JP2019531682A - Compact high-efficiency design of near-field power transmission system - Google Patents

Abstract

Disclosed herein is an embodiment of a near-field power transfer system that includes antenna elements constructed or printed in close proximity to each other in a serpentine arrangement. In a serpentine arrangement, adjacent antenna elements conduct currents that flow in opposite directions. This current flow completely or almost completely cancels any far-field RF radiation generated by the antenna or otherwise produced by the electromagnetic effects of the current flow. In other words, there is a second current flowing through the second cancellation path that cancels far field radiation generated by the first current flowing through the first path with respect to the first current flowing through the first path. May exist. Thus, there may be no radiation of power to the far field. However, such cancellation may not occur in the near-field effective range where power transmission can occur between the transmitter and the receiver. In addition, the ground plane can prevent power leakage from the back of the transmitter and / or receiver. [Selection] Figure 1A

Description

  [0001] The present application relates generally to wireless power charging systems, and more particularly to near-field radio frequency (RF) antennas for transmitting or receiving power.

  [0002] Electronic devices such as laptop computers, smart phones, portable game devices, tablets, or others require power to operate. As is generally understood, electronic devices are frequently charged at least once a day, or more than once a day for electronic devices that are frequently used or consume large amounts of power. Such work is tedious and can be burdensome for the user. For example, a user may need to carry a charger in case the electronic device is decharged. In addition, some users must find an available power source to connect to the electronic device, which is inconvenient and time consuming. Finally, some users must plug into a wall or some other power source so that the electronic device can be charged. Due to such operations, the electronic device may not be used or may not be carried during charging.

  [0003] Some conventional solutions include inductive charging pads, which may use magnetic induction coils or resonant coils. As understood in the art, such a solution is that the electronic device is (i) placed at a specific location on the inductive charging pad, and (ii) the magnetic field has a specific orientation. Therefore, it still needs to be placed in a specific orientation for power supply. Furthermore, inductive charging units require large coils in both devices (ie, the charger and the device charged by the charger), which is undesirable for reasons of size and cost, for example. There is. Thus, if the electronic device is not placed on the inductive charging pad in the correct orientation, it may not be fully charged or charged. Also, if the electronic device is not charged as expected after using the charging mat, the user may be frustrated, which may impair the reliability of the charging mat or make it unacceptable to the user. .

  [0004] Another solution uses far-field RF wave transmission to create some energy by constructive interference of RF waves at a remote location for charging the device. However, such a solution is more suitable for specific applications and configurations. This is because typically far-field RF wave transmission solutions use multiple antenna arrays and circuits to achieve RF wave phase and amplitude control. Furthermore, far-field antennas may not be efficient for near-field charging systems. Some antennas, such as patch antennas, have been used for near-field power transmission. However, the generated power is not concentrated in a specific area within the near field distance of the transmitter, but rather can leak in all directions, so the patch antenna also has low power transfer efficiency in the near field .

  [0005] Accordingly, there is a need in the art to address the above-mentioned drawbacks of far-field and near-field antennas and to construct near-field RF field antennas with high coupling efficiency.

  [0006] The system disclosed herein addresses the aforementioned problems and can also provide numerous other benefits.

  [0007] (A1) In some embodiments, a near-field radio frequency (RF) power transmission system is provided, the near-field RF power transmission system being disposed above or below the first surface of the substrate, A first antenna element configured to flow a first current in a first direction during a first period to generate a first RF radiation; and on the first surface of the substrate or Disposed below and configured to generate a second RF radiation by passing a second current in a second direction opposite to the first direction during the first period, and as a result A far field portion of the second RF radiation is a second antenna element that offsets the far field portion of the first RF radiation and a ground plane disposed above or below the second surface of the substrate. The second surface includes a grounding surface that is opposite to the first surface.

  [0008] (A2) In some embodiments of the near-field RF power transfer system of A1, the system is a via that penetrates the ground plane and supplies the first current and the second current. A via that accommodates a feed line configured to do.

  [0009] (A3) In some embodiments of the near-field RF power transfer system of A1, the system is a first via that penetrates the ground plane so as to supply the first current. A first via that accommodates the first feed line configured and a second via that penetrates the ground, the second feed line configured to supply the second current Containing a second via.

  [0010] (A4) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element and the second antenna element are segments of a spiral antenna.

  (A5) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element is a segment of a first pole of a dipole antenna, The second antenna element is a segment of the second pole of the dipole antenna.

  (A6) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element and the second antenna element are segments of a loop antenna.

  [0013] (A7) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element and the second antenna element are loop antennas including concentric loops. Is a segment.

  [0014] (A8) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element and the second antenna element are segments of a monopole antenna. .

  [0015] (A9) In some embodiments of the near-field RF power transmission system of any one of A1 to A3, the first antenna element and the second antenna element include two spiral poles. This is a segment of a dipole antenna.

  [0016] (A10) In some embodiments of the near-field RF power transfer system of any one of A1 to A3, the first antenna element and the second antenna element are segments of a hierarchical spiral antenna. is there.

  [0017] (A11) In some embodiments of the near-field RF power transmission system of any one of A1 to A10, the ground plane is constructed of a homogeneous metal sheet of copper or a copper alloy.

  [0018] (A12) In some embodiments of the near-field RF power transmission system of any one of A1 to A10, the ground plane is arranged in a shape selected from the group consisting of a loop, a spiral, and a mesh. Constructed with metal pieces.

  [0019] (A13) In some embodiments of the near-field RF power transmission system of any one of A1 to A12, the first antenna element and the second antenna element are constructed of copper or a copper alloy. The

  [0020] (A14) In some embodiments of the near-field RF power transmission system of any one of A1 to A13, the substrate includes a metamaterial having a predetermined permeability or permittivity.

  [0021] (A15) In some embodiments of the near-field RF power transmission system of any one of A1 to A14, the ground plane is generated by the first antenna element and the second antenna element. It is configured to reflect at least a portion of the RF radiation.

  [0022] (A16) In some embodiments of the near-field RF power transmission system of any one of A1 to A15, the ground plane is generated by the first antenna element and the second antenna element. Configured to cancel at least a portion of the RF radiation.

  (A17) In some embodiments of the near-field RF power transmission system of any one of A1 to A16, the power transmission system is configured as a power receiver.

  (A18) In some embodiments of the near-field RF power transmission system of any one of A1 to A16, the power transmission system is configured as a power transmitter.

  [0025] (A19) In some embodiments, a method of near-field RF power transfer is also provided, the method including connecting the first antenna element to the first antenna element through one or more vias through a ground plane. Supplying a first current such that the second antenna generates a first RF radiation, and a second antenna element such that the second antenna generates a second RF radiation. The first current is directed in a first direction, and the second current is directed in a second direction opposite to the first direction, so that the first current is The far field portion of the second RF radiation cancels the far field portion of the first RF radiation, and the first antenna element and the second antenna element are disposed above or below the first surface of the substrate. And the grounding surface is a second surface opposite to the first surface of the substrate. Or downward, and below the first antenna element and the second antenna element are arranged.

  [0026] (A20) In some embodiments of the near-field RF power transmission system of A19, the ground plane, the first antenna element, the substrate, and the second antenna element are each a near-field power transmission. Part of the system, this near-field power transmission system is configured according to any one of A1-A18.

[0027] The accompanying drawings constitute a part of this specification and illustrate embodiments of the subject matter disclosed herein.
[0028] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0028] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0029] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0029] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0029] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0029] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0030] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0031] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0032] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0033] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0034] FIG. 1 is a schematic diagram of an exemplary system according to one embodiment. [0035] FIG. 2 is a schematic diagram of an exemplary system according to one embodiment. [0036] FIG. 2 is a schematic diagram of an exemplary system according to one embodiment. [0036] FIG. 2 is a schematic diagram of an exemplary system according to one embodiment.

  [0037] Reference will now be made to the exemplary embodiments illustrated in the drawings and specific language will be used herein to describe them. However, it will be understood that it is not intended to limit the scope of the claims or the present disclosure thereby. Changes in the features and further modifications of the invention exemplified herein, as well as additional applications of the principles of the subject matter exemplified herein, will occur to those skilled in the art who have obtained this disclosure. Should be considered within the scope of the disclosed subject matter. The present disclosure is described in detail herein with reference to embodiments illustrated in the drawings that form a part of this specification. Other embodiments may be used and / or other changes may be made without departing from the spirit or scope of the present disclosure. The exemplary embodiments described in the detailed description are not intended to limit the subject matter presented herein.

  [0038] Various embodiments of a power transfer system having high power transfer efficiency in near-field RF-based power transfer coupling are disclosed herein. The power transfer efficiency of transmitters and receivers in a power transfer system can be defined as a percentage or ratio that associates the amount of power transmitted or generated by the transmitter with the amount of power collected by the receiver. . The power transfer efficiency may depend on the combination of transmitter and receiver. If the transmitter and receiver are well coupled, most of the power transmitted by the transmitter's one or more transmit antennas is concentrated on the receiver's one or more receive antennas. On the other hand, if the transmitter and receiver are not well coupled, relatively little power is concentrated on the receiver antenna and power is lost due to leakage in an undesirable direction. Therefore, it is desirable to have a more fully coupled power transmitter and receiver in which the majority of electromagnetic force is captured or otherwise concentrated between the transmitter and receiver.

  [0039] Embodiments of the near-field power transfer system described herein can include antenna elements constructed or printed in close proximity to each other in a serpentine arrangement. In a serpentine arrangement, adjacent antenna elements conduct currents flowing in opposite directions. This current flow completely or almost completely cancels any far-field RF radiation generated by the antenna or otherwise generated by the electromagnetic effects of the current flow. In other words, there is a second current flowing through the second cancellation path that cancels the far-field radiation generated by the first current flowing through the first path with respect to the first current flowing through the first path. May exist. Thus, there may be no radiation of power to the far field. However, such cancellation may not occur in the near-field effective range where power transmission can occur between the transmitter and the receiver. One skilled in the art will recognize that when one or more solutions of Maxwell's equations for time-varying electric and magnetic fields generated by currents flowing in opposite directions are opposite to each other, far-field electromagnetic radiation is It will be appreciated that it is canceled out and that near-field electromagnetic radiation is not canceled out. Those skilled in the art should also understand that the near field coverage is defined by the presence of electromagnetic forces in the immediate vicinity of or adjacent to the power transmission system. Those skilled in the art will further understand the near-field / far-field distinction. For example, the near field may refer to the immediate vicinity of the antenna element and may also include a radiating near field (Fresnel) region, and the far field may refer to an area beyond the immediate vicinity of the antenna element.

  [0040] The near-field power transmission system embodiments described herein may include a ground plane behind the antenna. In the case of a near-field power transmission system that functions as a transmitter, the ground plane functions as a reflector for electromagnetic waves generated by the transmitter antenna, for example, so that power is not transmitted behind the transmission antenna of the power transmission system. There are things to do. Similarly, in the case of a near-field power transmission system that functions as a receiver, the ground plane may prevent received electromagnetic waves from radiating from the back side of the receiver. Thus, having one or more ground planes concentrates electromagnetic forces between the transmitter and receiver by preventing leakage of power from the backside of the transmitter and / or receiver, or Can be captured.

  [0041] The antenna can be constructed in various shapes such as a monopole, a serpentine monopole, a dipole, a serpentine dipole, a spiral, a loop, and a concentric loop. The antenna may also be constructed with a composite configuration such as a spiral dipole. Further, there may be a hierarchical antenna, for example, an antenna having a first spiral dipole at a first hierarchical level and a second spiral dipole at a second hierarchical level above the first hierarchical level. . In some embodiments, a single ground plane may be provided at the lowest hierarchical level. In other embodiments, each hierarchical level may include a ground plane. A composite or hierarchical structure may be required for wideband and / or multiband designs. For example, a non-hierarchical or non-composite structure can be very efficient at a first frequency and a first distance between a transmitter and a receiver, but inefficient at other frequencies and distances. There is something wrong. By incorporating more complex structures, such as composite structures and hierarchical structures, efficiency can be increased over a wide range of frequencies and distances.

  [0042] In some embodiments, a transmit antenna and a corresponding receive antenna may have to be mirror images of each other or symmetrical. In other words, the receiving antenna may have the same or nearly the same shape and / or dimensions as the corresponding transmitting antenna. Such similarity can ensure better coupling and thus provide higher power transfer efficiency. However, in other embodiments, the transmit antenna and the receive antenna may not be symmetric with respect to each other. Furthermore, in the case of dissimilar pairs, the antennas disclosed herein may be paired with other antennas (eg, patches, dipoles, slots). In these cases, the near-field coupling efficiency may still be acceptable for certain applications. Various types of transmit antennas may be combined with various types of receive antennas.

  [0043] In conventional systems, as the frequency decreases and the wavelength increases, the paired antennas may have to be extended. In the embodiments of the near-field power transmission system described herein, a small antenna can also be realized. For example, in many conventional systems, a half-wave dipole antenna used to transmit and / or receive 900 MHz electromagnetic waves typically extends from one end of the antenna to the other, typically 33. 3 centimeters (cm) or approximately 1 foot (ft). However, in the embodiments described herein, such a result can be achieved using a smaller form factor. With the serpentine arrangement disclosed herein, the antennas can be folded back or spiraled together. Thus, a long antenna can be printed or constructed in a relatively small housing. For example, a transmitter / receiver operating at a very low frequency, eg, 400 MHz, can be miniaturized from about 6 millimeters (mm) × 6 mm to about 14 mm × 14 mm antenna dimensions. Furthermore, the near-field power transfer system disclosed herein has a very high power transfer efficiency compared to transmitters and receivers known in the art.

  [0044] The near-field power transmission system disclosed herein can be used in electronic devices such as mobile phones, clothing, and toys. For example, the first power transfer system may be part of or associated with a transmitter embedded in the charging mat, and the second power transfer system may be a receiver embedded in the mobile phone. Or may be associated with it. When the mobile phone is placed close to the charging mat, the transmitter can transmit power to the receiver. In some embodiments, the near field power transfer system may be used in combination with a far field power transfer system. For example, a mobile phone can have both a near-field receiver and a far-field receiver. When the mobile phone is placed on a charging mat with a near field transmitter, the near field receiver in the mobile phone can receive power from the near field transmitter. When the mobile phone is separated from the charging mat and placed at a different location, the far field receiver in the mobile phone can receive power from the far field transmitter.

  FIG. 1A is a top perspective view of a schematic drawing of an exemplary near field power transfer system 100. FIG. 1B is a bottom perspective view of a schematic drawing of an exemplary near-field power transfer system 100. The power transmission system 100 may include a top surface 101, a bottom surface 102, and a side wall 103. In some embodiments, the housing that houses the components of the power transfer system 100 may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 101 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 103 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0046] The power transfer system 100 can emit RF energy when the power transfer system 100 is adjacent to a second power transfer system (not shown), and thus can transmit power. Thus, the power transmission system 100 can be a “transmission side” to function as a power transmitter, and the power transmission system 100 can be a “reception side” to function as a power receiver. it can. In some embodiments, if the power transfer system 100 is associated with a transmitter, the power transfer system 100 (or a subcomponent of the power transfer system 100) may be integrated into the transmitter device, or It may be wired externally to the transmitter. Similarly, in some embodiments, if the power transfer system 100 is associated with a receiver, the power transfer system 100 (or subcomponents of the power transfer system 100) may be integrated into the receiver device. Well, or it may be wired externally to the receiver.

  The substrate 107 can be disposed in a space defined between the top surface 101, the side wall 103, and the bottom surface 102. In some embodiments, the power transfer system 100 may not include a housing and the substrate 107 may include the top surface 101, the sidewall 103, and the bottom surface 102. The substrate 107 may include any material, such as a metamaterial, that can accommodate, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or generate radiation and can also function as a thin reflector.

  [0048] The antenna 104 may be constructed above or below the top surface 101. When the power transfer system 100 is associated with a power transmitter, the antenna 104 can be used to transmit electromagnetic waves. Alternatively, when the power transfer system 100 is associated with a power receiver, the antenna 104 can be used to receive electromagnetic waves. In some embodiments, the power transfer system 100 can operate as a transceiver and the antenna 104 can both transmit and receive electromagnetic waves. The antenna 104 can be constructed of materials such as metals, alloys, metamaterials, and composite materials. For example, the antenna 104 can be made of copper or a copper alloy. The antenna 104 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 100 shown in FIGS. 1A and 1B, the antenna 104 is constructed in the shape of a spiral that includes antenna segments 110 disposed in close proximity to each other. The currents flowing through the antenna segment 110 can be in opposite directions. For example, when current flows in the antenna segment 110b from left to right in FIG. 1A, the current in each of the antenna segments 110a and 110c may flow from right to left. As the current flows in the opposite direction, the electromagnetic radiation cancels each other in the far field of the power transfer system 100. In other words, the far field electromagnetic radiation generated by the one or more antenna segments 110 on the left side of the imaginary line 115 is caused by the far field electromagnetic radiation generated by the one or more antenna segments 110 on the right side of the imaginary line 115. Offset. Therefore, power may not leak in the far field of the power transmission system 100. However, such cancellation may not occur in the near-field effective region of the power transfer system 100 where power transmission may occur.

  [0049] The power transfer system 100 may include a ground plane 106 at or above the bottom surface 102. The ground plane 106 can be formed of a material such as a metal, an alloy, and a composite material. In one embodiment, the ground plane 106 can be formed of copper or a copper alloy. In some embodiments, the ground plane 106 may be constructed of a homogeneous sheet of material. In other embodiments, the ground plane 106 may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 105 that carries a feed line (not shown) to the antenna may penetrate the ground plane 106. The feeder line can supply current to the antenna 104. In some embodiments, the ground plane 106 may be electrically connected to the antenna 104. In some embodiments, the ground plane 106 may not be electrically connected to the antenna 104. In such a mounting, an insulating area 108 that insulates the via 105 from the ground plane 106 may be constructed between the via 105 and the ground plane 106. In some embodiments, the ground plane 106 can function as a reflector for electromagnetic waves generated by the antenna 104. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 100 by canceling and / or reflecting a transmission image formed beyond the bottom surface. The electromagnetic wave transmitted from the upper surface 101 or toward the upper surface 101 can be enhanced by reflecting the electromagnetic wave by the ground surface. Therefore, electromagnetic force may not leak from the bottom surface 102.

  Accordingly, due to the presence of the antenna 104 and the ground plane 106, electromagnetic waves transmitted or received by the power transmission system 100 accumulate in the near field of the system 100. Leakage of the system 100 to the far field is minimal.

  [0051] FIG. 2A schematically illustrates a top perspective view of an exemplary near-field power transfer system 200 according to one embodiment of the present disclosure. In some embodiments, the power transfer system 200 may be part of or associated with a power transmitter. In other embodiments, power transfer system 200 may be part of or associated with a power receiver. The power transfer system 200 may include a housing defined by a top surface 201, a bottom surface (not shown), and a sidewall 203. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 201 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 203 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0052] The substrate 207 can be placed in a space defined between the top surface 201, the side wall 203 and the bottom surface 202. In some embodiments, the power transfer system 200 may not include a housing and the substrate 207 may include a top surface 201, a sidewall 203, and a bottom surface 202. The substrate 207 may comprise any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate an electrical current conducting wire. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or generate radiation and can also function as a thin reflector.

  [0053] An antenna 204 can be constructed above or below the top surface 201. When the power transfer system 200 is part of or associated with a power transmitter, the antenna 204 can be used to transmit electromagnetic waves. Alternatively, the antenna 204 can be used to receive electromagnetic waves when the power transfer system 200 is part of or associated with a power receiver. In some embodiments, the power transfer system 200 can operate as a transceiver and the antenna 204 can both transmit and receive electromagnetic waves. The antenna 204 can be constructed of materials such as metals, alloys, metamaterials, and composite materials. For example, the antenna 204 can be made of copper or a copper alloy. The antenna 204 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 200 shown in FIG. 2A, the antennas 204 are constructed in the shape of a spiral that includes antenna segments positioned in close proximity to each other. A signal supply line (not shown) can be connected to the antenna 204 through the via 205.

  [0054] FIG. 2B schematically illustrates a side view of an exemplary power transfer system 200. FIG. As shown, the upper metal layer can form the antenna 204 and the lower metal layer can form the ground plane 206. The substrate 207 can be disposed between the upper metal layer and the lower metal layer. The substrate 207 may comprise a material such as FR4, metamaterial, or any other material known in the art. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may have to be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or generate radiation and can also function as a thin reflector.

  FIG. 2C schematically shows a top perspective view of the antenna 204. The antenna 204 includes a connection point 209 for a feed line (not shown) that passes through the via 205. FIG. 2D schematically shows a side perspective view of the ground plane 206. In one embodiment, the ground plane 206 comprises a homogeneous metal layer. In other embodiments, the ground plane 206 may include structures such as strips, meshes, and grids, and may not be completely homogeneous. The ground plane 206 can also include a socket 209 through which the via 205 passes. The ground plane 206 can also include an insulating region 210 around the socket 209 that insulates the socket 209 from other portions of the ground plane 206. In some embodiments, the ground plane may have an electrical connection to a line that passes through the via, and the insulating region 210 may not be required.

  [0056] FIG. 3 schematically illustrates a top perspective view of an exemplary near-field power transfer system 300 according to one embodiment of the present disclosure. In some embodiments, the power transfer system 300 may be part of or associated with a power transmitter. In other embodiments, power transfer system 300 may be part of or associated with a power receiver. The power transfer system 300 may include a housing defined by a top surface 301, a bottom surface (not shown), and a sidewall 303. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 301 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 303 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0057] The substrate 307 can be placed in a space defined between the top surface 301, the side wall 303, and the bottom surface 302. In some embodiments, the power transfer system 300 may not include a housing and the substrate 307 may include a top surface 301, a side wall 303, and a bottom surface 302. The substrate 307 may comprise any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0058] An antenna 304 can be constructed above or below the top surface. When the power transfer system 300 is part of or associated with a power transmitter, the antenna 304 can be used to transmit electromagnetic waves. Alternatively, the antenna 304 may be used to receive electromagnetic waves when the power transfer system 300 is part of or associated with a power receiver. In some embodiments, the power transfer system 300 can operate as a transceiver and the antenna 304 can both transmit and receive electromagnetic waves. The antenna 304 can be constructed of materials such as metals, alloys, metamaterials, and composite materials. For example, the antenna 304 can be made of copper or a copper alloy. The antenna 304 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 300 shown in FIG. 3, the antenna 304 is constructed in the form of a dipole that includes a first serpentine pole 309a and a second serpentine pole 309b. A first feed line (not shown) to the first serpentine pole 309a may be carried by the first via 305a, and a second feed line (not shown) to the second meander pole 309b is May be carried by the second via 305b. The first power supply line can supply current to the first serpentine pole 309a, and the second power supply line can supply current to the second serpentine pole 309b. The first serpentine pole 309a includes antenna segments 310 disposed in close proximity to each other, and the second serpentine pole 309b includes antenna segments 311 also disposed in close proximity to each other. The currents flowing through adjacent antenna segments 310, 311 can be in opposite directions. For example, when current flows from the left to the right in FIG. 3 in the antenna segment 310b, the current in each of the antenna segments 310a and 310c may flow from the right to the left. The far field electromagnetic radiation generated by the power transfer system 300 cancels each other due to the reverse flow of current across any number of antenna segments 310 of the power transfer system 300. Additionally or alternatively, the far field electromagnetic radiation generated by the antenna segment 310 of the first pole 309a can be offset by the electromagnetic radiation generated by the antenna segment 311 of the second pole 309b. It should be understood that far-field cancellation can occur over any number of segments 310, 311 and / or over any number of poles 309. Therefore, power may not leak in the far field of the power transmission system 300. However, such cancellation may not occur in the near field effective area of the power transfer system 300 where power transfer may occur.

  [0059] The power transfer system 300 may include a ground plane (not shown) on the bottom surface or above the bottom surface. The ground plane can be formed of materials such as metals, alloys, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 305 that carries the feeder to the antenna may penetrate the ground plane. In some embodiments, the ground plane may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 304. In such mounting, an insulating area that insulates the via 305 from the ground plane may be constructed between the via 305 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 304. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 300 by canceling and / or reflecting a transmission image formed beyond the bottom surface. By reflecting the electromagnetic wave by the ground plane, the electromagnetic wave transmitted from the antenna 304 to the upper surface 301 or toward the upper surface 301 can be strengthened. Therefore, electromagnetic force may not leak from the bottom surface.

  [0060] FIG. 4 schematically illustrates a top perspective view of an exemplary near-field power transfer system 400 according to one embodiment of the present disclosure. In some embodiments, power transfer system 400 may be part of or associated with a power transmitter. In other embodiments, power transfer system 400 may be part of or associated with a power receiver. The power transfer system 400 may include a housing defined by a top surface 401, a bottom surface (not shown), and a sidewall 103. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 401 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 403 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0061] The substrate 407 can be placed in a space defined between the top surface 401, the side wall 403, and the bottom surface 402. In some embodiments, the power transfer system 400 may not include a housing and the substrate 407 may include a top surface 401, a sidewall 403, and a bottom surface 402. The substrate 407 may include any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or generate radiation and can also function as a thin reflector.

  [0062] An antenna 404 may be constructed above or below the top surface 401. When the power transfer system 400 is part of or associated with a power transmitter, the antenna 404 can be used to transmit electromagnetic waves. Alternatively, the antenna 404 can be used to receive electromagnetic waves when the power transfer system 400 is part of or associated with a power receiver. In some embodiments, the power transfer system 400 can operate as a transceiver, and the antenna 404 can both transmit and receive electromagnetic waves. The antenna 404 can be constructed of materials such as metals, alloys, and composite materials. For example, the antenna 404 can be made of copper or a copper alloy. The antenna 404 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 400 shown in FIG. 4, the antennas 404 are constructed in the shape of a loop that includes loop segments 410 disposed in close proximity to each other. The currents flowing through adjacent loop segments 410 can be in opposite directions. For example, if current flows in the first loop segment 410a from left to right in FIG. 4, the current in the second loop segment 410b may flow from right to left. In the far field of the power transfer system 400, the electromagnetic radiation cancels each other by the current flowing in the opposite direction. Therefore, power may not leak out in the far field of the power transmission system 400. However, such cancellation may not occur in the near field effective area of the power transfer system 400 where power transfer may occur.

  [0063] The power transfer system 400 may include a ground plane (not shown) on the bottom surface or above the bottom surface. The ground plane can be formed from materials such as metals, alloys, metamaterials, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 405 that carries a feed line (not shown) to the antenna may penetrate the ground plane. The feeder line can provide current to the antenna 404. In some embodiments, the ground plane 106 may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 404. In such mounting, an insulating area that insulates the via 405 from the ground plane may be constructed between the via 305 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 404. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 400 by canceling and / or reflecting a transmission image formed beyond the bottom surface. The electromagnetic wave transmitted from the upper surface 401 or toward the upper surface 401 can be strengthened by reflecting the electromagnetic wave by the ground surface. Therefore, electromagnetic force may not leak from the bottom surface.

  [0064] FIG. 5 schematically illustrates a top perspective view of an exemplary near-field power transfer system 500 according to one embodiment of the present disclosure. In some embodiments, the power transfer system 500 may be part of or associated with a power transmitter. In other embodiments, power transfer system 500 may be part of or associated with a power receiver. In other embodiments, power transfer system 500 may be part of or associated with a transceiver. The power transfer system 500 may include a housing defined by a top surface 501, a bottom surface (not shown), and a sidewall 503. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 501 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 503 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0065] The substrate 507 can be placed in a space defined between the top surface 501, the side wall 503, and the bottom surface 502. In some embodiments, the power transfer system 500 may not include a housing and the substrate 507 may include a top surface 501, a sidewall 503, and a bottom surface 502. The substrate 507 may include any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0066] An antenna 504 may be constructed above or below the top surface 501. When the power transfer system 500 is part of or associated with a power transmitter, the antenna 504 can be used to transmit electromagnetic waves. Alternatively, the antenna 504 can be used to receive electromagnetic waves when the power transfer system 500 is part of or associated with a power receiver. In some embodiments, the power transfer system 500 can operate as a transceiver, and the antenna 504 can both transmit and receive electromagnetic waves. A feed line (not shown) to the antenna 504 may be carried by the via 505. The feeder line can provide current to the antenna 504. The antenna 504 can be constructed of materials such as metals, alloys, metamaterials, and composite materials. For example, the antenna 504 can be made of copper or a copper alloy. The antenna 504 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 500 shown in FIG. 5, the antennas 504 are constructed in the form of concentric loops that include antenna segments 510 disposed in close proximity to each other. As shown in FIG. 5, a single concentric loop may include two of the antenna segments 510. For example, the innermost loop may include a first antenna segment 510c to the right of an imaginary line 512 that bisects the loop, and a corresponding second antenna segment 510c ′ to the left of the imaginary line 512. May include. The currents flowing through adjacent antenna segments 510 can be in opposite directions. For example, if current flows in the antenna segments 510a ', 510b', 510e 'from left to right in FIG. 5, the current in each of the antenna segments 510a, 510b, 510c may flow from right to left. Electromagnetic radiation cancels each other in the far field of the power transfer system 500 due to the current flowing in the opposite direction. Therefore, power may not be transmitted to the far field of the power transmission system 500. However, such cancellation may not occur in the near field effective area of the power transfer system 500 where power transfer may occur. Those skilled in the art know that electromagnetic radiation cancels in the far field, and that such cancellation does not occur in the near field, Maxwell's for time-varying electric and magnetic fields generated by currents flowing in opposite directions. It will be understood that it is defined by one or more solutions of the equation. Those skilled in the art should further understand that the near-field effective range is defined by the presence of electromagnetic forces in the immediate vicinity of the power transfer system 500.

  [0067] The power transfer system 500 may include a ground plane (not shown) on or above the bottom surface. The ground plane can be formed of materials such as metals, alloys, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 505 that carries the feeder to the antenna may penetrate the ground plane. In some embodiments, the ground plane may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 504. In such mounting, an insulating area that insulates the via 505 from the ground plane may be constructed between the via 305 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 504. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 500 by canceling and / or reflecting a transmission image formed beyond the bottom surface. The electromagnetic wave transmitted from the upper surface 501 or toward the upper surface 501 can be enhanced by reflecting the electromagnetic wave by the ground plane. Therefore, electromagnetic force may not leak from the bottom surface.

  [0068] FIG. 6 schematically illustrates a top perspective view of an exemplary near-field power transfer system 600 according to one embodiment of the present disclosure. In some embodiments, power transfer system 600 may be part of or associated with a power transmitter. In other embodiments, power transfer system 600 may be part of or associated with a power receiver. The power transfer system 600 may include a housing defined by a top surface 601, a bottom surface (not shown), and a sidewall 603. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 601 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 603 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0069] The substrate 607 may be disposed in a space defined between the top surface 601, the sidewall 603, and the bottom surface 602. In some embodiments, the power transfer system 600 may not include a housing and the substrate 607 may include a top surface 601, a sidewall 603, and a bottom surface 602. The substrate 607 may comprise any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0070] An antenna 604 may be constructed above or below the top surface 601. When the power transfer system 600 is part of or associated with a power transmitter, the antenna 604 can be used to transmit electromagnetic waves. Alternatively, antenna 604 can be used to receive electromagnetic waves when power transfer system 600 is part of or associated with a power receiver. In some embodiments, the power transfer system 600 can operate as a transceiver, and the antenna 604 can both transmit and receive electromagnetic waves. The antenna 604 can be constructed of materials such as metals, alloys, and composite materials. For example, the antenna 604 can be made of copper or a copper alloy. The antenna 604 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 600 shown in FIG. 6, the antenna 604 is constructed in the shape of a monopole. Via 605 can carry a feed line (not shown) to antenna 604. The feeder line can provide current to the antenna 604.

  [0071] The power transfer system 600 may include a ground plane (not shown) on the bottom surface or above the bottom surface. The ground plane can be formed of materials such as metals, alloys, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 605 that carries the feed line to the antenna 604 may penetrate the ground plane. In some embodiments, the ground plane may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 604. In such mounting, an insulating area that insulates the via 605 from the ground plane may be constructed between the via 605 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 604. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 600 by canceling and / or reflecting a transmission image formed beyond the bottom surface. By reflecting the electromagnetic waves by the ground plane, the electromagnetic waves transmitted from the antenna 604 to the upper surface 601 or toward the upper surface 601 can be enhanced. Therefore, electromagnetic force may not leak from the bottom surface.

  [0072] FIG. 7 schematically illustrates a top perspective view of an exemplary near-field power transfer system 700 according to one embodiment of the present disclosure. In some embodiments, the power transfer system 700 may be part of or associated with a power transmitter. In other embodiments, power transfer system 700 may be part of or associated with a power receiver. The power transfer system 700 may include a housing defined by a top surface 701, a bottom surface (not shown), and the sidewall 103. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 701 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 703 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0073] The substrate 707 can be disposed in a space defined between the top surface 701, the side wall 703, and the bottom surface 702. In some embodiments, the power transfer system 700 may not include a housing and the substrate 707 may include a top surface 701, a side wall 703, and a bottom surface 702. The substrate 707 may comprise any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0074] An antenna 704 can be constructed above or below the top surface 701. When the power transfer system 700 is part of or associated with a power transmitter, the antenna 704 can be used to transmit electromagnetic waves. Alternatively, antenna 704 can be used to receive electromagnetic waves when power transfer system 700 is part of or associated with a power receiver. In some embodiments, the power transfer system 700 can operate as a transceiver, and the antenna 704 can both transmit and receive electromagnetic waves. The antenna 704 can be constructed of materials such as metals, alloys, and composite materials. For example, the antenna 704 can be made of copper or a copper alloy. Via 705 can carry a feed line (not shown) to the antenna. The feeder line can provide current to the antenna 704. The antenna 704 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 700 shown in FIG. 7, the antennas 704 are constructed in the shape of a monopole that includes antenna segments 710 disposed in close proximity to each other. The currents flowing through adjacent antenna segments 710 can be in opposite directions. For example, when current flows from the left to the right in FIG. 7 in the antenna segment 710b, the current in each of the antenna segments 710a and 710c may flow from the right to the left. Electromagnetic radiation cancels each other out in the far field of the power transfer system 700 due to the current flowing in the opposite direction. Accordingly, power transmission may not occur in the far field of the power transmission system 700. However, such cancellation may not occur in the near field effective area of the power transfer system 700 where power transfer may occur. As will be appreciated by those skilled in the art, the cancellation of electromagnetic radiation in the far field, and the absence of such cancellation in the near field, is a time-varying electric field generated by currents flowing in opposite directions. And is defined by one or more solutions of Maxwell's equations for magnetic fields. Those skilled in the art will further appreciate that the near field effective range is defined by the presence of electromagnetic forces in the immediate vicinity of the power transfer system 700. The power transfer system 700 can include a ground plane (not shown) on the bottom surface or above the bottom surface. The ground plane can be formed of materials such as metals, alloys, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 705 that carries the feed line to the antenna 704 may penetrate the ground plane. In some embodiments, the ground plane may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 704. In such mounting, an insulating area that insulates the via 705 from the ground plane may be constructed between the via 705 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 704. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 700 by canceling and / or reflecting a transmission image formed beyond the bottom surface. By reflecting the electromagnetic wave by the ground plane, the electromagnetic wave transmitted from the upper surface 701 or toward the upper surface 701 can be enhanced. Therefore, electromagnetic force may not leak from the bottom surface.

  [0075] FIG. 8 schematically illustrates a top perspective view of an exemplary near-field power transfer system 800 according to one embodiment of the present disclosure. In some embodiments, power transfer system 800 may be part of or associated with a power transmitter. In other embodiments, power transfer system 800 may be part of or associated with a power receiver. The power transfer system 800 may include a housing defined by a top surface 801, a bottom surface (not shown), and a sidewall 803. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 801 may allow the electromagnetic wave to pass with minimal obstruction, and the sidewall 803 may block the electromagnetic wave by attenuation, absorption, reflection, or other techniques known in the art.

  [0076] The substrate 807 can be placed in a space defined between the top surface 801, the side wall 803, and the bottom surface 802. In some embodiments, the power transfer system 800 may not include a housing and the substrate 807 may include a top surface 801, a sidewall 803, and a bottom surface 802. The substrate 807 may include any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0077] An antenna 804 can be constructed above or below the top surface 801. When the power transfer system 800 is part of or associated with a power transmitter, the antenna 804 can be used to transmit electromagnetic waves. Alternatively, antenna 804 can be used to receive electromagnetic waves when power transfer system 800 is part of or associated with a power receiver. In some embodiments, the power transfer system 800 can operate as a transceiver, and the antenna 804 can both transmit and receive electromagnetic waves. The antenna 804 can be constructed of materials such as metals, alloys, and composite materials. For example, the antenna 804 can be made of copper or a copper alloy. The antenna 804 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 800 shown in FIG. 8, the antenna 804 is constructed as a composite dipole comprising a first spiral pole 820a and a second spiral pole 820b. A first power supply line for supplying current to the first spiral pole 820a can be provided through the first via 805a, and a second power supply line for supplying current to the second spiral pole 820b can be provided by the second via Vias 805b can be provided. The antenna segments in each of the spiral poles 820 can cancel each other's electromagnetic radiation in the far field generated by the spiral dipole 820, thereby reducing the transmission of power to the far field. For example, the antenna segments in the first spiral pole 820a can cancel far field electromagnetic radiation generated by each other. Additionally or alternatively, the far field radiation generated by the one or more antenna segments of the first spiral pole 820a is the far field radiation generated by the one or more antenna segments of the second spiral pole 820b. Can be offset by field radiation. Those skilled in the art know that electromagnetic radiation cancels in the far field, and that such cancellation does not occur in the near field, Maxwell's for time-varying electric and magnetic fields generated by currents flowing in opposite directions. It will be understood that it is defined by one or more solutions of the equation.

  [0078] The power transfer system 800 may include a ground plane (not shown) on the bottom surface or above the bottom surface. The ground plane can be formed of materials such as metals, alloys, and composite materials. In one embodiment, the ground plane can be formed of copper or a copper alloy. In some embodiments, the ground plane may be constructed with a homogeneous sheet of material. In other embodiments, the ground plane may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 805 that carries the feeder to the antenna may penetrate the ground plane. In some embodiments, the ground plane may be electrically connected to the antenna. In some embodiments, the ground plane may not be electrically connected to the antenna 804. In such mounting, an insulating area that insulates the via 805 from the ground plane may be constructed between the via 805 and the ground plane. In some embodiments, the ground plane can function as a reflector for electromagnetic waves generated by the antenna 804. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 800 by canceling and / or reflecting a transmission image formed beyond the bottom surface. The electromagnetic wave transmitted from the upper surface 801 or toward the upper surface 801 can be strengthened by reflecting the electromagnetic wave by the ground plane. Therefore, electromagnetic force may not leak from the bottom surface.

  [0079] The composite antenna 804 may be required for wideband and / or multiband designs. For example, a non-composite structure can be very efficient at a first frequency and a first distance between a transmitter and a receiver, but can be inefficient at other frequencies and distances. . By incorporating more complex structures such as composite antenna 80, efficiency can be increased over a wide range of frequencies and distances.

  [0080] FIGS. 9A and 9B schematically illustrate a top perspective view and a side perspective view, respectively, of an exemplary near-field power transfer system 900 according to one embodiment of the present disclosure. In some embodiments, power transfer system 900 may be part of or associated with a power transmitter. In other embodiments, power transfer system 100 may be part of or associated with a power receiver. The power transfer system 900 may include a housing defined by a top surface 901, a bottom surface 902, and a sidewall 903. In some embodiments, the housing may be constructed of a material that minimizes interference with the passage of electromagnetic waves. In other embodiments, different portions of the housing may be constructed of materials with different electromagnetic properties such as permeability and dielectric constant. For example, the top surface 901 may allow electromagnetic waves to pass with minimal obstruction, and the sidewall 903 may block the electromagnetic waves by attenuation, absorption, reflection, or other techniques known in the art.

  [0081] The substrate 907 may be disposed in a space defined between the top surface 901, the side wall 903, and the bottom surface 902. In some embodiments, the power transfer system 900 may not include a housing and the substrate 907 may include a top surface 901, a sidewall 903, and a bottom surface 902. The substrate 907 may include any material, such as a metamaterial, that can house, conduct, reflect, absorb, or otherwise accommodate electrical current conducting wires. Metamaterials can be a wide variety of synthetic materials designed to obtain the desired permeability and dielectric constant. At least one of permeability and dielectric constant may be based on power transfer requirements and / or constraints on compliance with government regulations. The metamaterial disclosed herein can receive radiation or transmit radiation and can also function as a thin reflector.

  [0082] The power transfer system may include a hierarchical antenna 904, which may be constructed above or below the top surface 901. When the power transfer system 900 is part of or associated with a power transmitter, the antenna 904 can be used to transmit electromagnetic waves. Alternatively, antenna 904 may be used to receive electromagnetic waves when power transmission system 900 is part of or associated with a power receiver. In some embodiments, the power transfer system 900 can operate as a transceiver and the antenna 904 can both transmit and receive electromagnetic waves. The antenna 904 can be constructed of materials such as metals, alloys, and composite materials. For example, the antenna 904 can be made of copper or a copper alloy. The antenna 904 can be constructed to have various shapes based on power transmission requirements. In the exemplary system 900 shown in FIGS. 9A and 9B, the antenna 104 is constructed in a hierarchical spiral structure having a level 0 hierarchical antenna 904a and a level 1 hierarchical antenna 904b. Each of the hierarchical antennas 904 may include antenna segments that have currents flowing in opposite directions to cancel far-field radiation. For example, antenna segments in level 0 hierarchical antenna 904a can cancel far field electromagnetic radiation generated by each other. Additionally or alternatively, the far field radiation generated by the one or more antenna segments of the level 0 hierarchical antenna 904a is the far field radiation generated by the one or more antenna segments of the level 1 hierarchical antenna 904b. Can be offset by field radiation. A feed line (not shown) to the antenna is carried through the via 905. The feeder line can supply current to the antenna 904.

  [0083] The power transfer system 900 may include a ground plane 906 on the bottom surface 902 or above the bottom surface 902. The ground plane 906 can be formed of a material such as a metal, an alloy, and a composite material. In one embodiment, the ground plane 906 can be formed of copper or a copper alloy. In some embodiments, the ground plane 906 may be constructed of a homogeneous sheet of material. In other embodiments, the ground plane 906 may be constructed using pieces of material arranged in shapes such as loops, spirals, and meshes. A via 905 that carries the feed line to the antenna may penetrate the ground plane 906. In some embodiments, the ground plane 906 may be electrically connected to one or more of the antennas 904. In some embodiments, the ground plane 906 may not be electrically connected to the antenna 904. In such a mounting, an insulating area 908 that insulates the via 905 from the ground plane 906 may be constructed between the via 905 and the ground plane 906. In some embodiments, the ground plane 906 can function as a reflector for electromagnetic waves generated by the antenna 904. In other words, the ground plane may not allow electromagnetic transmission beyond the bottom surface of the power transfer system 900 by canceling and / or reflecting a transmission image formed beyond the bottom surface. By reflecting the electromagnetic wave by the ground plane, the electromagnetic wave transmitted by the antenna 904 from the upper surface 901 or toward the upper surface 901 can be enhanced. Therefore, electromagnetic force may not leak from the bottom surface 902. In some embodiments, there may be multiple ground planes and there may be a ground plane for each of the hierarchical antennas 904. In some embodiments, the hierarchical antenna has different feed lines that are carried through multiple vias.

  [0084] Hierarchical antenna 904 may be required for wideband and / or multiband designs. For example, a non-hierarchical structure can be very efficient at a first frequency and a first distance between a transmitter and a receiver, but can be inefficient at other frequencies and distances. . Incorporating more complex structures such as hierarchical antennas 904 can increase efficiency over a wide range of frequencies and distances.

  [0085] The foregoing method descriptions and process flow diagrams are provided merely as illustrative examples and require or imply that the steps of the various embodiments must be performed in the order presented. It is not intended to be. The steps in the foregoing embodiments may be performed in any order. Terms such as “then”, “next”, etc. are not intended to limit the order of the steps. These terms are only used to guide the reader through the description of the method. Although a process flow diagram may describe the operations as sequential steps, many of the operations can be performed in parallel or simultaneously. Furthermore, the order of operations can be rearranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, or the like. If the process corresponds to a function, the end of the process may correspond to returning the function to the calling function or main function.

  [0086] The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the embodiments described herein and variations thereof. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein will not depart from the spirit or scope of the subject matter disclosed herein. The present invention can be applied to other embodiments. Accordingly, this disclosure is not intended to be limited to the embodiments shown herein, but is most consistent with the following claims and the principles and novel features disclosed herein. Should be given a wide range.

  [0087] While various aspects and embodiments have been disclosed, other aspects and embodiments are also contemplated. The various aspects and embodiments disclosed are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims (20)

A near-field radio frequency (RF) power transmission system,
A first antenna disposed above or below the first surface of the substrate and configured to flow a first current in a first direction to generate first RF radiation during a first period Elements and
Arranged above or below the first surface of the substrate, and during the first period, a second current is passed in a second direction opposite to the first direction to produce a second RF radiation. A second antenna element configured to generate, so that a far field portion of the second RF radiation substantially cancels a far field portion of the first RF radiation;
A near-field RF power transmission system comprising: a ground plane disposed above or below the second surface of the substrate, wherein the second surface is opposite the first surface. .   The near-field RF power of claim 1, further comprising a via that penetrates the ground plane and that houses a feed line configured to supply the first current and the second current. Transmission system. A first via penetrating the ground plane, the first via accommodating a first feeder configured to supply the first current;
The second via penetrating the ground plane, further comprising a second via that accommodates a second feed line configured to supply the second current. Near-field RF power transmission system.   The near field RF power transfer system of claim 1, wherein the first antenna element and the second antenna element are segments of a spiral antenna.   The near-field RF power transfer of claim 1, wherein the first antenna element is a segment of a first pole of a dipole antenna and the second antenna element is a segment of a second pole of the dipole antenna. system.   The near field RF power transfer system of claim 1, wherein the first antenna element and the second antenna element are segments of a loop antenna.   The near-field RF power transfer system of claim 1, wherein the first antenna element and the second antenna element are segments of a loop antenna including concentric loops.   The near field RF power transfer system of claim 1, wherein the first antenna element and the second antenna element are segments of a monopole antenna.   The near field RF power transfer system of claim 1, wherein the first antenna element and the second antenna element are segments of a composite dipole antenna including two spiral poles.   The near-field RF power transmission system according to claim 1, wherein the first antenna element and the second antenna element are segments of a hierarchical spiral antenna.   The near field RF power transfer system of claim 1, wherein the ground plane is constructed of a homogeneous metal sheet of copper or copper alloy.   The near-field RF power transfer system of claim 1, wherein the ground plane is constructed of metal pieces arranged in a shape selected from the group consisting of a loop, a spiral, and a mesh.   The near-field RF power transmission system according to claim 1, wherein the first antenna element and the second antenna element are constructed of copper or a copper alloy.   The near-field RF power transmission system according to claim 1, wherein the substrate includes a metamaterial having a predetermined magnetic permeability or dielectric constant.   13. A neighborhood according to any one of claims 1 to 12, wherein the ground plane is configured to reflect at least a portion of the RF radiation generated by the first antenna element and the second antenna element. Field RF power transmission system.   13. A neighborhood according to any one of claims 1 to 12, wherein the ground plane is configured to cancel at least a portion of the RF radiation generated by the first antenna element and the second antenna element. Field RF power transmission system.   The near-field RF power transmission system according to claim 1, wherein the power transmission system is configured as a power receiver.   The near-field RF power transmission system according to claim 1, wherein the power transmission system is configured as a power transmitter. A near-field radio frequency (RF) power transmission method comprising:
Through one or more vias through the ground plane of the near field RF power transfer system,
Providing a first current to a first antenna element of the near field RF power transfer system such that the first antenna generates a first RF radiation;
Providing a second current to a second antenna element of the near field RF power transfer system such that the second antenna generates second RF radiation;
The first current is directed in a first direction and the second current is directed in a second direction opposite to the first direction, so that a far field portion of the second RF radiation is Substantially canceling the far-field portion of the first RF radiation;
The first antenna element and the second antenna element are disposed above or below the first surface of the substrate;
The method wherein the ground plane is disposed above or below a second surface opposite the first surface of the substrate. 20. A method according to claim 19, wherein the near-field RF power transmission system is configured according to any one of claims 1-18.

Images