Wireless power-feeding system and method

Abstract

A wireless power-feeding system 100 comprises a base station 500 having an RU 52 that transmits and receives data to and from at least one among a plurality of terminals 700 and that wirelessly feeds power to the plurality of terminals 700. The base station 500 comprises a wireless resource reservation control function unit 51A that allocates wireless resources of the base station 500 at a prescribed distribution ratio to the transmission and reception of data between the RU 52 and at least one terminal 700 and to the wireless feeding of power by the RU 52 to the plurality of terminals 700. On the basis of the result of the allocation of the wireless resources by the wireless resource reservation control function unit 51A, the RU 52 transmits and receives data to and from a terminal 700 and wirelessly feeds power to the terminals.

Description

Wireless power supply system and method

[0001] The present disclosure relates to a wireless power supply technology that utilizes wireless communication.

[0002] In recent years, Society 5.0 has been proposed, which aims to realize a smart society by installing a huge number of IoT terminals in various places in everyday spaces and using a wide variety of sensing data (see Non-Patent Document 1).

[0003] To realize Society 5.0, a huge number of IoT devices will be required, and one of the problems is how to supply power to the devices. Energy harvesting (EH) technology, which gathers energy from the surrounding environment and uses it as power, has attracted attention as a technology to solve this problem (see Non-Patent Document 2).

[0004] Non-Patent Document 3 proposes a wireless power supply using wireless communication, which is one of the EH technologies and can stably supply power in various places. Non-Patent Document 4 also discloses a terminal that performs intermittent operation, periodically repeating normal operation and standby operation. A terminal that performs such intermittent operation can effectively utilize the minute power generated by wireless power supply.

[0005] On the other hand, to perform such wireless power supply, it is necessary to consider the radio resources of the base station. In particular, it is necessary to consider that the radio resources of the base station are already being used for transmitting and receiving data between the base station and the terminal. For example, wireless communication standards such as 4G and 5G adopt a multiple access method using Orthogonal Frequency Division Multiple Access (OFDMA) / Time Division Multiple Access (TDMA) (see Non-Patent Document 5). Non-Patent Document 3 discloses a technique for utilizing RBs (Resource Blocks) in the OFDMA / TDMA method not only for wireless communication (data transmission and reception) but also for wireless power supply. Furthermore, Non-Patent Documents 6 and 7 disclose reservation techniques for reserving radio resources of a base station in advance for transmitting and receiving data that requires low latency and high reliability.

[0006] Cabinet Office, "Society 5.0", Internet, <https: / / www8.cao.go.jp / cstp / society5_0 / > Energy Harvesting Consortium, "What is Energy Harvesting?", Internet, <https: / / www.nttdata-strategy.com / ehc / about / > Y. Nakamoto, N. Hasegawa, T. Hirakawa and Y. Ohta, "A Study on OFDM Modulation Suitable for Wireless Power Transfer," 2022 Wireless Power Week (WPW), Bordeaux, France, 2022, pp. 21-24, doi: 10.1109 / WPW54272.2022.9853969. ABLIC Inc., "What is Intermittent Operation?", Internet, <https: / / www.ablic. com / jp / semicon / products / rtc / intermittent-operation / >NTT Docomo, "5G Wireless Access Technology," Internet, <https: / / www.docomo.ne.jp / binary / pdf / corporate / technology / rd / technical_journal / bn / vol23_4 / vol23_4_004jp.pdf> Silex Technology, Inc., "5G Mobile Phones (2)," Internet, <https: / / www.silex.jp / blog / wireless / 2021 / 06 / 5g2-4g-lte5g. html> Takeshi Hattori, Masayoshi Fujioka, "Continuation of 5G Textbook: From NSA / SA to 6G", pp. 93-94 Shuhei Yamanokuchi, Toshiya Asakura, Masashi Yoshida, Kenjiro Nishikawa, J-STAGE, "Proceedings of the Kyushu Branch Joint Conference of the Institutes of Electrical Engineers, Prototype and Evaluation of a 1 GHz Band Wideband Rectifier Using a Multistage Matching Circuit", Internet, <https: / / www. jstage. jst. go. jp / article / jceeek / 2021 / 0 / 2021_245 / _article / -char / ja / >,<https: / / www. jstage. jst. go. jp / article / jceeek / 2021 / 0 / 2021_245 / _pdf>,

[0007] When the amount of wireless communication traffic is high or when there are too many requests for wireless power supply, it is not possible to satisfy the wireless power supply requests and provide stable wireless power supply, even if wireless power supply is provided using wireless resources remaining after data transmission and reception as in Non-Patent Document 3. Furthermore, even with the techniques disclosed in Non-Patent Documents 6 and 7, wireless resources are preferentially secured for data transmission and reception, and therefore stable wireless power supply cannot be provided.

[0008] On the other hand, if wireless resources are simply reserved preferentially for wireless power supply, there may be times when many data communication requests cannot be met, leading to a deterioration in existing communication quality and frequent quality fluctuations, and lowering the satisfaction of communication users.

[0009] Therefore, an object of the present disclosure is to provide a wireless power supply system that can achieve both stable wireless power supply and high communication quality by allocating and reserving wireless resources in advance in a balanced manner for wireless power supply and data transmission / reception.

[0010] In order to achieve the above object, the wireless power feeding system of the present disclosure employs a method of allocating wireless resources of a base station to data transmission / reception and wireless power feeding at a predetermined allocation ratio.

[0011] Specifically, the wireless power supply system of the present disclosure is a wireless power supply system including a base station having a wireless communication unit that transmits and receives data to at least one of a plurality of terminals and wirelessly supplies power to the plurality of terminals, wherein the base station includes a wireless resource reservation unit that allocates wireless resources of the base station to the transmission and reception of the data between the wireless communication unit and the at least one terminal and the wireless power supply of the wireless communication unit to the plurality of terminals in a predetermined allocation ratio, and the wireless communication unit transmits and receives the data to and receives the data from the at least one terminal and supplies wireless power to the plurality of terminals based on the result of the wireless resource allocation by the wireless resource reservation unit.

[0012] Specifically, the wireless power supply method of the present disclosure allocates wireless resources of the base station at a predetermined allocation ratio to data transmission and reception between a base station and at least one of a plurality of terminals, and wireless power supply from the base station to the plurality of terminals, and performs the data transmission and reception between the at least one terminal and the wireless power supply to the plurality of terminals based on the result of the wireless resource allocation.

[0013] According to this, by wirelessly supplying power based on a predetermined distribution ratio while taking into consideration the existing communication quality, it is possible to maintain a stable power supply and stable communication quality, and it is also possible to respond to immediate power supply requests without significantly reducing the satisfaction of communication users.

[0014] Furthermore, when transmitting and receiving data and supplying wireless power based on the result of the allocation of the wireless resources by the wireless resource reservation unit, if there are surplus wireless resources allocated for either the transmission and reception of data or the wireless power supply, the wireless communication unit may use the surplus wireless resources for the other one.

[0015] This allows for effective use of wireless resources during actual wireless power supply and communication.

[0016] Furthermore, the terminal may have frequency characteristics that increase internal power conversion efficiency when wirelessly powered at a predetermined frequency, the wireless resource reservation unit may allocate the wireless resources based on the frequency characteristics of the terminal, and the wireless communication unit may wirelessly power the terminal at a frequency that increases power conversion efficiency.

[0017] This allows for maximizing power supply efficiency. Also, by taking into account the frequency characteristics of the terminal, it is possible to reduce the amount of wireless resources consumed.

[0018] The above disclosures can be combined as much as possible.

[0019] According to the present disclosure, wireless resources are allocated in advance in a balanced manner for wireless power supply and data transmission / reception, and then reserved and secured, thereby achieving both stable wireless power supply and communication quality.

[0020] FIG. 1 is a diagram illustrating an overview of a wireless power feeding system according to a first embodiment of the present disclosure. FIG. 2 is a diagram illustrating an overall configuration of a wireless power feeding system according to the first embodiment of the present disclosure. FIG. 3 is a diagram illustrating a resource allocation method of a wireless power feeding system according to the first embodiment of the present disclosure. FIG. 4 is a diagram illustrating a configuration of a wireless power feeding system according to a second embodiment of the present disclosure. FIG. 5 is a diagram illustrating a configuration of a wireless power feeding system according to a third embodiment of the present disclosure. FIG. 6 is a diagram illustrating a resource allocation reservation method of a wireless power feeding system according to a fourth embodiment of the present disclosure. FIG. 7 is a diagram illustrating a resource allocation reservation method of a wireless power feeding system according to a fifth embodiment of the present disclosure. FIG. 8 is a diagram illustrating a resource allocation reservation method of a wireless power feeding system according to a sixth embodiment of the present disclosure. FIG. 9 is a diagram illustrating a resource allocation reservation method of a related wireless power feeding system. FIG. 10 is a diagram illustrating a resource allocation reservation method of a wireless power feeding system according to a seventh embodiment of the present disclosure. FIG. 11 is a sequence diagram of a wireless power feeding system according to an eighth embodiment of the present disclosure.

[0021] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below. These implementation examples are merely illustrative, and the present disclosure can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art. Note that components with the same reference numerals in this specification and drawings indicate the same components.

[0022] First Embodiment A wireless power feeding system 100 according to an embodiment of the present disclosure will be described with reference to Fig. 1 to Fig. 3. In Fig. 1, an overview of the wireless power feeding system 100 will be described.

[0023] The wireless power supply system 100 wirelessly supplies power based on requests from a terminal, other functional units, or external devices. The terminal is, for example, an IoT terminal. The wireless power supply system 100 allocates wireless resources to external wireless requests with priority over communication requests (data transmission / reception requests), and allocates the remaining wireless resources to the communication requests. The wireless power supply system 100 reserves wireless resources for power supply in advance, taking into account the frequency characteristics of the terminal requiring power supply, and actually supplies power based on the reservation, thereby achieving both highly efficient communication (data transmission / reception) and power supply. Figure 1 shows the minimum functions required to implement such a wireless resource allocation method based on a 5G wireless network. Furthermore, the wireless resource allocation method of the present disclosure is applicable to any communication standard that allows the wireless resource reservation function.

[0024] The wireless power supply system 100 mainly includes a 5G core 200, a wireless power supply controller 300, a RAN (Radio Access Network) controller 400, and a base station 500. The base station 500 includes a CU / DU (Central Unit / Distributed Unit) 51 and an RU (Radio Unit) 52. The 5G core 200 performs relay processing of communication data transmitted from the base station 500 (CU / DU 51). The RU 52 functions as a "wireless communication unit."

[0025] The wireless power feeding controller 300 includes a wireless power feeding request control function unit 31. The wireless power feeding request control function unit 31 calculates how much wireless power is required from information indicating which terminal currently requires how much power for a group of terminals under the control of the RU 52 of the base station 500. The wireless power feeding request control function unit 31 transmits the calculation result to the RAN controller 400 as a wireless power feeding request. The function of the wireless power feeding controller 300 may be provided within the RAN controller 400. Note that in this embodiment, the group of terminals under the control of the RU 52 is omitted for simplicity. Furthermore, the wireless power feeding request control function unit 31 obtains information indicating how much power the terminal currently requires, directly from the terminal requiring wireless power feeding or indirectly via another function unit.

[0026] The RAN controller 400 includes a wireless power feeding request relay function unit 41. The wireless power feeding request relay function unit 41 has a function of relaying a wireless power feeding request sent from the wireless power feeding controller 300 to the base station 500. It is optional whether or not to provide the wireless power feeding request relay function unit 41. If the wireless power feeding request relay function unit 41 is not provided, the wireless power feeding request is transmitted directly from the wireless power feeding controller 300 to the base station 500.

[0027] The CU / DU 51 includes a radio resource reservation control function unit 51A, an RB (Resource Block) scheduling processing function unit 51B, and a communication request function unit 51C. The communication request function unit 51C has a function of transferring communication requests generated in the base station 500 to the RB scheduling processing function unit 51B. The RB scheduling processing function unit 51B has a scheduling function of allocating which of the radio resources possessed by the base station 500 to which input communication requests and wireless power supply requests. The radio resource reservation control function unit 51A has a reservation function of preferentially allocating part or all of the radio resources possessed by the base station 500 for wireless power supply and wireless communication. The processing result by the radio resource reservation control function unit 51A is taken into consideration when the RB scheduling processing function unit 51B performs scheduling. Specifically, part or all of the wireless resources are allocated preferentially to wireless power supply and wireless communication, and appropriate wireless resources are allocated to achieve a good balance between communication (data transmission and reception) and power supply. The wireless resource reservation control function unit 51A functions as a "wireless resource reservation unit."

[0028] The RU 52 includes a radio transmission / reception function unit 52 A. The RU 52 realizes communication or power supply using appropriate radio resources based on the processing result of the RB scheduling processing function unit 51 B.

[0029] As described above, the wireless power supply system 100 is a wireless power supply system including a base station 500 having an RU 52 that transmits and receives data to at least one of a plurality of terminals 700 and wirelessly supplies power to the plurality of terminals 700, wherein the base station 500 includes a wireless resource reservation control function unit 51A that allocates the wireless resources of the base station 500 at a predetermined allocation ratio to the transmission and reception of data between the RU 52 and at least one of the terminals 700 and the wireless power supply to a plurality of terminals within the coverage area of ​​the RU 52, and the RU 52 transmits and receives data to at least one of the terminals 700 and wirelessly supplies power to the plurality of terminals 700 based on the result of the wireless resource allocation by the wireless resource reservation control function unit 51A.

[0030] According to this embodiment, it is possible to achieve a good balance between communication and power supply by using appropriate wireless resources while preferentially allocating part or all of the wireless resources to wireless power supply and wireless communication. In this way, stable and efficient power supply and communication quality can be flexibly maintained, so that the satisfaction of communication users is not reduced and immediate power supply requests can be accommodated. As a result, it is possible to increase the number of terminals that satisfy the intermittent operation cycle without excessively impeding communication.

[0031] Next, the overall configuration of a wireless power supply system 100 for realizing this embodiment will be described with reference to Fig. 2. For simplicity, terminals under the control of the RU 52 are also omitted from Fig. 2.

[0032] The wireless power supply system 100 is composed of an external data network 600, a 5G core 200, one or more wireless power supply controllers 300, a RAN controller 400, one or more base stations 500, and a group of terminals. The external data network 600 is a network that delivers communication data sent from the 5G core 200 to an appropriate destination. This corresponds to the conventional Internet or a private network. The base station 500 also includes one or more RUs 52. Although omitted due to space limitations, the multiple RUs 52 cover the same group of terminals.

[0033] In this way, there may be provided a plurality of each of the wireless power supply controller 300, the base station 500, and the RU 52. Although the following description may be given of a single wireless power supply controller 300, the base station 500, and the RU 52, the technology of the present disclosure also functions without any problems in a configuration in which a plurality of each is provided.

[0034] When a plurality of wireless power feeding controllers 300 are provided, the wireless power feeding request relay function unit 41 of the RAN controller 400 may collectively relay wireless power feeding requests from the plurality of wireless power feeding controllers 300, or may independently relay a wireless power feeding request immediately after receiving it from each wireless power feeding controller 300. Note that the wireless power feeding request relay function unit 41 aggregates a plurality of wireless power feeding requests and transmits the wireless power feeding requests collectively to a function unit of the base station 500, thereby reducing the load on the base station 500.

[0035] The external network 600 is a network that has the function of delivering communication data sent from the 5G core 200 to an appropriate destination. This corresponds to the conventional Internet or a private network.

[0036] The 5G core 200 is a core network in the 5G standard, and relays communication data sent from the base station 500 to an external data network 600 or other base stations 500.

[0037] The wireless power feeding controller 300 is a device that identifies a terminal 700 that requires wireless power feeding and transmits a wireless power feeding request instruction to each base station 500 so that the terminal 700 is supplied with appropriate power. The wireless power feeding controller 300 may be the same as an existing wireless power feeding controller. The functions of the wireless power feeding controller 300 may be transferred to the RAN controller 400, and the controllers may be integrated and centralized.

[0038] RAN controller 400 is a device that manages the sleep of each subordinate base station 500. There may be a plurality of base stations 500 managed by RAN controller 400, or there may be only one base station 500.

[0039] The base station 500 is a communication device that provides a wireless access network and enables subordinate terminals 700 to transmit data via wireless communication. The CU / DU / RU (Central Unit / Distributed Unit / Radio Unit) of the base station 500 may be separate or integrated. Furthermore, there may be multiple RUs 52 or only one RU 52. When multiple RUs 52 are present, their coverage areas may or may not overlap. Furthermore, multiple base stations 500 may cover the same area or different areas. In summary, there are no limitations on the number or configuration of the base stations 500. The detailed configuration and functions of the base station 500 as an example will be described later.

[0040] Furthermore, the base station 500 does not necessarily need to transmit and receive data to and from all of the subordinate terminals 700. In other words, the base station 500 is configured to wirelessly feed power not only to the terminals 700 that directly transmit and receive data to and from the base station 500, but also to wirelessly feed power to the terminals 700 that do not directly transmit and receive data to and from the base station 500.

[0041] Next, the resource allocation method of this embodiment will be described with reference to Fig. 3. The figure shows wireless resources with the horizontal axis representing frequency and the vertical axis representing time. A box filled in gray indicates that a reservation for wireless communication (traffic) or an actual allocation has been made. A box hatched with diagonal lines from the lower left to the upper right indicates that a reservation for wireless power supply or an actual allocation has been made. A box that is not filled in or hatched indicates that a resource is available.

[0042] Furthermore, dotted and filled or hatched frames indicate that wireless communication or wireless power supply is reserved, whereas solid and filled or hatched frames indicate that wireless communication or wireless power supply is allocated.

[0043] In this embodiment, it is assumed that requests for wireless communication and wireless power supply are made corresponding to a 4x5 grid, as shown in the left part of the figure. First, (A) when wireless resources are allocated with priority given to wireless communication, as in the existing technology (see Non-Patent Document 3), wireless power supply is allocated to the wireless resources remaining after allocating wireless resources to wireless communication. As a result, a large number of unsatisfied wireless power supply requests occur. In this way, when wireless resources are allocated with priority given to wireless communication, stable wireless power supply cannot be performed. In particular, during time periods with high communication traffic, most of the wireless resources are consumed by communication resources. This leads to problems such as, for example, being unable to respond to wireless power supply requests from terminals that urgently require power supply, and being unable to provide stable power supply.

[0044] Furthermore, when wireless resources are allocated with priority given to wireless power supply (B), the remaining wireless resources after allocating wireless resources to wireless power supply are allocated to wireless communication. As a result, a large number of unsatisfied wireless communication requests occur. In this way, when wireless resources are allocated with priority given to wireless power supply, there are moments when communication quality becomes unstable and extremely degraded, which poses a problem of reduced satisfaction among communication users.

[0045] In contrast to these, (C) in the present embodiment, radio resources are allocated in a balanced manner between wireless communication and wireless power supply according to a predetermined allocation ratio determination algorithm. Specifically, in the present embodiment, radio resources for wireless power supply are allocated according to the frequency characteristics of the terminal requiring wireless power supply. This makes it possible to maintain stable power supply and stable communication quality, and therefore to respond to immediate power supply requests without reducing the satisfaction of communication users. Furthermore, because radio resources with high power supply efficiency are used, power supply requests can be satisfied with fewer radio resources than in the above cases (A) and (B). Furthermore, the allocation ratio of radio resources may be dynamically changed depending on the usage case. Specifically, the allocation ratio may be changed to 50:50 or 6:4 depending on the time of day.

[0046] As described above, the wireless power feeding system 100 according to the present embodiment has a wireless resource advance reservation function that uses the function of reserving and securing wireless resources in advance of the base station 500 to preferentially secure wireless resources for wireless power feeding in advance and use only the remaining wireless resources for communication. Furthermore, the wireless power feeding system 100 considers the frequency characteristics in RF-DC (Radio Frequency-Direct Current) conversion of the terminal requiring power feeding as the location of the wireless resources to be reserved for wireless power feeding and wireless communication.

[0047] Second Embodiment Next, a wireless power feeding system 100 according to a second embodiment will be described with reference to Fig. 4. The wireless power feeding system 100 according to the second embodiment basically has the same configuration as that described in the first embodiment. Specifically, the wireless power feeding system 100 includes a wireless power feeding controller 300, a RAN controller 400, a base station 500, and a terminal 700. Below, the functions of each functional unit will be mainly described in more detail.

[0048] The wireless power feeding controller 300 includes a wireless power feeding request control function unit 31. The wireless power feeding request control function unit 31 collects information indicating the amount of power feeding required by each terminal from a group of wireless power feeding terminals 700 managed by the wireless power feeding controller 300, i.e., a group of wireless power feeding terminals 700 under a certain base station 500. The wireless power feeding controller 300 calculates the amount of wireless power feeding required from the collected information. The wireless power feeding controller 300 transmits the calculation result to the RAN controller 400 as a wireless power feeding request. The wireless power feeding request includes information such as power feeding terminal information, the required amount of power feeding, power feeding frequency characteristics, and the remaining time until intermittent operation. The functions of the wireless power feeding controller 300 may be provided within the RAN controller 400, or may be independent as in this embodiment.

[0049] The RAN controller 400 includes a wireless power feeding request relay function unit 41. The wireless power feeding request relay function unit 41 has a function of relaying a wireless power feeding request sent from the wireless power feeding controller 300 to the base station 500. It is optional whether or not to provide the wireless power feeding request relay function unit 41, and it is not necessarily required to provide the wireless power feeding request relay function unit 41. If the wireless power feeding request relay function unit 41 is not provided, the wireless power feeding request is sent directly from the wireless power feeding controller 300 to the base station 500.

[0050] The CU / DU 51 of the base station 500 includes a radio resource reservation control function unit 51A, an RB scheduling processing function unit 51B, and a communication request function unit 51C. The communication request function unit 51C has a function of transferring communication requests generated in intra-base station communication, inter-base station communication, and communication with an external data network (data transmission / reception) to the RB scheduling processing function unit 51B.

[0051] A currently known general RB scheduling processing function unit normally only allocates radio resources to input communication requests. In contrast, the RB scheduling processing function unit 51B according to this embodiment has a scheduling function that not only allocates radio resources to input communication requests but also controls which radio resources from the radio resources possessed by the base station 500 are to be allocated to wireless power supply requests. Here, since the radio resources of the base station 500 are finite, appropriate scheduling is required. The RB scheduling processing function unit 51B may allocate radio resources to communication requests and wireless power supply requests by time-division, or may allocate them by frequency-division, thereby mixing communication data and data for wireless power supply within the same time period. Specific scheduling methods will be described later.

[0052] The radio resource reservation control function unit 51A has a function of transmitting a request to the RB scheduling processing function unit 51B to preferentially allocate some or all of the radio resources possessed by the base station 500 for wireless power supply and wireless communication. Such a function unit is originally provided for communications that require low latency and high quality. In this embodiment, such a function is applied, and the radio resource reservation control function unit 51A is used to reserve radio resources for wireless power supply. General wireless communication quality changes depending on the reservation rate of radio resources for wireless power supply by the radio resource reservation control function unit 51A. The processing result by the radio resource reservation control function unit 51A is taken into consideration when the RB scheduling processing function unit 51B performs scheduling. In other words, the reservation by the radio resource reservation control function unit 51A is related to the scheduling by the RB scheduling processing function unit 51B.

[0053] The RU 52 of the base station 500 includes a radio transmission / reception function unit 52 A. The radio transmission / reception function unit 52 A actually performs radio transmission / reception in accordance with the allocation of radio resources determined by the RB scheduling processing function unit 51 B in the CU / DU 51.

[0054] The terminal 700 includes, as minimum functional units, a wireless power supply functional unit 71 and a communication functional unit 72. The wireless power supply functional unit 71 has a function of extracting power wirelessly from the RU 52. The communication functional unit 72 has a function of directly communicating with the RU 52. The communication functional unit 72 may communicate with the RU 52 of the base station 500 to send and receive data, or may communicate with an external access point other than the base station 500 to send and receive data. When the communication functional unit 72 communicates with an external access point other than the base station 500, the base station 500 only functions to provide power wirelessly to the terminal 700.

[0055] Furthermore, the terminal 700 may be a device equipped with multiple types of energy harvesting technologies that use communication radio waves as power, or may be a hybrid type with a battery. There are no particular limitations on the power supply configuration or operating configuration of the terminal 700, but it must at least have a built-in function for using communication radio waves as power. Regarding the power conversion of communication radio waves, the terminal 700 may use communication radio waves leaking to other terminals 700, or may use only communication radio waves addressed to itself. Furthermore, two types of communication radio waves are assumed: radio waves for transmitting and receiving data, and radio waves only for supplying power (wireless power supply).

[0056] According to this embodiment, a stable power supply and stable communication quality can be maintained, and therefore, an immediate power supply request can be accommodated without reducing the satisfaction of communication users.

[0057] [Third Embodiment] Next, a wireless power feeding system 101 according to a third embodiment will be described with reference to Fig. 5. Fig. 5 is a diagram illustrating the configuration of the wireless power feeding system 101. Unlike the above-described embodiments, the wireless power feeding system 101 does not include a RAN controller. Furthermore, the wireless power feeding system 101 includes multiple wireless power feeding controllers 300.

[0058] The functions of the other functional units are the same as those of the above embodiment. In this embodiment, a stable power supply and stable communication quality can be maintained, so that an immediate power supply request can be accommodated without reducing the satisfaction of communication users.

[0059] [Fourth Embodiment] Next, a radio resource allocation reservation method for a wireless power feeding system according to a fourth embodiment will be described with reference to Fig. 6. In this embodiment, as shown in the lower left of the figure, a radio resource allocation reservation method will be described for a case where there are many wireless power feeding requests and communication requests. First, in this embodiment, a radio resource reservation control function unit 51A reserves radio resources for wireless power feeding. Then, an RB scheduling processing function unit 51B allocates radio resources to wireless power feeding requests and communication requests, taking into account the reservation of radio resources for wireless power feeding by the radio resource reservation control function unit 51A. The same applies to the following embodiments.

[0060] In the reservation method shown in (A) of the figure, the radio resource reservation control function unit 51A reserves all radio resources for wireless power supply requests with priority. As a result, this reservation method results in a large number of unsatisfied communication requests. Since these unsatisfied communication requests are handled in the next time schedule, there is a possibility that the quality of wireless communication will be significantly impaired and the communication speed will be significantly reduced.

[0061] In the reservation method shown in (B) of the figure, the radio resource reservation control function unit 51A reserves radio resources for wireless power supply and communication while balancing the wireless power supply request and the communication request. The balancing method is performed by the radio resource reservation control function unit 51A. More specific processing by the radio resource reservation control function unit 51A will be described later. This balancing method does not necessarily satisfy both the wireless power supply request and the communication request completely, but it is possible to avoid a significant decrease in communication speed.

[0062] Fifth Embodiment Next, a method for reserving wireless resource allocation in a wireless power feeding system according to a fifth embodiment will be described with reference to Fig. 7. In this embodiment, as shown in the lower left of the figure, a method for reserving wireless resource allocation in a case where there are many wireless power feeding requests and few communication requests will be described.

[0063] In the reservation method shown in (A) of the figure, the radio resource reservation control function unit 51A reserves all radio resources for wireless power supply requests with priority. As described above, this reservation method results in a large number of unsatisfied communication requests. Since such unsatisfied communication requests are handled in the next time schedule, this may significantly impair the quality of wireless communication and cause a significant decrease in communication speed. However, when there are few communication requests, as in this embodiment, the impact on communication speed is small.

[0064] In the reservation method shown in (B) of the figure, the radio resource reservation control function unit 51A reserves radio resources for wireless power supply and communication while balancing wireless power supply requests and communication requests. The balancing method is performed by the radio resource reservation control function unit 51A. More specific processing by the radio resource reservation control function unit 51A will be described later. As a result, in this embodiment, since there are few communication requests, there are surplus radio resources for communication that have been reserved in advance, and the surplus radio resources can be used for wireless power supply.

[0065] In other words, when RU52 transmits and receives data and supplies power wirelessly based on the results of the wireless resource allocation by the wireless resource reservation control function unit 51A, if there are any surplus wireless resources allocated for either the transmission and reception of data or the wireless power supply, the surplus wireless resources are used for the other one.

[0066] Sixth Embodiment Next, a method for reserving wireless resource allocation in a wireless power feeding system according to a sixth embodiment will be described with reference to Fig. 8. In this embodiment, as shown in the lower left of the figure, a method for reserving wireless resource allocation in a case where there are few wireless power feeding requests and many communication requests will be described.

[0067] In the reservation method shown in (A) of the figure, the radio resource reservation control function unit 51A reserves all radio resources for wireless power supply requests with priority. As described above, this reservation method results in a large number of unsatisfied communication requests. These unsatisfied communication requests are handled in the next time schedule, which may significantly impair the quality of wireless communication and significantly reduce the communication speed. However, in this embodiment, since there are few wireless power supply requests, unused resources from the radio resources reserved for wireless power supply are allocated to communication, thereby reducing the impact on communication.

[0068] In the reservation method shown in (B) of the figure, the radio resource reservation control function unit 51A reserves radio resources for wireless power supply and communication while balancing wireless power supply requests and communication requests. The balancing method is performed by the processing of the radio resource reservation control function unit 51A. More specific processing of the radio resource reservation control function unit 51A will be described later. As a result, in this embodiment, since there are few wireless power supply requests, there are surplus radio resources for wireless power supply that have been reserved in advance, and the surplus radio resources can be used for wireless communication, thereby enabling highly efficient allocation.

[0069] In other words, when RU52 transmits and receives data and supplies power wirelessly based on the results of the wireless resource allocation by the wireless resource reservation control function unit 51A, if there are any surplus wireless resources allocated for either the transmission and reception of data or the wireless power supply, the surplus wireless resources are used for the other one.

[0070] [Seventh embodiment] Next, a detailed method for reserving radio resources for wireless power feeding by a radio resource reservation control function unit 51A of a wireless power feeding system according to a seventh embodiment will be described with reference to Fig. 9 . The method for reserving radio resources for wireless power feeding according to this embodiment is applicable to all of the embodiments described above. Fig. 9A is a diagram illustrating a resource allocation reservation method of a related wireless power feeding system. Fig. 9B is a diagram illustrating a resource allocation reservation method of a wireless power feeding system according to this embodiment.

[0071] Specifically, the terminal 700 has frequency characteristics that result in high internal power conversion efficiency when wirelessly powered at a specified frequency, the wireless resource reservation control function unit 51A allocates wireless resources based on the frequency characteristics of the terminal 700, and the RU 52 wirelessly powers the terminal 700 at a frequency that results in high power conversion efficiency.

[0072] In the related wireless power supply system shown in Fig. 9A, wireless resources for wireless power supply and wireless resources for communication are allocated simply according to the degree of need. This method is inefficient because it does not take into account the characteristics of the terminals that require wireless power supply.

[0073] In contrast, in the wireless power feeding system according to this embodiment shown in FIG. 9B, wireless resources are reserved taking into consideration the frequency characteristics of the terminal requiring wireless power feeding. Specifically, the terminal receiving wireless power feeding is equipped with an RF-DC converter, and since this RF-DC converter has frequency characteristics (see Non-Patent Document 8), the wireless resource reservation control function unit 51A reserves wireless resources in a frequency band with good frequency characteristics for power feeding. Then, by making the wireless signal have a large amplitude value at the frequency of the reserved wireless resource portion, it is possible to maximize power feeding efficiency. In this way, in this embodiment, it is possible to reduce the consumed wireless resources by taking into consideration the frequency characteristics of the terminal.

[0074] Eighth Embodiment Next, a processing sequence of a wireless power feeding system according to an eighth embodiment will be described with reference to Fig. 10. The processing sequence of the wireless power feeding system according to this embodiment is applicable to all of the embodiments described above.

[0075] Specifically, the wireless power supply method of the present disclosure allocates the wireless resources of the base station 500 at a predetermined allocation ratio to data transmission and reception between the base station 500 and at least one of the multiple terminals 700, and wireless power supply from the base station 500 to the multiple terminals 700, and performs the data transmission and reception between the base station 500 and at least one of the terminals 700 and wireless power supply to the multiple terminals 700 based on the result of the wireless resource allocation.

[0076] First, various communication sources 800 transmit communication requests (traffic) to the base station 500 for the terminals 700 under the control of the base station 500 (step S1).

[0077] At the same time as this or at a different time, a power supply request to the terminal 700 is transmitted to the base station 500 from the wireless power supply controllers 300 that manage the terminals 700 under the control of the base station 500 (step S2).

[0078] The RB scheduling processing function unit 51B of the base station 500 calculates and schedules the allocation of radio resources for communication or power supply in response to the communication request sent from the communication source 800 and the power supply request sent from the wireless power supply controller 300 (step S3). At this time, the RB scheduling processing function unit 51B takes into consideration the reservation status of radio resources by the radio resource reservation control function unit 51A.

[0079] The base station 500 performs wireless communication or wireless power feeding to the terminal 700 based on the scheduling by the RB scheduling processing function unit 51B (step S4). The wireless power feeding system repeats the above processing.

[0080] The device of the present invention can also be realized by a computer and a program, and the program can be recorded on a recording medium or provided via a network. The program of the present disclosure is a program for causing a computer to realize each function of the device according to the present disclosure, and a program for causing a computer to execute each procedure of the method executed by the device according to the present disclosure.

[0081] 31: Wireless power supply request control function unit 41: Wireless power supply request relay function unit 51: CU / DU 51A: Radio resource reservation control function unit 51B: RB scheduling processing function unit 51C: Communication request function unit 52: RU 52A: Radio transmission / reception function unit 71: Wireless power supply function unit 72: Communication function unit 100, 101: Wireless power supply system 200: 5G core 300: Wireless power supply controller 400: RAN controller 500: Base station 600: External data network 700: Terminal

Claims

1. A wireless power supply system comprising a base station having a wireless communication unit that transmits and receives data to and from at least one of a plurality of terminals and performs wireless power supply to the plurality of terminals, wherein the base station includes a wireless resource reservation unit that allocates the wireless resources of the base station to the transmission and reception of the data between the wireless communication unit and at least one of the terminals and the wireless power supply of the wireless communication unit to the plurality of terminals at a predetermined distribution ratio, and the wireless communication unit performs the transmission and reception of the data to and from at least one of the terminals and the wireless power supply to the plurality of terminals based on the allocation result of the wireless resources by the wireless resource reservation unit.

2. When the wireless communication unit performs the transmission and reception of the data and the wireless power supply based on the allocation result of the wireless resources by the wireless resource reservation unit, if there is remaining wireless resource allocated for either one of the transmission and reception of the data and the wireless power supply, the remaining wireless resource is used for the other one. The wireless power supply system according to claim 1.

3. The terminal has a frequency characteristic in which the internal power conversion efficiency is high for wireless power supply at a predetermined frequency. The allocation of the wireless resources by the wireless resource reservation unit is performed based on the frequency characteristic of the terminal, and the wireless communication unit performs wireless power supply to the terminal at a frequency with high power conversion efficiency. The wireless power supply system according to claim 1 or 2.

4. Allocate the transmission and reception of data between the base station and at least one of a plurality of terminals and the wireless power supply of the base station to the plurality of terminals to the wireless resources of the base station at a predetermined distribution ratio, and based on the allocation result of the wireless resources, perform the transmission and reception of the data to and from at least one of the terminals and the wireless power supply to the plurality of terminals. A wireless power supply method.

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