Magnetic bar antenna structure

Abstract

The invention discloses a magnetic bar antenna structure, which belongs to the technical field of communication, and comprises a connecting seat and three magnetic bar antennas, the magnetic bar antennas are magnetic bars which are orthogonal in pairs and are wound with coils, and the magnetic bar antennas are fixed on the connecting seat made of a non-magnetic material; the magnetic bar antennas are externally connected with resonance circuits respectively. Each resonance circuit comprises a resonance capacitor and a resonance inductor. The communication method of the magnetic bar antenna structure comprises the following steps: determining communication parameters according to communication requirements, and obtaining structure parameters of a magnetic bar antenna; the communication parameters comprise the minimum frequency bandwidth; calculating the distributed inductance of the magnetic rod antenna according to the obtained structural parameters; calculating a frequency bandwidth according to the calculated distributed inductance; judging whether the structural parameters of the magnetic bar antenna meet communication requirements or not according to the calculated frequency bandwidth; and when the calculated frequency bandwidth is greater than the obtained minimum frequency bandwidth, determining that the structural parameters of the magnetic bar antenna meet communication requirements. The problem that an existing communication coil is unstable in structure or high in manufacturing difficulty can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of communications, and in particular relates to a magnetic rod antenna structure. Background Art

[0002] Underwater communication technology has always been a cutting-edge technology in the field of communications and is often used in many fields such as underwater networks, underwater resource development, underwater cultural archaeology and military. Current underwater communication technologies mainly include underwater acoustic communication, underwater optical communication and underwater electromagnetic wave communication.

[0003] One of the major advantages of underwater acoustic communication technology is that it can cover a long transmission distance. However, this technology also faces significant challenges in its application, including the complexity and variability of the channel environment, significant propagation delay, and relatively low communication rate. The advantages of underwater optical communication are high speed and low attenuation, which are suitable for large-capacity information transmission in clear waters. However, when the water is turbid, the attenuation is aggravated, the communication distance is greatly shortened, and the equipment alignment requirements are very high, and it is easily affected by underwater lighting conditions.

[0004] In addition to these two communication methods, electromagnetic wave communication also shows certain application potential. However, the underwater wireless environment is completely different from that on land. In particular, electromagnetic waves will encounter high losses when propagating in the high-frequency band underwater, which requires the communication system to use low-frequency bands to achieve effective signal transmission. The reduction in frequency is accompanied by an increase in wavelength, which in turn requires the size of the communication antenna that transmits and receives electromagnetic waves to increase accordingly, which to some extent brings considerable difficulties to the miniaturization design of the equipment.

[0005] Underwater magnetic induction communication is a new underwater communication method in recent years. Its advantages are mainly reflected in its strong anti-electromagnetic interference ability and stable and reliable transmission. Since the magnetic field is not easily absorbed by water and the magnetic permeability of water is higher than that of air, magnetic induction communication can maintain stable signal transmission over a long distance, especially in complex underwater environments. In addition, this technology is not limited by light and is suitable for all-weather and all-time communications.

[0006] However, in the existing underwater magnetic induction communication, the coil communication has problems such as short communication distance, unstable structure, underwater displacement and sensitive communication angle, and the improved orthogonal omnidirectional coil, such as Figure 1 As shown, because it is a concentric antenna, very high requirements are placed on the manufacturing accuracy. Summary of the invention

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a magnetic rod antenna structure to solve the problem that the existing communication coil structure is unstable or difficult to manufacture.

[0008] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0009] In a first aspect, the present invention provides a magnetic rod antenna structure, comprising: a connecting seat and three magnetic rod antennas, wherein the magnetic rod antennas are magnetic rods wound with coils, the magnetic rod antennas are orthogonal to each other, the magnetic rod antennas are fixed to the connecting seat, and the connecting seat is made of non-magnetic material;

[0010] The magnetic rod antennas are respectively externally connected to a resonant circuit, and the resonant circuit includes a resonant capacitor and a resonant inductor;

[0011] The communication method of the magnetic rod antenna structure comprises:

[0012] S1: Determine the communication parameters according to the communication requirements and obtain the structural parameters of the magnetic rod antenna;

[0013] The communication parameters include a minimum frequency bandwidth;

[0014] S2: Calculate the distributed inductance of the magnetic rod antenna according to the structural parameters obtained in step S1;

[0015] S3: Calculate the frequency bandwidth according to the distributed inductance calculated in step S2;

[0016] S4: judging whether the structural parameters of the magnetic rod antenna meet the communication requirements according to the frequency bandwidth calculated in step S3;

[0017] When the frequency bandwidth calculated in step S3 is greater than the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna meet the communication requirements.

[0018] In the aforementioned magnetic rod antenna structure, the communication parameters in step S1 also include a communication frequency, and the communication frequency determined in step S1 is set as the resonant frequency of the resonant circuit.

[0019] In the aforementioned magnetic rod antenna structure, the step S3 comprises:

[0020] S31: Calculate the quality factor of the magnetic rod antenna according to the distributed inductance calculated in step S2, the communication frequency determined in step S1 and the obtained structural parameters of the magnetic rod antenna;

[0021] The structural parameters of the magnetic rod antenna include the distributed resistance of the magnetic rod antenna. Quality factor The calculation formula is: ,in, Indicates a magnetic rod antenna The distributed inductance; Indicates a magnetic rod antenna The distributed resistance; Indicates the communication frequency;

[0022] S32: Calculate the frequency bandwidth according to the quality factor calculated in step S31,

[0023] The magnetic rod antenna Frequency bandwidth The calculation formula is .

[0024] For the aforementioned magnetic rod antenna structure, when step S4 determines that the structural parameters of the magnetic rod antenna meet the communication requirements, the communication method of the magnetic rod antenna structure further includes:

[0025] S5: Calculate the resonant capacitance of the resonant circuit according to the resonant inductance given by the resonant circuit, the communication frequency determined in step S1 and the distributed inductance calculated in step S2.

[0026] The aforementioned magnetic rod antenna structure, step S4 further includes: when the frequency bandwidth calculated in step S3 is less than or equal to the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna do not meet the communication requirements;

[0027] When step S4 determines that the structural parameters of the magnetic rod antenna do not meet the communication requirements, the structural parameters of the magnetic rod antenna are adjusted. The method for adjusting the structural parameters of the magnetic rod antenna includes: reducing the number of coil turns of the magnetic rod antenna and / or increasing the length of the magnetic rod of the magnetic rod antenna.

[0028] The aforementioned magnetic rod antenna structure, the communication method of the magnetic rod antenna structure also includes:

[0029] S6: using the resonant circuit whose resonant capacitor parameters are determined in step S5 for signal transmission required by the communication in step S1;

[0030] S7: When the communication requirement of step S1 is changed, jump to step S2 to calculate the distributed inductance of the magnetic rod antenna.

[0031] In the aforementioned magnetic rod antenna structure, the output of the resonant circuit is connected to a voltage comparison circuit, and the voltage comparison circuit is used to select and output the signal with the highest voltage in the resonant circuit.

[0032] In the aforementioned magnetic rod antenna structure, the output of the voltage comparison circuit is connected to an amplifier circuit, and the output of the amplifier circuit is connected to a demodulation circuit. The amplifier circuit is used to amplify and enhance the output of the voltage comparison circuit, and the demodulation circuit is used to demodulate the received signal.

[0033] In the aforementioned magnetic rod antenna structure, the structural parameters of the three magnetic rod antennas are the same.

[0034] The aforementioned magnetic rod antenna structure, when the magnetic rod antenna structure is used to send signals, the magnetic rod antenna is connected to an amplifying circuit and a resonant circuit, and the signal sending process includes: the signal source transmits the signal to the magnetic rod antenna through the resonant circuit and the amplifying circuit in sequence, and the magnetic rod antenna transmits the received signal to the receiving end through electromagnetic induction.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present invention adopts an orthogonal magnetic rod antenna structure to replace the existing coil structure design. Three magnetic rod antennas are orthogonally arranged in pairs, which ensures the comprehensiveness of the received signal direction while solving the problem of unstable structure or high manufacturing difficulty of the existing communication coil.

[0037] The magnetic rod antenna of the present invention has a stable structure, reduces the probability of displacement when used underwater, reduces the influence of underwater displacement on the communication angle, avoids the problem of high manufacturing precision of concentric circle antennas, and utilizes the principles of omnidirectional signal reception and electromagnetic induction, so that the magnetic rod antenna structure of the present invention can maintain stable signal transmission over a long distance.

[0038] The communication method of the magnetic rod antenna structure of the present invention provides a verification method for the communication capability of the magnetic rod antenna, and can determine whether the structural parameters of the magnetic rod antenna meet the communication requirements according to the communication requirements;

[0039] When the communication requirements are met, the circuit parameters of the magnetic rod antenna resonant circuit are further calculated to specifically improve the signal receiving capability of the magnetic rod antenna structure;

[0040] When the communication requirements are met, the present invention provides corresponding adjustment measures until the communication requirements are met;

[0041] When the communication demand changes, the present invention provides a communication method of the magnetic rod antenna structure with adaptive adjustment, so that the magnetic rod antenna structure of the present invention can adapt to more application scenarios.

[0042] The magnetic rod antenna structure of the present invention improves the multi-angle receiving capability of underwater magnetic induction while being compatible with the good communication capability of the magnetic rod antenna, and the manufacturing difficulty is greatly reduced due to the design of non-same center. The present invention also provides a design method for antenna parameters, which effectively reduces the coupling mutual inductance between antennas through parameter calculation, reduces the loss caused by the coupling mutual inductance between the magnetic rod antennas of the magnetic rod antenna structure, and improves the communication distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the structure of the existing orthogonal omnidirectional coil;

[0044] Figure 2 is a schematic structural diagram of a magnetic rod antenna according to Embodiment 1 of the present invention;

[0045] Figure 3 is a circuit diagram of the magnetic rod antenna structure connection of embodiment 1 of the present invention;

[0046] Figure 4 It is a schematic diagram of a model of signal transmission between a transmitting end TX and a receiving end RX magnetic rod antenna structure in Embodiment 1 of the present invention;

[0047] Figure 5 It is embodiment 1 of the present invention Figure 4 Equivalent circuit diagram of the model;

[0048] Figure 6 It is the equivalent circuit diagram of the electromagnetic induction principle;

[0049] Figure 7 is the angle factor in the embodiment 1 of the present invention Schematic diagram;

[0050] Figure 8 is the angle factor in the embodiment 1 of the present invention Schematic diagram;

[0051] Fig. 9 It is embodiment 1 of the present invention Figure 4 A simplified equivalent circuit diagram of the model;

[0052] Fig.10 It is a flowchart of the communication method of the magnetic rod antenna structure of embodiment 2 of the present invention. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0054] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0055] Embodiment 1:

[0056] This embodiment introduces a magnetic rod antenna structure, including a connecting seat and three magnetic rod antennas, wherein the magnetic rod antennas are magnetic rods wound with coils, the magnetic rod antennas are orthogonal to each other, the magnetic rod antennas are fixed to the connecting seat, and the connecting seat is made of non-magnetic material;

[0057] The magnetic rod antennas are respectively externally connected to a resonant circuit, and the resonant circuit includes a resonant capacitor and a resonant inductor.

[0058] The magnetic rod antenna structure introduced in this embodiment solves the problem that the existing communication coil structure is unstable or difficult to manufacture.

[0059] In this embodiment, if Figure 2 As shown, the magnetic rod antenna structure is a three-dimensional Cartesian coordinate axis structure, with magnetic rod antennas in the three directions of X, Y, and Z respectively. The structural parameters of the three magnetic rod antennas are the same, and the three magnetic rod antennas all use magnetic rods of the same material and volume. The coils of the magnetic rod antennas are wound with wires of the same material. Each magnetic rod antenna is connected to a subsequent circuit, and the connecting seat is made of non-magnetic material to prevent coupling between the magnetic rods. The shape of the connecting seat is any shape that is convenient for fixing and installing the magnetic rod antenna. In this embodiment, the connecting seat is a cube structure.

[0060] The circuit structure of the magnetic rod antenna structure in this embodiment is as follows Figure 3 As shown, the output of the resonant circuit is connected to a voltage comparison circuit, and the voltage comparison circuit is used to select and output the signal with the highest voltage in the resonant circuit. The output of the voltage comparison circuit is connected to an amplifier circuit, and the output of the amplifier circuit is connected to a demodulation circuit, and the amplifier circuit is used to amplify and enhance the output of the voltage comparison circuit, and the demodulation circuit is used to demodulate the received signal.

[0061] The resonant circuit is an RLC oscillation circuit composed of resistance, capacitance and inductance. The circuit should take into account the structural parameters of each magnetic rod antenna, so as to give the resonant circuit a new resonant frequency, so as to achieve the function of modifying the resonant frequency according to the communication frequency to improve the receiving efficiency and quality. In addition, an amplifier circuit is added at the end of the resonant circuit to amplify the signal, so as to facilitate the next step of demodulation;

[0062] A voltage comparison circuit is provided at the front end of the amplifier circuit, so as to select the signal with the highest voltage value, so as to facilitate the preferred amplification of the received signal and then demodulation according to the corresponding demodulation method, so as to receive the required information;

[0063] In the process of signal reception, the resonant circuit can act as a filter to make the response at a specific frequency larger, thereby selectively amplifying the signal at a specific frequency. In this way, the magnetic rod antenna can only receive electromagnetic waves in a specific frequency band, improving the sensitivity and selectivity of reception.

[0064] When the frequency of the received electromagnetic wave matches the resonant frequency of the resonant circuit, the current in the circuit reaches its maximum value, thereby maximizing the coupling of energy from the transmitting antenna and improving the receiving efficiency.

[0065] The resonant circuit can also adjust its quality factor according to the bandwidth requirements to meet the requirements of signal distortion-free, ensuring that the received signal is clear and accurate.

[0066] The resonant circuit and the subsequent circuit can be connected through a signal coupler. The function of the signal coupler is to effectively transmit the signal output by the resonant part to the subsequent circuit. This is usually achieved by electromagnetic induction, capacitive coupling or transformer coupling.

[0067] Amplifier circuit input: The amplification part can be a transistor amplifier, an operational amplifier or other types of amplifiers. The signal output by the voltage comparison circuit is used as the input signal of the amplifier. After the amplification of the amplifier, the signal is enhanced.

[0068] Output matching: The output of the amplifier usually needs to pass through an output matching network to ensure that the amplified signal can be efficiently transmitted to the load or subsequent circuit. The design of the output matching network also needs to consider impedance matching to reduce signal reflection and loss.

[0069] During the transmission of electrical signals, signal couplers can ensure that signals are transmitted efficiently between two circuits while reducing signal loss and interference.

[0070] However, signal couplers are not required in all cases. In some simple circuit designs, the resonant circuit and the subsequent circuit can be directly connected without an additional signal coupler. This usually happens when there are fewer circuit elements, the signal transmission path is short, and the signal quality requirements are not high. For example, a transformer can be used for coupling to achieve signal transmission and amplification through magnetic field interaction. This connection method may have better performance in some specific application scenarios.

[0071] like Figure 3 As shown, the present invention uses the voltage comparison of the outputs of the three groups of resonant circuits through the voltage comparison circuit U1, outputs the signal with the highest voltage, and transmits the signal as input to the amplifier circuit U2 for amplification and enhancement. The output of the amplifier circuit U2 is connected to the demodulation circuit U3, and the received signal with the largest voltage value is demodulated to ensure that the demodulated signal is the optimal signal, which is convenient for subsequent circuit processing. This method of first comparing and then amplifying saves the number of amplifier circuits and reduces circuit costs.

[0072] like Figure 2As shown, the magnetic rod antenna structure is an antenna established by analogy with the Cartesian coordinate system. At the 0 point is a cube of non-magnetic material, through which the magnetic rod antennas are connected. The magnetic rod antennas are mostly composed of magnetic rods made of manganese-zinc material and tightly wound coils. The wound coils must be tight, leaving no space as much as possible. Only in this way can the generation of parasitic capacitance between coils be avoided to the greatest extent. The magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az are three magnetic rod antennas with the same structural parameters, and the number of turns of the coil of each magnetic rod antenna is N.

[0073] like Figure 3 As shown, the magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az will extend two terminals, which will be connected to the subsequent resonant circuits. Each circuit will have three resonant inductors with the same parameters, Lx, Lz and Ly, three resonant capacitors with the same parameters, Cx, Cz and Cy, and three distributed resistors with the same parameters, R1, R2 and R3, which together form three RLC resonant circuits. Lx, Cx and R1 form the resonant circuit of the magnetic rod antenna Ax, Ly, Cy and R2 form the resonant circuit of the magnetic rod antenna Ay, and Lz, Cz and R3 form the resonant circuit of the magnetic rod antenna Az. The function of these resonant circuits is to match the antenna resonant frequency with the communication frequency, and the maximum received signal will be obtained when resonating.

[0074] like Figure 3 As shown, when the antenna is in the communication state, the magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az will all receive signals, these signals will be compared by the voltage comparison circuit U1, and the signal with the largest amplitude will be selected and demodulated by the demodulation circuit at U2.

[0075] like Figure 4 As shown in the model of signal transmission between the transmitting end TX and the receiving end RX, the transmitting end adopts a magnetic rod antenna or a coil for transmission, and the three magnetic rod antennas of the magnetic rod antenna structure of the receiving end respectively receive signals.

[0076] Figure 4 The equivalent circuit of the signal transmission model is as follows Figure 5 As shown, R txrx , R txry and R txrz are the mutual inductance resistances generated by the transmitter TX to the magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az of the receiver RX respectively; R rxtx , R rytx and R rztx are the mutual inductances generated by the magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az to the transmitting end TX respectively; the mutual inductances generated by the above transmitting end to the same receiving end and by the receiving end to the transmitting end are the same. ryrx , R rzrx , R rxry, R ryry , R rxr z and R ryrz It is the mutual inductance resistance generated between the three magnetic rod antennas Ax, Ay and Az.

[0077] The working principle of the magnetic rod antenna structure of the present invention is described as follows:

[0078] 1.1 Mutual inductance of coupled magnetic bar coils

[0079] The basic principle of magnetic induction communication is to use the magnetic field as a medium for information transmission, to transmit information by generating a changing magnetic field through a transmitting antenna, and to use a receiving antenna in the receiver to detect the magnetic field changes and convert them into electrical signals, thereby realizing wireless transmission of information. Figure 6 As shown, the mutual inductance coefficient M is a physical quantity used to describe the degree of mutual influence between two coils.

[0080] 1.2 Magnetic Rod Antenna Structure

[0081] When the distances between multiple coils are very short, crosstalk between the coils will be caused, thereby affecting the reception effect. Current researchers use orthogonal three-dimensional coils with the same center for research, while the present invention studies the magnetic rod antenna structure with non-same center. The magnetic rod antenna structure of the present invention is as follows: Figure 2 shown.

[0082] The centers of the three magnetic rod antennas are not at the same point. According to Stokes' theorem, the calculation formula for the mutual inductance M between two magnetic rod antennas at any position is:

[0083] ,

[0084] in, is the transmission environment permeability, is the number of coil turns, is the coil radius, is the distance between the geometric midpoints of the two coils that produce mutual inductance, is the angle factor, which is determined by the attitude of the antenna.

[0085] When the transmission environment is water, the magnetic permeability of the water is 1.

[0086] The angle factor is calculated as:

[0087] ,

[0088] Among them, Figure 7 and Figure 8 As shown, The connecting lines l are the geometric centers O1 and O2 of the coils of the two magnetic rod antennas.12 The angle between the coil and the radial section of each coil; Figure 8 As shown, The radial cross-section normals N1 and N2 of the coils of the two magnetic rod antennas are connected to the lines l of the geometric centers O1 and O2 of the two coils respectively. 12 The angle between the two projection lines p1 and p2 generated by the projection of the vertical plane S12.

[0089] like Figure 5 In the equivalent circuit structure shown, the calculation of each parameter is as follows:

[0090]

[0091] Among them, R xL , R yL and R zL are the equivalent impedances of the resonant inductors of the resonant circuits of the magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az respectively; R txL is the equivalent impedance of the resonant inductor of the transmitting end TX resonant circuit; R1, R2 and R3 are the distributed resistances of the magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az respectively; M txrx 、M txry and M txrz is the mutual inductance coefficient generated by the transmitter to the receiving end magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az respectively; M rxtx 、M rytx and M rztx It is the mutual inductance coefficient generated by the receiving end magnetic rod antenna Ax, magnetic rod antenna Ay and magnetic rod antenna Az to the transmitting end respectively; the mutual inductance coefficient generated by the transmitting end to the same receiving end and by the receiving end to the transmitting end is the same.

[0092] , and are the distances between the geometric midpoints of the two coils that generate mutual inductance with the magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az at the transmitting end, respectively. , and are the angle factors between the transmitting end and the magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az respectively.

[0093] The magnetic rod antennas of the magnetic rod antenna structure of the present invention are orthogonal to each other, so the mutual inductance coefficient between the magnetic rod antennas is calculated as follows:

[0094] ,

[0095] in, It is the distance between the geometric midpoints of the coils of the magnetic rod antennas of the present invention.

[0096] Since the magnetic rod antennas at the receiving end are placed vertically and orthogonally to each other, that is,

[0097]

[0098] Therefore, the mutual inductance coefficient between two of the three magnetic rod antennas of the magnetic rod antenna structure of the present invention will be zero.

[0099] When the mutual inductance coefficient between the three magnetic rod antennas is 0, we can further obtain:

[0100] Therefore, the equivalent circuit diagram of the transmission and reception model of the present invention can be simplified as follows: Fig. 9 As shown, the equivalent circuit of the magnetic rod antenna Ax includes distributed resistance R1, equivalent inductive reactance and equivalent capacitive reactance The distributed resistance is the resistance value of the magnetic rod antenna itself. In order to calculate the equivalent impedance of the equivalent circuit, it is also necessary to calculate the equivalent inductive reactance and equivalent capacitive reactance in each magnetic rod antenna equivalent circuit. Since the circuit parameters in the resonant circuit are the same, it is only necessary to calculate the equivalent inductive reactance and equivalent capacitive reactance of one magnetic rod antenna equivalent circuit. The calculation is as follows:

[0101]

[0102] The equivalent impedance of a magnetic rod antenna equivalent circuit is calculated as follows:

[0103]

[0104] According to Kirchhoff's law, the received voltage of the magnetic rod antenna Ax, the magnetic rod antenna Ay and the magnetic rod antenna Az is calculated as follows:

[0105]

[0106] in, is the electrical signal voltage at the sending end.

[0107] Combined with the previous theory, it can be inferred that when the transmitting end is a single magnetic rod antenna, when the magnetic rod antenna of the transmitting end and one magnetic rod antenna of the magnetic rod antenna structure of the receiving end are set in parallel, the induced voltage of the magnetic rod antenna at the receiving end reaches the maximum. At the same time, the magnetic rod antenna of the receiving end is set vertically to the remaining two magnetic rod antennas of the magnetic rod antenna structure of the receiving end, and the induced voltage of the two magnetic rod antennas at the receiving end is the smallest.

[0108] When the transmitting end is the same magnetic rod antenna structure as the present invention, and when the magnetic rod antenna structures of the transmitting end and the receiving end are arranged in the same direction, the three magnetic rod antennas of the transmitting end are arranged in parallel with one magnetic rod antenna of the receiving end in one-to-one correspondence, that is, the lengths of the lines connecting the geometric centers of the three magnetic rod antenna coils of the transmitting end and the geometric centers of the magnetic rod antenna coils of the corresponding parallel arrangement at the receiving end are equal, which can be expressed as: ; Accordingly, the angle factors of the three magnetic rod antennas at the transmitting end and the corresponding magnetic rod antennas arranged in parallel at the receiving end are equal, which can be expressed as ,

[0109] .

[0110] Embodiment 2:

[0111] Based on the same inventive concept as the first embodiment, on the basis of the magnetic rod antenna structure of the first embodiment, as Fig.10 As shown, the communication method of the magnetic rod antenna structure includes:

[0112] S1: Determine the communication parameters according to the communication requirements and obtain the structural parameters of the magnetic rod antenna coil;

[0113] The communication parameters include a minimum frequency bandwidth;

[0114] S2: Calculate the distributed inductance of the magnetic rod antenna according to the structural parameters obtained in step S1;

[0115] S3: Calculate the frequency bandwidth according to the distributed inductance calculated in step S2;

[0116] S4: judging whether the structural parameters of the magnetic rod antenna meet the communication requirements according to the frequency bandwidth calculated in step S3;

[0117] When the frequency bandwidth calculated in step S3 is greater than the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna meet the communication requirements.

[0118] Step S1 includes:

[0119] S11: Determine communication parameters according to communication requirements, where the communication parameters include, for example, communication distance d, communication frequency f, and minimum frequency bandwidth.

[0120] The transmitter applies an alternating voltage to excite the antenna or transmission line, thereby generating an alternating current. The alternating current forms an alternating electromagnetic field around the transmitter, that is, electromagnetic waves. The frequency of these electromagnetic waves is the same as the frequency of the applied alternating voltage.

[0121] S12: Obtain the structural parameters of the magnetic rod antenna, including the effective magnetic permeability of the magnetic rod of the magnetic rod antenna. , the number of turns of the magnetic rod antenna coil N, the radius of the magnetic rod antenna coil a (or the cross-sectional area of ​​the magnetic rod antenna coil S), the distributed resistance of the magnetic rod antenna and the length of the magnetic rod of the magnetic rod antenna .

[0122] In this embodiment, when the magnetic rod antenna structure of the present invention is used to receive signals, the communication frequency determined in step S1 is set as the resonant frequency of the resonant circuit, so that the magnetic rod antenna structure of the present invention can obtain a better signal receiving effect.

[0123] In step S2, the calculation formula for calculating the distributed inductance of the magnetic rod antenna according to the structural parameters obtained in step S1 is:

[0124]

[0125] in, is the effective magnetic permeability of the magnetic rod antenna, N is the number of turns of the magnetic rod antenna coil, is the cross-sectional area of ​​the coil, is the length of the magnetic bar.

[0126] Step S3 includes:

[0127] S31: Calculate the quality factor of the magnetic rod antenna according to the distributed inductance calculated in step S2, the communication frequency determined in step S1 and the obtained structural parameters of the magnetic rod antenna;

[0128] The structural parameters of the magnetic rod antenna include the distributed resistance of the magnetic rod antenna. Quality factor The calculation formula is: ,in, Indicates a magnetic rod antenna The distributed inductance; Indicates a magnetic rod antenna The distributed resistance; Indicates the communication frequency;

[0129] S32: Calculate the frequency bandwidth according to the quality factor calculated in step S31,

[0130] The magnetic rod antenna Frequency bandwidth The calculation formula is .

[0131] Step S4 also includes: when the frequency bandwidth calculated in step S3 is less than or equal to the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna do not meet the communication requirements;

[0132] When step S4 determines that the structural parameters of the magnetic rod antenna do not meet the communication requirements, the structural parameters of the magnetic rod antenna are adjusted. The method for adjusting the structural parameters of the magnetic rod antenna includes: reducing the number of coil turns of the magnetic rod antenna and / or increasing the length of the magnetic rod of the magnetic rod antenna.

[0133] When step S4 determines that the structural parameters of the magnetic rod antenna meet the communication requirements, the communication method of the magnetic rod antenna structure further includes:

[0134] S5: Calculate the resonant capacitance of the resonant circuit according to the resonant inductance given by the resonant circuit, the communication frequency determined in step S1 and the distributed inductance calculated in step S2.

[0135] The specific process includes:

[0136] S51: Calculate the total inductance based on the resonant inductance given by the resonant circuit and the distributed inductance calculated in step S2 ,

[0137] S52: According to the resonant frequency formula , which is transformed into , calculate the resonant capacitance of the resonant circuit.

[0138] The communication method of the magnetic rod antenna structure also includes:

[0139] S6: using the resonant circuit whose resonant capacitor parameters are determined in step S5 for the communication required in step S1;

[0140] S7: When the communication requirement of step S1 is changed, jump to step S2 to calculate the distributed inductance of the magnetic rod antenna.

[0141] Step 31 Calculate the quality factor It is an important indicator to judge the transceiver capability of magnetic rod antenna. Quality factor For example , and so on, we can get , since the parameters of the magnetic rod antenna in three directions are equal, .

[0142] Step S32 calculates the frequency bandwidth The frequency bandwidth of the magnetic rod antenna determines the frequency range in which the signal can be transmitted, thus affecting the transmission rate and information capacity of the system. When the frequency bandwidth of the receiving magnetic rod antenna is greater than the minimum bandwidth of the signal, the structural parameters of the magnetic rod antenna meet the communication requirements.

[0143] In this embodiment,

[0144] Step S1 includes:

[0145] S11: Determine the communication parameters according to the communication requirements, the communication frequency f=150kHz, and the minimum frequency bandwidth BW=1kHz;

[0146] S12: Obtain structural parameters of the magnetic rod antenna, the structural parameters include: Effective magnetic permeability of a bar magnet 11.97, magnetic rod antenna Coil turns N=80, magnetic rod antenna The cross-sectional area of ​​the coil is 1 cm 2 , Distributed resistance of magnetic rod antenna 1.5Ω and ferrite rod antenna Length of the magnetic bar is 4cm.

[0147] In step S2, according to Calculating distributed inductance 191.52uH;

[0148] Step S3 includes:

[0149] S31: Calculation of ferrite rod antenna Quality factor , Distributed resistance of magnetic rod antenna is 1.5Ω, and the magnetic rod antenna is calculated Quality factor It is 120.34.

[0150] By analogy, we can get and Since the structural parameters of the three magnetic rod antennas of the present invention are equal, , the quality factor is 120.34.

[0151] S32: Calculation of ferrite rod antenna Frequency bandwidth The frequency bandwidth is 1.247kHz, and the frequency bandwidth is calculated to be 1.247kHz, which meets the minimum frequency bandwidth of 1kHz. The structural parameters of the magnetic rod antenna do not meet the communication requirements.

[0152] When step S4 determines that the structural parameters of the magnetic rod antenna meet the communication requirements, the communication method of the magnetic rod antenna structure further includes:

[0153] S5: Calculate the resonant capacitance of the resonant circuit according to the resonant inductance given by the resonant circuit, the communication frequency determined in step S1 and the distributed inductance calculated in step S2.

[0154] S51: Ferrite Rod Antenna Distributed inductance and Figure 3 The resonant inductance of the resonant circuit shown is in series. The given resonant inductance is 10mH. The total inductance It is 10.19152mH.

[0155] S52: Resonant capacitor of the resonant circuit , the resonant capacitor Cx should be 110.46pF.

[0156] The resonant capacitors Cy and Cz of the other two resonant circuits are selected to have the same value as the resonant capacitor Cx.

[0157] When the magnetic rod antenna structure is used to send signals, the magnetic rod antenna is connected to an amplifying circuit and a resonant circuit. The signal sending process includes: the signal source transmits the signal to the magnetic rod antenna through the resonant circuit and the amplifying circuit in sequence, and the magnetic rod antenna transmits the received signal to the receiving end through electromagnetic induction.

[0158] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0159] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0160] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0161] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0162] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A magnetic rod antenna structure, characterized in that: It includes a connecting seat and three magnetic rod antennas, wherein the magnetic rod antennas are magnetic rods wound with coils, the magnetic rod antennas are orthogonal to each other, the magnetic rod antennas are fixed to the connecting seat, and the connecting seat is made of non-magnetic material; The magnetic rod antennas are respectively externally connected to a resonant circuit, wherein the resonant circuit includes a resonant capacitor and a resonant inductor; The communication method of the magnetic rod antenna structure comprises: S1: Determine the communication parameters according to the communication requirements and obtain the structural parameters of the magnetic rod antenna; The communication parameters include a minimum frequency bandwidth; S2: Calculate the distributed inductance of the magnetic rod antenna according to the structural parameters obtained in step S1; S3: Calculate the frequency bandwidth according to the distributed inductance calculated in step S2; S4: judging whether the structural parameters of the magnetic rod antenna meet the communication requirements according to the frequency bandwidth calculated in step S3; When the frequency bandwidth calculated in step S3 is greater than the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna meet the communication requirements.

2. The magnetic rod antenna structure according to claim 1, characterized in that: The communication parameters in step S1 also include a communication frequency, and the communication frequency determined in step S1 is set as the resonant frequency of the resonant circuit.

3. The magnetic rod antenna structure according to claim 2, characterized in that: The step S3 comprises: S31: Calculate the quality factor of the magnetic rod antenna according to the distributed inductance calculated in step S2, the communication frequency determined in step S1 and the obtained structural parameters of the magnetic rod antenna; The structural parameters of the magnetic rod antenna include the distributed resistance of the magnetic rod antenna. Quality factor The calculation formula is: ,in, Indicates a magnetic rod antenna The distributed inductance; Indicates a magnetic rod antenna The distributed resistance; Indicates the communication frequency; S32: Calculate the frequency bandwidth according to the quality factor calculated in step S31, The magnetic rod antenna Frequency bandwidth The calculation formula is .

4. The magnetic rod antenna structure according to claim 2, characterized in that: When step S4 determines that the structural parameters of the magnetic rod antenna meet the communication requirements, the communication method of the magnetic rod antenna structure further includes: S5: Calculate the resonant capacitance of the resonant circuit according to the resonant inductance given by the resonant circuit, the communication frequency determined in step S1 and the distributed inductance calculated in step S2.

5. The magnetic rod antenna structure according to claim 1, characterized in that: Step S4 also includes: when the frequency bandwidth calculated in step S3 is less than or equal to the minimum frequency bandwidth obtained in step S1, the structural parameters of the magnetic rod antenna do not meet the communication requirements; When step S4 determines that the structural parameters of the magnetic rod antenna do not meet the communication requirements, the structural parameters of the magnetic rod antenna are adjusted. The method for adjusting the structural parameters of the magnetic rod antenna includes: reducing the number of coil turns of the magnetic rod antenna and / or increasing the length of the magnetic rod of the magnetic rod antenna.

6. The magnetic rod antenna structure according to claim 4, characterized in that: The communication method of the magnetic rod antenna structure also includes: S6: using the resonant circuit whose resonant capacitor parameters are determined in step S5 for signal transmission required by the communication in step S1; S7: When the communication requirement of step S1 is changed, jump to step S2 to calculate the distributed inductance of the magnetic rod antenna.

7. The magnetic rod antenna structure according to any one of claims 1 to 6, characterized in that: The output of the resonant circuit is connected to a voltage comparison circuit, and the voltage comparison circuit is used to select and output the signal with the highest voltage in the resonant circuit.

8. The magnetic rod antenna structure according to claim 7, characterized in that: The output of the voltage comparison circuit is connected to an amplifier circuit, and the output of the amplifier circuit is connected to a demodulation circuit. The amplifier circuit is used to amplify and enhance the output of the voltage comparison circuit, and the demodulation circuit is used to demodulate the received signal.

9. The magnetic rod antenna structure according to any one of claims 1 to 8, characterized in that: The three magnetic rod antennas have the same structural parameters.

10. The magnetic rod antenna structure according to any one of claims 1 to 9, characterized in that: When the magnetic rod antenna structure is used to send signals, the magnetic rod antenna is connected to an amplifying circuit and a resonant circuit. The signal sending process includes: the signal source transmits the signal to the magnetic rod antenna through the resonant circuit and the amplifying circuit in sequence, and the magnetic rod antenna transmits the received signal to the receiving end through electromagnetic induction.

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