KR102062432B1 - Base station and method for wireless energy harvesting network system, and system comprising same - Google Patents

Abstract

An energy harvesting network system comprising a plurality of base stations and a plurality of wireless communication terminals, the energy harvesting network system comprising: a first base station performing data communication and power transmission via a wireless signal; a second base performing power supply via a wireless signal; A station and a radio communication terminal for receiving a radio signal from each of the first base station and the second base station, and converting the received radio signal into power energy based on the communication parameter information, the first base station and the second base station; The base station transmits a radio signal to a wireless communication terminal through a different channel during each time division period assigned to each in a time division manner, wherein the communication parameter information is determined based on network environment information. .

Description

BASE STATION AND METHOD FOR WIRELESS ENERGY HARVESTING NETWORK SYSTEM, AND SYSTEM COMPRISING SAME}

The present disclosure relates to an apparatus and method for optimizing energy efficiency of a wireless energy harvesting network that simultaneously performs wireless data communication and wireless power transfer.

With the recent development of IoT technology, wireless communication with wireless telecommunications is performed on sensor nodes including devices that use wireless communication such as users of cellular networks, Wi-Fi users, IP-Camera, TVs, washing machines, etc. There is a need for a next generation communication network system that provides power transfer and wireless power charging. In addition, in the field of wireless power charging technology, research on a wireless energy harvesting network that simultaneously performs information communication and wireless power charging has been conducted. In particular, the uncoupled wireless energy harvesting network is a network in which a power beacon is installed closer to the users than the transmitter to improve wireless power charging efficiency or speed. Accordingly, there is a need for a technology related to power control of how much transmission power each transmitter should have in order to optimize energy efficiency of an uncoupled wireless energy harvesting network.

An object of the present invention is to optimize energy efficiency of a wireless energy harvesting network that simultaneously performs wireless information communication and wireless power transmission.

According to an embodiment, a system includes an energy harvesting network system including a plurality of base stations and a plurality of wireless communication terminals, the first base station performing data communication and power transmission through a wireless signal, and power through a wireless signal. A second base station performing the supply, and a wireless communication terminal that receives a radio signal from each of the first base station and the second base station, and converts the received radio signal into power energy based on the communication parameter information. have. In addition, the first base station and the second base station included in the system transmits a radio signal to a wireless communication terminal through a different channel during each time division period allocated to each in a time division manner, and communication parameter information is a network It may be determined based on the environmental information.

In an energy harvesting network system, a base station for performing data communication and power transmission via a wireless signal includes a communication unit and a processor for transmitting and receiving a wireless signal, and the processor executes the at least one program. Determine communication parameters based on the network environment information, allocate time division intervals for each radio signal transmission to each of the base station and the uncoupled device for wireless power transmission, and to the wireless communication terminal during the time division intervals allocated to the base station. The wireless signal may be transmitted based on the communication parameter. Here, the non-coupling device may be a device for transmitting a radio signal for power transmission through a channel independent of the base station to the wireless communication terminal.

According to an embodiment, a wireless communication terminal for obtaining power energy and data from a wireless signal transmitted by a plurality of base stations includes a communication unit and a processor for transmitting and receiving wireless signals from the plurality of base stations, and the processor includes at least one program. By performing the operation, the communication unit receives information on a time interval in which the radio signals allocated for each of the plurality of base stations are transmitted and communication parameters, and transmits the plurality of bases based on the information on the time interval in which the radio signals are transmitted. A wireless signal transmitted through different channels may be received from each station, and the wireless signal received through the communication unit may be converted into power energy based on a communication parameter.

According to an embodiment, a method of performing data communication and power supply through a wireless signal by a base station included in an energy harvesting network system includes determining a communication parameter based on network environment information, a base station, and wireless power transmission. And allocating a time division interval for each wireless signal transmission to each of the uncoupled devices for transmitting the radio signal based on a communication parameter to the wireless communication terminal during the time division interval allocated to the base station.

A computer-readable recording medium according to another aspect includes a recording medium recording a program for executing the above method on a computer.

One embodiment of the present invention can optimize energy efficiency by controlling wireless signal transmission of a base station in a wireless energy harvesting network. An embodiment of the present invention may provide an environment-friendly communication network environment by optimizing power energy efficiency in a wireless energy harvesting network.

1 is a schematic diagram illustrating an example of an energy harvesting network system including a first base station, a second base station, and a wireless communication terminal, according to one embodiment of the disclosure.
2 is a diagram illustrating a configuration of a first base station and a second base station according to an embodiment of the present disclosure.
3 is a flowchart illustrating a method of operating a first base station that is a hybrid access point according to an embodiment of the present disclosure.
4A is a block diagram illustrating a configuration of a wireless communication terminal according to an embodiment of the present disclosure.
4B illustrates a flow of power of a wireless signal received in a wireless communication terminal according to an embodiment of the present disclosure.
5 is a flow diagram illustrating operation of a first base station to determine communication parameters to optimize energy efficiency in accordance with one embodiment of the present disclosure.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "electrically connected" with another element in between. . In addition, when a part is said to "include" a certain component, this means that it may further include other components, except to exclude other components unless otherwise stated.

The present disclosure relates to a method for optimizing energy efficiency in a wireless energy harvesting network system that simultaneously performs data communication and wireless power charging.

According to one embodiment of the present disclosure, a wireless energy harvesting network system may include a base station that additionally provides wireless power to increase the efficiency of wireless power charging. The wireless energy harvesting network system can increase the coverage of wireless power charging by including a plurality of base stations.

In addition, the method according to an embodiment of the present disclosure may optimize energy efficiency in an uncoupled wireless energy harvesting network system including a plurality of base stations. The method according to an embodiment of the present disclosure can alleviate the interference problem occurring in an uncoupled wireless energy harvesting network system including a plurality of base stations.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram illustrating an example energy harvesting network system including a first base station 100, a second base station 300, and a wireless communication terminal 200a, 200b, 200c in accordance with one embodiment of the present disclosure. to be.

The system according to an embodiment of the present disclosure may include a plurality of wireless power base stations. For example, referring to FIG. 1, the system may include a first base station 100 and a second base station 300. The first and second base stations 300 may transmit power energy to the wireless communication terminals 200a, 200b, and 200c through a wireless communication scheme. In this case, the first and second base stations 100 are wireless communication terminals 200a and 200b through Bluetooth, WIFI, ZigBee, visible light communication, and other data communication methods such as 3G and LTE. , 200c) may perform wireless communication, but the wireless communication method is not limited thereto.

According to one embodiment, the at least one base station may additionally be equipped with a data communication function. For example, the first base station 100 may be a hybrid access point (H-AP) having a wireless data communication function and a wireless power supply function. Specifically, the first base station 100 may perform data communication with the wireless communication terminals 200a, 200b, and 200c to be described later in addition to power supply using a wireless communication method. The first base station 100 and the wireless communication terminals 200a, 200b, and 200c may transmit and receive wireless signals through a predetermined frequency band. The first base station 100 may transmit a radio signal to the wireless communication terminals 200a, 200b, and 200c included in the coverage 101.

According to an embodiment, the second base station 300 may supply wireless power energy to the wireless communication terminals 200a and 200b. For example, unlike the first base station 100, the second base station 300 may be a base station that supplies only wireless power to the wireless communication terminals 200a and 200b, but is not limited thereto. The wireless communication terminals 200a and 200b may convert all of the wireless signals received from the second base station 300 into power energy. In this case, the second base station 300 may be a non-coupling device decoupled with the first base station 100.

For example, the second base station 100 may transmit a radio signal to the wireless communication terminals 200a and 200b included in the coverage 301. In this case, the second base station 300 may transmit a radio signal to the wireless communication terminals 200a and 200b through a channel independent of the first base station 100.

According to an embodiment, the second base station 300 may be installed within a preset range based on the location where the first base station is installed. For example, the second base station 300 may be installed within the coverage 101 of the first base station 100. Alternatively, the second base station 300 may be installed in a preset area including the coverage 101 of the first base station 100.

According to one embodiment, when the second base station 300 transmits only wireless power, the second base station 300 is a power beacon (PB) used to increase the coverage of wireless power charging in the system. Can be.

According to one embodiment, when the system additionally includes a second base station 300 which is a non-coupling device uncoupled with the first base station 100, the second wireless communication terminal 200 may be configured as a second base station ( 300 may be powered from. On the contrary, in a system not including the second base station 300, the second wireless communication terminal 200b may not receive sufficient power from the first base station 100 compared to the first wireless communication terminal 200a. . The system can provide a stable wireless power charging environment to a plurality of terminals in the system by extending the coverage for supplying wireless power through the second base station 300.

In addition, when the system includes the second base station 300, it is possible to improve the data communication environment between the first base station and the wireless communication terminal 200. For example, the first base station 100 may secure power for data communication based on the power provided to the wireless communication terminal from the second base station 300.

A decoupled RF energy harvesting system for an energy harvesting network system including a separate power transfer base station independent of the first base station 100, such as the second base station 300, shown in FIG. 1. network, DRF-EHN).

According to an embodiment, the wireless communication terminals 200a, 200b, and 200c may receive power through a wireless signal from a plurality of base stations. In addition, the wireless communication terminals 200a, 200b, and 200c may perform wireless communication with the base station. The wireless communication terminals 200a, 200b, and 200c may be a mobile computing device such as a smartphone, a tablet PC, a mobile phone, a laptop, a wearable device such as a watch having a communication function and a wireless power charging function. However, the present invention is not limited thereto, and the wireless communication terminals 200a, 200b, and 200c may include all kinds of mobile devices capable of communicating data and charging power through a wireless signal with the base station.

In FIG. 1, the processor managing the system is not illustrated, but the first base station performs the operation of managing the entire system, but the present invention is not limited thereto. For example, the system may include a separate processor for optimizing the performance of the energy harvesting network. The system may include a separate processor for determining communication parameters and transmitting the determined communication parameters to the first base station 100 and the second base station 300. In addition, a separate processor may perform operations of the first base station 100 described throughout the present disclosure.

According to an embodiment, when the wireless communication terminal 200 receives power from a plurality of base stations, a problem may occur in which energy efficiency is lowered due to an interference problem. For example, when the wireless communication terminal 200 receives power from the first base station 100 and the second base station 300, the coverage of the first base station 100 and the second base station 300. The 301 may overlap and the energy efficiency may be reduced.

The first base station 100 according to an embodiment of the present disclosure is generated by allocating time division intervals for wireless signal transmission to each of the first base station 100 and the second base station 300 included in the system. The reduction in energy efficiency can be reduced. For example, the first base station 100 may allocate a transmission time for each base station in a time division manner so that one base station transmits a radio signal in one divided time division period.

Hereinafter, a method of allocating a time division interval, which is a time for transmitting a radio signal by each of the first base station 100 and the second base station 300, according to an exemplary embodiment will be described with reference to FIG. 2. It demonstrates with reference.

2 is a diagram illustrating the configuration of the first base station 100 and the second base station 300 according to an embodiment of the present disclosure. Referring to FIG. 2, the system includes a first base station 100 that is a hybrid access point (H-AP), a second base station 300 that is a power beacon (PB), or an uncoupled device, and a plurality of wireless communication terminals 200. ) May be included.

According to an embodiment, the first base station 100 may include a first communication unit 110 and a processor 120. However, not all of the components shown in FIG. 2 are essential components of the first base station 100. The first base station 100 may be implemented by more components than those illustrated in FIG. 2, and the first base station 100 may be implemented by fewer components than the components illustrated in FIG. 2.

The processor 120 may include one or more processors to control the overall operation of the first base station 100. For example, the processor 120 may control the first communication unit 110 by executing at least one program. In addition, the processor 120 may execute at least one program to perform a function of the first base station 100 described with reference to FIGS. 4 to 5. For example, the processor 120 may transmit a radio signal to the wireless communication terminal 200 through the first communication unit 110 by executing at least one program.

According to an embodiment, the processor 120 may allocate a time division interval for transmitting a radio signal to each of the first base station 100 and the second base station 300. For example, the first time division period may be a time division period in which any one of the first base station 100 and the second base station 300 may transmit a radio signal to the wireless communication terminal 200. The second time division period may be a time division period in which the other one of the first base station 100 and the second base station 300 transmits a radio signal to the wireless communication terminal 200.

In detail, the processor 120 may transmit a wireless signal to the wireless communication terminal 200 during the first time division period through the first communication unit 110 to be described later. The second base station 300 may transmit a radio signal to the wireless communication terminal 200 during the second time division period through the second communication unit 310 to be described later.

The first communication unit 110 can include one or more components that allow the first base station 100 to communicate with the wireless communication terminal 200 and other base stations in the network. Another base station may include a second base station 300. The first communication unit 110 may include at least one antenna for transmitting and transmitting a radio signal to the plurality of wireless communication terminals 200.

According to an embodiment, the first communication unit 110 may transmit a radio signal based on the time division scheme determined by the processor 120. The first communication unit 110 may transmit time division information determined by the processor 120 to the second base station 300 and the wireless communication terminal 200.

In this case, the first communication unit 110 may include a mobile communication unit and a short range communication unit. The mobile communication unit may connect to a mobile communication network according to various standards such as LTE, WiMAX, and Wibro. The short range communication unit may include a Bluetooth communication unit, a BLE (Bluetooth Low Energy) communication unit, a near field communication unit (Near Field Communication unit), WLAN (Wi-Fi) communication unit and the like, but is not limited thereto.

According to an embodiment, the second base station 300 may include a second communication unit 310. However, not all of the components shown in FIG. 2 are essential components of the second base station 300. The second base station 300 may be implemented by more components than those illustrated in FIG. 2, and the second base station 300 may be implemented by fewer components than those illustrated in FIG. 2.

According to an embodiment, the second communication unit 310 may receive a communication parameter for transmitting a radio signal from the first base station 100. In addition, the second communication unit 310 may transmit a radio signal based on the received communication parameter. For example, the second communication unit 310 may transmit a wireless signal to the wireless communication terminal 200 during a time division period in which the second base station 300 is allocated to transmit the wireless signal. In this case, the wireless signal transmitted by the second base station 300 may be for supplying power to the wireless communication terminal 200.

In this case, the second communication unit 310 may include a mobile communication unit and a short range communication unit. The mobile communication unit may connect to a mobile communication network according to various standards such as LTE, WiMAX, and Wibro. The short range communication unit may include a Bluetooth communication unit, a BLE (Bluetooth Low Energy) communication unit, a near field communication unit (Near Field Communication unit), WLAN (Wi-Fi) communication unit and the like, but is not limited thereto. In addition, the second communication unit 310 may include at least one antenna for transmitting a radio signal to the plurality of wireless communication terminals 200.

According to an embodiment, the first communication unit 110 and the second communication unit 310 may transmit a radio signal through different channels. For example, the channel characteristics between the first base station and the wireless communication terminal and the channel characteristics between the second base station and the wireless communication terminal may change independently of each other.

Meanwhile, according to an exemplary embodiment, the first base station 100 may allocate a time division interval for each of the first base station 100 and the second base station 300 in consideration of network environment information. This is because, when a plurality of base stations simultaneously supply power to wireless communication terminals through different channels, time division sections may be allocated differently in order to optimize energy efficiency according to a network environment.

In addition, when data transmission and power supply are simultaneously performed through a wireless signal, a time division interval allocated for optimizing energy efficiency may be considered together with a power energy ratio that is energy harvested in the wireless communication terminal. Increasing the data communication rate by determining the rate at which the power received from the H-AP (eg, the first base station) is divided by taking into account the power received from the uncoupled device (eg, the second base station). Because it can.

Hereinafter, a method in which the first base station 100 transmits a wireless signal using a communication parameter determined based on network environment information will be described with reference to FIG. 3.

3 is a flowchart illustrating a method of operating the first base station 100 as a hybrid access point according to an embodiment of the present disclosure.

Referring to FIG. 3, in step S302, the first base station 100 may determine a communication parameter based on network environment information. Here, the network environment information may include the maximum transmittable amount of transmittable power of the first base station 100, the maximum transmittable amount of transmittable power of the second base station 300, and guaranteed quality of service criteria. In this case, the first base station 100 may receive information on the maximum amount of transmit power that the second base station 300 can transmit from the second base station 300.

In addition, the network environment information is a quality of service (QoS) related to the data rate (bit per second (bps)) and the quality of service that is guaranteed for each of the plurality of wireless communication terminals 200 in the system is supplied AoP (amount of harvested power) information associated with the amount of power may be included. For example, the network environment information may include information about a probability that a preset data transmission rate is guaranteed for each wireless communication terminal 200. The network environment information may include information about a probability that a preset minimum amount of power is guaranteed for each wireless communication terminal 200.

In addition, the network environment information may include information related to the channel model. The channel model may be determined based on the physical environmental elements of the network. For example, the physical environmental elements of the network may include structural features on which reflected waves are formed. The channel model may include rayleigh fading and rician fading channel models. The first base station 100 may receive channel information between the second base station and the wireless communication terminal 200 from the second base station 300 to obtain network environment information.

For example, the first base station 100 may determine communication parameters by substituting network environment information into an operation for optimizing energy efficiency. In this case, the energy efficiency may be determined according to the power consumption compared to the channel capacity of the entire system.

Here, the channel capacity is the ratio of the time division interval allocated to the first base station 100 among the entire time intervals, the ratio of the power allocated to data transmission among the total power received by the wireless communication terminal 200 and the first base station. 100 may be determined according to the amount of power transmitted to the wireless communication terminal 200. In addition, the power consumption may be determined by the difference between the amount of energy harvested in the wireless communication terminal 200 in the total power transmission amount transmitted from the plurality of base stations (100, 300). In detail, the first base station 100 may use a Lagrangian dual decomposition method to determine a communication parameter for optimizing energy efficiency. The operation of optimizing the energy efficiency of the system will be described in detail with reference to FIG. 5 to be described later.

Here, the communication parameter may include a ratio between time division intervals allocated to each of the first base station 100 and the second base station 300. Here, the ratio between the time division sections may represent a ratio of the time division sections allocated to the first base station 100 to the time division sections allocated to the second base station 300 in the entire time section.

 For example, the first base station 100 may determine a ratio of time division intervals allocated to each of the first base station 100 and the second base station 300 based on the network environment information. For example, the first base station 100 determines a ratio of time division intervals allocated to the first base station 100 in the entire time interval as 'x', and the second base station 300 in the entire time interval. A ratio of time division intervals to be allocated may be determined as '1-x'. In this case, 'x' may be a value larger than '0' and smaller than '1'.

In addition, the communication parameter may include a power ratio indicating a ratio of the amount of power converted to the power energy of the wireless communication terminal to the amount of power allocated to receive data from the total power of the wireless signal transmitted from the first base station 100. Can be.

The first base station 100 according to the exemplary embodiment of the present disclosure may simultaneously determine the ratio between the time division intervals and the power ratio based on the network environment. The first base station 100 may increase energy efficiency while guaranteeing preset data rates for the plurality of wireless communication terminals 200 through the above-described operation.

In addition, the communication parameter is a first power amount indicating the power size of the radio signal transmitted by the first base station 100 to the wireless communication terminal 200 and the second base station 300 is transmitted to the wireless communication terminal 200 It may include a second amount of power indicating the amount of power of the wireless signal.

Meanwhile, according to an embodiment, the first base station 100 may update communication parameters for optimizing energy efficiency at predetermined intervals. Here, the predetermined period may be determined according to the system environment. For example, in an environment in which the number or type of wireless communication terminals included in the system is rapidly changed (for example, an environment with a large floating population), the predetermined period may be shortened. This is because the network environment can be changed quickly due to the newly added wireless communication terminal.

In operation S304, the first base station 100 may allocate a time division interval to each of the first base station 100 and the second base station 300. For example, the first base station 100 may allocate a time division interval to the first base station 100 and the second base station 300 based on the communication parameter. The time division interval allocated to the first base station 100 may indicate a time for the first base station 100 to transmit a radio signal. In addition, the time division interval allocated to the second base station 300 may indicate a time when the second base station 300 transmits a radio signal.

According to one embodiment, the first base station 100 is based on the ratio between the time division intervals allocated to each of the first base station 100 and the second base station 300, the first base station 100 and A time division interval may be allocated to the second base station 300. For example, when the ratio of the time division interval allocated to the second base station 300 is greater in the entire time interval, the first base station 100 may have a larger number of time division intervals for the second base station 300. Can be assigned.

Alternatively, the first base station 100 may be configured based on the ratio of the time division interval, the power ratio, and the amount of power of radio signals transmitted by each of the first base station and the second base station 300. A time division section may be allocated to the second base station 300. The first base station 100 transmits a wireless signal in consideration of the time division ratio, the power ratio, the first power amount, and the second power amount simultaneously, thereby presetting data rates and preset minimum values for the plurality of wireless communication terminals 200. Energy efficiency can be increased while ensuring power supply.

In operation S306, the first base station 100 may transmit a wireless signal to the wireless communication terminal 200 based on a communication parameter during the time division period allocated to the first base station 100. For example, the first base station 100 may transmit a radio signal to the wireless communication terminal 200 during the time division period allocated in step S304. In this case, the first base station 100 may transmit a radio signal based on the communication parameter determined in step S302.

For example, the first base station 100 may transmit a radio signal with a first amount of power. The first base station 100 may transmit a radio signal to the wireless communication terminal 200 with a first amount of power during the allocated time division period.

At this time, the wireless communication terminal 200 receiving the wireless signal may perform an operation of data decoding a portion of the wireless signal received from the first base station according to a preset ratio and converting the portion to power energy. Here, the preset ratio is a power ratio indicating a ratio of the amount of power converted into the power energy of the wireless communication terminal to the amount of power allocated to receive data from the total power of the radio signal transmitted from the first base station 100. Can be represented.

Meanwhile, according to an embodiment, the first base station 100 may transmit the determined communication parameters to the wireless communication terminal 200 and the second base station 300, respectively. For example, the first base station 100 may transmit power ratio information determined based on the network environment information to the wireless communication terminal 200.

In addition, the first base station 100 may transmit the second power amount information determined based on the network environment information to the second base station 200. In this case, the second base station 300 may transmit the wireless signal of the second power amount to the wireless communication terminal 200 based on the received second power amount information.

According to an embodiment, the first base station 100 may transmit the allocated time division interval information to the wireless communication terminal 200 and the second base station 300, respectively. The wireless communication terminal 200 may receive a radio signal from a plurality of base stations based on the received time division information. In addition, the second base station 300 may transmit a wireless signal that is a second amount of power during the time division period allocated to the second base station 300 to the wireless communication terminal 200.

As described above, the wireless communication terminal 200 according to an embodiment of the present disclosure may receive data through a part of the radio signal and perform energy harvesting through the remaining part. In this case, the wireless communication terminal 200 may use the power ratio determined by the first base station 100 to optimize the energy efficiency of the energy harvesting network system. When the ratio of the radio signal converted into power energy is higher than the ratio of the radio signal allocated for data communication, the transmission rate of the data communication provided by the radio communication terminal 200 may drop, and vice versa, the radio communication terminal ( This may be due to the lack of power energy that can be supplied by 200).

Hereinafter, the configuration of the wireless communication terminal 200 according to an embodiment of the present disclosure will be described with reference to FIGS. 4A and 4B.

4A is a block diagram illustrating a wireless communication terminal 200 according to an embodiment of the present disclosure.

According to FIG. 4, the wireless communication terminal 200 according to the embodiment of the present invention may include a communication unit 210 and a processor 230. However, not all of the components shown in FIG. 4 are essential components of the wireless communication terminal 200. The wireless communication terminal 200 may be implemented by more components than those illustrated in FIG. 4, and the wireless communication terminal 200 may be implemented by fewer components than those illustrated in FIG. 4.

The communication unit 210 may include one or more components that allow the wireless communication terminal 200 to communicate with the first base station 100 and the second base station 300 in a network. The communication unit 210 may include at least one antenna for receiving a radio signal from a plurality of base stations.

According to an embodiment, the communication unit 210 may receive a radio signal from the first base station 100 and the second base station 300. The communication unit 210 may receive information necessary for processing the radio signal in the processor 220. For example, the communication unit 210 may receive communication parameters and time division interval information allocated to the first base station 100 and the second base station 300 from the first base station 100.

In this case, the communication unit 210 may include a mobile communication unit and a short range communication unit. The mobile communication unit may connect to a mobile communication network according to various standards such as LTE, WiMAX, and Wibro. The short range communication unit may include a Bluetooth communication unit, a BLE (Bluetooth Low Energy) communication unit, a near field communication unit (Near Field Communication unit), WLAN (Wi-Fi) communication unit and the like, but is not limited thereto.

The processor 220 may include one or more processors to control the overall operation of the wireless communication terminal 200. For example, the processor 220 may control the communication unit 210 by executing at least one program. In addition, the processor 220 may perform the function of the wireless communication terminal 200 described with reference to FIGS. 1 to 3 by executing at least one program. Hereinafter, the operation of the processor 220 will be described in detail with reference to FIG. 4B.

4B is a block diagram illustrating a power flow of a wireless signal received at a wireless communication terminal 200 according to an embodiment of the present disclosure.

As shown in FIG. 4B, the processor 220 may distribute the power of the wireless signal received through the communication unit 210 to the power allocated for data demodulation and the power for energy conversion. The processor 220 may distribute the power of the wireless signal to the power allocated for data reception and the power for energy harvesting based on the communication parameters. Here, the distribution may mean that the power allocated for data and the power for harvesting energy are distinguished and transmitted to the corresponding circuit in the wireless communication terminal 200. According to an embodiment, the wireless communication terminal 200 may distribute the power of the received wireless signal according to a preset power ratio. For example, the wireless communication terminal 200 can include a power splitting antenna.

For example, the processor 220 may convert the amount of power that is converted into power energy stored in the wireless communication terminal 200 to the amount of power allocated to receive data from the total power of the wireless signal received from the first base station 100. Based on the power ratio information indicating the ratio (1-θ: θ), the wireless signal received through the communication unit 210 may be converted into power energy.

In detail, the processor 220 may use the amount of power corresponding to 'θ' in the total power of the wireless signal received from the first base station 100 through the communication unit 210 as the power energy stored in the wireless communication terminal 200. I can convert it. The wireless communication terminal 200 may include a rectenna for power energy conversion. Here, the rectenna is a compound word of a rectifier and an antenna, and the received radio wave may be converted into power energy through a rectifier circuit.

According to an embodiment, the processor 220 may receive power ratio information from the first base station 100 through the communication unit 210. For example, the processor 220 may acquire a communication parameter in an association step of initiating a connection between the first base station 100 and the wireless communication terminal 200 through the communication unit 210.

Hereinafter, an example in which the first base station 100 determines a communication parameter for optimizing energy efficiency of the system will be described in detail with reference to FIG. 5.

5 is a flowchart illustrating operation of the first base station 100 to determine communication parameters to optimize energy efficiency according to one embodiment of the present disclosure.

In operation S502, the first base station 100 may define energy efficiency. Energy efficiency defined in accordance with one embodiment of the present disclosure can be expressed by Equation 1.

As shown in Equation 1, the first base station 100 may define the energy efficiency η using the channel capacity C and the power consumption P. In Equation 1, k may be an identifier for identifying each wireless communication terminal 200. For example, when a total of six wireless communication terminals 200 are included in the system, k may be any number between '1' and '6'. The first base station 100 may determine different communication parameters for each wireless communication terminal 200. In addition, the first base station 100 may transmit a radio signal based on different communication parameters.

)에 기초하여 결정될 수 있다.In Equation 1, the channel capacity C is a time division interval ratio μ allocated to the first base station 100, and a ratio of power allocated to data transmission among total power received by the wireless communication terminal 200 (1). -θ) and the amount of power transmitted by the first base station 100 to the wireless communication terminal 200 (

Can be determined based on

),제2 베이스 스테이션(300)이 무선 통신 단말(200)로 전송하는 전력량(

),제1 베이스 스테이션(100)에게 할당된 시분할 구간 비율(μ) 및 제1 베이스 스테이션(100)에게 할당된 시분할 구간 비율(1-μ)에 기초하여 결정될 수 있다. 또한, 제1 베이스 스테이션(100)은

및

외에, 추가적으로 각각의 베이스 스테이션의 전력 송출 효율 및 회로에서 소진되는 전력 에너지에 기초하여 전체 전력 송출량을 계산할 수 있다. 또한, 무선 통신 단말(200)에서 에너지 하베스팅되는 전력량은 무선 통신 단말(200)에게 수신되는 전체 전력 중에서 전력 에너지로 변환되는 전력의 비율(θ)에 기초하여 결정될 수 있다.In Equation 1, the power consumption amount P may be determined as a difference between the amount of energy harvested in the wireless communication terminal 200 in the total amount of power output from the plurality of base stations 100 and 300. The total power transmission amount is the amount of power transmitted by the first base station 100 to the wireless communication terminal 200 (

), The amount of power transmitted by the second base station 300 to the wireless communication terminal 200 (

) May be determined based on the time division interval ratio μ allocated to the first base station 100 and the time division interval ratio 1-μ assigned to the first base station 100. In addition, the first base station 100

And

In addition, the total power output may be calculated based on the power delivery efficiency of each base station and the power energy consumed in the circuit. In addition, the amount of energy harvested in the wireless communication terminal 200 may be determined based on a ratio θ of power converted into power energy among the total power received by the wireless communication terminal 200.

In operation S504, the first base station 100 may convert the energy efficiency defined in order to optimize the energy efficiency into an energy efficiency function in the form of convex. For example, the first base station 100 may convert the energy efficiency defined in step S502 using Equation 2 using a nonlinear fractional programming method. Η in Equation 2 may be any constant updated through steps S508 to S512 to be described later.

In operation S506, the first base station 100 may determine a communication parameter for optimizing energy efficiency using the optimization parameter.

For example, in the first step, the first base station 100 may determine a communication parameter by using an initial value of a preset optimization parameter. In detail, the first base station 100 may determine a communication parameter by using a Lagrange dual decomposition method, but is not limited thereto, and another optimization method may be used.

According to an embodiment, when the first base station 100 uses the Lagrangian dual decomposition method, the number of optimization parameters that are lagrange multipliers may be equal to the number of network environment information types. For example, the first base station 100 may determine the communication parameter by substituting the network environment information described in FIG. 3. In detail, the optimization parameter may include first and second optimization parameters mapped to the maximum transmittable amount of transmit power of the first base station 100 and the maximum transmittable amount of transmit power of the second base station 300 described in FIG. 3. It may include. Alternatively, the optimization parameter may include information about a probability that a preset data rate is guaranteed for the wireless communication terminal 200 described in FIG. 3 and a probability that a predetermined minimum amount of power is guaranteed for the wireless communication terminal 200. It may further include third and fourth optimization parameters mapped to each piece of information about.

In addition, the first base station 100 may determine the communication parameter by updating the optimization parameter based on the gradient methods. In addition, the first base station 100 may determine a communication parameter using a KKT condition (Karush-Kuhn tucker). The KKT condition may refer to a condition where a value obtained by differentiating an optimization function according to the Lagrangian dual decomposition method into each optimization parameter becomes '0'. The first base station 100 may determine a communication parameter by combining equations according to KKT conditions.

In step S508, the first base station 100 may determine whether the energy efficiency function defined in step S504 converges based on the determined communication parameter. For example, the first base station 100 may determine whether to converge the energy efficiency function by comparing with a preset value. In this case, the preset value may be a value approximating a predefined zero.

In operation S510, when the energy efficiency function does not converge, in operation S512, the first base station 100 may update the optimization parameter. The first base station 100 may update the optimization parameter used in step S506. In addition, the first base station 100 may update 'η' of Equation 2 in step S504. In addition, the first base station 100 may repeat steps S506 to S512 until the energy efficiency function determined in step S508 converges.

In operation S510, when the energy efficiency function converges, the first base station 100 may determine the communication parameter determined in operation S506 as a communication parameter for optimizing energy efficiency.

In operation S514, the first base station 100 may transmit a wireless signal using the communication parameter determined in operation S506. In addition, the first base station 100 may transmit the communication parameters determined in step S506 to the wireless communication terminal 200 and the second base station 300.

In addition, the first base station 100 may allocate a time division interval to the first base station 100 and the second base station 300 based on the communication parameter determined in operation S506. In addition, the first base station 100 may transmit the allocated time division intervals to the wireless communication terminal 200 and the second base station 300.

Some embodiments may also be embodied in the form of a recording medium containing instructions executable by a computer, such as program modules executed by the computer. Computer readable media can be any available media that can be accessed by a computer and can include both volatile and nonvolatile media, removable and non-removable media. In addition, the computer readable medium may include a computer storage medium. Computer storage media may include both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

Further, in this specification, “unit” may be a hardware component such as a processor or circuit, and / or a software component executed by a hardware component such as a processor.

The foregoing description of the disclosure is provided by way of example, and it will be understood by those skilled in the art that the present disclosure may be easily modified into other specific forms without changing the technical spirit or essential features of the present disclosure. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present disclosure is indicated by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present disclosure. do.

Claims (12)

In the wireless energy harvesting network system comprising a plurality of base stations and a plurality of wireless communication terminals,
A first base station for performing data communication and power transmission via a wireless signal;
A second base station performing power supply via a wireless signal; And
A wireless communication terminal for receiving a radio signal from each of the first base station and the second base station, and converting the received radio signal into power energy based on communication parameter information;
The first base station and the second base station transmits a radio signal to the wireless communication terminal through a different channel during each time division period allocated to each in a time division manner,
The respective time division intervals are allocated based on the communication parameter information,
The communication parameter information is determined based on network environment information, and represents a parameter for optimizing energy efficiency determined according to power consumption compared to channel capacity of the entire system.
The network environment information is based on a probability that a maximum transmit power amount of the first base station, a maximum transmit power amount of the second base station, and a preset data rate for each wireless communication terminal are guaranteed. And information about a probability that a predetermined minimum amount of power is guaranteed for each wireless communication terminal. A base station for performing data communication and power transmission through a wireless signal in an energy harvesting network system,
Communication unit for transmitting and receiving a wireless signal; And
Includes a processor,
The processor executes at least one program,
Information on the maximum transmittable amount of transmit power of the base station, the maximum transmittable amount of transmit power of the uncoupled device for wireless power transmission, and the probability that a preset data rate is guaranteed for each wireless communication terminal; Determining a communication parameter for optimizing energy efficiency determined according to power consumption to channel capacity of the entire system based on network environment information including information about a probability that a predetermined minimum amount of power is guaranteed for a wireless communication terminal of
Allocate a time division interval for each wireless signal transmission to each of the base station and the uncoupled device based on the determined communication parameter,
Transmitting a radio signal to the wireless communication terminal based on the determined communication parameter during the time division period assigned to the base station,
And the non-coupling device is a device for transmitting a radio signal for power transmission on a channel independent of the base station to the wireless communication terminal.
delete The method of claim 2,
Communication parameters for optimizing the energy efficiency,
Equation for maximizing the energy efficiency η

Is determined using
The channel capacity (C) is the ratio (μ) between the time division intervals allocated to each of the base station and the uncoupled device, and the power allocated for data transmission among the total power received from the base station to the wireless communication terminal. Ratio (1-θ) and the amount of power transmitted by the base station to the wireless communication terminal (

),
The power consumption amount P is a ratio (μ) between the time division intervals, a ratio (θ) of power amount converted into power energy of the wireless communication terminal among the total power received from the base station to the wireless communication terminal, and the base. Amount of power transmitted by the station to the wireless communication terminal

And the amount of power transmitted by the uncoupled device to the wireless communication terminal (

),
K is a base station that identifies a plurality of wireless communication terminals including the wireless communication terminal. The method of claim 2,
The processor,
Based on the network environment information, determine a ratio between time division intervals allocated to each of the base station and the non-coupling device,
Based on the ratio, determine a first time division section that is a time division section in which the base station transmits a radio signal and a second time division section that is a time division section in which the non-combining device transmits a radio signal,
The base station transmits a radio signal to the wireless communication terminal during the first time division section and transmits information on the second time division section to the non-coupling device through the communication unit.
The method of claim 2,
The processor,
A first power amount indicating a power amount of a radio signal transmitted from the base station to the wireless communication terminal based on the network environment information, and a second power amount indicating a power amount of a radio signal transmitted from the non-coupling device to the wireless communication terminal; Determine the power,
Transmits a wireless signal with the first amount of power through the communication unit;
And transmit power amount information indicating the second power amount to the uncoupled device. The method of claim 2,
The processor,
Determining a power ratio indicating a ratio of the amount of power converted into power energy of the wireless communication terminal to the amount of power allocated to receive data among the total power of the wireless signal transmitted from the base station based on the network environment information, and Transmits information indicating a power ratio to the wireless communication terminal,
The power ratio is used to convert a wireless signal received at the wireless communication terminal into power energy. The method of claim 2,
And the processor updates communication parameters for optimizing the energy efficiency every predetermined period. A wireless communication terminal for obtaining power energy and data from a wireless signal transmitted by a plurality of base stations,
A communication unit for transmitting and receiving wireless signals from the plurality of base stations; And
Includes a processor,
The processor executes at least one program,
Receiving information and a communication parameter for a time interval in which the radio signals allocated for each of the plurality of base stations are transmitted through the communication unit, and based on the information for the time interval in which the radio signal is transmitted, the plurality of bases Receives a radio signal transmitted through a different channel from each station, and converts the radio signal received through the communication unit into power energy based on the communication parameters,
The communication parameter information is determined based on network environment information, and represents a parameter for optimizing energy efficiency determined according to power consumption compared to channel capacity of the entire system.
The network environment information includes information about a maximum transmittable amount of transmit power of each of the plurality of base stations, information about a probability that a preset data rate is guaranteed for each wireless communication terminal, and information about each wireless communication terminal. And information about a probability that the set minimum amount of power is guaranteed.
The method of claim 9,
The communication parameter includes power ratio information indicating a ratio of power amount converted into power energy stored in the wireless communication terminal to the amount of power allocated to receive data in the total power of the wireless signals received from the plurality of base stations. ,
The processor,
And converting a radio signal received through the communication unit into power energy based on the power ratio information. In the method for the base station included in the energy harvesting network system to perform data communication and power supply via a wireless signal,
Information on the maximum transmittable amount of transmit power of the base station, the maximum transmittable amount of transmit power of the uncoupled device for wireless power transmission, and the probability that a preset data rate is guaranteed for each wireless communication terminal; Determining a communication parameter for optimizing energy efficiency determined according to power consumption to channel capacity of the entire system based on network environment information including information about a probability that a preset minimum amount of power is guaranteed for the wireless communication terminal of the system. ;
Allocating a time division interval for each wireless signal transmission to each of the base station and the non-coupling device based on the determined communication parameter; And
Transmitting a radio signal based on the determined communication parameter to a wireless communication terminal during a time division interval allocated to the base station,
And the non-coupling device is a device for transmitting a wireless signal for power transmission on a channel independent of the base station to the wireless communication terminal. A computer-readable recording medium having recorded thereon a program for executing the method of claim 11 on a computer.

Images