Combined near-field and far-field antennas

Abstract

One example discloses a combined near-field and far-field antenna configured to be coupled to a conductive main surface, the combined near-field and far-field antenna comprising: a first feed point configured to be coupled to a far-field transceiver; a second feed point configured to be coupled to a near-field transceiver; a first conductive antenna surface; a first filter having a first interface coupled to the first feed point and the first conductive antenna surface, and a second interface coupled to the second feed point; wherein the first filter is configured to attenuate far-field signals transmitted between the first conductive antenna surface and the far-field transceiver to prevent them from being received by the near-field transceiver; and wherein the first filter is configured to transmit near-field signals between the near-field transceiver and the first conductive antenna surface.

Description

Technical Field

[0001] This specification relates to systems, methods, apparatus, devices, articles of manufacture, and instructions for use with antennas. Background Art

[0002] This paper discusses in-body and out-of-body communication and other wireless network devices based on near-field electromagnetic induction (NFEMI), in which transmitters and receivers communicate in the far field via magnetic (H) and electric (E) field coupling and / or using RF plane waves propagating through free space. Summary of the Invention

[0003] According to an exemplary embodiment, a combined near-field and far-field antenna configured to be coupled to a conductive main surface includes: a first feed point configured to be coupled to a far-field transceiver; a second feed point configured to be coupled to a near-field transceiver; a first conductive antenna surface; and a first filter having a first interface coupled to the first feed point and the first conductive antenna surface, and a second interface coupled to the second feed point; wherein the first filter is configured to attenuate far-field signals transmitted between the first conductive antenna surface and the far-field transceiver to prevent them from being received by the near-field transceiver; and wherein the first filter is configured to transmit near-field signals between the near-field transceiver and the first conductive antenna surface.

[0004] In another exemplary embodiment, the surface of the first conductive antenna is a planar plate.

[0005] In another exemplary embodiment, the surface of the first conductive antenna is a planar spiral coil or a non-planar helical coil.

[0006] In another exemplary embodiment, the first conductive antenna surface is a planar spiral structure or a non-planar helical structure, the first conductive antenna surface having a first end coupled to a set of electronic circuits and a second end uncoupled and terminating in free space.

[0007] In another exemplary embodiment, the surface of the first conductive antenna is a monopole far-field antenna.

[0008] In another exemplary embodiment, the monopole far-field antenna has a length greater than or equal to 1 / 4 wavelength of the far-field signal carrier frequency.

[0009] In another exemplary embodiment, the surface of the first conductive antenna is oriented such that the far-field signal current is substantially perpendicular to the conductive main surface.

[0010] In another exemplary embodiment, a coil antenna portion coupled to the near-field transceiver and configured as a near-field magnetic antenna is also included.

[0011] In another exemplary embodiment, the near-field signal is approximately 50 MHz or lower; the far-field signal is approximately 1 GHz or higher.

[0012] In another exemplary embodiment, the first filter is an RF choke coil.

[0013] In another exemplary embodiment, the first filter is at least one of a ferrite bead, a coil surrounded by ferrite material, or a parallel circuit tuned to an RF frequency.

[0014] In another exemplary embodiment, the first filter has a low-pass filter topology or a notch filter topology.

[0015] In another exemplary embodiment, the first filter (L) has an inductance of approximately 12 nH.

[0016] In another exemplary embodiment, the transceiver is configured to time-division multiplex the near-field signal and the far-field signal.

[0017] In another exemplary embodiment, the transceiver is configured to alternately turn on and off to time-division multiplex near-field signals and far-field signals.

[0018] In another exemplary embodiment, a second filter is further included, coupled between the first conductive antenna surface and the far-field transceiver; wherein the second filter is configured to attenuate near-field signals transmitted between the first conductive antenna surface and the near-field transceiver to prevent them from being received by the far-field transceiver; wherein the second filter is configured to transmit far-field signals between the far-field transceiver and the first conductive antenna surface.

[0019] In another exemplary embodiment, a reference plane is also included; wherein the reference plane is coupled to the far-field transceiver; wherein the reference plane is configured to be located closer to the conductive main surface than the first conductive antenna surface.

[0020] In another exemplary embodiment, the conductive main surface is at least one of a human body, an ear, a wrist, or an opening.

[0021] In another exemplary embodiment, the combined antenna is embedded in the earpiece, and the surface of the first conductive antenna forms the outer surface of the earpiece.

[0022] In another exemplary embodiment, a second conductive antenna surface coupled to the near-field transceiver is also included; and wherein the first conductive antenna surface is farther from the conductive main structure than the second conductive antenna surface.

[0023] The above discussion is not intended to represent every exemplary embodiment or every implementation within the scope of the current or future claims. The accompanying drawings and detailed descriptions also illustrate various exemplary embodiments.

[0024] A more comprehensive understanding of the various exemplary embodiments can be achieved by considering the following specific embodiments in conjunction with the accompanying drawings. Attached Figure Description

[0025] Figure 1 This is an example of a near-field electromagnetic induction (NFEMI) antenna.

[0026] Figure 2 This is an example of combining near-field and far-field antennas.

[0027] Figure 3A , 3B The images 3C and 3D illustrate two exemplary wireless devices including an exemplary combined antenna.

[0028] Figure 4 This is an exemplary schematic diagram of a combination of near-field and far-field antennas, which are positioned as a first or second wireless device in a user's ear.

[0029] While this disclosure is open to various modifications and substitutions, its details have been shown by way of example in the accompanying drawings and will be described in detail. However, it should be understood that other embodiments are possible besides the specific embodiments described. All modifications, equivalents, and alternative embodiments falling within the spirit and scope of the appended claims are also covered. Detailed Implementation

[0030] In-vivo NFEMI communication utilizes non-propagating quasi-static H-fields and E-fields. Such in-vivo NFEMI devices include an H-field antenna (i.e., a magnetic antenna) that is primarily sensitive to magnetic fields and / or primarily initiates the magnetic field when driven by an electric current. Any E-field component from the H-field antenna is significantly reduced (e.g., reduced by -20 to -60 dB, with a reduction factor of 0.1 to 0.0008 (10% to 0.08%) depending on the antenna design).

[0031] The small-loop antenna is an exemplary H-field antenna and includes a loop antenna with a size much smaller than its operating wavelength. The small-loop antenna does not resonate at the NFEMI carrier frequency but is tuned to resonance via an external reactance. In some exemplary embodiments, the current in the small-loop antenna has the same value at every location in the loop.

[0032] This in-body NFEMI device also includes an E-field antenna (i.e., an electric antenna) that is primarily sensitive to electric fields and / or primarily initiates electric fields when driven by voltage. Any H-field components from the E-field antenna are significantly reduced (e.g., reduced by -20 to -60 dB, with a reduction factor of 0.1 to 0.0008 (10% to 0.08%) depending on the antenna design).

[0033] The short-loaded dipole antenna is an exemplary E-field antenna and includes a short dipole with a size much smaller than the NFEMI carrier frequency, and in some exemplary embodiments, has additional capacitive structures at both ends.

[0034] These near-field quasi-static characteristics are a result of the combination of NFEMI antenna size and its carrier frequency. Most of the near-field energy is stored in the form of magnetic and electric fields, while a small amount of RF energy inevitably propagates in free space.

[0035] Near-field magnetic induction (NFMI) or near-field electro-induction (NFEI) communication can also be used for this type of body communication. The magnetic field in an NFMI device is not coupled to the body, so such a device can be located much further from the body than NFMI or NFEI devices and still ensure communication. However, due to the small size of the magnetic antenna in such an NFMI device, the range of the NFMI device is much shorter than that of an overall NFEI device. Small antenna geometries are effective for both NFMI and NFMI antennas because they minimize radiated waves in free space.

[0036] Figure 1 This is an example of a near-field electromagnetic induction (NFEMI) antenna 100 used in a wireless device. In this example, antenna 100 is an NFEMI antenna. In some exemplary embodiments, antenna 100 includes a coil antenna 105 (i.e., for a magnetic field) and a short-loaded dipole 120 (i.e., for an electric field). The coil antenna 105 includes a ferrite core 110 wound with wire 115. The short dipole 120 includes a first conductive antenna surface 125 and a second conductive antenna surface 130. Antenna 100 feed points 135, 140 are coupled to various transceiver circuits, such as downstream radio transmitter and receiver integrated circuits (RF-ICs) (not shown here). The bandwidth and resonant frequency of antenna 100 can be tuned using reactive components (e.g., capacitor and resistor groups) integrated in the radio IC.

[0037] The short-loaded dipole portion 120 responds to the electric (E) field. The coil antenna portion 105 responds to the magnetic (H) field.

[0038] When the NFEMI antenna 100 is brought close to a body (e.g., a person, object, etc.), the magnetic and electric fields will be largely confined to the body and will not radiate significantly in free space. This enhances the security and confidentiality of this body network communication.

[0039] In various exemplary embodiments, the antenna 100 operates at 50 MHz or below to ensure that the field follows the body profile and that far-field radiation is greatly reduced.

[0040] Some wearable devices, such as smartwatches, include far-field communication modules for external communication with other wireless devices, such as smartphones.

[0041] Wearable devices may also include a near-field communication module as part of a body area network, which may include earbuds and various sensors configured to be placed close to the user's body. Even when the user is listening to music flowing from a smartphone to a smartwatch and then to the earbuds, these sensors can collect body parameters transmitted via the near-field communication to the smartwatch.

[0042] However, in some body area network applications, users may not be equipped with a smartwatch or smart wristband. In this case, another wearable device will need to include a far-field communication module for wireless communication with smartphones and / or other external devices. Including the far-field communication module in the earbud may present problems because the earbud's shape factor is preferably very small.

[0043] Exemplary embodiments of a body-worn device combining near-field and far-field antennas are now discussed. This combined antenna reuses a portion of the near-field antenna for far-field communication, thus requiring little or no additional volume, allowing both antennas to fit the form factor of a small earpiece.

[0044] An exemplary embodiment of this combined / dual-mode antenna may include a first mode for near-field audio and data communication and a second mode for far-field communication (e.g., Bluetooth, BLE, etc.). This combined antenna allows for in-body and external wireless communication of audio, video, and data.

[0045] Figure 2 Example 200 is a combination of near-field and far-field antennas. The combination antenna 200 includes elements of the NFEMI antenna 100 (i.e., a ferrite core 110 wound with wire 115 to form a near-field magnetic antenna, and a first conductive antenna surface 125 and a second conductive antenna surface 130 forming a near-field electric antenna).

[0046] Feed points 135 and 140 are coupled to near-field transceiver 202, which in various exemplary embodiments includes a radio transmitter and receiver integrated circuit (RF-IC) and various reactive components (e.g., capacitor and resistor groups) for adjusting the bandwidth and resonant frequency of NFEMI antenna 100.

[0047] Example 200, which combines near-field and far-field antennas, also includes a far-field transceiver 204, a first filter (L) 206 (e.g., an RF choke coil or a combination of a coil and a capacitor), a second filter 208, a reference plane 210, and feed points 212, 214, and 216.

[0048] The first conductive antenna surface 125 serves both as near-field E-field coupling and as far-field coupling for RF plane waves propagating through free space. In various exemplary embodiments, the first conductive antenna surface 125 may be a planar plate, a planar coil, a coiled coil, or a helical coil.

[0049] In some exemplary embodiments, the dual-use first conductive antenna surface 125 is positioned as far away as possible from the first conductive structure (e.g., the user's skin) to improve near-field electric (E-field) performance while reducing absorption of far-field RF signals by the user's body. In some examples, the first conductive antenna surface 125 may also be oriented such that the far-field antenna current is substantially perpendicular to the conductive main surface (e.g., the user's head).

[0050] The first interface of the first filter 206 is coupled to the first conductive antenna surface 125 and the feed point 212 from the far-field transceiver 204, while the second interface of the first filter (L) 206 is coupled to the feed point 135.

[0051] In near-field mode at lower frequencies (e.g., 10 MHz), the first filter (L) 206 is low impedance, and the near-field transceiver 202 electrically "sees" only the coil antenna portion 105 (small loop antenna, H field) and the short-load dipole portion 120 (i.e., the electric (E) field), as... Figure 1 The second filter 208 is configured to attenuate the signal from the near-field transceiver 202 originating from the far-field transceiver 204.

[0052] In the far-field mode at higher frequencies (e.g., 2.4 GHz), the first filter (L) 206 is high impedance, and the far-field transceiver 204 electrically "sees" the surface 125 of the first conductive antenna only, preventing far-field signals from leaking into the near-field transceiver 202.

[0053] In some exemplary embodiments, the first filter (L) 206 has an inductance of about 12nH for the dual-mode system, wherein 10.6MHz is used for the near-field communication frequency and 2.5GHz (e.g., BT or BLE) is used for the far-field communication frequency.

[0054] The first filter (L) 206 can be a common induction coil, a ferrite bead, a coil surrounded by ferrite material, or a "parallel circuit" tuned to an RF frequency. The first filter (L) 206 can be configured as a low-pass filter or a notch filter.

[0055] The second filter 208 (e.g., including RF matching and near-field filtering circuitry) is coupled between the feed point 212 and the far-field transceiver 204 via the feed point 214. The second filter 208 also isolates the far-field transceiver 204 from the near-field signals of the near-field transceiver 202. The second filter 208 may be configured as a high-pass filter or a notch filter.

[0056] In an exemplary embodiment where the far-field transceiver 204 has balanced input / output, a balancing unit (BALUN) is inserted between the far-field transceiver 204 and the second filter 208.

[0057] In some exemplary embodiments, if near-field and far-field communication are time-division multiplexed (i.e., do not occur simultaneously), the second filter 208 can be removed. Alternatively, various shielding methods can be added to suppress any signal harmonic interference between the two transceivers 202, 204. Transceivers 202, 204 can be alternately turned on and off to prevent interference.

[0058] The far-field transceiver 204 is coupled to a reference plane 210 (e.g., on a printed circuit board) via a feed point 216. In some exemplary embodiments, the reference plane 210 is located in a position shielded from far-field interference (e.g., for an earbud device, the reference plane 210 may be located at a distance from the inner ear canal).

[0059] In some examples, the reference plane 210 is placed at the maximum distance from the first conductive antenna surface 125 to minimize any capacitance between the reference plane 210 and the first conductive antenna surface 125. Alternatively, a dielectric material (e.g., a PCB, a plastic with a low dielectric constant, a gas cavity, etc.) may be placed between the first surface 125 and the reference plane 210.

[0060] Figure 3A , 3B The images 3C and 3D illustrate two exemplary wireless devices 300 and 326, each including an exemplary combined antenna. In an exemplary embodiment, the wireless devices 300 and 326 are earbuds that can be partially or completely covered during use, such as when placed in an earbud in a user's ear canal.

[0061] Figure 3A This is an exemplary side view 302 of a first wireless device 300 having a continuous first conductive antenna surface 316. Figure 3B This is an exemplary axial view 304 of a first wireless device 300 having a continuous first conductive antenna surface 316 (i.e., facing the side opposite to the ear canal).

[0062] Device 300 includes a non-planar outer surface 305 having a magnetic core region 306 and an extension region 308, a speaker 309, a user interface 310, a coil antenna 312 (i.e., a magnetic H-field antenna), a second conductive antenna surface 314 (i.e., an electric E-field antenna), a first conductive antenna surface 316 (i.e., an electric E-field antenna), a battery 318, and electronic circuitry 320 including a carrier (e.g., a printed circuit board).

[0063] In the example, the core region 306 accommodates, for example... Figure 2 and Figure 3A The various functional components are shown. Extension region 308 defines a portion of the non-planar outer surface 305 of wireless device 300, and its contour is adapted to a non-planar surface of the main conductive surface (e.g., a user's ear, in order to provide stable positioning of the earbud embodiment of wireless device 300).

[0064] In some exemplary embodiments, the speaker 309 is configured to be inserted into a user's ear canal. The user interface 310 enables control of the wireless device 300 (e.g., control of different functions of the earbuds) and may include switches, proximity and / or photoelectric sensors responsive to touch and / or gestures from the user.

[0065] Some exemplary embodiments of the coil antenna 312 include a magnetic core and wire windings, wherein the magnetic core is a ferrite material having a diameter of 2 mm and a length of 6 mm, and has at least 20 wire windings.

[0066] In some exemplary embodiments, the second conductive antenna surface 314 includes a lower portion 322 inside the wireless device 300 near the battery and an upper portion 324 closer to the outer surface of the wireless device 300. In some examples, the first conductive antenna surface 316 surrounds the user interface 310, while in other examples, the first conductive antenna surface 316 may have a continuous planar portion behind or in front of the user interface 310.

[0067] In some exemplary embodiments, the first conductive antenna surface 314 and the second conductive antenna surface 316 are flexible metal foils; in other exemplary embodiments, the first conductive antenna surface 314 and the second conductive antenna surface 316 are conductive coatings.

[0068] Battery 318 supplies power to electronic circuitry 320 and is rechargeable or replaceable. In various exemplary embodiments, electronic circuitry 320 includes transceiver circuitry, a receiver integrated circuit (RF-IC), and reactive components (e.g., capacitor and resistor groups). The reactive components (e.g., capacitor and resistor groups) regulate the bandwidth and resonant frequency of device 300. Electronic circuitry 320 may be coupled to a substrate / carrier. The carrier may be a printed circuit board or any flexible material suitable for holding electronic circuitry 320, as well as any mechanical components capable of enabling earbud functionality.

[0069] Figure 3C This is an exemplary side view 328 of a second wireless device 326 having a spiral / helical first conductive antenna surface 316, and Figure 3D This is an exemplary axial view 330 of a second wireless device 326 having a spiral / helical first conductive antenna surface 316 (i.e., facing the side opposite to the ear canal).

[0070] In the exemplary second wireless device 326, the first conductive antenna surface 316 is a planar spiral structure or a non-planar helical structure, having a first end 332 coupled to the electronic circuitry 320 (or coil antenna 312) and an uncoupled second end 334 terminating in free space by forming a monopole RF antenna. The spiral / helical shape can be implemented within the plastic housing of the earbud. In some exemplary embodiments, the distance between the first end 332 and the second end 334 is chosen to have sufficient length to resonate far-field communication frequencies between 1 and 6 GHz.

[0071] Other specific shapes for the first conductive antenna surface 316 are also possible. In a helical embodiment, the first conductive antenna surface 316 can begin to spiral out in various directions from near the user's head. The helical wire can be very thin to produce a very long far-field monopole antenna for more robust far-field communication. More than one such helical wire can also be used in nested configurations or in different geometric planes.

[0072] In near-field mode, the voltage transmitted and / or received by the NFEMI antenna of wireless device 300 is a combination of voltages caused by magnetic H field and electric E field.

[0073] By geometrically aligning the second conductive antenna surface 314 with the main surface (e.g., the user's ear canal), the antenna capacitance (Ca) increases. Therefore, the shape of the extension region 308 conforming to the user's outer ear and the shape of the core region 306 adjacent to the speaker 309 conforming to the user's inner ear increase the capacitance (Ca) of the NFEMI antenna and generate a larger electric field.

[0074] Therefore, even if the direct electric field E generated by the second conductive antenna surface 314 is blocked by the inner ear, the large capacitance (Ca) allows the main conductive surface (e.g., the user's body) to indirectly emit the electric field of the second conductive antenna surface 314.

[0075] Moreover, in near-field mode, by maximizing the distance (d) between the second conductive antenna surface 314 and the first conductive antenna surface 316, a larger electric field is generated and the received voltage (Vrx) is further increased.

[0076] Using these two techniques, robustness of near-field mode NFEMI communication was achieved.

[0077] In far-field mode, the three-dimensional helical winding or planar spiral winding of the first conductive antenna surface 316 generates a long (e.g., equal to or greater than 1 / 4 wavelength) RF antenna for enhanced far-field radiation.

[0078] The electric vector generated by winding 316 has the same orientation as the current flowing through winding 316. When the first conductive antenna surface 316 is positioned perpendicular to the skin of the head (for the earplug), the current has an orientation perpendicular to the skin. Currents parallel to the skin cancel each other out because the current in front of the coil differs from the current behind the coil by 180 degrees.

[0079] In some exemplary embodiments, the antenna gain is between -15 and -5 dBi at 2.5 GHz. This is due to the low radiation resistance (1 to 5 ohms) and low absorption from conductive primary surfaces, such as human tissue. However, for a 0 dBm transmitter output, this is sufficient for a communication range of 10 to 15 meters if you have a sensitive receiver (e.g., -92 dBm).

[0080] Figure 4 This is an exemplary schematic diagram 400 of an exemplary combined near-field and far-field antenna 200 located in a first wireless device 300 or a second wireless device 326 near a first conductive main surface 402 (e.g., the user's head), a second conductive main surface 404 (e.g., the user's outer ear) and / or a third conductive main surface 406 (e.g., the user's inner ear).

[0081] In one exemplary embodiment, a speaker 309 is inserted into the inner ear canal 406 of a user 402, and a first conductive structure 314 is mounted close to the inner ear canal 406 and the outer ear canal 404, while a second conductive structure 316 is positioned to be separate from the inner ear. This configuration of the conductive structures 314, 316 provides a combination of close skin contact with the host and maximum separation between the two conductive structures 314, 316.

[0082] The conductive main surfaces 402, 404, and 406 can typically be any E-field responsive conductive main surface. In various other exemplary embodiments, such conductive main surfaces 402, 404, and 406 can be another part of the human body, a body surface, an opening, a nose, a mouth, or any type of conductive structure.

[0083] Near-field signals from the combined antenna 200 are confined to the vicinity of conductive main surfaces 402, 404, and 406 in transmit mode, and confined to conductive main surfaces 402, 404, and 406 in receive mode.

[0084] In an exemplary embodiment of the near-field mode, the near-field frequency is kept below 50 MHz to ensure that the near-field signal follows the contours of the conductive main surfaces 402, 404, 406, and that the first conductive antenna surface 316 radiates only a small amount of far-field radiation. However, in the far-field mode, the first conductive antenna surface 316 is configured to radiate significant far-field radiation.

[0085] The various instructions and / or operational steps discussed in the above figures can be performed in any order unless a specific order is explicitly specified. Furthermore, those skilled in the art will recognize that while some example groups of instructions / steps have been discussed, the material in this specification can be combined in various ways to produce other examples, and should be understood within the context provided in this specific embodiment.

[0086] In some exemplary embodiments, these instructions / steps are implemented as functional and software instructions. In other embodiments, the instructions may be implemented using logic gates, dedicated chips, firmware, and other hardware forms.

[0087] When instructions are implemented as a set of executable instructions in a non-transient, computer-readable or computer-usable medium, the medium is implemented on a computer or machine programmed with and controlled by the executable instructions. The instructions are loaded to execute on a processor (e.g., one or more CPUs). The processor includes a microprocessor, microcontroller, processor module or subsystem (including one or more microprocessors or microcontrollers) or other control or computing device. A processor may refer to a single component or multiple components. The computer-readable or computer-usable storage medium is considered part of an article (or article of manufacture). An article or article of manufacture may refer to any manufactured single component or multiple components. Non-transient machine or computer-usable media or mediums as defined herein do not include signals, but such media or mediums may be capable of receiving and processing information from signals and / or other transient media.

[0088] It will be readily understood that the components can be arranged and designed in various different configurations as described herein and illustrated in the accompanying drawings. Therefore, the specific implementation of the various embodiments illustrated in the drawings is not intended to limit the scope of this disclosure, but is merely representative of various embodiments. Although various aspects of the embodiments are illustrated in the drawings, the drawings are not necessarily drawn to scale unless explicitly stated otherwise.

[0089] The invention may be practiced in other specific forms without departing from the spirit or essential characteristics thereof. The described embodiments are to be considered in all respects illustrative rather than restrictive. Therefore, the scope of the invention is indicated by the appended claims rather than the specific embodiments described. All variations within the equivalent meaning and scope of the claims are included within the scope of the claims.

[0090] References to features, advantages, or similar language throughout this specification do not imply that all features and advantages achievable with this invention should or should exist in any single embodiment of the invention. Rather, references to features and advantages are to be understood as indicating that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the invention. Therefore, the discussion of features and advantages, and similar language throughout this specification, may, but does not necessarily, refer to the same embodiments.

[0091] Furthermore, the features, advantages, and characteristics described herein can be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize that, based on the description herein, the invention can be practiced without one or more of a particular feature or advantage of a particular embodiment. In other instances, additional features and advantages that may not be present in all embodiments of the invention may be recognized in certain embodiments.

[0092] Throughout this specification, references to "an embodiment," "embodiment," or similar language mean that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the invention. Therefore, the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification may, but not necessarily all, refer to the same embodiment.

Claims

1. A combined near-field and far-field antenna configured to be coupled to a conductive main surface, characterized in that, include: It is configured to be coupled to the first feed point of the far-field transceiver; It is configured to be coupled to the second feed point of the near-field transceiver; The surface of the first conductive antenna; A first filter has a first interface coupled to the first feed point and the surface of the first conductive antenna, and a second interface coupled to the second feed point; The first filter is configured to attenuate the far-field signal transmitted between the surface of the first conductive antenna and the far-field transceiver so as to prevent it from being received by the near-field transceiver. as well as The first filter is configured to transmit near-field signals between the near-field transceiver and the surface of the first conductive antenna, the surface of the first conductive antenna having a first end coupled to a set of electronic circuits and a second end uncoupled and terminating in free space.

2. The antenna according to claim 1: Its features are, The surface of the first conductive antenna is a planar plate.

3. The antenna according to claim 1: Its features are, The surface of the first conductive antenna is a planar spiral coil or a non-planar helical coil.

4. The antenna according to claim 1: Its features are, The surface of the first conductive antenna is a monopole far-field antenna.

5. The antenna according to claim 4: Its features are, The monopole far-field antenna has a length greater than or equal to 1 / 4 wavelength of the far-field signal carrier frequency.

6. The antenna according to claim 1: Its features are, The surface of the first conductive antenna is oriented such that the far-field signal current is perpendicular to the conductive main surface.

7. The antenna according to claim 1: Its features are, It also includes a coil antenna portion coupled to the near-field transceiver and configured as a near-field magnetic antenna.

8. The antenna according to claim 1: Its features are, The near-field signal is less than or equal to 50MHz; and The far-field signal is higher than or equal to 1 GHz.

9. The antenna according to claim 1: Its features are, The first filter is an RF choke coil.

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