 element 506 and FIGS. 6 and 7.

[0085] The method 900 also includes the block 908 of determining the base stations for the ACS-PT based on the measurement operation results (e.g., operation 508 in FIG. 5). The method 900 further includes block 909 of transmitting a first message to a second base station (e.g., a coordinating base station for the ACS-PT, a coordinating ACS-PT base station, etc.) indicating the base stations that are part of the ACS-PT (e.g., signals 509 in FIG. 5). For example, the message includes identifiers, names, etc., for the base stations that are part of the ACS-PT and an indicator for the coordinating base station of the ACS-PT. The message may also include data/information that indicate one or more time slots for WPT transmissions, RF frequencies for WPT transmissions, and beams for WPT transmission. The base stations of the ACS-PT may transmit power wirelessly to the UE based on the time slots and frequencies.

[0086] The method 900 further includes the block 912 of receiving, from a coordinating base station of ACS-PT, a WPT configuration message indicating the time slots, frequencies, beam identities, and/or waveforms of the WPT for the UE (e.g., signal 512 in FIG 5).

[0087] The method 900 further includes the block 914 of transmitting a second message to the UE indicating a set of frequencies, waveforms, and a set of time slots for WPT to the UE (e.g., signal 514 in FIG. 5). For example, the message indicates a first time slot, a first beam, and a first frequency that a first base station of the ACS-PT uses to transmit power to the UE, a second time slot, a second beam, and a second frequency that a second base station of the ACS-PT uses to transmit power to the UE, a third time slot, a third beam, and a third frequency that a third base station of the ACS-PT uses to transmit power to the UE, etc.

[0088] The method 900 further includes block 920 for optionally updating the ACS-PT (e.g., operation 520 in FIG. 5). For example, one or more base stations may be added to the ACS-PT and/or one or more base stations may be removed from the ACS-PT. In one embodiment, the updating the ACS-PT may include the operations discussed above in conjunction with FIG. 8. Alternatively, the method 900 may proceed back to block 906 for updates to the ACS-PT. The additional messages for the additional updates (which are transmitted at block 920 or as a repeat of blocks 909 - 914) to the ACS-PT may indicate updates to the ACS-PT (e.g., identifiers and/or WPT information for the base stations that are added/removed from the ACS-PT instead of for all of the base stations in the ACS-PT).

[0089] FIG. 10 is a flow diagram illustrating an example method of wireless power transfer from a coordinating ACS-PT BS to a UE, according to some embodiments. The method 1000 is performed by a base station, such as base station 121 illustrated in FIGS. 1 and 2.

[0090] As shown in FIG. 10, the method 1000 includes the block 1005 of receiving a request to perform a measurement operation (e.g., as discussed above in conjunction with operation 505 of FIG. 5). For example, the message may be received from a coordinating ACS-DT base station (e.g., from base station 131 illustrated in FIGS. 1 and 2).

[0091] The method 1000 also includes the block 1006 of performing the measurement operation (e.g., signal 506 in FIG. 5). In one embodiment, the measurement operation may include the operations discussed above in conjunction with FIGS. 6 and 7 (e.g., as illustrated in operations 602-614 of FIG. 6 and operations 702-712 of FIG. 7).

[0092] The method 1000 further includes the block 1009 of receiving a message identifying the base stations for the ACS-PT. For example, the message includes a list of identifiers, names, etc., for the base stations included in the ACS-PT (e.g., as illustrated in operation 509 of FIG. 5 and previously described). Depending on the message instructions or the configuration in the message, coordinating ACS-PT base station may forward the message or the information of the message to the non-coordinating ACS-PT base stations.

[0093] The method 1000 further includes the block 1010 of determining a WPT configuration for the UE 110 to specify one or more of time slots, radio frequencies, beam identities, and/or waveforms for WPT (e.g., operation 510 in FIG. 5). Next, the method 1000 includes the block 1012 of transmitting to the ACS-DT coordinating BS (e.g., BS 131) a WPT configuration message indicating the time slots, frequencies, beam identities, and/or waveforms of the WPT for the UE 110 (e.g., operation 512 in FIG. 5).

[0094] The method 1000 further includes the block 1016 of transferring power to the UE 110 by transmitting RF signals to the UE 110, which the UE 110 will convert to pow er/ energy (e.g., operation 516 in FIG. 5).

[0095] The method 1000 further includes the block 1020 of optionally updating the ACS-PT (e.g., operation 520 in FIG. 5 or method 800 of FIG. 8). The method 1000 may optionally proceed back to block 1005 for additional updates to the ACS-PT. The additional messages for the additional updates (which are transmitted at block 1012) to the ACS-PT may be full-style configuration updates to the ACS-PT or delta-style configuration updates (e.g., identifiers and/or WPT information for the base stations that are added/removed from the ACS-PT instead of a full-sty le configuration listing all of the base stations in the ACS-PT).

[0096] FIG. 11 is a flow diagram illustrating an example method of a UE receiving power via WPT, according to some embodiments. Method 1100 is perfonned by processing logic that includes hardware (e.g., circuitry, dedicated logic, programmable logic, a processor, a processing device, a central processing unit (CPU), a system-on-chip (SoC), etc.), software (e.g., instructions and/or an application that is running/executing on a processing device), firmware (e.g., microcode), or a combination thereof. The method 1100 is performed by a UE, such as UE 110 illustrated in FIGS. 1 and 2.

[0097] As shown in FIG. 11, the method 1100 includes the optional block 1102 of establishing an ACS-DT (e.g., as illustrated in operation 502 of FIG. 5) for data transfer with a UE (e.g., UE 110 illustrated in FIGS. 1 and 2). As discussed above, the ACS-DT allows for joint transmission and/or reception (joint communication) of user plane data and control plane messages/messaging between the UE 1 10 and the base stations of the ACS-DT. If optional block 1 102 is skipped, the UE still has at least one communication link with a serving base station 131.

[0098] The method 1100 also includes the block 1103 of transmitting a request for power transfer (e.g., as illustrated in operation 503 of FIG. 5). For example, block 1110 includes transmitting (by the UE) a message to the coordinating ACS-DT base station to request wireless power transfer. [0099] The method 1100 further includes the block 1105 of receiving a request to perform a measurement operation (e.g., as discussed above in conjunction with operation 505 of FIG. 5). For example, the UE 110 receives the request from a coordinating ACS-DT base station (e.g., from base station 131 illustrated in FIGS. 1 and 2).

[0100] The method 1100 further includes the block 1106 of performing a measurement operation to identify base stations for an ACS-PT. As discussed above, the ACS-PT supports long-range wireless power transfer to the UE via base stations of the ACS-PT. The measurement operation may include the operations discussed above in conjunction with FIG. 6 and 7. For example, the measurement operations 1106 of method 1100 may be performed according to UE-transmitted wireless power measurement operation 506A in FIG. 6, where the UE HO receives a control message from BS 131 that instructs the UE 110 to transmit the wireless power transfer reference signal during one or more identified time slots (e.g., operation 604 in FIG. 6); and transmit 606 the wireless power transfer reference signal (e.g., operation 606 in FIG. 6). As another example, the measurement operations 1106 of method 1100 may be performed according to BS -transmitted wireless power measurement operation 506B in FIG. 7, where UE 110 receives a message indicating one or more time slots to one or more of the base stations (e.g., operation 704 in FIG. 7), a first wireless power transfer reference signal (e.g., operation 706 in FIG. 7), a second wireless power transfer reference signal 708 (e.g., operation 708 in FIG. 7), and a third wireless power transfer reference signal to the UE 110 (e.g., operation 710 in FIG. 7). The UE 110 then transmits one or more measurement reports and/or other data to the base station 131 (e.g., operation 712 in FIG. 7).

[0101] The method 1100 further includes the block 1114 of receiving a message indicating one or more time slots and one or more frequencies for the wireless power transfer. For example, the message indicates a time slots and/or frequencies when the ACS-DT coordinating BS expects the UE to receive radio frequency signals for wireless power transfer from the base stations of the ACS-PT.

[0102] The method 1100 further includes the block 1115 of receiving power from a base station. For example, UE 110 receives RF signals from ACS-PT BSs 121, 122 and converts the RF signals to power/energy (e.g., operation 515 in FIG. 5).

[0103] The method 1100 further includes the optional block 1120 of updating the ACS-PT (e.g., as illustrated in operation 520 of FIG. 5 and method 800 of FIG. 8). For example, the UE transmits one or more messages indicating the transfer rate, amount of power transferred, etc., during different time slots. This may allow the coordinating ACS-DT base station to determine whether the ACS-PT should be updated to add and/or remove base stations. The method 1100 may optionally proceed back to block 1015 for additional updates to the ACS-PT, which could be triggered by the UE 110 battery being full (e.g., or above a threshold) and/or the power transfer rate changing (e.g., either increasing or decreasing).

[0104] In this manner, a wireless data communication base station may coordinate a set of wireless power transfer base stations to charge a UE using far-field wireless power transfer.

[0105] The detailed description set forth below is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The present disclosure provides several aspects of communication systems with reference to various apparatus and methods. The present disclosure describes these apparatus and methods in the following detailed description. These apparatus and methods are illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. For example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on a chip (SoC), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. The various processors described in this patent application may be implemented as a single core processor, or a multiple core processor, composed of a variety of materials, such as silicon, polysilicon, high-K dielectric, copper, and so on.

[0106] In some embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer- readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. For example, such computer-readable media may include a random-access memory (RAM), a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned types of computer-readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer.

[0107] The methods described herein may be performed by processing logic that includes hardware (e.g., circuitry, dedicated logic, programmable logic, a processor, a processing device, a central processing unit (CPU), a system-on-chip (SoC), etc.), software (e.g., instructions and/or an application that is running/executing on a processing device), firmware (e.g., microcode), or a combination thereof.

[0108] In addition, the methods described herein illustrates example functions used by various embodiments. Although specific function blocks ("blocks") are disclosed in the methods, such blocks are examples. That is, embodiments are well suited to performing various other blocks or variations of the blocks recited in a method. It is appreciated that the blocks in a method may be performed in an order different than presented, and that not all of the blocks in a method may be performed.

[0109] Furthennore, it is appreciated that the blocks in the processes and/or signal diagrams illustrated herein may be performed in an order different than presented, that not all of the blocks in may be performed, and the blocks may be combined with other processes presented herein.

[0110] Unless specifically stated otherwise, terms such as “establishing,” “performing,” “transmitting,” “receiving,” “coordinating,” or the like, refer to actions and processes performed or implemented by computing devices that manipulates data represented as physical (electronic) quantities within the computing device's registers and memories into other data similarly represented as physical quantities within the computing device memories or registers or other such information storage, transmission or display devices. Also, the terms "first," "second," "third," "fourth," etc., as used herein are meant as labels to distinguish among different elements and may not necessarily have an ordinal meaning according to their numerical designation.

[0111] Examples described herein also relate to an apparatus for performing the operations described herein. This apparatus may be specially constructed for the certain purposes, or it may include a general purpose computing device selectively programmed by a computer program stored in the computing device. Such a computer program may be stored in a computer-readable non-transitory storage medium. [0112] The methods and illustrative examples described herein are not inherently related to any particular computer or other apparatus. Various general purpose systems may be used in accordance with the teachings described herein, or it may prove convenient to construct more specialized apparatus to perform the method steps. The structure for a variety of these systems will appear as set forth in the description above.

[0113] The above description is intended to be illustrative, and not restrictive. Although the present disclosure has been described with references to specific illustrative examples, it will be recognized that the present disclosure is not limited to the examples described. The scope of the disclosure should be determined with reference to the following claims, along with the full scope of equivalents to which the claims are entitled.

[0114] As used herein, the singular forms “a”, “an” and “the” are intended to include the plural fomis as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes”, and/or “including”, when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Therefore, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0115] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality /acts involved.

[0116] Although the method operations were described in a specific order, other operations may be performed in between described operations, described operations may be adjusted so that they occur at slightly different times or the described operations may be distributed in a system which allows the occurrence of the processing operations at various intervals associated with the processing.

[0117] Various units, circuits, or other components may be described or claimed as “configured to” or “configurable to” perform a task or tasks. In such contexts, the phrase “configured to” or “configurable to” is used to connote structure by indicating that the units/circuits/components include structure (e.g., circuitry) that performs the task or tasks during operation. As such, the unit/ circuit/ component can be said to be configured to perform the task, or configurable to perform the task, even when the specified unit/ circuit/ component is not currently operational (e.g., is not on). The units/circuits/components used with the “configured to” or “configurable to” language include hardware-for example, circuits, memory storing program instructions executable to implement the operation, etc. Reciting that a unit/circuit/component is “configured to” perform one or more tasks, or is “configurable to” perform one or more tasks, is expressly intended not to invoke 35 U.S.C. §112, sixth paragraph, for that unit/circuit/component. Additionally, “configured to” or “configurable to” can include generic structure (e.g., generic circuitry) that is manipulated by software and/or firmware (e.g., a field programmable gate array (FPGA) or a general -purpose processor executing software) to operate in manner that is capable of performing the task(s) at issue. “Configured to” may also include adapting a manufacturing process (e.g., a semiconductor fabrication facility) to fabricate devices (e.g., integrated circuits) that are adapted to implement or perform one or more tasks. “Configurable to” is expressly intended not to apply to blank media, an unprogrammed processor or unprogrammed generic computer, or an unprogrammed programmable logic device, programmable gate array, or other unprogrammed device, unless accompanied by programmed media that confers the ability to the unprogrammed device to be configured to perform the disclosed function(s).

[0118] The foregoing description, for the purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the embodiments and its practical applications, to thereby enable others skilled in the art to best utilize the embodiments and various modifications as may be suited to the particular use contemplated. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the present disclosure is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

[0119] The following examples are illustrative only and may be combined with other examples or teachings described herein, without limitation.

[0120] Example 1 : A method, performed by a first base station communicatively coupled to a first set of base stations that are equipped for far-field wireless power transfer, the method comprising: performing 506 a wireless power transfer measurement operation to identify a second set of base stations for a second active-coordination (ACS), the second ACS transferring power between the second ACS and a user equipment (UE), and the second set of base stations comprises a second base station; transmitting 514 a first message, to the UE, indicating a set of frequencies and a set of time slots for power transfer from the second ACS to the UE; and transmitting 509 a second message, to the second base station, indicating the second set of base stations in the second ACS.

[0121] Example 2: The method of example 1, wherein the second message further indicates the set of frequencies and the set of time slots for power transfer from the second ACS to the UE.

[0122] Example 3: The method of any of examples 1-2, wherein the first message further indicates a set of waveforms or a set of beam identities for power transfer from the second ACS to the UE.

[0123] Example 4: The method of any of examples 1-3, further comprising: updating the second ACS, wherein updating the second ACS comprises transmitting a fourth message to the second base station indicating a request to perform one or more of: adding a new base station to the second ACS; or removing a previous base station from the second ACS.

[0124] Example 5: The method of example 4, wherein the updating the second ACS comprises one or more of: determining that a power transfer rate between at least one base station of the second ACS has dropped below a threshold power transfer rate; receiving a request for wireless power transfer from the UE; determining that a power level of the UE is above a threshold power level; or determining that a UE has moved.

[0125] Example 6: The method of example 4, wherein the updating the second ACS comprises one or more of: receiving one or more messages from the UE indicating the power transfer rate; receiving one or more messages from the UE indicating that the power level of the UE is above the threshold power level; or receiving one or more messages from the UE indicating that the UE has moved. [0126] Example 7: The method of any of examples 1-6, wherein the wireless power transfer measurement operation is performed in response to receiving a request from the UE for wireless power transfer.

[0127] Example 8: The method of any of examples 1-7, wherein transmitting 509 the second message to the second base station is via an Xn interface.

[0128] Example 9: The method of any of examples 1-8, wherein the performing the wireless power transfer measurement operation further comprises: transmitting 604 a third message, to the UE, instructing the UE to transmit a wireless power transfer reference signal.

[0129] Example 10: The method of any of examples 1-9, wherein the performing the wireless power transfer measurement operation further comprises: receiving 610, 612, 614 from a plurality of base stations, a set of measurement reports wherein the set of measurement reports indicate at least one signal quality parameter of the wireless power transfer reference signal detected by the plurality of base stations.

[0130] Example 11: The method of example 10, wherein performing the wireless power transfer measurement operation comprises: selecting 508 the second set of base stations from the plurality of base stations based on the set of measurement reports.

[0131] Example 12: The method of any of examples 1-8, wherein the performing the wireless power transfer measurement operation further comprises: transmitting 505 a plurality of messages to a plurality of base stations instructing the plurality of base stations to transmit a plurality of wireless power transfer reference signals.

[0132] Example 13: The method of any of examples 1-8 and 12, wherein the performing the wireless power transfer measurement operation further comprises: receiving 712 from the UE, at least one measurement report indicating a set of signal quality parameters of the plurality of reference signals detected by the UE.

[0133] Example 14: The method any of examples 1-8 and 12-13, further comprising: selecting 508 the second set of base stations from the plurality of base stations based on at least one measurement report. [0134] Example 15: The method of example 1, further comprising: establishing 502 a first ACS for communicating user plane data between the first ACS and the UE, the first ACS comprising the first set of base stations and the first set of base stations including the first base station.

[0135] Example 16: The method any of examples 1-15, wherein the performing the wireless power transfer measurement operation further comprises: selecting the second base station from the second set of base stations.

[0136] Example 17: A method, performed by a first base station, the method comprising: receiving 505, from a second base station, a request to perform a wireless power transfer measurement operation with a user equipment (UE); in response to the request, performing 506 the wireless power transfer measurement operation with the UE; receiving 509, from the second base station, a first message indicating a first set of base stations for a first active-coordination-set (ACS) for power transfer to the UE from the first ACS, wherein the first set of base stations comprises the first base station; and wirelessly transferring power 515 to the UE from the first set of base stations of the first ACS.

[0137] Example 18: The method of example 17, wherein the first message further indicates a set of frequencies, a set of time slots, a set of waveforms, or a set of beam identities for power transfer from the first ACS to the UE.

[0138] Example 19: The method any of examples 17-18, wherein wirelessly transferring power to the UE from the first set of base stations comprises: forwarding at least a portion of the set of frequencies, the set of time slots, the set of waveforms, or the set of beam identities to other base stations in the first set of base stations.

[0139] Example 20: The method of any of examples 17-19, further comprising: receiving, via the second base station, a third message indicating that the first ACS should be updated; and updating the first ACS, wherein updating the first ACS comprises one or more of: adding 808 a new base station to the first ACS; or removing 810 a previous base station from the first ACS.

[0140] Example 21: The method of any of examples 17-20, wherein the UE and the first ACS refrain from jointly-communicating user plane data. [0141] Example 22: The method of any of examples 17-21, wherein a second ACS for jointly- communicating user plane data with the UE comprises the second base station.

[0142] Example 23: The method of any of examples 17-22, wherein the first ACS and second ACS comprise at least one common base station.

[0143] Example 24: The method of any of examples 17-23, wherein the first ACS and second ACS lack common base stations.

[0144] Example 25: The method of any of examples 17-24, wherein the first ACS jointly- transmits radio-frequency (RF) signals at a first frequency band and the second ACS jointly - transmits RF signals at a second frequency band non-overlapping with the first frequency band.

[0145] Example 26: The method of any of examples 17-25, further comprising: transmitting radio frequency signals to the UE to provide power to the UE via the radiofrequency signals.

[0146] Example 27: The method of any of examples 17-26, wherein performing the wireless power transfer measurement operation further comprises: receiving 702, via the second base station, a request for the first set of base stations to transmit a set of reference signals on a second set of time slots; and forwarding 704 the request to the other base stations in the first set of base stations; and transmitting a reference signal on a time slot of the second set of time slots.

[0147] Example 28: The method of any of examples 17-27, wherein performing the wireless power transfer measurement operation further comprises: receiving 602 a second message indicating a second set of time slots when the UE will transmit a reference signal; forwarding 604 an indicator of the second set of time slots to other base stations of the first

ACS; and measuring 608 a signal quality parameter of the reference signal received on the second set of time slots.

[0148] Example 29: The method of any of examples 17-26 and 28, wherein the performing the wireless power transfer measurement operation further comprises: receiving a set of measurement reports from the other base stations of the first ACS, wherein the set of measure reports indicate a set of signal quality parameters of the reference signal received by the other base stations of the first ACS; and transmitting a message indicative of the set of signal quality parameters of the reference signal to the second base station.

[0149] Example 30: A base station, comprising: one or more radio frequency (RF) modems; a processor coupled to the one or more RF modems; and at least one memory stonng executable instructions, the executable instructions to manipulate at least one of the processor or the one or more RF modems to perform the method of any of examples 1-29.

[0150] Example 31 : A method, performed by a user equipment (UE), the method compnsing: transmitting a request for far-field wireless power transfer; performing a wireless power transfer measurement operation to identify a one or more base stations for a second active-coordination-set (ACS), wherein the second ACS is for power transfer from the second ACS to the UE, and the second set of base stations comprises a second base station; receiving, via a first ACS, a first message indicating a set of frequencies and a set of time slots for power transfer from the second ACS to the UE; and receiving power wirelessly from one or more of the second set of base stations of the second ACS.

[0151] Example 32: The method of example 31, wherein the first message further indicates a second set of base stations for the second ACS.

[0152] Example 33: The method of any of examples 31-32, wherein the performing the wireless power transfer measurement operation further comprises one or more of: receiving a second message instructing the UE to transmit a reference signal, or receiving a third message indicating a set of time slots for detecting a set of reference signals from a plurality of base stations.

[0153] Example 34: The method of any of examples 31-33, further comprising: transmitting a measurement report indicating a set of received signal quality parameters for a set of reference signals.

[0154] Example 35: The method of any of examples 31-34, further comprising: transmitting a message indicating that the second ACS should be updated, wherein updating the second ACS comprises one or more of: adding a new base station to the second ACS; or removing a previous base station from the second ACS.

[0155] Example 36: The method of any of examples 31-35, wherein the UE and the second ACS refrain from jointly-communicating user plane data.

[0156] Example 37: The method of any of examples 31-36, wherein the first ACS and second ACS comprise at least one common base station.

[0157] Example 38: The method of any of examples 31-37, wherein the first ACS and second ACS lack common base stations.

[0158] Example 39: The method of any of examples 31-38, wherein the receiving the first message comprises: receiving the first message at a first frequency band, wherein the receiving power wirelessly comprises receiving the power wirelessly at a second frequency band non-overlapping with the first frequency band.

[0159] Example 40: The method of any of examples 34-39, wherein a first received signal quality parameter of the set of received signal quality parameters achieves a predefined threshold value.

[0160] Example 41 : A user equipment, comprising: one or more radio frequency (RF) modems; a first antenna array to communicate data; a second antenna array to receive wireless power; a battery to store the wireless power; and a processor coupled to the one or more RF modems; and at least one memory storing executable instructions, the executable instructions to manipulate at least one of the processor or the one or more RF modems to perform the method of any of examples 33-40.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A method, performed by a first base station communicatively coupled to a first set of base stations that are equipped for far-field wireless power transfer, the method comprising: performing 506 a wireless power transfer measurement operation to identify a second set of base stations for a second active-coordination (ACS), the second ACS transferring power between the second ACS and a user equipment (UE), and the second set of base stations comprises a second base station; transmitting 514 a first message, to the UE, indicating a set of frequencies, a set of time slots, and a set of wavefomis for far-field power transfer from the second ACS to the UE; and transmitting 509 a second message, to the second base station, indicating the second set of base stations in the second ACS.

2. The method of claim 1, wherein the second message further indicates the set of frequencies, the set of time slots, and the set of waveforms for power transfer from the second ACS to the UE.

3. The method of any of claims 1-2, wherein the first message further indicates a set of waveforms or a set of beam identities for power transfer from the second ACS to the UE.

4. The method of any of claims 1-3, further comprising: updating the second ACS, wherein updating the second ACS comprises transmitting a fourth message to the second base station indicating a request to perform one or more of: adding a new base station to the second ACS; or removing a previous base station from the second ACS.

5. The method of claim 4, wherein the updating the second ACS comprises one or more of: determining that a power transfer rate between at least one base station of the second

ACS has dropped below a threshold power transfer rate; receiving a request for wireless power transfer from the UE; determining that a power level of the UE is above a threshold power level; or determining that a UE has moved.

6. The method of claim 4, wherein the updating the second ACS compnses one or more of: receiving one or more messages from the UE indicating the power transfer rate; receiving one or more messages from the UE indicating that the power level of the UE is above the threshold power level; or receiving one or more messages from the UE indicating that the UE has moved.

7. The method of any of claims 1-6, wherein the wireless power transfer measurement operation is performed in response to receiving a request from the UE for wireless power transfer.

8. The method of any of claims 1-7, wherein the performing the wireless power transfer measurement operation further comprises: transmitting 604 a third message, to the UE, instructing the UE to transmit a wireless power transfer reference signal; and receiving 610, 612, 614 from a plurality of base stations, a set of measurement reports wherein the set of measurement reports indicate at least one signal quality parameter of the wireless power transfer reference signal detected by the plurality of base stations.

9. The method of any of claims 1-7, wherein the performing the wireless power transfer measurement operation further comprises: transmitting 505 a plurality of messages to a plurality of base stations instructing the plurality of base stations to transmit a plurality of wireless power transfer reference signals; and receiving 712 from the UE, at least one measurement report indicating a set of signal quality parameters of a plurality of reference signals detected by the UE.

10. A method, performed by a user equipment (UE), the method compnsing: transmitting, to a first base station, a request for far-field wireless power transfer; performing a wireless power transfer measurement operation to identify a one or more base stations for a second active-coordination-set (ACS), wherein the second ACS is for power transfer from the second ACS to the UE, and the second set of base stations comprises a second base station; receiving, from the first base station, a first message indicating a set of frequencies, a set of time slots, and a set of waveforms for far-field power transfer from the second ACS to the UE; and receiving power wirelessly from one or more of the second set of base stations of the second ACS in accordance with the first message.

11. The method of claim 10, wherein the performing the wireless power transfer measurement operation further comprises one or more of: receiving a second message instructing the UE to transmit a reference signal; or receiving a third message indicating a set of time slots for detecting a set of reference signals from a plurality of base stations.

12. The method of any of claims 10-1 1 , wherein the UE and the second ACS refrain from jointly-communicating user plane data.

13. The method of any of claims 10-12, wherein a first ACS and second ACS comprise at least one common base station.

14. The method of any of claims 10-13, wherein the receiving the first message comprises: receiving the first message at a first frequency band, and wherein the receiving power wirelessly comprises: receiving the power wirelessly at a second frequency band non-overlapping with the first frequency band.

15. An apparatus comprising: a wireless transceiver; a processor; and computer-readable storage media comprising instructions that, responsive to execution by the processor, direct the apparatus to perform a method as recited in any one of claims 1 to 14.