Energy relay green wireless charging system and energy relay matching method thereof

Abstract

The present invention relates to an energy relay green wireless charging system and an energy relay matching method. In the charging system, a green energy far-field wireless charging base station is located in the center of a region, capable of collecting green energy and regularly performing far-field wireless charging for a wireless sensor network in the form of electromagnetic radiation. The wireless charging system provided by the present invention not only ensures the normal operation of the sensor network, but also reduces the damage to the environment caused by charging consumption. In addition, the present invention also provides an energy relay matching method for the system, which consists of three steps: sub-region division, energy relay balancing, and energy relay allocation. It can achieve a multi-to-one matching of energy relays and sensor nodes with less energy with lower time complexity on the basis of wireless charging using an energy relay scheme, thereby reducing energy loss during retransmission, increasing utilization, and reducing the mortality rate of nodes in the entire sensor network.

Description

Technical Field

[0001] The present invention relates to the field of communication and energy technology, and in particular to an energy relay green wireless charging system and an energy relay matching method thereof. Background Art

[0002] Wireless sensors inherit the basic functions of conventional sensors and are unaffected by power lines, making them easier to deploy and manage. This makes them suitable for widespread use in a variety of scenarios, including smart homes, smart factories, and smart farms. According to the article "Power Challenges Caused by IoT Edge Nodes: Securing and Sensing Our World," the number of wireless sensors in use is projected to reach 45 trillion by 2032, leading to massive energy demands and serious challenges in powering sensor networks. Relying solely on traditional fossil fuels for these charging needs would cause significant environmental damage and be inconsistent with sustainable development strategies. On the other hand, appropriate and efficient sensor network power supply methods would promote the rapid development and application of sensor networks, further improving energy efficiency and reducing waste. Currently, solutions for powering sensor networks fall into three main categories: node energy conservation, energy harvesting, and wireless charging.

[0003] Node energy-saving methods usually use some technologies to reduce the power consumption of wireless sensors on the network, such as shortening the working cycle, reducing data-driven methods and data mobility. These energy-saving methods generally reduce the consumption of sensor nodes per unit time by reducing certain network performance. The energy harvesting method refers to the node having its own self-powered microsystem, which collects energy from the environment and converts it into the energy required by itself through the microsystem to extend the network life cycle. In practical applications, despite this, high energy conversion rates cannot be guaranteed, and due to the instability of the environment, the energy acquisition process cannot be accurately predicted. The network of the wireless charging method (Wireless Power Transfer, WPT) needs to be equipped with fixed charging stations, or mobile charging devices and service station nodes to provide efficient charging services for sensor nodes. The entire power replenishment process can be predicted and controlled in advance.

[0004] WPT technologies primarily include electromagnetic induction charging, electromagnetic resonance charging, and electromagnetic radiation charging. Electromagnetic induction and electromagnetic resonance charging methods, due to their relatively short transmission distances, cannot be directly applied to charging in sensor networks. Consequently, many studies have used mobile carts or drones carrying chargers to charge near wireless sensors. This design is susceptible to interference from terrain and obstacles, and the charger consumes significant energy during node movement, reducing energy efficiency. Currently, many studies have focused on single-charger overlay charging to address base station coverage and scheduling, achieving promising results. However, the problem of insufficient energy and proneness to failure at edge nodes in overlay charging remains unresolved, limiting the application and development of overlay charging. Multi-hop resonant charging is an innovative approach to addressing the energy shortage at edge nodes. This method utilizes multiple electromagnetic coils and electromagnetic resonance charging for multiple energy transfers. This approach extends the charging range somewhat, allowing distant sensor nodes to receive energy. However, the use of multiple coils increases the size and cost of the charging equipment, while the increase in charging distance is minimal, hindering its practical application.

[0005] Existing wireless sensor network charging solutions do not choose to use green energy, which means that the power supply of wireless sensor networks will consume a huge amount of energy. If this energy is obtained by burning fossil fuels, it will cause great damage to the environment.

[0006] Furthermore, existing wireless sensor network charging solutions face a serious problem of insufficient power supply to edge nodes in the charging area, resulting in a high node mortality rate. While this node mortality issue can be addressed by extending the charging time of the base station, this approach reduces energy utilization and further increases energy consumption. Summary of the Invention

[0007] In view of the deficiencies in the prior art, the present invention aims to provide an energy relay green wireless charging system and an energy relay matching method thereof.

[0008] To achieve the above object, the present invention provides the following solutions:

[0009] An energy relay green wireless charging system comprises: a green energy far-field wireless charging base station and a plurality of sensor nodes; the sensor nodes are randomly distributed in a circular area with the green energy far-field wireless charging base station as the center;

[0010] The working cycle of the green energy far-field wireless charging base station includes a charging cycle and a green energy collection cycle that are cyclically cycled. The green energy far-field wireless charging base station is used to collect green energy during the charging cycle, convert the green energy into electrical energy, and charge the sensor node according to the electrical energy based on electromagnetic radiation. The green energy far-field wireless charging base station is also used to collect the green energy during the green energy collection cycle and stop supplying power to the sensor node.

[0011] The sensor node includes an energy relay node and an edge node; the energy relay node has both sensor functions and energy relay functions, that is, it is used for collecting, processing and returning environmental data, and storing the energy received from the green energy far-field wireless charging base station during the charging cycle, and sending the stored energy to the edge node during the green energy collection cycle; the edge node is used for collecting, processing and returning environmental data, and receiving and storing the energy transmitted by the green energy far-field wireless charging base station and the energy relay node.

[0012] Preferably, the green energy far-field wireless charging base station comprises: a green energy collection device, a battery and a base station antenna;

[0013] The green energy collection device is connected to the battery and the base station antenna respectively. The green energy collection device is used to collect the green energy and convert the green energy into direct current electricity; the battery is used to store the direct current electricity; the base station antenna is used to emit electromagnetic waves according to the direct current electricity to charge the sensor node.

[0014] Preferably, the green energy collection device includes a solar power generation device and a wind power generation device; the solar power generation device and the wind power generation device are both connected to the battery; and the green energy includes wind energy and solar energy.

[0015] Preferably, the energy relay node comprises: an energy receiving system, a receiving antenna, a switch module, a main battery, a secondary battery, a sensor, an energy transmitting system and a transmitting antenna;

[0016] The receiving antenna is connected to the energy receiving system, and the energy receiving system is connected to the main battery and the secondary battery respectively through the switch module; the main battery is connected to the sensor; the secondary battery is connected to the energy transmitting system, and the energy transmitting system is connected to the transmitting antenna;

[0017] The energy receiving system is used to receive the electric energy transmitted by the green energy far-field wireless charging base station through the receiving antenna, and charge the main battery through the switch module; the main battery is used to charge the sensor and support the sensor to collect, process and transmit data; the secondary battery is used to store the electric energy transmitted by the green energy far-field wireless charging base station, and send it to the edge node through the energy transmission system and the transmitting antenna.

[0018] Preferably, the distance between the energy relay node and the green energy far-field wireless charging base station is shorter than the distance between the edge node and the green energy far-field wireless charging base station.

[0019] Preferably, when the green energy far-field wireless charging base station charges all the sensor nodes within the charging cycle, the calculation formula for the charging power of the sensor nodes is:

[0020]

[0021] Among them, P t is the transmission power of the green energy far-field wireless charging base station, G0 is the transmitting antenna gain of the green energy far-field wireless charging base station, is the receiving antenna gain of the sensor node, η is the receiving circuit rectification efficiency of the sensor node, L p is the polarization loss between the transmitting antenna and the receiving antenna, The green energy far-field wireless charging base station is connected to the k-th sensor node v k distance, λ is the wavelength of electromagnetic waves used for energy transmission; P 0，vk is the charging power of the sensor node.

[0022] Preferably, when the green energy far-field wireless charging base station transmits energy to the edge node during the green energy collection period, the calculation formula for the charging power obtained by the edge node from the energy relay node is:

[0023]

[0024] in, and They are energy relay nodes v i The transmit power and transmit antenna gain, is the energy relay node v i and edge node v j The distance between them.

[0025] Preferably, the edge node v j From the energy relay node v iThe formula for calculating the maximum energy obtained is:

[0026]

[0027] in, is the energy relay node v i The amount of power received from the secondary battery.

[0028] An energy relay matching method for an energy relay green wireless charging system is applied to the above energy relay green wireless charging system. The energy relay matching method includes:

[0029] Any edge node in the circular area is taken as the first node, denoted as Among them, the ray from the center O to this edge node is expressed as The ray from the center O to other edge nodes is represented by Ov j ,ray With ray Ov j The angle between them is expressed as

[0030] according to All the edge nodes are sorted from small to large, and the edge nodes after sorting are represented as j=1,2,...,J;

[0031] Based on the sorting, each consecutive n edge nodes are divided into a group to obtain H edge node groups; each edge node group occupies a subregion, and the boundary between two adjacent subregions is a ray from the center of the circle to the midpoint of the two closest edge nodes in the two adjacent subregions;

[0032] Dividing the circular area into a plurality of sector-shaped sub-areas according to the boundary;

[0033] Determine the two adjacent fan-shaped sub-areas and Energy relay nodes and Quantity size, if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the Node replenish energy; is a floor function; if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the network replenish energy;

[0034] The edge nodes in the first sector sub-area are sorted from large to small according to the distance from the edge node to the green energy far-field wireless charging base station, and an energy relay node is assigned to the edge node according to the sorting. The formula of the energy relay node is expressed as: target =arg max(E(v h,i ,v h,1 )); where v h,i is the i-th energy relay node in the h-th sector sub-area, v h,1 is the first edge node in the h-th fan-shaped sub-region;

[0035] When all edge nodes in the first sector sub-area have obtained an energy relay, the next round of allocation is carried out;

[0036] When the allocated energy relay nodes meet the energy requirements of all edge nodes or all energy relays in this sector sub-area are allocated, the relay allocation of this sector sub-area is completed; the same energy relay allocation operation is performed in all sector sub-areas until the energy relay node allocation of the entire circular area is completed.

[0037] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0038] The present invention provides an energy relay green wireless charging system. In this charging system, a green energy far-field wireless charging base station is located in the center of the region. In a specific embodiment, it can use the assembled solar panels and wind power generation devices to collect green energy and use electromagnetic radiation to regularly perform far-field wireless charging for the wireless sensor network. The wireless charging system provided by the present invention not only ensures the normal operation of the sensor network, but also reduces the damage to the environment caused by charging consumption. In addition, the present invention also provides an energy relay matching method for the system, which consists of three steps: sub-region division, energy relay balancing, and energy relay allocation. It can achieve a one-to-one matching of energy relays with sensor nodes with less energy on the basis of wireless charging using an energy relay scheme with lower time complexity, thereby reducing energy loss during retransmission, increasing utilization, and reducing the mortality rate of nodes in the entire sensor network. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 This is an architecture diagram of the energy relay green wireless charging system in the embodiment provided by the present invention;

[0041] Figure 2 The working cycle of the green energy far-field wireless charging base station in the embodiment provided by the present invention;

[0042] Figure 3 The relay node structure in the embodiment provided by the present invention;

[0043] Figure 4 This is a method for dividing fan-shaped sub-regions in an embodiment provided by the present invention. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] The purpose of the present invention is to provide an energy relay green wireless charging system and its energy relay matching method, which can not only ensure the normal operation of the sensor network, but also reduce the damage to the environment caused by charging consumption, and make the energy loss during the retransmission process smaller, the utilization rate higher, and the mortality rate of the entire sensor network node lower.

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] Figure 1 This is a diagram of the energy relay green wireless charging system architecture in the embodiment of the present invention. Figure 1 As shown, an energy relay green wireless charging system in this embodiment includes: a green energy far-field wireless charging base station and a plurality of sensor nodes; the sensor nodes are randomly distributed in a circular area with the green energy far-field wireless charging base station as the center;

[0048] The working cycle of the green energy far-field wireless charging base station includes a charging cycle and a green energy collection cycle that are cyclically cycled. The green energy far-field wireless charging base station is used to collect green energy during the charging cycle, convert the green energy into electrical energy, and charge the sensor node according to the electrical energy based on electromagnetic radiation. The green energy far-field wireless charging base station is also used to collect the green energy during the green energy collection cycle and stop supplying power to the sensor node.

[0049] The sensor nodes include energy relay nodes (nodes within the area, Figure 1 ) and edge nodes ( Figure 1 The energy relay node has both sensor and energy relay functions, namely, it is used for collecting, processing and returning environmental data, and sending the stored energy to the edge node during the green energy collection cycle; the edge node is used for collecting, processing and returning environmental data, and receiving and storing the energy transmitted by the green energy far-field wireless charging base station and the energy relay node.

[0050] Specifically, the green wireless sensor network system based on energy relay is as follows Figure 1 As shown in the figure, K wireless sensor nodes are randomly distributed in a circular area with the green energy far-field wireless charging base station as the center. k Indicates that k=1,2,...,K.

[0051] The green energy far-field wireless charging base station is equipped with solar and wind power generation devices, which can convert green energy into direct current and store it in the base station's battery to support the operation of the base station. The green energy collection device can continuously collect green energy, but the converted direct current cannot enable the green energy far-field wireless charging base station to continuously transmit electromagnetic waves to charge the sensor nodes. The green energy far-field wireless charging base station can only switch between the charging cycle and the green energy collection cycle, which are represented by T and ΔT respectively. During the charging cycle, the green energy charging base station collects green energy and charges the sensors at the same time; during the green energy collection cycle, the base station only collects green energy and stops charging the sensor nodes. The working cycle of the green energy far-field wireless charging base station is as follows: Figure 2 shown.

[0052] Optionally, during the charging period T, the green energy far-field wireless charging base station charges all sensor nodes. Sensor nodes that are closer to the green energy far-field wireless charging base station can be directly fully charged by the green energy far-field wireless charging base station during this period, and will not consume light power in the next green energy collection period ΔT. These sensor nodes are called in-zone nodes and are represented by v iIndicates that i = 1, 2, ..., I, where I is the number of nodes in the area; nodes that are far away from the green energy far-field wireless charging base station may not be fully charged directly by the green energy far-field wireless charging base station, and consume light power in the following green energy collection period ΔT. These sensor nodes are called edge nodes and are represented by v j Denote j = 1, 2, ..., J, where J is the number of edge nodes.

[0053] Preferably, the green energy far-field wireless charging base station comprises: a green energy collection device, a battery and a base station antenna;

[0054] The green energy collection device is connected to the battery and the base station antenna respectively. The green energy collection device is used to collect the green energy and convert the green energy into direct current electricity; the battery is used to store the direct current electricity; the base station antenna is used to emit electromagnetic waves according to the direct current electricity to charge the sensor node.

[0055] Preferably, the green energy collection device includes a solar power generation device and a wind power generation device; the solar power generation device and the wind power generation device are both connected to the battery; and the green energy includes wind energy and solar energy.

[0056] Preferably, the energy relay node comprises: an energy receiving system, a receiving antenna, a switch module, a main battery, a secondary battery, a sensor, an energy transmitting system and a transmitting antenna;

[0057] The receiving antenna is connected to the energy receiving system, and the energy receiving system is connected to the main battery and the secondary battery respectively through the switch module; the main battery is connected to the sensor; the secondary battery is connected to the energy transmitting system, and the energy transmitting system is connected to the transmitting antenna;

[0058] The energy receiving system is used to receive the electric energy transmitted by the green energy far-field wireless charging base station through the receiving antenna, and charge the main battery through the switch module; the main battery is used to charge the sensor and support the sensor to collect, process and transmit data; the secondary battery is used to store the electric energy transmitted by the green energy far-field wireless charging base station, and send it to the edge node through the energy transmission system and the transmitting antenna.

[0059] Furthermore, in the present invention, these green charging wireless sensor nodes (intra-area nodes) that are closer to the base station are designed to be wireless sensor nodes with two batteries (main battery and auxiliary battery) and energy transfer function, called energy relays. The specific structure is as follows Figure 3As shown in the figure. The receiving antenna receives the electromagnetic waves emitted by the green energy far-field wireless charging base station, and the rectifier circuit of the energy receiving system converts them into direct current (DC) and stores them in the battery. The DC power is first stored in the main battery, and then in the secondary battery after the main battery is fully charged, until the charging cycle of the green energy far-field wireless charging base station ends or the secondary battery is fully charged. When the charging cycle (T) of the green energy far-field wireless charging base station ends, the green energy far-field wireless charging base station enters the green energy collection cycle (ΔT). The energy in the main battery of the energy relay is used to support its normal operation (data collection, processing, and forwarding). The energy in the secondary battery is transmitted to the edge node that is not fully charged through the transmitting antenna to replenish its energy, thereby extending the operation time of the edge node and reducing the node mortality rate of the sensor network.

[0060] Preferably, the distance between the energy relay node and the green energy far-field wireless charging base station is shorter than the distance between the edge node and the green energy far-field wireless charging base station.

[0061] Preferably, when the green energy far-field wireless charging base station charges all the sensor nodes within the charging cycle, the calculation formula for the charging power of the sensor nodes is:

[0062]

[0063] Among them, P t is the transmission power of the green energy far-field wireless charging base station, G0 is the transmitting antenna gain of the green energy far-field wireless charging base station, is the receiving antenna gain of the sensor node, η is the receiving circuit rectification efficiency of the sensor node, L p is the polarization loss between the transmitting antenna and the receiving antenna, The green energy far-field wireless charging base station is connected to the k-th sensor node v k distance, λ is the wavelength of electromagnetic waves used for energy transmission; P 0，vk is the charging power of the sensor node.

[0064] Preferably, when the green energy far-field wireless charging base station transmits energy to the edge node during the green energy collection period, the calculation formula for the charging power obtained by the edge node from the energy relay node is:

[0065]

[0066] in, and They are energy relay nodes v i The transmit power and transmit antenna gain, is the energy relay node vi and edge node v j The distance between them.

[0067] Preferably, the edge node v j From the energy relay node v i The formula for calculating the maximum energy obtained is:

[0068]

[0069] in, is the energy relay node v i The amount of power received from the secondary battery.

[0070] In this embodiment, the Friis formula is used as the electromagnetic wave propagation model. When the green energy far-field wireless charging base station charges all sensor nodes during the charging cycle, the sensor node v k The charging power is expressed as:

[0071]

[0072] Among them, P t is the transmitting power of the green energy far-field wireless charging base station, G0 is the transmitting antenna gain of the green energy far-field wireless charging base station, is the sensor node receiving antenna gain, η is the sensor node receiving circuit rectification efficiency, L p is the polarization loss between the transmitting antenna and the receiving antenna, Green energy far-field wireless charging base station to sensor node v k The distance, λ is the wavelength of electromagnetic waves used for energy transmission. Similarly, when the green energy base station enters the green energy collection cycle, the energy relay transmits energy to the edge node, and the edge node v j From the energy relay v i The obtained charging power is expressed as:

[0073]

[0074] in, and They are energy relay v i The transmit power and transmit antenna gain, is the energy relay v i and edge node v j Therefore, the edge node v j Can be relayed from energy v i The maximum energy obtained can be expressed as:

[0075]

[0076] in, is the energy relay v i The amount of power received from the secondary battery.

[0077] This embodiment further provides an energy relay matching method for an energy relay green wireless charging system, which is applied to the above energy relay green wireless charging system. The energy relay matching method includes:

[0078] Any edge node in the circular area is taken as the first node, denoted as Among them, the ray from the center O to this edge node is expressed as The ray from the center O to other edge nodes is represented by Ov j ,ray With ray Ov j The angle between

[0079] according to All the edge nodes are sorted from small to large, and the edge nodes after sorting are represented as j=1,2,...,J;

[0080] Based on the sorting, each consecutive n edge nodes are divided into a group to obtain H edge node groups; each edge node group occupies a subregion, and the boundary between two adjacent subregions is a ray from the center of the circle to the midpoint of the two closest edge nodes in the two adjacent subregions;

[0081] Dividing the circular area into a plurality of sector-shaped sub-areas according to the boundary;

[0082] Determine the two adjacent fan-shaped sub-areas and Energy relay nodes and Quantity size, if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the Node replenish energy; is a floor function; if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the network replenish energy;

[0083] The edge nodes in the first sector sub-area are sorted from large to small according to the distance from the edge node to the green energy far-field wireless charging base station, and an energy relay node is assigned to the edge node according to the sorting. The formula of the energy relay node is expressed as: target =arg max(E(v h,i ,v h,1 )); where v h,i is the i-th energy relay node in the h-th sector sub-area, v h,1 is the first edge node in the h-th fan-shaped sub-region;

[0084] When all edge nodes in the first sector sub-area have obtained an energy relay, the next round of allocation is carried out;

[0085] When the allocated energy relay nodes meet the energy requirements of all edge nodes or all energy relays in this sector sub-area are allocated, the relay allocation of this sector sub-area is completed; the same energy relay allocation operation is performed in all sector sub-areas until the energy relay node allocation of the entire circular area is completed.

[0086] Specifically, energy relays (energy relay nodes) can further supplement the energy of edge sensor nodes in sensor networks, extending their operating time and reducing node mortality. On the one hand, the distance between the energy relay and the edge node affects energy transmission efficiency and even largely determines the amount of energy an edge node receives. The maximum energy a single edge node can receive from different energy relays varies. Different energy relay and edge node pairings affect the secondary energy distribution process, thus impacting overall network performance. On the other hand, given the limited capacity of the energy relay's secondary battery, an energy relay only provides energy to one edge node. However, an edge node can draw energy from multiple energy relays based on its energy needs. Therefore, the energy relay and edge node pairing is a many-to-one relationship. Therefore, it is necessary to find an optimal energy relay and edge node matching strategy to achieve optimal network performance.

[0087] As the number of nodes in an area increases, the number of relay points and edge nodes also increases, making it extremely difficult to find a matching strategy with the best pairing effect. Therefore, this paper proposes an energy relay matching strategy to achieve pairing between energy relays and edge nodes. This matching strategy can achieve good performance and low time complexity. The specific process is as follows:

[0088] (1) Sub-region division

[0089] The first step of this matching strategy is to divide the entire circular charging area into multiple sector-shaped sub-areas, thereby reducing the number of relays and edge nodes in each sub-area. Without significantly destroying the distance characteristics, a better pairing result can be found with lower time complexity.

[0090] First, a random edge node is selected from the entire area as the first node, denoted as The ray from the center O to this edge node is expressed as The ray from the center O to other edge nodes is represented by Ov j ,ray With ray Ov j The angle between according to Sort all edge nodes from small to large, and the edge nodes after sorting are represented as j = 1, 2, ..., J. Then, according to this order, each consecutive n edge nodes are divided into a group, a total of H groups, so that the edge nodes in each group are adjacent in position.

[0091] Next, after the edge node groups are divided, the sub-area division can be performed. Each edge node group occupies a sub-area, and the boundary between two adjacent sub-areas is the ray from the center of the circle to the midpoint of the two closest edge nodes in the two sub-areas. After determining the boundaries of all sub-areas, the entire circular charging area can be divided into multiple sector-shaped sub-areas, and the energy relays will be divided into the corresponding sub-areas (sector-shaped sub-areas), and they will be responsible for charging other edge nodes in their sub-areas. Figure 4 As shown (the sub-areas described later are all fan-shaped sub-areas).

[0092] (2) Energy relay balance

[0093] After subregions are formed, each subregion will contain n edge nodes and several energy relays. Because all nodes are randomly distributed, the number of energy relays in different subregions can vary significantly. In subregions with more energy relays, the energy relays have excess power, while in subregions with fewer energy relays, the energy relays may not be able to fully charge all edge nodes in the subregion. Therefore, this solution will perform energy relay balancing in adjacent subregions to minimize the difference in the number of energy relays between adjacent subregions.

[0094] For two adjacent sub-regions and The number of their relay nodes is expressed as and if Then the sub-region The closest to the boundary of the two sub-regions Energy relays are divided into sub-areas In the The edge nodes in the is the floor function). Conversely, if Then the sub-region The closest to the boundary between the two sub-regions Energy relays are divided into sub-areas In the The edge nodes in the network replenish energy.

[0095] (3) Energy relay distribution

[0096] After the above two steps are completed, the matching of energy relays and edge nodes can be started. First, in the first sub-area, all edge nodes are sorted from large to small according to their distance to the green energy far-field wireless charging base station. The farther the edge node is from the green energy far-field wireless charging base station, the less energy it has, the higher the ranking, and the higher the priority it has when allocating energy relays. After the sorting is completed, an energy relay is first assigned to the edge node ranked 1. This relay is the relay that can provide the maximum energy to this edge node among the existing energy relays in this sub-area, which can be expressed as:

[0097] v target =arg max(E(v h,i ,v h,1 ))

[0098] Among them, v h,i is the i-th relay in the h-th sub-area, v h,1 is the first edge node in the hth sub-area. Energy relays are then allocated to other edge nodes according to the same rules. Once all edge nodes in the area have received an energy relay, the first round of energy relay allocation ends and the next round of allocation begins. When the allocated energy relays meet the energy needs of all edge nodes or all energy relays in the sub-area are allocated, relay allocation for the sub-area is complete. The same energy relay allocation operation is repeated in all sub-areas until energy relay allocation is complete for the entire circular charging area, achieving matching between energy relays and edge nodes.

[0099] The specific energy relay matching strategy algorithm is as follows:

[0100]

[0101]

[0102] The beneficial effects of the present invention are as follows:

[0103] First, the green energy-based far-field wireless charging solution proposed in this invention can use green energy collected by a green energy harvesting device to charge wireless sensors, thus meeting the energy needs of the sensor network while saving energy and reducing the environmental damage caused by traditional power generation methods. Second, the energy relay solution proposed in this invention can transfer excess energy collected by sensor nodes closer to the base station to edge nodes to replenish their energy, improving energy utilization and extending the operating time of edge nodes. This prevents some edge nodes from running out of power and "dying" before the next charging cycle, thereby reducing the node mortality rate of the entire sensor network. Furthermore, the energy relay matching strategy proposed in this invention, after three steps: sub-region division, energy relay balancing, and energy relay allocation, can achieve matching between energy relays and edge nodes while simultaneously ensuring low time complexity and preserving the location characteristics of sensor nodes. This allows for finding suitable energy relays for more edge nodes in need of energy replenishment, maximizing the energy utilization of the energy relays and reducing the node mortality rate of the sensor network.

[0104] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. The methods disclosed in the embodiments are described briefly because they correspond to the systems disclosed in the embodiments. For relevant parts, refer to the description of the systems.

[0105] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. An energy relay green wireless charging system, characterized in that: include: Green energy far-field wireless charging base station and multiple sensor nodes; The sensor nodes are randomly distributed in a circular area with the green energy far-field wireless charging base station as the center; The working cycle of the green energy far-field wireless charging base station includes a charging cycle and a green energy collection cycle that are cyclically cycled. The green energy far-field wireless charging base station is used to collect green energy during the charging cycle, convert the green energy into electrical energy, and use the electrical energy to charge the sensor node based on electromagnetic radiation. The green energy far-field wireless charging base station is also used to collect the green energy during the green energy collection cycle and stop powering the sensor node. The sensor nodes include energy relay nodes and edge nodes; the energy relay nodes have both sensing and energy relay functions, namely, they are used to collect, process and transmit environmental data, and send the collected energy to the edge nodes during the green energy collection cycle; The edge node receives and stores energy transmitted by the green energy far-field wireless charging base station and the energy relay node, and simultaneously collects, processes and transmits back environmental data; An energy relay matching method for an energy relay green wireless charging system applied to the above energy relay green wireless charging system is characterized by comprising: Any edge node in the circular area is taken as the first node, denoted as Among them, the ray from the center O to this edge node is expressed as The ray from the center O to other edge nodes is represented by Ov j ,ray With ray Ov j The angle between them is expressed as according to All the edge nodes are sorted from small to large, and the edge nodes after sorting are represented as Based on the sorting, each consecutive n edge nodes are divided into an edge node group, thereby obtaining H edge node groups after division; each edge node group occupies a subregion, and the boundary between two adjacent subregions is a ray from the center O to the midpoint of the two closest edge nodes in the two adjacent subregions; Dividing the circular area into a plurality of sector-shaped sub-areas according to the boundary; Determine the two adjacent fan-shaped sub-areas and The number of energy relay nodes and Size, if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the Node replenish energy; is a floor function; if Then the fan-shaped sub-area The closest to the boundary of the two fan-shaped sub-regions Energy relay nodes are divided into sector-shaped sub-areas In the example, the energy relay nodes are divided to serve the sector sub-areas. The edge nodes in the network replenish energy; The edge nodes in the first sector sub-area are sorted from large to small according to the distance from the edge node to the green energy far-field wireless charging base station, and an energy relay node is assigned to the edge node according to the sorting. The formula of the energy relay node is expressed as: target =argmax(E(v h,i ,v h,1 )); where v h,i is the i-th energy relay node in the h-th sector sub-area, v h,1 is the first edge node in the h-th fan-shaped sub-region; When all edge nodes in the first sector sub-area have obtained an energy relay, the next round of allocation is carried out; When the allocated energy relay nodes meet the energy requirements of all edge nodes or all energy relays in this fan-shaped sub-area are allocated, the relay allocation of this fan-shaped sub-area is completed; the same energy relay allocation operation is performed in all other fan-shaped sub-areas until the energy relay node allocation of the entire circular area is completed.

2. The energy relay matching method of the energy relay green wireless charging system according to claim 1, characterized in that: The green energy far-field wireless charging base station includes: a green energy collection device, a battery and a base station antenna; The green energy collection device is connected to the battery and the base station antenna respectively. The green energy collection device is used to collect the green energy and convert the green energy into direct current electricity; the battery is used to store the direct current electricity; the base station antenna is used to use the direct current electricity to emit electromagnetic waves to charge the sensor node.

3. The energy relay matching method of the energy relay green wireless charging system according to claim 2, characterized in that: The green energy collection device includes a solar power generation device and a wind power generation device; the solar power generation device and the wind power generation device are both connected to the battery; the green energy includes wind energy and solar energy.

4. The energy relay matching method of the energy relay green wireless charging system according to claim 1, characterized in that: The energy relay node includes: an energy receiving system, a receiving antenna, a switch module, a main battery, a secondary battery, a sensor, an energy transmitting system and a transmitting antenna; The receiving antenna is connected to the energy receiving system, and the energy receiving system is connected to the main battery and the secondary battery respectively through the switch module; the main battery is connected to the sensor; the secondary battery is connected to the energy transmitting system, and the energy transmitting system is connected to the transmitting antenna; The energy receiving system is used to receive the electric energy transmitted by the green energy far-field wireless charging base station through the receiving antenna, and charge the main battery through the switch module; the main battery is used to power the sensor and support the sensor to collect, process and transmit data; the secondary battery is used to store the electric energy transmitted by the green energy far-field wireless charging base station and send it to the edge node through the energy transmission system.

5. The energy relay matching method of the energy relay green wireless charging system according to claim 1, characterized in that: The distance between the energy relay node and the green energy far-field wireless charging base station is shorter than the distance between the edge node and the green energy far-field wireless charging base station.

6. The energy relay matching method of the energy relay green wireless charging system according to claim 1, characterized in that: When the green energy far-field wireless charging base station charges all the sensor nodes within the charging cycle, the calculation formula for the charging power of the sensor nodes is: Among them, P t is the transmission power of the green energy far-field wireless charging base station, G0 is the transmitting antenna gain of the green energy far-field wireless charging base station, is the receiving antenna gain of the sensor node, η is the receiving circuit rectification efficiency of the sensor node, L p is the polarization loss between the transmitting antenna and the receiving antenna, The green energy far-field wireless charging base station is connected to the k-th sensor node v k The distance, λ is the wavelength of electromagnetic waves used for energy transmission; is the charging power of the sensor node.

7. The energy relay matching method of the energy relay green wireless charging system according to claim 6, characterized in that: When the green energy far-field wireless charging base station sends energy to the edge node during the green energy collection period, the calculation formula for the charging power obtained by the edge node from the energy relay node is: in, and They are energy relay nodes v i The transmit power and transmit antenna gain, is the energy relay node v i and edge node v j The distance between them.

8. The energy relay matching method of the energy relay green wireless charging system according to claim 7, characterized in that: Edge node v j From the energy relay node v i The formula for calculating the maximum energy obtained is: in, is the energy relay node v i The amount of power received from the secondary battery.

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