DE102015105610B3 - Frequency-selective mass structures - Google Patents

Abstract

The invention relates to a device for wireless charging of a mobile radio device (5) and to the radio coupling thereof, as well as to a vehicle-mounted charging and radio-coupling system with a device for wireless charging of a mobile radio device (5) and to its radio coupling. The device comprises a wireless low-frequency charging device (1) and a high-frequency signal coupling device (2). With the aim of making the wireless low-frequency charging device (1) and the high-frequency signal coupling device (2) combinable in the simplest possible way, the solution according to the invention provides that the high-frequency signal coupling device is a high-frequency coupling structure (20) for the wireless coupling of a high-frequency signal from or to the mobile and a frequency selective structure (30), wherein the frequency selective structure (30) is disposed between the low frequency charger and the high frequency coupling structure (20), the low frequency frequency selective structure (30) being substantially transmissive is and is substantially reflective for the radio frequency.

Description

Technical area

Embodiments of the present invention relate to a device for wireless charging of a mobile device and the radio coupling thereof. Further embodiments relate to a vehicle-mounted charging and radio-coupling system for a mobile radio device.

Technical background

Mobile devices such. B. Mobile phones are equipped with a variety of components with relatively high energy requirements. In the course of ever-increasing demands on performance, there is a tendency in particular in the field of smartphones to powerful microprocessors, high-resolution displays and radio modules, which must maintain efficient and stable radio links in a variety of frequency ranges using various connection protocols. At the same time, the requirement is placed on the mobile devices to be as handy and portable as possible. A hand-limiting component is, for example, the accumulator for mobile power supply.

A mobile device, which is subject to a typical usage behavior in the daily routine, is often in environments in which a charging infrastructure can be provided, for. B. on board a motor vehicle. Conventional wireless charging devices are designed as a charging station or charging cradle and allow easy connection of the mobile device for charging.

In the installation or operating state of conventional wireless charging devices, a surface is formed above a charging device with its associated charging structure on which the mobile device can be stored for performing a charging or partial charging. The loading structure is z. B. a coil, and the energy transfer usually takes place via a low-frequency alternating field.

In order to avoid unnecessary losses or damage, conventional wireless charging devices have a device for detecting non-loadable objects (English: foreign object detection device), which detect whether a foreign object has been deposited on the surface, in particular a metallic foreign object. In this case, the energy transfer is prevented.

Even during a wireless charging process, a stable radio connection between the mobile device to be loaded and a remote station is desirable. In the area of smartphones in particular, user expectations are becoming ever more uninterrupted ("always-on"). Under a variety of conditions, the radiation of a high-frequency signal is limited by the antennas located in or on the mobile device. This can be z. B. when used in a vehicle, in particular motor vehicle be the case, which acts by its large-area metal structures damping the high-frequency field or the radiated or to be received electromagnetic wave.

Wired high frequency signal connectors may be used, but these are impractical and difficult to handle. A coupling structure for the wireless coupling of the high-frequency signal from or to the mobile device, in particular if it is to be compact, has a homogeneous ground surface at a defined distance.

In order to simultaneously charge the accumulator of the mobile device wirelessly and wirelessly couple a high-frequency signal from or to the mobile radio system, a suitable low-frequency charging device and a suitable high-frequency signal coupling device may be provided together. However, in the above-described homogeneous ground plane of the high-frequency signal coupling device, large losses are generated by the low-frequency charger, for example, in the form of eddy currents. The device for detecting non-chargeable objects will recognize the ground surface as a foreign object and not initiate or interrupt a charging process.

There is therefore a need for the simplest possible combinability of wireless charging devices and wireless high-frequency coupling devices.

Summary

In view of the circumstances explained above, a device for wireless charging of a mobile device and the radio coupling thereof according to claim 1 is given.

In addition, a vehicle-mounted charging and Funkkopplungssystem for a mobile device according to claim 9 is given.

According to one embodiment, an apparatus for wireless charging of a mobile device and the radio coupling thereof is specified. The device comprises a low frequency wireless charging device and a high frequency signal coupling device. The high-frequency Signal coupling device in turn has a high-frequency coupling structure for wireless coupling of a high-frequency signal from or to the mobile device. Furthermore, the high-frequency signal coupling device has a frequency-selective structure which is arranged between the low-frequency charging device and the high-frequency coupling structure. The frequency selective structure is substantially transparent to the low frequency and substantially reflective to the high frequency. The frequency-selective structure is at least partially formed as a lattice structure.

According to another embodiment, a vehicle-mounted charging and radio coupling system for a mobile device is specified. The charging and radio coupling system comprises the device for wireless charging of a mobile device and its radio coupling according to one of the embodiments described herein, which is formed in this embodiment as a loading and docking tray. The loading and docking tray can be arranged in the vehicle interior in this embodiment. The high-frequency coupling structure has a connection to an external vehicle antenna.

Advantageous developments, features and details of embodiments are given in the dependent claims, the drawings and the description.

In this description, the terms "low frequency" (abbreviated to NF) and "high frequency" (abbreviated to RF) are used in a form commonly used in electrical engineering.

Low-frequency signals used for wireless charging technology described herein generally have frequencies in the long-wave or long-wave range. The magnetic field component of the LF signals greatly outweighs the distances considered herein. For example, the frequencies of the LF signals are in the range between a few tens and a few hundred kilohertz. Typically, energy is transmitted inductively from the low-frequency charger to a mobile device to be charged.

RF signals described herein are used for radio links, typically for cellular connections of various standards such as GSM, UMTS or LTE. For example, the frequencies of the RF signals are in the range of a few hundred megahertz to a few gigahertz.

The frequencies of the RF signals may, for example, be in the GSM 900 band (P-GSM, E-GSM, R-GSM) or in the GSM 1800 band (DCS 1800). The frequencies of the RF signals can also be in the UMTS 2100 band (band I), for example. The frequencies of the RF signals can also be in the 2.6 GHz LTE band (E-UTRA 7) or in the 800 MHz LTE band (E-UTRA 20), for example.

The frequency ranges of the LF signals described herein and the RF signals described herein therefore generally do not overlap. Typically, the LF frequency ranges and the RF frequency ranges are spaced apart by at least a factor of 1000.

In embodiments, the low frequency signal from the low frequency charging device has frequency components from a first frequency range, and the high frequency signal from and to the high frequency signal coupling device has frequency components from a second frequency range. The high frequency signal is typically a modulated signal occupying some bandwidth around a center frequency. The second frequency range includes the bandwidth with respect to the center frequency, i. H. the center frequency of the second frequency range is the center frequency of the high frequency signal. The second frequency range is higher than the first frequency range and typically without overlaps with it.

In this description, the term "vehicle-bound" is to be understood as meaning that the so-called charging and radio-coupling system can be used in a vehicle, for example, installed in a vehicle. The operation of the charging and radio-coupling system then proceeds using vehicle structures, in particular holding and fastening structures, devices for supplying energy or lines provided on the vehicle, antennas and the like. By "vehicle-bound" is not necessarily meant that the so-called charging and radio-coupling system is firmly and non-removably connected to the vehicle. However, the vehicle-mounted charging and radio coupling system can be firmly connected to the vehicle. Also, it is not necessarily integrated into the vehicle, but may well be integrated into the vehicle.

For the wireless charging function of the mobile device standardized methods can be used. The low frequency charger may be compatible with a variety of mobile phones of different types. On the other hand, various types of antenna structures for HF communication may be used in different mobile device types, ie the antenna structures of a mobile device type may differ from those in other mobile device types. During the design phase, therefore, the corresponding RF radiation behavior of the respective mobile device is taken into account which the high-frequency coupling structure is to be adapted. For example, the geometry of the high-frequency coupling structure, the relative position, the shape, etc. adapted to the respective mobile device.

The same frequency-selective structure can be used for different high-frequency coupling structures, in particular for different geometries of high-frequency coupling structures. The frequency-selective structure and / or the high-frequency coupling structure may be formed in stripline technology on or in a printed circuit board. The frequency-selective structure can act approximately as a ground plane. The term "ground plane" here is not necessarily to be understood as an exact plane is formed. The ground plane or the frequency-selective structure acting approximately as a ground plane represents a mirror plane (an approximately mirror structure of finite extent) for the radio-frequency coupling structure. In embodiments, the radio-frequency coupling structure is designed as an antenna structure, in particular as a planar inverted-F antenna. The ground plane acts z. B. as electrical RF counterweight for the exemplary case that the antenna structure is designed as a quarter-wave radiator.

In embodiments, the high frequency signal coupling device is modular, such that the high frequency coupling structure is replaceable. Alternatively or additionally, in embodiments, the high-frequency signal coupling device is modular, so that the frequency-selective structure is exchangeable. While maintaining the low frequency charger, in embodiments, a modular design can facilitate the interchangeability of the RF components of the device. Simple interchangeability also typically results from the retrofitting of a wireless charging and wireless coupling device to compatibility with a mobile device for compatibility with another mobile device.

In embodiments, the low-frequency charging device has a planar charging structure for low-frequency energy transmission. Typically, the planar charging structure is a flat coil structure. In embodiments, the flat charging structure is formed as a strip line flat coil structure.

In embodiments, the frequency-selective structure and the high-frequency coupling structure are formed in or on one and the same circuit board. Typically, the frequency-selective structure and the high-frequency coupling structure are formed in different planes, preferably in or on different circuit board levels of the same printed circuit board. The respective circuit board plane may be a plane running on the surface of the circuit board. But it can also be a running within the circuit board level, especially when using a multilayer printed circuit board. Connections can be designed as printed circuit board feedthroughs (vias).

In particular, when the frequency-selective structure and the high-frequency coupling structure are formed in stripline technology, such a combination of frequency-selective structure and high-frequency coupling structure in or on one and the same circuit board offers. However, such a combination can also be provided if the frequency-selective structure and the high-frequency coupling structure are not formed in stripline technology. It may result in improved modularity or interchangeability.

In embodiments, the frequency selective structure is formed in multiple levels. The frequency-selective structure is typically formed in or on different circuit board levels of one and the same circuit board. Similarly, the high frequency coupling structure may also be formed in multiple levels, typically in or on different board levels of the same circuit board. There may be a simplification in the production of the frequency-selective structure or the high-frequency coupling structure, in particular in the production of a comparatively fine frequency-selective structure or high-frequency coupling structure using an exposure and etching process or the like.

In embodiments, the high frequency coupling structure is connectable or connected to an electromagnetic radiator. Typically, the electromagnetic radiator is an antenna, in particular an external antenna such. B. an external vehicle antenna. The connectivity or connection is independent of whether the radio frequency coupling structure itself acts as an antenna structure or as a line resonator, as described in more detail below. The radio frequency coupling structure is for RF coupling to the mobile device to be charged in close proximity to the device, while the connectivity or connection to the electromagnetic emitter is typically external to the environment or near electromagnetic field of the device, i. H. in an arrangement of the device in a vehicle z. B. to an external vehicle antenna.

In embodiments, the high frequency coupling structure is an antenna structure educated. At least partially, the high-frequency coupling structure may be formed as a planar inverted F antenna. In embodiments, the high frequency coupling structure may also be formed as a line resonator structure.

Brief description of the drawings

Embodiments of the present invention will be explained below with reference to the drawings, wherein like reference numerals indicate the same or similar regions, parts, components and / or structures.

In the drawings show:

1 a schematic representation of a charging tray with a device according to an embodiment of the invention;

2 a schematic representation of a high-frequency coupling structure, a frequency-selective structure and a charging structure of a device according to an embodiment of the invention, in plan view;

3 the presentation 2 in an exploded perspective view;

4 a multi-level trained frequency-selective structure of a device according to an embodiment of the invention in a perspective view; and

5 the presentation 4 in a perspective exploded view.

Description of the embodiments

1 shows a schematic representation of a charging tray 6 with a device according to an embodiment of the invention. The charging station 6 is in 1 shown only schematically and can be configured for example as a charging tray or the like. It has a housing 7 from a little wave dampening material, on the upper housing surface 8th a storage facility for a mobile device 5 is provided. A deposit process of the exemplary and schematically shown mobile device 5 , especially a smartphone, is in 1 indicated by an arrow.

Inside the case 7 is a device for wireless charging of the mobile device 5 and for radio coupling of the mobile device 5 arranged. The device in turn has a low frequency charger 1 and a high-frequency signal coupling device 2 on. The high frequency signal coupling device 2 lies in the in 1 shown operating position or operating orientation of the charging tray above the low-frequency charger 1 , The high frequency signal coupling device 2 is arranged so that the distance of its upper edge to the upper housing surface 8th is low to a direct or low-attenuation radio coupling of the mobile device 5 to allow.

In the plan view of the in the loading tray 6 out 1 arranged combination of low-frequency charger 1 and high frequency signal coupling means 2 the schematic representation results 2 , A loading structure 10 , a frequency-selective structure 30 and a high frequency coupling structure 20 lie in plan view in partial coverage and provide a combined functionality, ie a wireless charging function for the mobile device 5 and a coupling function for establishing the radio coupling with the mobile device 5 ,

The structure and arrangement of the individual components, ie the charging structure 10 , the frequency-selective structure 30 and the high frequency coupling structure 20 , goes from the schematic perspective exploded view in 3 even clearer. In this illustration, the vertical distances of the charging structure 10 , the frequency-selective structure 30 and the high frequency coupling structure 20 expanded to simplify the explanation. In the finished configured device according to this embodiment, the vertical distances between the structures are 10 . 20 and 30 a few millimeters to a few centimeters.

At the very bottom is a loading structure 10 arranged, which in the embodiment shown, a first coil 11 , a second coil 12 and a third coil 13 having. The spools 11 . 12 and 13 are each in stripline technology on or in an in 3 not shown printed circuit board formed. The outer coils 11 and 13 partially overlap each other with the inner coil 12 ; However, this structure is only to be understood as illustrative and not restrictive. The spools 11 . 12 and 13 the charging structure 10 are in turn with not shown further components of in 3 also not shown low-frequency charger 1 connected.

In the in 3 shown embodiment is above the charging structure 10 a frequency-selective structure 30 arranged. In the illustrated embodiment, the frequency-selective structure comprises a plurality of strip-shaped conductors 31 on. The individual strip-shaped conductors are on or in one 3 not shown printed circuit board formed and electrically isolated from each other. In the illustrated embodiment, n are in the longitudinal direction strip-shaped conductor 31 provided, in the transverse direction are m strip-shaped conductors 31 intended. The exact number of strip-shaped conductors 31 per row and per column depends on the desired wave reflection effect of the frequency-selective structure described below 30 together and is not limited to the illustrated embodiment.

Above the frequency-selective structure 30 is a high-frequency coupling structure 20 intended. The high-frequency coupling structure 20 has a first part 21 and a second part 22 on, which by means of a connecting part 23 are connected. The exact geometry of the high-frequency coupling structure 20 depends on the antenna characteristics of the mobile device to be connected 5 for example, during the design and design process. In the illustrated embodiment, the second part runs 22 for example, starting from the connecting part 23 for a certain length in the longitudinal direction forward, and then run back over a short transverse piece over the same length in the longitudinal direction again. The forward and rearward portions of the second portion are thus parallel to each other and spaced apart about the extent of the transverse portion. The first part 21 runs in the illustrated embodiment, starting from the connecting part 23 in the longitudinal direction in the backward direction of the first longitudinal direction portion of the first part, that is, opposite to that of the connecting part 23 opposite region of the second part 22 , then extends perpendicular to this direction in the opposite direction to the transverse direction piece of the second part 22 , and then proceeds longitudinally further forward to terminate in a short angled tail.

This geometry of the high-frequency coupling structure described by way of example 20 is adapted for the RF coupling of certain mobile device types. A high frequency coupling structure adapted to other types of mobile devices 20 may also require one of the deviating geometry described. The high-frequency coupling structure 20 can be independent of the frequency-selective structure 30 be adjusted. This adaptation of the high-frequency coupling structure 20 independent of the frequency-selective structure 30 can be done during the design or design process.

For example, the course of the first part 21 and / or the course of the second part 22 the high-frequency coupling structure 20 be adjusted. Alternatively or additionally, the width of the regions of the first part can also be used 21 and / or the width of the areas of the second part 22 be adjusted.

Although in the presentation in 3 not shown, are the high frequency coupling structure in the illustrated embodiment 20 and the frequency-selective structure 30 formed on different circuit board levels one and the same (not shown) printed circuit board; Here is the high frequency coupling structure 20 formed on the upper surface, and the frequency-selective structure 30 is formed on the lower surface.

As part of an adaptation of the high-frequency coupling structure 20 can be an existing design of a frequency-selective structure 30 be reused. Even if the high-frequency coupling structure 20 and the frequency-selective structure 30 may be formed on different circuit board levels of the same circuit board, during the design or design process, an adaptation of the geometry and / or the arrangement of the high-frequency coupling structure 20 be made, the arrangement and / or the geometry of the frequency-selective structure 30 is reused. Reusing may mean the design or design of an existing frequency-selective structure 30 in the design or design process.

Conventionally, a high-frequency coupling structure 20 and an associated groundplane are designed together and, if necessary, sharing them together. According to the described embodiments of the present invention, the designs may be separated at design or design stage. In addition, an existing structure, in particular an existing frequency-selective structure 30 to be reused in the design or draft stage.

In other words, even if such an adaptation is made during the design or design process, it is possible with the device according to the invention, a proven frequency-selective structure 30 reuse and with an altered radio frequency coupling structure 20 to combine. This distinguishes a device of the present invention, for example, from a conventional device, such as. B. from the DE 103 13 498 A1 is known. There is a modular interchangeability already during the design or design process is not provided.

It is in contrast to conventional devices, the z. B. from the DE 10 2010 027 620 A1 are known, according to the invention possible, the frequency-selective structure 30 and the high frequency coupling structure 20 independently design and combine as needed. While the conventional device of the DE 10 2010 027 620 A1 a joint design and providing a common formation of the planar extended antenna structure mentioned there and the directly associated eddy current-interrupting recesses in the planar structure, it is possible according to the invention, the frequency-selective structure 30 and the high frequency coupling structure 20 to design separately and form independently, for example on different circuit boards. This increases flexibility and reduces costs.

The spools 11 . 12 and 13 can be acted upon with a low-frequency signal, which is the inductive energy transfer to the mobile device 5 out 1 serves and is capable of, in the mobile device 5 to load the accumulator.

The individual strip-shaped ladder 31 the frequency-selective structure 30 are slightly spaced from each other, ie there is no galvanic connection between adjacent strip-shaped conductors 31 , The distance is chosen so that the LF signal with its compared to the RF signal very long wavelengths no or very small losses such. As eddy currents in the strip-shaped conductors 31 generated. At the same time, the distance between the individual strip-shaped conductors 31 small enough to be reflective with respect to the wavelength or wavelengths of the RF signal. The frequency-selective structure 30 lies between the high-frequency coupling structure 20 and the charging structure 10 and serves in the present embodiment as an electrical mirror plane for the high-frequency coupling structure 20 or their electromagnetic field effect.

The embodiment of the frequency selective structure discussed above 30 is for the in 3 shown high-frequency coupling structure 20 suitable. When using other geometries for the high-frequency coupling structure 20 but also a changed geometry of the frequency-selective structure 30 be desired. It can also be a modified geometry of the frequency-selective structure 30 be desirable if the geometry of the high-frequency coupling structure 20 is not changed, for example, the effect of the frequency-selective structure 30 to improve.

In 4 is a perspective view of a multi-level trained frequency-selective structure 30 a device according to another embodiment of the invention shown. In the 4 shown frequency-selective structure 30 has a relatively dense grid of meandering strands of strip lines, which are interconnected in the transverse direction at the ends. As in the embodiments described above, FIG 4 a circuit board on which the frequency-selective structure 30 is formed, not shown.

From the associated perspective exploded view in 5 is seen that again n × m strip-shaped conductors 32 are provided, which in the illustrated circuit board level 41 are galvanically separated from each other. In another circuit board level 42 , which is shown offset in perspective only for the purpose of better representability, are further longitudinal strip-shaped ladder 33 and further transverse strip-shaped conductors 34 educated. These strip-shaped ladder 33 . 34 are at their respective ends in the configured state by means of vias (not shown) with the respective ends of the strip-shaped conductors 32 connected, so that the total in 4 shown frequency-selective structure 30 is trained.

Also for the frequency-selective structure 30 according to the 4 and 5 is true that losses due to eddy currents and the like, which of a NF signal from the (in the 4 and 5 not shown) arranged below loading structure 10 originate, are largely prevented by the lattice-like shape. In other words, also the frequency-selective structure 30 according to the 4 and 5 is permeable to LF signals.

At the same time, the frequency-selective structure works 30 according to the 4 and 5 wave reflecting for RF signals from and / or to (in the 4 and 5 not shown) disposed above high-frequency coupling structure 20 , So for example, a planar inverted F antenna or the like.

It should be noted at this point that the above description parts relate to embodiments of the invention. However, the invention is not limited to the described embodiments, and the embodiments may be combined, or other embodiments may be devised without departing from the spirit of the invention. Changes, additions, modifications and the like are familiar to the expert.

LIST OF REFERENCE NUMBERS

1

Low-frequency charger

2

High-frequency signal coupling device

5

mobile device

6

charging Station

7

casing

8th

upper housing surface

10

charging structure

11

first coil of the charging structure

12

second coil of the charging structure

13

third coil of the charging structure

20

RF coupling structure

21

first part of the high-frequency coupling structure

22

second part of the high-frequency coupling structure

23

Connecting part of the high-frequency coupling structure

30

frequency-selective structure

31, 32, 33, 34

 strip-shaped conductor

41

first board level

42

second board level

Claims (9)

Device for wireless charging of a mobile device and the radio coupling thereof, which comprises a wireless low-frequency charging device and a high-frequency signal coupling device, wherein the high-frequency signal coupling device comprises a high-frequency coupling structure ( 20 ) for wireless coupling of a radio-frequency signal from or to the mobile radio device as well as a frequency-selective structure ( 30 ), wherein the frequency-selective structure ( 30 ) between the low frequency charger and the high frequency coupling structure ( 20 ), wherein the frequency-selective structure ( 30 ) is substantially transparent to the low frequency and substantially reflective to the high frequency, the frequency selective structure ( 30 ) at least in regions as a lattice structure, in particular as a lattice structure with galvanically separated strip-shaped conductors ( 31 ) is trained. Device according to claim 1, wherein the high-frequency signal coupling device is modular in such a way that the high-frequency coupling structure ( 20 ) and / or the frequency-selective structure ( 30 ) is designed exchangeable or are. Device according to claim 1 or 2, wherein the frequency-selective structure ( 30 ) acts for the high frequency at least approximately as a ground plane. Device according to one of the preceding claims, wherein the low-frequency charging device has a flat charging structure ( 10 ) for low-frequency energy transmission, in particular designed as a strip line flat coil structure. Device according to one of the preceding claims, wherein the frequency-selective structure ( 30 ) and the high-frequency coupling structure ( 20 ) are formed in or on one and the same circuit board, in particular in or on different circuit board levels one and the same circuit board. Device according to one of the preceding claims, wherein the frequency-selective structure ( 30 ) is formed in several levels, in particular in or on different circuit board levels one and the same circuit board. Device according to one of the preceding claims, wherein the high-frequency coupling structure ( 20 ) is connectable or connected to an electromagnetic radiator, in particular to an external antenna and preferably to an external vehicle antenna. Device according to one of the preceding claims, wherein the high-frequency coupling structure ( 20 ) is designed as an antenna structure, in particular as a planar inverted F antenna or as a line resonator structure. Vehicle-mounted charging and radio-coupling system for a mobile radio device, which has a device designed as a charging and coupling deposit according to one of claims 1 to 8, which can be arranged in the vehicle interior, wherein the radio-frequency coupling structure ( 20 ) has a connection to an external vehicle antenna.

Images