Conical antenna based airborne target charge telemetry system and method

Abstract

The application provides a kind of air target electric charge telemetry system based on conical antenna, comprising: electrostatic field sensor unit, shielded cable, digital signal processing unit;The electrostatic field sensor unit includes at least 3 conical antennas and front-end signal conditioning circuit;Each of the conical antenna inductively obtains the electrostatic field variation characteristic information of air flight target;The front-end signal conditioning circuit is connected with the conical antenna respectively, and the charge variation characteristic signal is converted into voltage characteristic amplitude signal;One end of the shielded cable is connected with the front-end signal conditioning circuit, and the other end is connected with the digital signal processing unit, for transmitting the voltage characteristic amplitude signal converted by the front-end signal conditioning circuit;The digital signal processing unit carries out hardware filtering, digital sampling and digital filtering processing to voltage characteristic amplitude signal.The application has the characteristics of flexible electrostatic field sensor layout, unrestricted target flight path and high detection accuracy.

Description

Technical Field

[0001] This invention belongs to the field of telemetry of the charge of flying targets, specifically relating to a telemetry system and method for the charge of airborne targets based on a conical antenna, which is applied to the charge measurement of airborne flying targets. Background Technology

[0002] The electrostatic field generated during target movement is a usable information source. Any object using an engine or moving will inevitably acquire static electricity due to various charging processes. The theoretical basis of electrostatic detection is the principle of electrostatic fields. By detecting the electrostatic field around the target, target information can be obtained. It has technical advantages such as high accuracy in azimuth detection and strong anti-interference ability, and has broad application prospects in atmospheric electrostatic field detection, precise target detection, and other fields.

[0003] Currently, research on the characteristics of electrostatic targets in China is still in the qualitative analysis stage, and numerical simulation analysis can no longer meet the needs of the engineering application of electrostatic technology. At the same time, high-speed dynamic field tests have disadvantages such as long test cycles and high costs. There is an urgent need to conduct research on telemetry methods for the charge of airborne targets, obtain the characteristics of the target charge, and provide data support for the parameter design of electrostatic detection systems.

[0004] In existing technologies, circular electrode cylinders are used to test the charge of targets. During the detection process, the flying target needs to pass through the circular electrode cylinder, and it can only detect small projectile-like aerial targets, not large-volume flying targets. In addition, the electrostatic potential is directly measured to measure the potential of helicopters. This system requires connecting the helicopter to the test system through high-voltage wires, which has disadvantages such as high risk and complex testing. Alternatively, a flat-plate electric field sensor is used to detect the charge characteristics of flying targets. Since this detection system is a flat-plate inductive electrode and uses a current-coupled detection method, the output is a zero-crossing intersection curve, which has the defect of insufficient charge estimation accuracy. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings and defects in the existing technology and provide an airborne target charge telemetry system and method based on a conical antenna, which has the characteristics of flexible electric field sensor deployment, unrestricted target flight path, and high detection accuracy.

[0006] To achieve the above objectives, the present invention provides an aerial target charge telemetry system based on conical antennas, comprising: an electrostatic field sensor unit, a shielded cable, and a digital signal processing unit; the electrostatic field sensor unit includes at least three conical antennas and a front-end signal conditioning circuit; each conical antenna senses and acquires electrostatic field change characteristic information of an aerial flying target; the front-end signal conditioning circuit is connected to each conical antenna to convert the charge change characteristic signal into a voltage characteristic amplitude signal; one end of the shielded cable is connected to the front-end signal conditioning circuit of the electrostatic field sensor unit, and the other end is connected to the digital signal processing unit for transmitting the voltage characteristic amplitude signal converted by the front-end signal conditioning circuit of the electrostatic field sensor unit; the digital signal processing unit performs hardware filtering, digital sampling, and digital filtering processing on the voltage characteristic amplitude signal.

[0007] Preferably, the conical antenna is an axisymmetric electrostatic field induction electrode, and the total charge of each conical antenna includes the charge of the spherical portion and the charge of the conical portion.

[0008] Preferably, the aerial target charge telemetry system based on a conical antenna further includes a host computer connected to the digital signal processing unit, which receives the processed voltage amplitude characteristic signal transmitted by the digital signal processing unit, calculates the charge of the aerial target based on the target charge calculation mathematical model and the actual flight parameters of the aerial target, and displays it through the interface of the host computer.

[0009] The present invention also provides a method for telemetry of charge of an airborne target based on a conical antenna, comprising: step S1, obtaining the maximum voltage characteristic amplitude through an electrostatic field sensor unit; step S2, calculating the charge conversion coefficient K between the conical antenna and the airborne target; and step S3, obtaining the charge of the airborne target according to the target charge calculation formula.

[0010] Preferably, the charge conversion coefficient K = K in step S2 d ×K u K d K is the first conversion coefficient between the conical antenna and the external electric field E. u This is the second conversion coefficient between the electrostatic field sensor unit and the digital signal processing unit.

[0011] Preferably, under the action of an external electric field E, the first conversion coefficient K between the total flowing charge Q of the conical antenna and the external electric field E is... d The calculation formula is shown in equation (1):

[0012]

[0013] The total charge acquired by the conical antenna is composed of the charge Q of the conical portion. Sand the charge Q of the spherical part K The composition is calculated using the formula shown in equation (9):

[0014] Q = Q S +Q K (9)

[0015] in, Qs = q N q N This represents the charge value of the Nth equivalent charge.

[0016] Where N is the amount of equivalent charge on the cone-shaped antenna electrode axis, and the calculation formula is shown in equation (2):

[0017]

[0018] Where L1 = L-2·R-dm, L is the total length of the antenna, R is the radius of the spherical part, dm is the top diameter of the conical antenna, and dM is the bottom diameter of the conical antenna.

[0019] Preferably, the second conversion coefficient K u The feedback capacitor C in the electrostatic field sensor unit i The value of is determined, and the calculation formula is shown in equation (10):

[0020] K u =1 / C i (10).

[0021] Preferably, based on the maximum voltage amplitude of each conical antenna detected by the electrostatic field sensor unit in step S1, the estimated charge of each conical antenna is calculated, and the calculation formula is shown in equation (12):

[0022]

[0023] Among them, U im Let be the maximum voltage amplitude during the rendezvous between the airborne target and the conical antenna, K be the charge conversion coefficient, n0 be the unit normal vector, and ri(ti) be the time ti corresponding to the maximum voltage amplitude.

[0024] Preferably, the formula for calculating ri(ti) is as follows:

[0025]

[0026]

[0027] The flight parameters x0, v, H, and α in the formula for calculating ri(ti) are calculated by equation (11):

[0028]

[0029] Where x0 is the intersection of the projection of the flight trajectory onto the oxz plane and the ox axis; v is the flight speed of the aerial target; H is the flight altitude; and α is the angle between the projection of the flight trajectory onto the xoy plane and the y axis. Δt 12 The time difference Δt is used to obtain the maximum signal of the target electrostatic field for the first and second conical antennas, respectively. 13 The time difference between the first and third conical antennas acquiring the maximum signal of the target electrostatic field is ΔT1, which is the duration for the first conical antenna to receive the target electrostatic field signal.

[0030] Preferably, the charge of the airborne target is calculated using equation (13):

[0031]

[0032] Where, q i Let n be the estimated charge quantity corresponding to the i-th conical antenna, and n be the total number of conical antennas.

[0033] In summary, compared with existing technologies, the aerial target charge telemetry system and method based on a conical antenna provided by this invention, by employing an aerial target charge telemetry method based on a conical antenna, telemetry acquires the charge characteristic information of aerial flying targets during rendezvous. This allows for more flexible acquisition of the charge characteristics of aerial flying targets, providing test data for the charge characteristics of aerial targets and target detection and identification by electrostatic detection systems. Furthermore, this invention features flexible deployment of electric field sensors, unrestricted target flight paths, and high detection accuracy. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the operation of the aerial target charge telemetry system based on a conical antenna according to the present invention;

[0035] Figure 2 This is a schematic diagram of the mathematical model of the conical antenna of the present invention;

[0036] Figure 3 This is a mathematical model for telemetry of the charge quantity of an airborne target according to the present invention. Detailed Implementation

[0037] The following will be combined with the appendix in the embodiments of the present invention. Figure 1 ~Attached Figure 3 The technical solutions, structural features, objectives and effects achieved in the embodiments of the present invention will be described in detail.

[0038] It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions. They are only used to facilitate and clarify the purpose of illustrating the embodiments of the present invention, and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationship, or adjustments to the size should still fall within the scope of the technical content disclosed in the present invention, provided that they do not affect the effects and objectives that the present invention can produce.

[0039] It should be noted that, in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only the expressly listed elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0040] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the module connection of the aerial target charge telemetry system based on conical antennas according to the present invention. The system includes an electrostatic field sensor unit 1, a shielded cable 2, a digital signal processing unit 3, and a host computer 4. The electrostatic field sensor unit 1 includes at least three conical antennas 11 and a front-end signal conditioning circuit 12. Each conical antenna 11 senses and acquires the electrostatic field change characteristic information of an aerial flying target 5. The front-end signal conditioning circuit 12 is connected to the conical antennas 11 and converts the charge change characteristic signal into a voltage characteristic amplitude signal. One end of the shielded cable 2 is connected to the front-end signal conditioning circuit 12 of the electrostatic field sensor unit 1, and the other end is connected to the digital signal processing unit 3 for transmitting the voltage characteristic amplitude signal converted by the front-end signal conditioning circuit 12 of the electrostatic field sensor unit 1. The digital signal processing unit 3 performs hardware filtering, digital sampling, and digital filtering on the voltage characteristic amplitude signal, and the host computer 4 stores and displays the real-time test data processed by the digital signal processing unit 3.

[0041] Furthermore, the conical antenna 11, based on the electrostatic field induction mechanism, achieves the sensing and acquisition of the charge of the airborne target 5. For example... Figure 2 As shown, the conical antenna 11 is an axisymmetric electrostatic field induction electrode, which has the advantage of relatively simple calculation of the conversion coefficient. The total charge of each conical antenna 11 includes the charge of the spherical part 111 and the charge of the conical part 112. The total charge and conversion coefficient are calculated using a mathematical model.

[0042] like Figure 1As shown, in this embodiment, the electrostatic field sensor unit 1 is equipped with three conical antennas 11, namely a first conical antenna, a second conical antenna, and a third conical antenna, to form an electrostatic sensor array. The first, second, and third conical antennas are all arranged on the xoy plane of the Cartesian coordinate system (arranged on the ox and oy axes respectively, e.g., ...). Figure 3 As shown in the figure, it is used to sense and acquire changes in the electrostatic field of the airborne target 5.

[0043] The front-end signal conditioning circuit 12 in the electrostatic field sensor unit 1, based on charge sensitivity conversion technology, converts the induced charge signal acquired by each conical antenna 11 into a voltage amplitude characteristic signal. Simultaneously, the high-pass filter unit in the front-end signal conditioning circuit 12 suppresses low-frequency electric field interference signals, improving the sensitivity of charge detection. The shielded cable 2 connects the front-end signal conditioning circuit 12 and the digital signal processing unit 3, respectively, to reduce interference from the natural environment and the test system on the conical antenna 11, ensuring high-quality transmission of the voltage amplitude characteristic signal.

[0044] Furthermore, the digital signal processing unit 3 receives the voltage amplitude characteristic signal transmitted by the shielded cable 2, performs hardware low-pass filtering, sampling, digital band-pass filtering, and low-frequency suppression signal compensation on the voltage amplitude characteristic signal in sequence, and transmits the processed voltage amplitude characteristic signal to the host computer 4 through the communication chip in the digital signal processing unit 3.

[0045] Furthermore, the host computer 4 is used to receive the processed voltage amplitude characteristic signal transmitted by the digital signal processing unit 3, calculate the charge of the airborne target 5 based on the target charge calculation mathematical model and according to the actual flight parameters of the airborne target 5, and display it through the interface of the host computer 4.

[0046] The present invention also provides a method for telemetry of the charge of an airborne target based on a conical antenna, comprising:

[0047] Step S1: Obtain the maximum voltage characteristic amplitude through electrostatic field sensor unit 1;

[0048] Step S2: Calculate the charge conversion coefficient K between the conical antenna 11 and the airborne target 5;

[0049] Step S3: Obtain the charge of the airborne target 5 according to the target charge calculation formula.

[0050] In step S1, the maximum voltage characteristic amplitude is selected from the voltage characteristic amplitudes corresponding to the three conical antennas 11 in the electrostatic field sensor unit 1.

[0051] Wherein, the charge conversion coefficient K = K in step S2 d×K u K d K is the first conversion coefficient between the conical antenna 11 and the external electric field E (i.e., the electric field formed by the airborne target 5). u This is the second conversion coefficient between the electrostatic field sensor unit 1 and the digital signal processing unit 3.

[0052] Specifically, refer to Figure 2 Under the influence of an external electric field E, the charge on the surface of the conical antenna 11 is redistributed. The first conversion coefficient K between the total flowing charge Q of the conical antenna 11 and the external electric field E... d The calculation formula is shown in equation (1):

[0053]

[0054] Due to the axial symmetry of the conical antenna 11, the charge on the electrode surface (i.e., the surface of the conical antenna 11) is calculated using the equivalent charge method. The positions of the Z-axis and X-axis in the rectangular coordinate system are as follows: Figure 2 As shown, for each point charge at coordinate zi, it is associated with a point on the surface zj of the conical antenna 11, and the values ​​of variables i and j range from 0 to N; where N is the number of equivalent charges on the electrode axis of the conical part 112 of the conical antenna 11, and the calculation formula is shown in equation (2):

[0055]

[0056] in,

[0057] L1 = L-2·R-dm, L is the total length of the antenna, R is the radius of the spherical part, dm is the top diameter of the conical antenna, and dM is the bottom diameter of the conical antenna.

[0058] like Figure 2 As shown, the coordinates of the center point charge (xi, zi) and the coordinates of the surface point charge (xj, zj) of the conical antenna are expressed by geometric parameters as shown in equations (3) to (6):

[0059] x i =0(3)

[0060]

[0061]

[0062]

[0063] Let ri represent the vector radius of the i-th point charge, and r1j be the vector radius of the j-th point on the surface. The electric potential at the j-th point on the surface by the i-th point charge and its equivalent charge is calculated, and the calculated electric potential is used to calculate the total charge q, as shown in equation (7):

[0064]

[0065] The system of algebraic equations for the target unknown charge qi is expressed in matrix form (8) as follows:

[0066] q = P -1 ·E·Z j (8)

[0067] Where P is a matrix with coefficients, E is the external electric field value, and Zj is the coordinate of the surface point charge.

[0068] The total charge obtained by the conical antenna 11 is the charge Q of the conical portion 112. S and the charge Q of the spherical part 111 K The composition is calculated using the formula shown in equation (9):

[0069] Q = Q S +Q K (9)

[0070] in, Qs = q N q N Let N be the charge value of the Nth equivalent charge.

[0071] Specifically, the second conversion coefficient K u The feedback capacitor C in electrostatic field sensor unit 1 i The value is determined in this embodiment by calculating the second conversion coefficient K from the charge Q of the electrostatic field sensor unit 1 to the output voltage U1 of the amplifier in the digital signal processing unit 3. u The calculation formula is shown in equation (10):

[0072] K u =U1 / Q=1 / C i (10)

[0073] This embodiment provides a specific example of calculating the charge of the conical antenna 11. If the external electric field E = 100V / m, the relevant calculation parameters of the conical antenna 11 for the charge calculation of the airborne target 5 are shown in Table 1. Based on equation (2), according to the values ​​of L, R, and dm in Table 1, the value of the equivalent charge N on the electrode axis of the conical part 112 of the conical antenna 11 can be obtained.

[0074] Table 1. Parameter values ​​of the conical antenna

[0075] Parameter, unit Value L, m 1 R, mm 4 dm, mm 2 dM, mm 8 Q·10 -9 , C]] -5.97 Q K ·10 -9 , C]] -5.6 Q S ·10 -9 , C]] -0.37 K d ·10 -11 , C·m / V]]> -5.97

[0076] refer to Figure 3 The conical antenna 11 includes three conical antennas 11, namely a first conical antenna, a second conical antenna, and a third conical antenna. In this embodiment, the position point of the first conical antenna is (0, 0, 0), the position point of the second conical antenna is (0, y2, 0), and the position point of the third conical antenna is (x3, 0, 0). Based on the target static charge telemetry mathematical model, according to the charge obtained by different conical antennas 11, the corresponding voltage amplitude information is obtained by the digital signal processing unit 3, and the charge of the airborne target 5 is calculated.

[0077] Based on the theory of calculating the maximum and minimum values ​​and inflection points of the intersection signal between the airborne target 5 and the electrostatic field sensor unit 1, the flight parameters of the airborne target 5 (such as...) can be calculated. Figure 3 As shown in the figure), the mathematical calculation formula is as shown in equation (11):

[0078]

[0079] Where x0 is the intersection of the projection of the flight trajectory onto the oxz plane and the ox axis; v is the flight speed of the aerial target; H is the flight altitude; and α is the angle between the projection of the flight trajectory onto the xoy plane and the y axis. Δt 12 The time difference Δt is used to obtain the maximum signal of the target electrostatic field for the first and second conical antennas, respectively. 13 The time difference between the first and third conical antennas acquiring the maximum signal of the target electrostatic field is ΔT1, which is the duration for the first conical antenna to receive the target electrostatic field signal.

[0080] Based on the maximum voltage characteristic amplitude detected by the electrostatic field sensor unit array (composed of multiple different conical antennas 11) in step S1, the estimated charge quantity corresponding to each conical antenna 11 is calculated, and the calculation formula is shown in equation (12):

[0081]

[0082] Among them, U im The maximum voltage characteristic amplitude during the intersection of the airborne target 5 and the conical antenna 11 is obtained by the digital signal processing unit 3, that is, the corresponding voltage amplitude information is obtained; K is the charge conversion coefficient; n0 is the unit normal vector; ri(ti) is the time ti corresponding to the maximum value of the signal. The vector between the electrostatic field sensor and the target is calculated by equation (11).

[0083] The formula for calculating ri(ti) is as follows:

[0084]

[0085]

[0086] Therefore, the charge of the airborne target 5 is calculated using equation (13):

[0087]

[0088] Where, q i Let n be the estimated charge quantity corresponding to the i-th conical antenna 11, and n be the total number of conical antennas 11.

[0089] In summary, compared with the prior art, the system and method for telemetry of airborne target charge based on a conical antenna provided by this invention can more flexibly acquire the charge characteristics of airborne targets, providing test data for the charge characteristics of airborne targets and target detection and identification of electrostatic detection systems, and has good application prospects.

[0090] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A method for telemetry of the charge of an airborne target based on a conical antenna, characterized in that, include: Step S1: Obtain the maximum voltage characteristic amplitude through the electrostatic field sensor unit (1); Step S2: Calculate the charge conversion coefficient K between the conical antenna (11) and the airborne target (5); Step S3: Obtain the charge of the airborne target (5) according to the target charge calculation formula; Among them, the charge conversion coefficient mentioned in step S2 , The first conversion coefficient between the conical antenna (11) and the external electric field E is given. This is the second conversion coefficient between the electrostatic field sensor unit (1) and the digital signal processing unit (3); Under the action of an external electric field E, the first conversion coefficient between the total flowing charge Q of the conical antenna (11) and the external electric field E is... The calculation formula is shown in equation (1): （1）； The total charge obtained by the conical antenna (11) is derived from the charge of the conical portion (112). and the charge of the spherical part (111) The composition is calculated using the formula shown in equation (9): （9） in, , q N Let N be the charge value of the Nth equivalent charge; Where N is the amount of equivalent charge on the electrode axis of the conical part (112) of the conical antenna (11), and the calculation formula is shown in equation (2): （2） in, , L is the total length of the antenna, R is the radius of the spherical part, dm is the diameter of the top of the conical antenna, and dM is the diameter of the bottom of the conical antenna. Second conversion coefficient The feedback capacitor in the electrostatic field sensor unit (1) The value of is determined, and the calculation formula is shown in equation (10): （10）； Based on the maximum voltage amplitude of each conical antenna (11) detected by the electrostatic field sensor unit (1) in step S1, the estimated charge of each conical antenna (11) is calculated, and the calculation formula is shown in equation (12): （12） in, The maximum voltage amplitude during the rendezvous between the airborne target (5) and the conical antenna (11) is given by K, which is the charge conversion coefficient; n0 is the unit normal vector; and ri (ti) is the time ti corresponding to the maximum voltage amplitude. The charge of the airborne target (5) is calculated using equation (13): in, For the first The estimated charge quantity corresponding to each conical antenna (11) This represents the total number of conical antennas (11).

2. The method for telemetry of airborne target charge based on a conical antenna as described in claim 1, characterized in that, The formula for calculating ri(ti) is as follows: , , , ； The flight parameters in the formula for calculating ri(ti) , , , Calculated using equation (11): （11） in, The point where the projection of the flight trajectory onto the oxz plane of the coordinate system intersects the ox axis; The speed of flight of aerial targets; Flight altitude; Let be the angle between the projection of the trajectory onto the xoy plane and the y-axis; The time difference for the first and second conical antennas to acquire the maximum signal of the target electrostatic field, respectively; The time difference for the first and third conical antennas to acquire the maximum signal of the target electrostatic field, respectively; The duration of the target electrostatic field signal received by the first conical antenna.

3. An airborne target charge telemetry system based on a conical antenna, used to implement the airborne target charge telemetry method based on a conical antenna as described in claim 1 or 2, characterized in that, include: Electrostatic field sensor unit (1), shielded cable (2), digital signal processing unit (3); The electrostatic field sensor unit (1) includes at least three conical antennas (11) and a front-end signal conditioning circuit (12); each conical antenna (11) senses and acquires the electrostatic field change characteristics of the airborne target (5); the front-end signal conditioning circuit (12) is connected to the conical antennas (11) respectively, and converts the charge change characteristic signal into a voltage characteristic amplitude signal; One end of the shielded cable (2) is connected to the front-end signal conditioning circuit (12) of the electrostatic field sensor unit (1), and the other end is connected to the digital signal processing unit (3) for transmitting the voltage characteristic amplitude signal converted by the front-end signal conditioning circuit (12) of the electrostatic field sensor unit (1). The digital signal processing unit (3) performs hardware filtering, digital sampling, and digital filtering on the voltage characteristic amplitude signal.

4. The airborne target charge telemetry system based on a conical antenna as described in claim 3, characterized in that, The conical antenna (11) is an axisymmetric electrostatic field induction electrode, and the total charge of each conical antenna (11) includes the charge of the spherical part (111) and the charge of the conical part (112).

5. The airborne target charge telemetry system based on a conical antenna as described in claim 3, characterized in that, It also includes a host computer (4), which is connected to the digital signal processing unit (3), receives the processed voltage amplitude characteristic signal transmitted by the digital signal processing unit (3), calculates the charge of the air-flying target (5) based on the target charge calculation mathematical model and according to the actual flight parameters of the air-flying target (5), and displays it through the interface of the host computer (4).

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