Human body communication device, system and control method

Abstract

The invention discloses a human body communication device and system and a control method. The human body communication device comprises a human body communication chip, a first electrode, a second electrode and a dielectric medium, the human body communication chip is electrically connected with the first electrode and the second electrode. The dielectric medium is arranged on the side, away from the second electrode, of the first electrode. The first electrode is not electrically connected with the human body, and the second electrode is electrically connected with the human body.

Description

Technical Field

[0001] The present application relates to the field of human body communication, and in particular to a human body communication device, system and control method. Background Art

[0002] The human body communication device includes an electrode electrically connected to the human body and an electrode not electrically connected to the human body, and human body communication is performed through these two electrodes. Generally, the larger the area of ​​the electrode not electrically connected to the human body, the larger the equivalent capacitance between the electrode and the ground terminal, and the better the human body communication performance. However, for some human body communication devices (such as mobile phones), the internal space is limited, which limits the increase in the area of ​​the electrode, so the human body communication performance is poor. Summary of the invention

[0003] Embodiments of the present application provide a human body communication device, system and control method for increasing the equivalent capacitance between an electrode that is not electrically connected to a human body and a ground terminal in a human body communication device, thereby improving human body communication performance.

[0004] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0005] In a first aspect, a human body communication device is provided, comprising: a human body communication chip, a first electrode, a second electrode, and a dielectric; the human body communication chip is electrically connected to the first electrode and the second electrode, respectively, and the dielectric is arranged on a side of the first electrode away from the second electrode; the first electrode is not electrically connected to the human body, and the second electrode is used to be electrically connected to the human body.

[0006] The human body communication device provided in an embodiment of the present application includes a first electrode that is not electrically connected to the human body and a second electrode that is electrically connected to the human body. By adding a dielectric on a side of the first electrode away from the second electrode, the equivalent capacitance between the first electrode and the ground terminal is increased, thereby improving the human body communication performance.

[0007] In a possible implementation, it also includes a processor and a multi-open switch. There are multiple first electrodes, and the multiple first electrodes are electrically connected to the human body communication chip in parallel through the multi-open switch. The human body communication chip or the processor is used to control the multi-open switch to connect the human body communication chip to at least one of the multiple first electrodes. Multiple first electrodes that are not electrically connected to the human body are electrically connected to the human body communication chip through the multi-open switch. The human body communication chip or the processor can control the multi-open switch to disconnect the first electrode among the multiple first electrodes that is greatly affected by being close to the human body, so as to avoid the first electrode from affecting other first electrodes, thereby avoiding the human body communication performance from being reduced when the human body is close to the electrode that is not electrically connected to the human body in the human body communication device.

[0008] In a possible implementation, the human body communication chip or processor is specifically used to: detect abnormal human body communication; control the multi-open switch to disconnect the electrical connection between the human body communication chip and each first electrode respectively, wherein when the electrical connection between the human body communication chip and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip and the target first electrode is kept disconnected, otherwise the electrical connection between the human body communication chip and the target first electrode is restored. This implementation discloses how to determine the first electrode that is greatly affected by the human body and disconnect the electrical connection between the human body communication chip and the first electrode.

[0009] In a possible implementation, the human body communication abnormality includes: the human body communication is disconnected; or the average power of the AC signal received by the human body communication chip in the first time period is the first power, and the average power of the AC signal received by the human body communication chip in the second time period is the second power, and the first power minus the second power is greater than the first threshold. That is, the AC signal cannot be received by the human body communication chip, or the signal attenuation of the human body communication increases by a certain amplitude.

[0010] In a possible implementation, the improvement of human body communication includes: the human body communication is restored; or, the average power of the AC signal received by the human body communication chip in the third time period is the third power, and the average power of the AC signal received by the human body communication chip in the fourth time period is the fourth power, and the fourth power minus the third power is greater than the second threshold. That is, the AC signal is received again by the human body communication chip, or the signal attenuation of the human body communication is reduced by a certain amplitude.

[0011] In a possible implementation, the plurality of first electrodes are located in different areas of the human body communication device, so as to avoid the plurality of first electrodes being affected by the human body at the same time, thereby reducing the human body communication performance.

[0012] In a possible implementation, the dielectric is a back shell of the human body communication device, and the first electrode is disposed on the inner side of the back shell. For a human body communication device such as a mobile phone, the back shell is inherent, and there is no need to add an additional dielectric, thereby saving internal space. Moreover, compared with directly exposing the first electrode to the outside and contacting the human body, disposing the first electrode on the inner side of the back shell can prevent huge transmission losses.

[0013] In a possible implementation, the dielectric is one of the following materials: alumina ceramics, zirconium oxide ceramics, polytetrafluoroethylene, polyimide. The present application does not limit the above high dielectric constant materials.

[0014] In a possible implementation, the dielectric constant of the dielectric is greater than 4. The present application does not limit the dielectric constant of the high dielectric constant material.

[0015] In a possible implementation, the area of ​​the dielectric is larger than the area of ​​the first electrode. Within a certain range, the larger the area of ​​the dielectric is, the larger the equivalent capacitance between the first electrode and the ground terminal is.

[0016] In a possible implementation, the first electrode is an antenna branch, or the first electrode is a metal component of a camera module. For a human body communication device such as a mobile phone, the antenna branch or camera module is inherent, so no additional metal components are added, saving internal space and material costs.

[0017] In a possible implementation, the second electrode is a metal middle frame of the human body communication device. For human body communication devices such as mobile phones, the metal middle frame is inherent, and no additional metal parts need to be added, thus saving internal space.

[0018] In a second aspect, a human body communication device is provided, including: a processor, a human body communication chip, a multi-open switch, a second electrode and a plurality of first electrodes; the plurality of first electrodes are electrically connected in parallel to the human body communication chip through the multi-open switch, the human body communication chip is also electrically connected to the second electrode, the plurality of first electrodes are not electrically connected to the human body, and the second electrode is used to be electrically connected to the human body; the human body communication chip or the processor is used to control the multi-open switch to connect the human body communication chip to at least one of the plurality of first electrodes.

[0019] In the human body communication device provided in the embodiment of the present application, multiple first electrodes that are not electrically connected to the human body are electrically connected to the human body communication chip through a multi-open switch. The human body communication chip or processor can control the multi-open switch to disconnect the first electrode among the multiple first electrodes that is greatly affected due to being close to the human body, thereby avoiding the first electrode from affecting other first electrodes, thereby avoiding the human body communication performance from being reduced when the human body is close to the electrode that is not electrically connected to the human body in the human body communication device.

[0020] In a possible implementation, the human body communication chip or processor is specifically used to: detect abnormal human body communication; control the multi-open switch to disconnect the electrical connection between the human body communication chip and each first electrode respectively, wherein when the electrical connection between the human body communication chip and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip and the target first electrode is kept disconnected, otherwise the electrical connection between the human body communication chip and the target first electrode is restored; the first electrode is not electrically connected to the human body. This implementation discloses how to determine the first electrode that is greatly affected by the human body and disconnect the electrical connection between the human body communication chip and the first electrode.

[0021] In one possible implementation, human body communication abnormalities include: human body communication disconnection; or, the average power of the AC signal received by the human body communication chip in a first time period is a first power, and the average power of the AC signal received by the human body communication chip in a subsequent second time period is a second power, and the first power minus the second power is greater than a first threshold.

[0022] In one possible implementation, the improvement of human body communication includes: the human body communication connection is restored; or, the average power of the AC signal received by the human body communication chip in a third time period is a third power, and the average power of the AC signal received by the human body communication chip in a subsequent fourth time period is a fourth power, and the fourth power minus the third power is greater than the second threshold.

[0023] In a possible implementation, the plurality of first electrodes are located in different areas of the human body communication device, so as to avoid the plurality of first electrodes being affected by the human body at the same time, thereby reducing the human body communication performance.

[0024] In a possible implementation, a dielectric is disposed on one side of the first electrode away from the second electrode (e.g., the surface is covered) to increase the equivalent capacitance between the first electrode and the ground terminal. The dielectric is made of a high dielectric constant material, and the high dielectric constant material covered on the surface of the first electrode can further increase the equivalent capacitance between the first electrode and the ground terminal, thereby improving the human body communication performance of the human body communication device.

[0025] In a possible implementation, the dielectric is a back shell of the human body communication device, and the first electrode is disposed on the inner side of the back shell. For a human body communication device such as a mobile phone, the back shell is inherent, and there is no need to add an additional dielectric, thereby saving internal space. Moreover, compared with directly exposing the first electrode to the outside and contacting the human body, disposing the first electrode on the inner side of the back shell can prevent huge transmission losses.

[0026] In a possible implementation, the dielectric is one of the following materials: alumina ceramics, zirconium oxide ceramics, polytetrafluoroethylene, polyimide. The present application does not limit the above high dielectric constant materials.

[0027] In a possible implementation, the dielectric constant of the dielectric is greater than 4. The present application does not limit the dielectric constant of the high dielectric constant material.

[0028] In a possible implementation, the area of ​​the dielectric is larger than the area of ​​the first electrode. Within a certain range, the larger the area of ​​the dielectric is, the larger the equivalent capacitance between the first electrode and the ground terminal is.

[0029] In a possible implementation, the first electrode is an antenna branch, or the first electrode is a metal component of a camera module. For a human body communication device such as a mobile phone, the antenna branch or camera module is inherent, so no additional metal components are added, saving internal space and material costs.

[0030] In a possible implementation, the second electrode is a metal middle frame of the human body communication device. For human body communication devices such as mobile phones, the metal middle frame is inherent, and no additional metal parts need to be added, thus saving internal space.

[0031] In a third aspect, a human body communication system is provided, comprising a first human body communication device and a second human body communication device, wherein the first human body communication device and the second human body communication device perform human body communication through a human body, and the first human body communication device or the second human body communication device is the human body communication device described in the first aspect and any embodiment thereof.

[0032] In a fourth aspect, a control method for a human body communication device is provided, which is applied to the human body communication device described in the first aspect or the second aspect and any embodiment thereof, the method comprising: detecting abnormal human body communication; controlling a multi-open switch to respectively disconnect the electrical connection between the human body communication chip and each first electrode, wherein, when the electrical connection between the human body communication chip and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip and the target first electrode is kept disconnected, otherwise the electrical connection between the human body communication chip and the target first electrode is restored; the first electrode is not electrically connected to the human body.

[0033] In one possible implementation, human body communication abnormalities include: human body communication disconnection; or, the average power of the AC signal received by the human body communication chip in a first time period is a first power, and the average power of the AC signal received by the human body communication chip in a subsequent second time period is a second power, and the first power minus the second power is greater than a first threshold.

[0034] In one possible implementation, the improvement of human body communication includes: the human body communication connection is restored; or, the average power of the AC signal received by the human body communication chip in a third time period is a third power, and the average power of the AC signal received by the human body communication chip in a subsequent fourth time period is a fourth power, and the fourth power minus the third power is greater than the second threshold.

[0035] In a fifth aspect, a computer-readable storage medium is provided, comprising instructions, which, when executed on a human body communication device, enable the human body communication device to execute the method described in the fourth aspect and any one of its embodiments.

[0036] In a sixth aspect, a computer program product comprising instructions is provided. When the instructions are executed on the above-mentioned human body communication device, the human body communication device executes the method described in the fourth aspect and any one of its embodiments.

[0037] The technical effects of the third to sixth aspects refer to the technical effects of the first or second aspect and any embodiment thereof, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a human body communication scenario provided in an embodiment of the present application;

[0039] Figure 2 A schematic diagram of an equivalent circuit of a single electrode provided in an embodiment of the present application;

[0040] Figure 3 A schematic diagram of an equivalent circuit of two electrodes provided in an embodiment of the present application;

[0041] Figure 4 A schematic diagram of another equivalent circuit of two electrodes provided in an embodiment of the present application;

[0042] Figure 5 A schematic diagram of an equivalent circuit of a human body and electrodes provided in an embodiment of the present application;

[0043] Figure 6 A schematic diagram of an equivalent circuit and signal attenuation when human body communication cannot be performed between two groups of electrodes provided in an embodiment of the present application;

[0044] Figure 7 A schematic diagram of an equivalent circuit and signal attenuation when two groups of electrodes can communicate with each other in the human body provided in an embodiment of the present application;

[0045] Figure 8 A schematic diagram of the effect of increasing dielectric on human communication performance and signal attenuation provided in an embodiment of the present application;

[0046] Fig. 9 A schematic diagram showing that increasing the dielectric is equivalent to increasing the electrode area provided in an embodiment of the present application;

[0047] Fig.10 A schematic diagram of a human body communication system provided in an embodiment of the present application;

[0048] Fig.11 A schematic diagram of the reason for limiting the size of electrodes in a human body communication device provided in an embodiment of the present application;

[0049] Fig.12 A schematic diagram of a human body communication device provided in an embodiment of the present application;

[0050] Fig.13 A schematic diagram of a human body communication device provided in an embodiment of the present application when it is a mobile phone;

[0051] Fig.14 A schematic diagram of signal attenuation comparison before and after adding dielectric provided in an embodiment of the present application;

[0052] Fig.15 A schematic diagram of adding a multi-open switch to connect multiple first electrodes in parallel provided in an embodiment of the present application;

[0053] Fig.16 A schematic diagram of a signal attenuation comparison before and after a human body approaches a single electrode provided in an embodiment of the present application;

[0054] Fig.17 A schematic diagram of another human body communication device provided in an embodiment of the present application;

[0055] Fig.18 A schematic diagram of another human body communication device provided in an embodiment of the present application;

[0056] Fig.19 A schematic diagram of a flow chart of a control method of a human body communication device provided in an embodiment of the present application;

[0057] Fig. 20 A schematic diagram of signal attenuation comparison before and after disconnecting the affected first electrode provided in an embodiment of the present application. DETAILED DESCRIPTION

[0058] First, some concepts involved in this application are described.

[0059] The terms "first", "second", etc. involved in the embodiments of the present application are only used to distinguish features of the same type and cannot be understood as indicating relative importance, quantity, order, etc.

[0060] The terms "exemplary" or "for example" and the like in the embodiments of the present application are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the terms "exemplary" or "for example" is intended to present the related concepts in a specific way.

[0061] The terms "coupling" and "connection" involved in the embodiments of the present application should be understood in a broad sense. For example, they may refer to a direct physical connection, or an indirect connection achieved through electronic devices, such as a connection achieved through resistors, inductors, capacitors or other electronic devices.

[0062] Human body communication: Compared with traditional Bluetooth (BT), wireless fidelity (Wi-Fi), and radio frequency (RF), human body communication is less affected by the electromagnetic environment because it transmits signals through the human body. It has the advantages of high speed, low power consumption, high confidentiality, and low damage to the human body. Human body communication can be applied to safe driving, human health care, smart home, data communication between a mobile phone held by a single person and a smart watch, and data exchange between terminals held by two people shaking hands. For example, Figure 1 As shown, the user holds a mobile phone 01 in one hand and wears a smart watch 02 in the other hand. The smart watch 02 can send the collected heart rate, blood pressure and other information to the mobile phone 01 through human body communication, and the mobile phone 01 can also send the time, weather and other information to the smart watch 02 through human body communication.

[0063] Human body communication includes two modes: capacitive human body communication and current human body communication. This application takes capacitive human body communication as an example for explanation. In order to understand the principle of capacitive human body communication, it is first necessary to understand that there are equivalent capacitances between electrodes, between electrodes and ground terminals, and between electrodes and the human body.

[0064] The following discusses the equivalent circuit of a single electrode in vacuum. Figure 2 As shown, electrode M1 is a charged sphere with a radius of r0 and a charge of Q. The potential difference between electrode M1 and the ground terminal GND (theoretically, the ground terminal GND is considered to be infinitely far away ∞) is k is the coefficient, E is the electric potential. Then the equivalent circuit of a single electrode M1 in vacuum is equivalent to the capacitor C being electrically connected to the ground terminal GND. S is the surface area of ​​the charged sphere, and ε0 is the dielectric constant. That is, the equivalent capacitance C of a single electrode in a vacuum is Directly proportional.

[0065] Next, we discuss the equivalent circuit of two electrodes in a vacuum. In the two scenarios where the distance between the two electrodes is far or close, the equivalent circuit of the two electrodes is different.

[0066] like Figure 3 As shown, due to the limited range of the electric field of the electrode, when the distance between two electrodes (such as electrode M1 and electrode N1) is far, the influence of the electric fields of the two electrodes on each other can be ignored. Therefore, it can be considered that there is a ground terminal GND between the two electrodes, and the equivalent circuit of the two electrodes is a capacitor C1 and a capacitor C2 connected in series, where capacitor C1 is the equivalent capacitance between electrode M1 and the ground terminal GND, and capacitor C2 is the equivalent capacitance between electrode N1 and the ground terminal GND. The equivalent capacitance C between electrode M1 and electrode N1 in vacuum satisfies: Furthermore, when the distance between electrode M1 and electrode N1 is very far, if the distance between the two electrodes is increased, the capacitance C will not continue to change. For example, assuming that both electrodes are charged spheres with a diameter of 5 cm, when the distance between the two electrodes is 0.1 m, the equivalent capacitance C between the two electrodes is 1.87 pF; when the distance between the two electrodes is 0.2 m, the equivalent capacitance C between the two electrodes is 1.59 pF; when the distance between the two electrodes is greater than or equal to 1 m, the equivalent capacitance C between the two electrodes is approximately 1.44 pF.

[0067] like Figure 4-Figure 5 As shown, when the distance between two electrodes (e.g., electrode M1 and electrode M2) is relatively close, the equivalent circuit of the two electrodes is that capacitor C2 and capacitor C3 are connected in series and then connected in parallel with capacitor C1 to the ground, wherein capacitor C1 is the equivalent capacitance between electrode M1 and the ground terminal GND, capacitor C2 is the equivalent capacitance between electrode M1 and electrode M2, and capacitor C3 is the equivalent capacitance between electrode M2 ​​and the ground terminal GND. Figure 4 In B relative to Figure 4 As shown in A, if the surface area of ​​electrode M2 ​​is increased, capacitance C1 will decrease, and the equivalent capacitance C2 between electrode M2 ​​and electrode M1 will increase. Figure 5 In B relative to Figure 5 As shown in A, if the distance between electrode M2 ​​and electrode M1 is reduced, capacitance C1 will decrease and capacitance C2 will increase. It should be noted that the human body is also a conductor. When the human body replaces electrode M2, or when the human body contacts electrode M2 ​​and is equivalent to a conductor, the human body and electrode M2 ​​are equivalent.

[0068] exist Figure 3-Figure 5 As shown in the basis, Figure 6 As shown, it is assumed that there are two groups of electrodes, each group of electrodes includes two electrodes that are close to each other, for example, the first group of electrodes includes electrode M1 and electrode M2, and the second group of electrodes includes electrode N1 and electrode N2, and the relationship between electrode M1 and electrode M2 ​​and the relationship between electrode N1 and electrode N2 are similar. Figure 4-Figure 5 The relationship between the electrode M1 and the electrode M2; the relationship between the electrode M1 and the electrode N1 and the relationship between the electrode M2 ​​and the electrode N2 are similar. Figure 3 The relationship between the electrodes M1 and N1 is similar to Figure 4-Figure 5 The relationship between the electrodes M1 and M2. Neither of these two sets of electrodes is electrically connected to the human body, so no matter how far the distance between the two sets of electrodes is ( Figure 6 In the middle, A means the distance between the two groups of electrodes is relatively close. Figure 6In the figure, B means that the distance between the two groups of electrodes is far), and the two groups of electrodes cannot communicate with each other. That is, if an AC signal is applied between the first group of electrodes (electrode M1 and electrode M2), it is difficult to detect the AC signal between the second group of electrodes (electrode N1 and electrode N2), or if an AC signal is applied between the second group of electrodes (electrode N1 and electrode N2), it is difficult to detect the AC signal between the first group of electrodes (electrode M1 and electrode M2). The reason is: For example, Figure 6 As shown in C, after simulation, when the frequency of the AC signal is 15MHz, when both sets of electrodes are not electrically connected to the human body, the signal attenuation of the AC signal transmitted between the two sets of electrodes is -130db, which exceeds the detection capability of general hardware for AC signals.

[0069] It should be noted that in Figure 6 In the figure, capacitor C1 is the equivalent capacitance between electrode M1 and the ground terminal GND, capacitor C2 is the equivalent capacitance between electrode M1 and electrode M2, capacitor C3 is the equivalent capacitance between electrode M2 ​​and the ground terminal GND, capacitor C4 is the equivalent capacitance between electrode N1 and the ground terminal GND, capacitor C5 is the equivalent capacitance between electrode N1 and electrode N2, capacitor C6 is the equivalent capacitance between electrode N2 and the ground terminal GND, capacitor C7 is the equivalent capacitance between electrode M1 and electrode N1, and capacitor C8 is the equivalent capacitance between electrode M2 ​​and electrode N2.

[0070] However, if one electrode from each of the two sets of electrodes is electrically connected to the human body, and the other two electrodes are not electrically connected to the human body, communication between the two sets of electrodes can be achieved. Figure 7 As shown in A, it is assumed that electrodes M1 and N1 are electrodes not electrically connected to the human body, electrodes M2 and N2 are electrodes electrically connected to the human body, capacitor C9 is the equivalent capacitance between electrode M2 ​​and the human body, capacitor C10 is the equivalent capacitance between electrode N2 and the human body, capacitor C11 is the equivalent capacitance between electrode M1 and the human body, capacitor C12 is the equivalent capacitance between electrode N1 and the human body, and capacitor C13 is the equivalent capacitance between the human body and the ground terminal GND. Capacitors C1-C6 refer to Figure 6 As described in the Figure 7 As shown in B, after simulation, when the frequency of the AC signal is 15MHz, when one electrode is taken from each of the two groups of electrodes and electrically connected to the human body, the signal attenuation of the AC signal transmitted between the two groups of electrodes is -45db, which means that the signal attenuation of 85db can be reduced. The detection capability of general hardware for AC signals can meet this requirement, so AC signals can be transmitted between the two groups of electrodes. This is the basic principle of human body communication.

[0071] And, after simulation, Figure 7The larger the capacitance values ​​of capacitors C1, C4, C9, and C10, the better the human body communication performance. For example, the signal attenuation of human body communication is small and it is not easy to disconnect. The smaller the capacitance values ​​of capacitors C1, C4, C9, and C10, the worse the human body communication performance. For example, the signal attenuation of human body communication is large, and even causes the human body communication to disconnect. Figure 5 In the analysis of B, since electrodes M2 and N2 are electrically connected to the human body, capacitors C9 and C10 are inherently large. However, electrodes M1 and N1 are not electrically connected to the human body, so capacitors C1 and C4 are inherently small, becoming a key factor restricting the human body communication performance.

[0072] Since the capacitance value of a capacitor is related to the area of ​​the electrode and the dielectric constant of the dielectric coupled to the electrode, the larger the area of ​​the electrode, or the larger the dielectric constant of the dielectric coupled to the electrode, the larger the capacitance value of the capacitor. Therefore, when designing a human body communication device, the equivalent capacitance C1 between the electrode N1 and the ground terminal and the equivalent capacitance C4 between the electrode N1 and the ground terminal will be increased as much as possible. Specifically, the following three methods may be included: the area of ​​the electrode M1 and the electrode N1 may be increased; or, a dielectric may be added to the side of the electrode M1 away from the electrode M2, and a dielectric may be added to the side of the electrode N1 away from the electrode N2; or, the dielectric constant of the above dielectric may be increased (for example, using a high dielectric constant material).

[0073] like Figure 8 As shown in A, adding dielectric E1 to the side of electrode M1 away from electrode M2 ​​is equivalent to Figure 7 On the basis of , a dielectric is added between the electrode M1 and the ground terminal GND to increase the equivalent capacitance C1 between the electrode M1 and the ground terminal GND. The larger the dielectric constant of the dielectric E1, the larger the equivalent capacitance C1 between the electrode M1 and the ground terminal GND, and the better the human body communication performance. Similarly, adding a dielectric E2 to the side of the electrode N1 away from the electrode N2 is equivalent to Figure 7 On the basis of, a dielectric is added between the electrode N1 and the ground terminal GND to increase the equivalent capacitance C4 between the electrode N1 and the ground terminal GND. The larger the dielectric constant of the dielectric E2, the larger the equivalent capacitance C4 between the electrode N1 and the ground terminal GND, and the better the human body communication performance. Figure 8 As shown in Figure B, after simulation, if a dielectric is added to the side of electrode M1 away from electrode M2, and a dielectric is added to the side of electrode N1 away from electrode N2, then when the frequency of the AC signal is 15MHz, the signal attenuation of the AC signal transmitted between the two groups of electrodes after adding the dielectric is -35db, which is -45db when the dielectric is not added (corresponding to Figure 7 B), further reducing the signal attenuation by 10db. Fig. 9As shown, after simulation, the equivalent capacitance of a single 4mm*4mm electrode is 0.28pF. If a dielectric with a dielectric constant of 4 is added to the electrode, the equivalent capacitance of the electrode can be changed to 0.53pF (approximately increased by 1 times), which is equivalent to the area of ​​the electrode being 7mm*10mm, that is, the area of ​​the electrode is increased by 4.3 times.

[0074] like Fig.10 As shown, based on the above-mentioned human body communication principle, an embodiment of the present application provides a human body communication system, including: a first human body communication device 11 and a second human body communication device 12. After the first human body communication device 11 and the second human body communication device 12 are electrically connected to the human body, the first human body communication device 11 and the second human body communication device 12 can perform two-way human body communication through the human body. The first human body communication device 11 and the second human body communication device 12 can be electronic devices capable of human body communication. For example, the first human body communication device 11 can be a mobile phone, and the second human body communication device 12 can be a smart watch, a virtual reality device, etc.

[0075] The first human body communication device 11 includes a first human body communication chip 111 and a first processor 112, an electrode M1 and an electrode M2 ​​electrically connected to the first human body communication chip 111. The second human body communication device 12 includes a second human body communication chip 121 and a second processor 122, an electrode N1 and an electrode N2 electrically connected to the second human body communication chip 121. Electrode M1 and electrode N1 are electrodes that are not electrically connected to the human body (hereinafter referred to as the first electrode), and electrode M2 ​​and electrode N2 are electrodes electrically connected to the human body (hereinafter referred to as the second electrode). For electrode M1, electrode M2, electrode N1, and electrode N2, reference can be made to the above description. It should be noted that, in the embodiment of the present application, the electrical connection between the electrode and the human body includes not only direct electrical connection, but also electrical connection through a conductor. For the same human body communication device, the human body communication chip can obtain data from the processor and transmit an AC signal corresponding to the data through two electrically connected electrodes, or the human body communication chip can receive an AC signal through two electrically connected electrodes and send data corresponding to the AC signal to the processor.

[0076] like Figure 7 As described in , in order to improve the performance of human body communication, when designing a human body communication device, the equivalent capacitance C1 between the electrode N1 and the ground terminal and the equivalent capacitance C4 between the electrode N1 and the ground terminal will be increased as much as possible, specifically including three methods. For electronic devices such as mobile phones and smart watches, the internal storage space is very limited, and there are many metal parts. If the distance between metal parts is too close, the coupling capacitance between the metal parts will increase, which has a greater impact on the performance of human body communication. Therefore, the area of ​​the electrode is limited. For example, Fig.11As shown, taking the human body communication device as a mobile phone as an example, the wireless charging coil 22, the antenna 23 and the metal parts in the camera module 21 will occupy a large area, making it difficult to increase the area of ​​the electrode used for human body communication, thereby affecting the performance of human body communication. Therefore, the present application can increase the equivalent capacitance C1 between the electrode M1 and the ground terminal by adding a dielectric (especially, using a high dielectric constant material) to the side of the electrode M1 away from the electrode M2, or increase the equivalent capacitance C4 between the electrode N1 and the ground terminal by adding a dielectric (especially, using a high dielectric constant material) to the side of the electrode N1 away from the electrode N2, thereby improving the performance of the human body communication device in human body communication.

[0077] like Fig.12 As shown, the human body communication device 13 (corresponding to the first human body communication device 11 or the second human body communication device 12 described above) provided in the embodiment of the present application includes: a human body communication chip 1301 (corresponding to the first human body communication chip 111 or the second human body communication chip 121 described above), a processor 1302 (corresponding to the first processor 112 or the second processor 122 described above), a first electrode 1303 (corresponding to the electrode M1 and the electrode N1 described above) and a second electrode 1304 (corresponding to the electrode M2 ​​and the electrode N2 described above). The human body communication chip 1301 and the processor 1302 are arranged on a printed circuit board (PCB), the human body communication chip 1301 is electrically connected to the first electrode 1303 and the second electrode 1304 respectively, the first electrode 1303 is not electrically connected to the human body, the second electrode 1304 is used to be electrically connected to the human body, and a dielectric 1305 is arranged on the side of the first electrode 1303 away from the second electrode 1304 to increase the equivalent capacitance between the first electrode 1303 and the ground terminal. The dielectric 1305 may or may not be in contact with the first electrode 1303. For example, the surface of the first electrode 1303 away from the second electrode 1304 is covered with the dielectric 1305. The dielectric 1305 may also be provided on one or more of the first electrodes 1303 away from the second electrode 1304.

[0078] The dielectric 1305 may be made of a high dielectric constant material. For example, the dielectric constant of the dielectric 1305 is greater than 4. The dielectric 1305 may be one of the following materials: alumina ceramics, zirconium oxide ceramics, polytetrafluoroethylene, polyimide, etc. In this way, the size of the first electrode 1303 can be made very small (for example, less than 1 cm*1 cm) to avoid interference with other metals.

[0079] The dielectric 1305 may be in close contact with the first electrode 1303, thereby increasing the equivalent capacitance between the first electrode 1303 and the ground terminal. The area of ​​the dielectric 1305 may be larger than the area of ​​the first electrode 1303. Within a certain range, the larger the area of ​​the dielectric 1305, the larger the equivalent capacitance between the first electrode 1303 and the ground terminal.

[0080] For example, Fig.13 As shown, taking the human body communication device 13 as a mobile phone as an example, the human body communication device 13 includes a metal middle frame 31, a back shell 32, and a display screen 33. The second electrode 1304 can be the metal middle frame 31 of the human body communication device 13 or other metals (such as metal frames) exposed to the outside of the electronic device. For human body communication devices such as mobile phones, the metal middle frame 31 is inherent, and there is no need to add additional metal parts, so the internal space can be saved. The human body communication chip 1301 and the processor 1302 are arranged on the metal middle frame 31. The first electrode 1303 can be an additional metal part, or it can be an antenna branch, or it can be a metal part of the camera module. For human body communication devices such as mobile phones, the antenna branch or the camera module is inherent, so no additional metal parts are added, saving internal space and material costs. The dielectric 1305 can be a piece of non-metallic part that is original or additionally set in the electronic device. Alternatively, the dielectric 1305 can be the back shell 32 of the human body communication device 13, so that the first electrode 1303 can be arranged on the inner side of the back shell 32 without being electrically connected to the human body. For a human body communication device such as a mobile phone, the back shell 32 is inherent, and no additional dielectric is required, thus saving internal space. In addition, compared with exposing the first electrode 1303 directly to the outside and contacting the human body, arranging the first electrode 1303 on the inner side of the back shell 32 can prevent huge transmission losses. Fig.14 As shown, after simulation of the actual environment, Fig.14 B is a back shell (dielectric 1305) added to the side of the first electrode 1303 away from the second electrode 1304. Fig.14 For medium A without adding a back shell, the signal attenuation of each frequency is reduced by about 5db on average.

[0081] In addition, the human body communication device includes an electrode electrically connected to the human body and an electrode not electrically connected to the human body, and human body communication is performed through these two electrodes. When the human body is close to the electrode not electrically connected to the human body, the human body communication performance will be reduced, and the closer the distance between the human body and the electrode, the more obvious the reduction in human body communication performance. Figure 5 As described in , when the human body is close to the electrode M1, capacitance will also be generated between the electrode M1 and the human body. As the human body gradually approaches the electrode M1, the equivalent capacitance C1 between the electrode M1 and the ground terminal will decrease, and the equivalent capacitance C2 between the human body and the electrode M1 will increase. In addition, Figure 7 As described in , a decrease in capacitance C1 may result in a decrease in the performance of human body communication.

[0082] Similarly, if Fig.15 As shown in A and B, the electrode M1 is the first electrode not electrically connected to the human body in human body communication as mentioned above. When the human body is close to the first electrode, the attraction of the human body to the electric field will also cause the equivalent capacitance between the first electrode and the ground terminal to decrease, resulting in a decrease in the performance of human body communication. Fig.16 As shown, when a single electrode is used, the user holds the mobile phone (corresponding to Fig.16 B) relative to the user not holding the phone (corresponding to Fig.16 Compared with (A), the signal attenuation of each frequency will increase by about 50db on average.

[0083] In order to solve the above problems, Fig.15 As shown in C, it is assumed that there are multiple first electrodes (for example, first electrode a and first electrode b), and the multiple first electrodes are electrically connected to the human body communication chip in parallel through a multi-open switch. When the human body is not close to the multiple first electrodes, the human body communication chip or processor controls the multi-open switch to connect the multiple first electrodes to the human body communication chip, that is, the multiple first electrodes work in parallel to increase the equivalent capacitance C1. Fig.15 As shown in D, when a human body approaches a first electrode (for example, first electrode b), if the multi-open switch still connects multiple first electrodes to the human body communication chip, the multiple first electrodes are still equivalent to one electrode, and the human body still has an attractive effect on the electric field of the multiple first electrodes. Fig.15 As shown in E, when a human body approaches a first electrode (for example, the first electrode b), the human body communication chip or processor controls the multi-open switch to disconnect the electrical connection between the human body communication chip and the first electrode (for example, the first electrode b), thereby reducing the influence of the human body on other first electrodes (for example, the first electrode a) without causing a significant decrease in the equivalent capacitance C1, thereby reducing the influence of the human body approaching the first electrode on the human body communication performance.

[0084] Specifically, Fig.17 and Fig.18As shown, an embodiment of the present application provides another human body communication device 13, including: a human body communication chip 1301 (corresponding to the first human body communication chip 111 or the second human body communication chip 121 described above), a processor 1302 (corresponding to the first processor 112 or the second processor 122 described above), a multi-open switch 1306, a second electrode 1304 (corresponding to the electrode M2 ​​and the electrode N2 described above) and a plurality of first electrodes (for example, 1303a, 1303b) (corresponding to the electrode M1 and the electrode N1 described above). The area of ​​the second electrode 1304 is greater than the area of ​​the plurality of first electrodes, so that the second electrode 1304 can couple capacitance with the plurality of first electrodes. The plurality of first electrodes can be arranged in different areas of the human body communication device 13 to avoid the plurality of first electrodes being affected by the human body at the same time, thereby reducing the human body communication performance. For example, the plurality of first electrodes can be located at the top and the middle of the human body communication device 13, respectively.

[0085] Optional, such as Fig.18 As shown, the human body communication device 13 also includes a dielectric (e.g., 1305a, 1305b) disposed on the side of the first electrode away from the second electrode 1304. Multiple first electrodes can be coupled to the same dielectric together, or each first electrode can be coupled to a dielectric (e.g., the first electrode 1303a is coupled to the dielectric 1305a, and the first electrode 1303b is coupled to the dielectric 1305b). Some first electrodes can also be coupled to the dielectric while the remaining first electrodes are not coupled to the dielectric, etc. For other contents about the human body communication chip 1301, the first electrode, the second electrode 1304, and the dielectric, please refer to the previous description and will not be repeated here.

[0086] The human body communication chip 1301 is connected to multiple first electrodes 1303 through a multi-open switch 1306. The human body communication chip 1301 or the processor 1302 can control the multi-open switch 1306 to connect the human body communication chip 1301 to at least one first electrode 1303 among the multiple first electrodes 1303, thereby executing the control method of the human body communication device involved in this application.

[0087] like Fig.19 As shown, the control method of the human body communication device provided by the present application includes:

[0088] S101. When a human body approaches the target first electrode, human body communication abnormality is detected.

[0089] The target first electrode is at least one first electrode among multiple first electrodes. Under default conditions, the multi-open switch 1306 connects multiple first electrodes to the human body communication chip 1301. Human body communication abnormalities include: the signal attenuation of human body communication increases by a certain amplitude, or the human body communication is disconnected, etc. Among them, the signal attenuation of human body communication increases by a certain amplitude means: the average power of the AC signal received by the human body communication chip in the first time period is the first power, and the average power of the AC signal received by the human body communication chip in the second time period thereafter is the second power, and the first power minus the second power is greater than the first threshold. Human body communication disconnection means that no AC signal can be received through the human body communication chip 1301.

[0090] S102, control the multi-open switch 1306 to disconnect the electrical connection between the human body communication chip 1301 and each first electrode respectively. When the electrical connection between the human body communication chip 1301 and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip 1301 and the target first electrode is kept disconnected; otherwise, the electrical connection between the human body communication chip 1301 and the target first electrode is restored.

[0091] Improved human body communication includes: the signal attenuation of human body communication is reduced by a certain amplitude, or the human body communication is restored and connected, etc. The signal attenuation of human body communication is increased by a certain amplitude, which means: the average power of the AC signal received by the human body communication chip in the third time period is the third power, and the average power of the AC signal received by the human body communication chip in the fourth time period is the fourth power, and the fourth power minus the third power is greater than the second threshold. The second threshold may be the same as or different from the first threshold. The restoration of human body communication connection means that the AC signal is received again through the human body communication chip 1301, etc.

[0092] If the human body communication is improved after disconnecting the target first electrode, it can be determined that the human body has a greater impact on the target first electrode, so the electrical connection between the human body communication chip 1301 and the target first electrode is disconnected. Otherwise (the human body communication performance has not increased), it can be determined that the human body has a smaller impact on the target first electrode, so the electrical connection between the human body communication chip 1301 and the target first electrode is restored to increase the equivalent capacitance between the first electrode and the ground terminal, thereby improving the human body communication performance.

[0093] Then, the electrical connection between the human body communication chip 1301 and other first electrodes is continuously disconnected until all first electrodes 1032 are traversed. At this point, it means that all first electrodes 1032 that are greatly affected by the human body have been disconnected, and the equivalent capacitance C1 between the first electrode 1032 and the ground terminal will not be greatly reduced, thereby reducing the influence of the human body approaching the first electrode 1032 on the human body communication performance.

[0094] For example, Fig. 20As shown in A, if the electrical connection between the human body communication chip 1301 and the first electrode 1303a is disconnected, the human body communication will not be improved. If the electrical connection between the human body communication chip 1301 and the first electrode 1303b is disconnected, the human body communication will be improved. Therefore, it can be determined that the target first electrode is the first electrode 1303b. Fig. 20 As shown in A, the electrical connection between the human body communication chip 1301 and the first electrode 1303b can be disconnected, and the electrical connection between the human body communication chip 1301 and the first electrode 1303a can be maintained. Fig. 20 As shown in C, when the user holds the mobile phone, the first electrode 1303b (corresponding to Fig. 20 B) and without disconnecting the first electrode 1303b (corresponding to Fig. 20 Compared with (A), the signal attenuation of each frequency will be reduced by about 6db on average.

[0095] The human body communication device, system and control method provided in the embodiments of the present application, multiple first electrodes that are not electrically connected to the human body are electrically connected to the human body communication chip through a multi-open switch. The human body communication chip or processor can control the multi-open switch to disconnect the first electrode among the multiple first electrodes that is greatly affected due to being close to the human body, thereby avoiding the first electrode from affecting other first electrodes, thereby avoiding the human body communication performance from being reduced when the human body is close to the electrode that is not electrically connected to the human body in the human body communication device.

[0096] The present application also provides a computer-readable storage medium, which includes instructions. When the instructions are executed on the human body communication device, the human body communication device executes each step in the above method embodiment, such as executing Fig.19 The method shown.

[0097] The present application also provides a computer program product including instructions. When the instructions are executed on the human body communication device, the human body communication device executes each step in the method embodiment, such as executing Fig.19 The method shown.

[0098] Regarding the technical effects of the computer-readable storage medium and the computer program product, refer to the technical effects of the previous method embodiments.

[0099] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0100] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0101] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0102] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one device or distributed on multiple devices. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0103] In addition, each functional module in each embodiment of the present application may be integrated into one device, or each module may exist physically separately, or two or more modules may be integrated into one device.

[0104] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or may contain one or more servers, data centers and other data storage devices that can be integrated with the medium. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state disk (SSD)).

[0105] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A human body communication device, characterized in that: include: A human body communication chip, a first electrode, a second electrode, and a dielectric; the human body communication chip is electrically connected to the first electrode and the second electrode respectively, and the dielectric is arranged on a side of the first electrode away from the second electrode; the first electrode is not electrically connected to the human body, and the second electrode is used to be electrically connected to the human body.

2. The device according to claim 1, characterized in that It also includes a processor and a multi-open switch, wherein there are a plurality of first electrodes, and the plurality of first electrodes are electrically connected in parallel to the human body communication chip through the multi-open switch; The human body communication chip or the processor is used to control the multi-open switch to connect the human body communication chip to at least one of the plurality of first electrodes.

3. The device according to claim 2, characterized in that The human body communication chip or the processor is specifically used for: Abnormal human body communication detected; The multi-open switch is controlled to disconnect the electrical connection between the human body communication chip and each first electrode respectively, wherein when the electrical connection between the human body communication chip and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip and the target first electrode is kept disconnected, otherwise the electrical connection between the human body communication chip and the target first electrode is restored.

4. The device according to claim 3, characterized in that The human body communication abnormality includes: human body communication disconnection; or, the average power of the AC signal received by the human body communication chip in a first time period is a first power, and the average power of the AC signal received by the human body communication chip in a second time period thereafter is a second power, and the first power minus the second power is greater than a first threshold.

5. The device according to claim 3 or 4, characterized in that The improvement in human body communication includes: the human body communication connection is restored; or, the average power of the AC signal received by the human body communication chip in a third time period is a third power, and the average power of the AC signal received by the human body communication chip in a subsequent fourth time period is a fourth power, and the fourth power minus the third power is greater than the second threshold.

6. The device according to any one of claims 2 to 5, characterized in that: The plurality of first electrodes are located in different areas of the human body communication device.

7. The device according to any one of claims 1 to 6, characterized in that: The dielectric is a back shell of the human body communication device, and the first electrode is arranged on the inner side of the back shell.

8. The device according to any one of claims 1 to 7, characterized in that: The dielectric is one of the following materials: alumina ceramics, zirconia ceramics, polytetrafluoroethylene, and polyimide.

9. The device according to any one of claims 1 to 8, characterized in that: The dielectric constant of the dielectric is greater than 4.

10. The device according to any one of claims 1 to 9, characterized in that: An area of ​​the dielectric is greater than an area of ​​the first electrode.

11. The device according to any one of claims 1 to 10, characterized in that: The first electrode is an antenna branch, or the first electrode is a metal component of a camera module.

12. The device according to any one of claims 1 to 11, characterized in that: The second electrode is a metal middle frame of the human body communication device.

13. A human body communication system, characterized in that: It comprises a first human body communication device and a second human body communication device, wherein the first human body communication device and the second human body communication device perform human body communication through the human body, and the first human body communication device or the second human body communication device is the human body communication device according to any one of claims 1-12.

14. A control method for a human body communication device, characterized in that: Applied to the human body communication device according to any one of claims 1 to 12, the method comprises: Abnormal human body communication detected; Control the multi-open switch to disconnect the electrical connection between the human body communication chip and each first electrode respectively, wherein when the electrical connection between the human body communication chip and the target first electrode is disconnected, if it is detected that the human body communication is improved, the electrical connection between the human body communication chip and the target first electrode is kept disconnected, otherwise the electrical connection between the human body communication chip and the target first electrode is restored; the first electrode is not electrically connected to the human body.

15. The method according to claim 14, characterized in that The human body communication abnormality includes: human body communication disconnection; or, the average power of the AC signal received by the human body communication chip in a first time period is a first power, and the average power of the AC signal received by the human body communication chip in a second time period thereafter is a second power, and the first power minus the second power is greater than a first threshold.

16. The method according to claim 14 or 15, characterized in that The improvement in human body communication includes: the human body communication connection is restored; or, the average power of the AC signal received by the human body communication chip in a third time period is a third power, and the average power of the AC signal received by the human body communication chip in a subsequent fourth time period is a fourth power, and the fourth power minus the third power is greater than the second threshold.

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