RU2781757C1 - Wireless connection for high-speed data transmission - Google Patents

Abstract

FIELD: communication.

SUBSTANCE: invention relates to a wireless system for high-speed data transmission. The system for wireless data transmission includes two antenna structures separated by a gap, while each antenna structure includes a printed circuit board, on which at least one antenna is located, while shielding elements are located around each of the mentioned at least one antenna, wherein each shielding element is connected to a load. The load is made on focused elements and topology elements of the printed circuit board.

EFFECT: increase in a speed of data transmission, increase in the reliability of a system for wireless data transmission, as well as reduction in its complexity and sizes.

14 cl, 4 dwg

Description

Technical field

The present invention relates to the field of radio engineering, in particular to a wireless system for high-speed data transmission.

State of the art

The growing volume of data transmission between various electronic devices at present demonstrates the need to develop systems for high-speed data transmission with compact size, simple architecture, low loss, high reliability and efficiency, low cost, etc. These requirements are of particular importance for wireless data transmission systems commonly used in various mobile and stationary electronic devices.

Such data transmission systems are used, among other things, in communication systems of new and promising data transmission standards, such as 5G (28 GHz), WiGig (60 GHz), Beyond 5G (60 GHz) and 6G (sub-terahertz range), wireless Long-distance wireless power transmission (LWPT) (24GHz), automotive radar systems (24GHz, 79GHz), etc.

It is worth noting that the circumstances mentioned above are typical not only for data transfer between electronic devices, but also for data transfer between different boards (components) within such devices.

To communicate for the purpose of transferring data in connections between different boards in electronic devices, two main approaches are currently used:

1) Galvanic connection.

Galvanic connections between connected components (for example, between printed circuit boards (PCB, Printed Circuit board)) are subject to damage due to vibrations, thermal expansion, mechanical stress, etc. In addition, due to inaccuracies in the assembly process or due to uneven thermal expansion of the connected components when heated, the contact pads of the connected components may be displaced relative to each other. This leads to a change in the parameters of the radio frequency (RF, Radio frequency) transition between the connected components and to an increase in losses, or to the complete inoperability of the resulting connection. Thus, known technologies exhibit a lack of reliability and accuracy, especially for applications in RF devices. At the same time, the desire to increase functionality (for example, data transfer rate) per unit volume and mass of equipment dictates an increase in the number of switching outputs, a decrease in the length of conductor routes and a decrease in the contact spacing, which again leads to an increase in the requirements for accuracy and reliability of contacts between components in radio frequency equipment. Thus, due to the disadvantages listed above, galvanic connections do not meet the increasing demands regarding the speed of data transfer between components.

2) Wireless connection.

A wireless data connection between components within a device can be implemented via radio frequency communication technology (eg, near-field communication (NFC, Near-field communication)), or via optical communication.

Existing NFC communication technologies are characterized by electromagnetic interference problems. To solve this problem, shielding is used, which significantly affects the parameters of the RF transition and leads to an increase in the geometric dimensions of the components, as well as an increase in noise in the data transmission channel. In addition, such a connection has a low bandwidth. It is also worth noting that the displacement of the NFC coils (transmitting and receiving) relative to each other leads to a change in the transition parameters and, accordingly, a mismatch and a decrease in data transmission efficiency.

The implementation of optical communication requires the alignment of the optical system and the presence of a direct line of sight between the transmitter and receiver. In addition, beam steering is required, which is not an easy task due to the small size of the receiver relative to the size of the device. Beam control is implemented through complex and high-precision mechanical systems, which affects the complexity of manufacturing such systems, as well as their reliability and cost.

In the prior art, a solution disclosed in US 2019/379426 A1 is known, which is a wireless data transmission system in which the transmitter and receiver are located on separate substrates or carrier elements that are located relative to each other so that during operation of the antenna pair, the transmitter /receiver are separated by such a distance that at the wavelengths of the carrier frequency of the transmitter, communication in the near field is obtained. However, in this solution, the antenna elements are integrated into integrated circuits, which are located on separate boards. Such integration of antenna elements into a microcircuit makes it impossible to quickly make changes to the design of the antenna so that it satisfies the required characteristics during mass production.

US 2017/250726 A1 discloses a wireless connector including a first communication device and a second communication device. The first communication device is configured to wirelessly transmit a modulated signal comprising a carrier signal modulated with a digital signal. The second communication device is configured to receive the modulated signal. The first and second communication devices are connected via at least one wired connection which carries a signal used to demodulate the modulated signal. Thus, the presented solution requires at least one galvanic connection to carry out demodulation. In addition, in this solution, the antenna elements are integrated into integrated circuits, which are located on separate boards.

US 8,041,227 B2 discloses a communication device having optical data transmission and data transmission via near field communication. The apparatus includes an optical transceiver circuit fabricated on an integrated circuit chip and configured to transmit and receive far field signals. The near field transceiver circuit is also fabricated on an integrated circuit chip and configured to transmit and receive near field electromagnetic signals. The control circuit is provided for selectively turning on the optical transceiver circuit and the near field transceiver circuit in response to an external control signal. However, the infrared (IR) data transmission system used in this solution has insufficient data transfer rate. In addition, for interaction, this solution requires an additional RF channel for pairing devices.

The solution disclosed in US 2009/289869 A1 is an antenna structure for electromagnetic coupling between a chip and an element outside the chip, including a first resonant structure located on or within the chip. The first resonant structure has a first resonant frequency. The antenna structure also includes a second resonant structure located on an element external to or within the chip. The second resonant structure is configured to have a second resonant frequency substantially the same as the first resonant frequency. The first resonant structure and the second resonant structure are mutually spaced at a near field distance from each other to form a coupled antenna structure that is configured to transmit electromagnetic energy between the chip and the external element. The electromagnetic energy has a selected wavelength in the wavelength range from microwaves to submillimeter waves. However, this solution has a narrow transmission bandwidth and does not support millimeter and sub-terahertz wavelengths.

Thus, the existing solutions have a number of disadvantages, the main ones being:

- low data transfer rate,

- low reliability,

- complex structure and/or

- high level of interference.

Therefore, there is currently a need for a compact, reliable, simple, and inexpensive wireless system capable of high-speed data transmission between electronic device components.

The essence of the invention

The present invention is directed to solving at least some of the above problems.

According to one aspect of the present invention, a wireless data transmission system is provided, including two antenna structures separated by a gap from each other, each antenna structure including a printed circuit board on which at least one antenna is located, while around each of the mentioned shielding elements are located on at least one antenna, each shielding element being connected to a load.

According to one embodiment, the antenna is an antenna array composed of identical antenna elements.

According to another embodiment of the system, the antenna array consists of four antenna elements arranged in a 2x2 matrix.

According to another embodiment of the system, the gap is an air gap.

According to another embodiment of the system, the air gap between the printed circuit boards is greater than half the wavelength of the signal at the minimum frequency of the operating band.

According to another embodiment of the system, the load is a microstrip or strip line.

According to another embodiment of the system, said line has a curvilinear shape.

According to another embodiment of the system, the line shape is selected from a spiral shape, a meander shape, or some combination thereof.

According to another embodiment of the system, the end of the microstrip line is shorted with a VIA (through plated through hole).

According to another embodiment of the system, said load is located on the inner layer of the printed circuit board.

According to another embodiment of the system, said loading is carried out on lumped elements and circuit board topology elements.

According to another embodiment of the system, the characteristics of the shielding elements match those of said antenna elements.

According to another embodiment of the system, the shielding elements are identical to said antenna elements.

According to another embodiment of the system, the antenna elements are patch antennas.

According to another embodiment, signal transmission to and from the antenna elements in the antenna structure is via a port, the antenna elements being connected to the port via a line acting as a signal splitter in the case of a transmitting antenna structure or a signal combiner function in the case of a receiving antenna structure, the line acting as a signal divider, provides equal and in-phase separation of the power of the electromagnetic signal transmitted to the antenna elements, and the line, which acts as a signal adder, provides in-phase addition of the power of the electromagnetic signals coming from the antenna elements.

The present invention can achieve a high data transmission rate while improving the reliability and efficiency of a wireless data transmission system with a simple architecture and compact size.

Brief description of the drawings

The invention is further explained by the description of preferred embodiments of the invention with reference to the accompanying drawings, in which:

Fig. 1 schematically depicts a section of one of the antenna structures of a wireless data transmission system in accordance with an exemplary embodiment of the present invention.

Fig. 2 schematically depicts an embodiment of a wireless data transmission system, wherein FIG. 2a is a plan view of one of the antenna structures of the wireless data transmission system, and FIG. 2b is a cross-sectional side view of a wireless data transmission system.

Fig. 3 shows various forms of load connected to the shielding element.

Fig. 4 shows an exemplary printed circuit board structure in which a load is located to be connected to the shielding element.

Detailed description

Embodiments are not limited to the embodiments described herein, other embodiments of the invention will become apparent to a person skilled in the art based on the information set forth in the description and knowledge of the prior art, without going beyond the essence and scope of this invention.

The wireless data transmission system consists of two antenna structures separated from each other by a gap and facing each other. The mentioned antenna structures carry out the functions of transmitting and receiving data, have the same design and can repeatedly change roles during operation, because the direction of data transfer in the system can be reversed.

In a preferred embodiment of the invention, the gap separating the antenna structures from each other is an air gap. In alternative embodiments, the gap may be filled with a dielectric layer or filled with a compound. Filling the gap with a dielectric layer, or potting it with a compound, can be advantageous in terms of providing mechanical strength and protection against the ingress of moisture and contaminants. In addition, a metamaterial can be placed in the gap, which improves and directs the propagation of the field. A combination of the mentioned options for filling the gap between the antenna structures is also possible.

Next, according to an exemplary embodiment, the structure of the signal transmission antenna structure in the wireless data transmission system will be described in more detail. However, the above description is also true for the receiving antenna structure, given the fact that the same antenna structure can transmit or receive a signal at different times.

As shown in FIG. 1, an antenna structure 1 according to an exemplary embodiment of the present invention includes a printed circuit board on which at least one antenna is located. In the exemplary embodiment in FIG. 1, the antenna is an antenna array 2, consisting of four antenna elements 3 arranged in a 2x2 matrix. The antenna elements 3 are patch antennas connected to a port 5 through which the signal to be transmitted is received via a line that functions as a signal divider 4 (or a signal adder in the case of reversed signal flow). Port 5, in turn, can be connected to an integrated circuit, such as a radio frequency integrated circuit (RFIC, Radio frequency integrated circuit), which sends a signal through the port to the antenna elements. The signal divider 4 provides an equal and in-phase division of the electromagnetic signal power between the antenna elements 3. Similarly, the signal combiner provides an in-phase addition of the electromagnetic signal power from the antenna elements. The electromagnetic field radiated from the antenna elements 3 is summed in phase and generates radiation with a high directivity. Most of the energy of the electromagnetic field is directed from the transmitting antenna structure to the receiving antenna structure, which allows for a high data rate and high bandwidth.

Patch antennas can be of any suitable shape, it is important that they are the same. This is necessary to ensure identical performance of the patch antennas.

It is worth noting that in alternative embodiments, the implementation of the antenna may contain a different number of antenna elements arranged in a different way. At the same time, the number and shape of the antenna elements described in the exemplary embodiment is preferable, because allows to provide a high directivity of the antenna array radiation pattern and low signal losses in the divider path. An increase in the number of antenna elements in the antenna array leads to an increase in losses in the divider path, while a decrease in the number of antenna elements in the antenna array worsens the directivity of the antenna array.

The implementation of the antenna structure on a printed circuit board can reduce the complexity of manufacturing. In addition, in the printed version, the design of the antenna can be easily changed by simply changing the design of the printed circuit board during the manufacturing process.

As shown in FIG. 1 and 2, shielding elements 6 (dummy elements) are located around the antenna array 2. The shielding elements 6 are made in the form of patch elements identical to the antenna elements 3 of the antenna array 2. This design of the shielding elements 6 leads to the fact that they have similar operating parameters with the antenna elements 3 of the antenna array 2, and therefore operate in the same frequency band. . It is worth noting that the shielding elements 6 prevent the emission of parasitic waves (interference signals) outward into the space between the printed circuit boards and the entry of interference signals from the outside (see Fig. 2a and 2b).

In an alternative embodiment, the shielding elements 6 may differ in shape from the antenna elements 3 of the antenna array 2. It must be ensured that the characteristics of said shielding elements 6, such as, for example, the operating frequency band, radiation pattern and gain, coincide with the characteristics of the antenna elements. 3 antenna array 2.

The electromagnetic field generated by the transmitting antenna array is divided into a useful signal and an interference signal. The useful signal is transmitted to the receiving antenna array and received by it. The receiving antenna array receives a clear signal, which enables high-speed data transmission. The interference signal enters the shielding elements 6, which receive and absorb said signal. External signals are also received by the shielding elements 6, which makes it possible to prevent interference signals from outside. The shielding elements 6 are located one array step away from the antenna elements 3. This allows for a very compact design of the antenna structure. Shielding elements 6 to ensure the absorption of interference signals are connected to loads 7 integrated into the printed circuit board 8.

In a preferred embodiment of the present invention, the data transmission system includes two antenna structures 1 (see Fig. 2b), separated from each other by an air gap, each antenna structure includes at least two antenna arrays 2 described above (see Fig. Fig. 2a), shielding elements 6 located around the mentioned antenna arrays 2, each shielding element 6 is connected to a load 7 integrated into the printed circuit board 8, and the air gap between the printed circuit boards can be more than half the signal wavelength with a minimum operating frequency frequency bands. In this case, it is possible to excite the modes of the resonator (Fabry-Perot resonator), formed by parallel conducting planes of printed circuit boards of antennas, at frequencies when the distance between the antennas is a multiple of half the wavelength (or close to it) in the medium between the boards, which leads to a decrease in the power of the received signal, but the shielding elements 6 effectively eliminate this effect of reducing the received power. In addition, protrusions or gaskets may be located in the gap, which are necessary for the assembly of the structure.

The load 7 (attenuator) connected to the shielding element 6, in the exemplary embodiment, is a microstrip line, the length of which ensures the absorption of the electromagnetic energy of the interference signal. To save space, the microstrip line may have a curved shape, such as a spiral shape, a meander shape (see Fig. 3a), or some combination of both (see Fig. 3b). Said microstrip line is located on the inner layer of the printed circuit board 8 (see Fig. 4), which prevents the interference signal from propagating into the outer space. The end of the microstrip line can be shorted (ie, connected to ground) with a VIA (through-hole). The volume occupied by the transmission line is surrounded by through VIAs to prevent leakage of energy into the PCB volume. The electromagnetic field propagating from the connection port of the microstrip line with the shielding element 6 receiving the interference signal is gradually absorbed in the microstrip line. Then it is reflected from the shorting VIA back to the port and is additionally absorbed. The reflected electromagnetic field reaching the port is too weak and cannot be radiated from the shielding element 6 to the antenna element 3. This provides low interference as well as high speed and data throughput in the useful signal.

As an alternative to a microstrip line, a strip line can be used. It should be noted that the load 7 for the shielding element 6 can be located both symmetrically with respect to the thickness of the printed circuit board 8 (i.e. in the middle of the thickness of the printed circuit board) and asymmetrically (i.e. with an offset relative to the middle of the thickness of the printed circuit board). Here, the location of the strip line depends on the thicknesses of the dielectrics that are used to manufacture the printed circuit board.

The location of the microstrip line on the inner layer of the printed circuit board during the production process avoids the use of complex and costly surface-mounted components (SMD, Surface mounted device) technology for mounting the load for the shielding element, but the load performed on SMD elements (or lumped elements) in a number cases, provides a more compact design of the device.

Thus, in an alternative embodiment, the load may be in the form of an electrical circuit of lumped elements, for example, resistors in which energy absorption occurs, and possibly circuit board layout elements, for example, quarter-wave line impedance transformers, electrical capacitances, etc. P.

The use of shielding elements helps to prevent the occurrence of the Fabry-Perot effect between antenna structures, which can have a negative impact on other data transmission channels between antenna structures. Also, antenna arrays with a high directivity factor reduce the fraction of power radiated into the space between the boards of the device, which further reduces the effect of excitation of the Fabry-Perot resonator mode. The load integrated into the printed circuit board and connected to the shielding element makes it possible to avoid the installation of additional components to absorb unwanted noise, which reduces the complexity and cost of production, and also increases the reliability of the proposed solution.

It should be noted that in the present invention, it is permissible to shift the antenna structures (transmitting and receiving) relative to each other by a distance of the order of a wavelength in the operating frequency range. This shift does not affect the quality of the connection. This tolerance is more than sufficient for device assembly. It is also possible to shift the antennas in the transverse direction, both small, due to the accuracy of the assembly, and constructive, associated with design requirements. In this case, if the antennas are located in the far radiation zone, then it is possible to use a power divider and adder that form radiation in the direction of the second antenna. With a small distance between the antennas, the transmission efficiency is determined by the intersection of the antenna apertures.

The present invention enables ultra-wideband (greater than 500 MHz bandwidth) and high-speed wireless communication between printed circuit boards/chips with low noise and low loss.

Thus, the present invention enables high-speed data communication performed with a compact, reliable, simple and inexpensive data communication system.

The present invention can find application in 5G (28 GHz), WiGig (60 GHz), Beyond 5G (60 GHz) and 6G (sub-terahertz) wireless communication systems, near range (60 GHz, NFC) communication systems, in wireless data transmission between different modules in modular devices, between components in electronic devices, etc. In addition, the present invention can be used in systems of circular (360 ⁰ ) view without mechanical rotation.

It should be understood that although terms such as "first", "second", "third" and the like may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components , regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section may be referred to as a second element, component, region, layer, or section without departing from the scope of the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the respective listed positions. Elements mentioned in the singular do not exclude the plurality of elements, unless otherwise specified.

The functionality of an element specified in the description or claims as a single element may be practiced by means of several components of the device, and conversely, the functionality of elements indicated in the description or claims as several separate elements may be practiced by means of a single component.

Embodiments of the present invention are not limited to the embodiments described herein. Specialist in the field of technology on the basis of the information set forth in the description and knowledge of the prior art will become apparent and other embodiments of the invention that do not go beyond the essence and scope of this invention.

Elements mentioned in the singular do not exclude the plurality of elements, unless otherwise specified.

A person skilled in the art should be clear that the essence of the invention is not limited to a particular software or hardware implementation, and therefore for the implementation of the invention can be used in any software and hardware known in the prior art. Thus, hardware may be implemented in one or more ASICs, digital signal processors, digital signal processors, programmable logic devices, user programmable gate arrays, processors, controllers, microcontrollers, microprocessors, electronic devices, other electronic modules configured to perform the functions described in this document, a computer, or a combination of the above.

While exemplary embodiments have been described and shown in the accompanying drawings, it should be understood that such embodiments are illustrative only and are not intended to limit the broader invention, and that the invention should not be limited to the particular arrangements and structures shown and described, since various other modifications may be apparent to those skilled in the art.

Features mentioned in various dependent claims, as well as embodiments disclosed in various parts of the description, can be combined to achieve beneficial effects, even if the possibility of such a combination is not explicitly disclosed.

Claims (14)

1. A wireless data transmission system that includes two antenna structures separated by a gap from each other, with each antenna structure including a printed circuit board on which at least one antenna is located, while around each of said at least one antenna shielding elements are located, each shielding element is connected to a load, and said load is made on concentrated elements and elements of the printed circuit board topology. 2. The wireless data transmission system of claim 1, wherein the antenna is an antenna array composed of identical antenna elements. 3. The wireless data transmission system of claim 2, wherein the antenna array consists of four antenna elements arranged in a 2x2 array. 4. The wireless communication system of claim 1, wherein the gap is an air gap. 5. The wireless communication system of claim 4, wherein the air gap between the printed circuit boards is greater than half the wavelength of the signal at the minimum frequency of the operating band. 6. The wireless communication system of claim 1, wherein the load is a microstrip or stripline. 7. The wireless communication system of claim 6, wherein said line has a curved shape. 8. The wireless communication system of claim 7, wherein the line shape is selected from a spiral shape, a meander shape, or some combination thereof. 9. The wireless data transmission system of claim 6, wherein the end of the microstrip line is connected to ground via a VIA - plated through hole. 10. The wireless communication system of claim 1, wherein said load is located on an inner layer of a printed circuit board. 11. The wireless data transmission system of claim 2, wherein the characteristics of the shielding elements match those of said antenna elements. 12. The wireless communication system of claim 11, wherein the shielding elements are identical to said antenna elements. 13. The wireless communication system of claim 2, wherein the antenna elements are patch antennas. 14. The wireless data transmission system of claim 2, wherein signal transmission to and from the antenna elements in the antenna structure is via a port, the antenna elements being connected to the port via a line acting as a signal splitter in the case of a transmitting antenna structure or a signal combiner function. in the case of a receiving antenna structure, wherein the line acting as a signal divider ensures equal and in-phase separation of the power of the electromagnetic signal transmitted to the antenna elements, and the line acting as a signal adder provides in-phase addition of the power of the electromagnetic signals coming from the antenna elements.

Images