An online measurement device and method for network impedance matching

Abstract

This invention discloses a network impedance matching measurement device and method. The device includes: a current detection circuit with a current sampling terminal and a current output terminal, wherein the current sampling terminal is mutually inducted with the transmitter transmission line, and the current output terminal outputs a current value; a voltage detection circuit with a voltage sampling terminal and a voltage output terminal, wherein the voltage sampling terminal is connected to any point on the transmitter transmission line, and the voltage output terminal outputs a voltage value; and a controller with a current input terminal, a voltage input terminal, and an impedance output terminal, wherein the current input terminal is connected to the current output terminal, and the voltage output terminal is connected to the voltage input terminal. The controller is used to obtain the impedance value Z based on the current and voltage values. mi And based on the pre-stored conversion function F(Z) mi b) Output the network impedance value, thereby realizing online measurement of network impedance. Online measurement of network impedance avoids transmitter shutdown and is highly practical.

Description

Technical Field

[0001] This invention relates to the field of transmitter technology, and more particularly to an online measurement device and method for network impedance matching. Background Technology

[0002] As is well known, impedance matching is a crucial technical specification for medium-wave transmitters, and impedance measurement is a prerequisite for impedance matching. Currently, impedance measurement is generally performed offline. Offline measurement requires shutting down the transmitter before connecting it to a network analyzer for measurement. This not only affects the normal operation of the transmitter but also has poor practicality. Summary of the Invention

[0003] This invention provides an online network impedance matching measurement device and method to achieve online measurement of network impedance. Online network impedance measurement avoids transmitter shutdown and is highly practical.

[0004] To achieve the above objectives, one embodiment of the present invention provides an online network impedance matching measurement device, comprising:

[0005] A current detection circuit includes a current sampling terminal and a current output terminal. The current sampling terminal is mutually inducted with the inductance of the transmitter transmission line, and the current output terminal is used to output the current value.

[0006] A voltage detection circuit includes a voltage sampling terminal and a voltage output terminal. The voltage sampling terminal is connected to any point on the transmitter transmission line, and the voltage output terminal is used to output a voltage value.

[0007] The controller includes a current input terminal, a voltage input terminal, and an impedance output terminal. The current input terminal is connected to the current output terminal, and the voltage output terminal is connected to the voltage input terminal. The controller is used to obtain the impedance value Z based on the current value and the voltage value. mi And based on the pre-stored conversion function F(Z) mi b) Output network impedance value.

[0008] Optionally, the current detection circuit includes: a first inductor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a first diode, a second diode, a third capacitor, and a fourth capacitor;

[0009] The first inductor, the first capacitor, the second capacitor, the first resistor, and the second resistor are connected in parallel to form a first parallel circuit, and the first inductor is mutually inducted with the inductance of the transmitter transmission line; the third resistor and the fourth resistor are connected in series and then in parallel with the first parallel circuit to form a second parallel circuit; one end of the fifth resistor is connected to one end of the second parallel circuit, and the other end of the fifth resistor is connected to the anode of the first diode; one end of the sixth resistor is connected to the other end of the second parallel circuit, and the other end of the sixth resistor is connected to the anode of the second diode; the seventh resistor and the third capacitor are connected in parallel to form a third parallel circuit, and the eighth resistor and the fourth capacitor are connected in parallel to form a fourth parallel circuit. One end of the third parallel circuit is connected to the anode of the first diode, one end of the fourth parallel circuit is connected to the anode of the second diode, and the other end of the third parallel circuit is connected to the other end of the fourth parallel circuit.

[0010] Optionally, the voltage detection circuit includes: a second inductor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, and an eleventh capacitor; the sixth capacitor and the seventh capacitor are connected in parallel to form a fifth parallel circuit; one end of the fifth capacitor is connected to the transmitter transmission line, and the other end of the fifth capacitor is connected to one end of the fifth parallel circuit, the other end of the fifth parallel circuit is grounded; one end of the eighth capacitor is connected to one end of the fifth parallel circuit, and the other end of the eighth capacitor is grounded; one end of the ninth capacitor is connected to one end of the fifth parallel circuit, and the other end of the ninth capacitor is grounded; one end of the tenth capacitor is connected to one end of the fifth parallel circuit, and the other end of the tenth capacitor is grounded; one end of the eleventh capacitor is connected to one end of the fifth parallel circuit, and the other end of the eleventh capacitor is grounded; one end of the second inductor is connected to one end of the fifth parallel circuit, and the other end of the second inductor is grounded; one end of the second inductor is also connected between the third resistor and the fourth resistor.

[0011] Optionally, the online network impedance matching measurement device further includes: an analog-to-digital converter (ADC), wherein the current input terminal of the ADC is connected to the negative terminal of the first diode, and the voltage input terminal of the ADC is connected to the other end of the fifth capacitor; the current output terminal of the ADC is connected to the current value input terminal of the controller, and the voltage output terminal of the ADC is connected to the voltage input terminal of the controller.

[0012] To achieve the above objectives, another embodiment of the present invention proposes an online method for measuring network impedance matching, comprising the following steps:

[0013] Obtain the current and voltage of the transmitter transmission line;

[0014] The impedance value Z is obtained based on the current and voltage of the transmitter transmission line. mi And according to the transformation function F(Z) mi b) Obtain the impedance value of the transmitter antenna.

[0015] Optionally, the network impedance matching measurement method further includes the following steps:

[0016] The transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) are, where,

[0017] F(Z mi b) = (Z mi -b2) / (b1-Z mi *b3).

[0018] Optionally, the step of estimating the transformation function F(Z) using the adaptive weighted least squares method... mi The complex coefficients b1, b2, and b3 in b) include the following steps:

[0019] Obtain the i sets of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value;

[0020] Obtain the impedance value Z of the i-th set of online measurement terminals of the network. mi This is denoted as the second impedance value, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i sets of online measured impedance values ​​Z of the network. i This is denoted as the third impedance value;

[0021] Obtain the coordinate distance between the first impedance value and the target impedance value in each group, and denote it as the first distance R. i ;

[0022] According to the first distance R i Construct the weight function W(R) i ′);

[0023] Obtain the coordinate distance between the first impedance value and the third impedance value in each group, and denote it as the second distance;

[0024] Based on the adaptive weighted least squares method, the weight function W(R) i ′) and the second distance constructs the error function E(b); where,

[0025]

[0026] Based on numerical calculations and nonlinear regression methods, the equation E(b)=∑ i W(R′ i )|Z ni -F(Z mi b)| 2 Estimate the value of parameter b and solve for it.

[0027] Optionally, the step of estimating the transformation function F(Z) using the adaptive weighted least squares method... mi The complex coefficients b1, b2, and b3 in b) include the following steps:

[0028] Obtain the i sets of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value;

[0029] Obtain the impedance value Z of group i online measurement terminals. mi This is denoted as the second impedance value, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i sets of online measured impedance values ​​Z of the network. i This is denoted as the third impedance value;

[0030] Obtain the coordinate distance between the first impedance value and the target impedance value in each group, and denote it as the first distance R. i ;

[0031] According to the first distance R i Construct the weight function W(R) i ′);

[0032] F(Z) will be obtained using the adaptive weighted least squares method. mi The matrix form of b):

[0033]

[0034] Taking the derivative of B with respect to H(B), the solution is found when the derivative is 0.

[0035] B = (X) T WX) -1 X T WY.

[0036] Specifically, the weighting function W(R) i ′) is R i A decreasing function, where R i ′=R i / R max R max This is the maximum distance between the first impedance value and the target impedance value.

[0037] Optionally, the decreasing function is:

[0038]

[0039] or

[0040]

[0041] Where g > 0; h > 0; 0 < R i ′<1.

[0042] This invention proposes an online impedance matching measurement device and method for networks. The device includes: a current detection circuit with a current sampling terminal and a current output terminal, wherein the current sampling terminal is mutually inducted with the inductance of the transmitter transmission line, and the current output terminal outputs a current value; a voltage detection circuit with a voltage sampling terminal and a voltage output terminal, wherein the voltage sampling terminal is connected to any point on the transmitter transmission line, and the voltage output terminal outputs a voltage value; and a controller with a current input terminal, a voltage input terminal, and an impedance output terminal, wherein the current input terminal is connected to the current output terminal, and the voltage output terminal is connected to the voltage input terminal. The controller is used to obtain an impedance value Z based on the current value and the voltage value. mi And based on the pre-stored conversion function F(Z) mi b) Output the network impedance value, thereby realizing online measurement of network impedance. Online measurement of network impedance avoids transmitter shutdown and is highly practical. Attached Figure Description

[0043] Figure 1 This is a block diagram of the online network impedance matching measurement device proposed in an embodiment of the present invention;

[0044] Figure 2 This is a circuit diagram of the current detection circuit and voltage detection circuit in the online network impedance matching measurement device proposed in this embodiment of the invention;

[0045] Figure 3 This is a block diagram of an online network impedance matching measurement device proposed in another embodiment of the present invention;

[0046] Figure 4 This is a flowchart of the online network impedance matching measurement method proposed in this embodiment of the invention;

[0047] Figure 5 This is a flowchart of an online network impedance matching measurement method proposed in one embodiment of the present invention;

[0048] Figure 6 This is a flowchart of an online network impedance matching measurement method proposed in another embodiment of the present invention;

[0049] Figure 7This is a flowchart of an online measurement method for network impedance matching proposed in another embodiment of the present invention. Detailed Implementation

[0050] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0051] Figure 1 This is a block diagram of the online network impedance matching measurement device proposed in an embodiment of the present invention. Figure 1 As shown, the online impedance matching measurement device 100 includes:

[0052] The current detection circuit 101 includes a current sampling terminal 101a and a current output terminal 101b. The current sampling terminal 101a is mutually inducted with the inductance L1 of the transmitter transmission line, and the current output terminal 101b is used to output the current value.

[0053] The voltage detection circuit 102 includes a voltage sampling terminal 102a and a voltage output terminal 102b. The voltage sampling terminal 102a is connected to any point on the transmitter transmission line, and the voltage output terminal 102b is used to output the voltage value.

[0054] Controller 103 includes a current input terminal 103a, a voltage input terminal 103b, and an impedance output terminal 103c. The current input terminal 103a is connected to the current output terminal 101b, and the voltage output terminal 102b is connected to the voltage input terminal 103b. The controller is used to obtain the impedance value Z based on the current and voltage values. mi And based on the pre-stored conversion function F(Z) mi b) Output network impedance value.

[0055] In other words, the current sampling terminal 101a of the current detection circuit 101 is mutually inducted with the inductance L1 of the transmitter transmission line, and the current output terminal 101b is connected to the current value input terminal 103a of the controller 103. Similarly, the voltage sampling terminal 102a of the voltage detection circuit 102 is connected to any point on the transmitter transmission line, and the voltage output terminal 102b is connected to the voltage value input terminal 103b of the controller 103. The controller 103 calculates an impedance value based on the current input terminal 103a and the voltage input terminal 103b, and then uses a pre-stored conversion function F(Z) to perform the calculation. mi b) Output the network impedance value. Therefore, the transmitter impedance matching measurement device 100 can realize online measurement of network impedance, avoiding transmitter downtime and demonstrating strong practicality.

[0056] Figure 2 This is a circuit diagram of the current detection circuit and voltage detection circuit in the online network impedance matching measurement device proposed in an embodiment of the present invention. Optionally, as shown... Figure 2 As shown, the current detection circuit 101 includes: a first inductor L2, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a first diode D1, a second diode D2, a third capacitor C3, and a fourth capacitor C4.

[0057] The first inductor L2, the first capacitor C1, the second capacitor C2, the first resistor R1, and the second resistor R2 are connected in parallel to form a first parallel circuit. The first inductor L2 is mutually inducted with the inductance L1 of the transmitter transmission line. The third resistor R3 and the fourth resistor R4 are connected in series and then in parallel with the first parallel circuit to form a second parallel circuit. One end of the fifth resistor R5 is connected to one end of the second parallel circuit, and the other end of the fifth resistor R5 is connected to the anode of the first diode D1. One end of the sixth resistor R6 is connected to the other end of the second parallel circuit, and the other end of the sixth resistor R6 is connected to the anode of the second diode D2. The seventh resistor R7 and the third capacitor C3 are connected in parallel to form a third parallel circuit. The eighth resistor R8 and the fourth capacitor C4 are connected in parallel to form a fourth parallel circuit. One end of the third parallel circuit is connected to the anode of the first diode D1, and one end of the fourth parallel circuit is connected to the anode of the second diode D2. The other ends of the third parallel circuit and the other ends of the fourth parallel circuit are connected.

[0058] Figure 2 This is a circuit diagram of the current detection circuit and voltage detection circuit in the online network impedance matching measurement device proposed in an embodiment of the present invention. Optionally, as shown... Figure 2As shown, the voltage detection circuit 102 includes: a second inductor L3, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, a tenth capacitor C10, and an eleventh capacitor C11; the sixth capacitor C6 and the seventh capacitor C7 are connected in parallel to form a fifth parallel circuit; one end of the fifth capacitor C5 is connected to the transmitter transmission line, and the other end of the fifth capacitor C5 is connected to one end of the fifth parallel circuit, the other end of the fifth parallel circuit is grounded to GND; one end of the eighth capacitor C8 is connected to one end of the fifth parallel circuit, and the other end of the eighth capacitor C8 is grounded to GN. D. One end of the ninth capacitor C9 is connected to one end of the fifth parallel circuit, and the other end of the ninth capacitor C9 is grounded to GND. One end of the tenth capacitor C10 is connected to one end of the fifth parallel circuit, and the other end of the tenth capacitor C10 is grounded to GND. One end of the eleventh capacitor C11 is connected to one end of the fifth parallel circuit, and the other end of the eleventh capacitor C11 is grounded to GND. One end of the second inductor L3 is connected to one end of the fifth parallel circuit, and the other end of the second inductor L3 is grounded to GND. One end of the second inductor L3 is also connected to point B between the third resistor R3 and the fourth resistor R4.

[0059] In the current detection circuit 101, the first inductor L2 is inductively coupled to the transmitter transmission line inductor L1 to obtain the current of the transmitter transmission line. In the voltage detection circuit 102, one end of the fifth capacitor C5 is connected to point A of the transmitter transmission line, and the other end is the voltage output terminal 102b to obtain the voltage of the transmitter transmission line.

[0060] Among them, the fifth resistor R5 is connected in series with the first diode D1, the sixth resistor is connected in series with the second diode D2, and both serve as detectors; the seventh resistor R7 is connected in parallel with the third capacitor C3, and the eighth resistor R8 is connected in parallel with the fourth capacitor C4, and both serve as filters.

[0061] The controller 103 obtains an impedance based on the output current of the current detection circuit 101 and the output voltage of the voltage detection circuit 102, and then uses the conversion function F(Z) to determine the impedance. mi b) Output network impedance value.

[0062] Voltage can be acquired using any method that directly or indirectly obtains voltage. Current can be acquired using any method that directly or indirectly obtains current.

[0063] Figure 3 This is a block diagram of an online network impedance matching measurement device according to another embodiment of the present invention. Optionally, as shown... Figure 3As shown, the online network impedance matching measurement device 100 further includes: an analog-to-digital converter 104, the current input terminal of the analog-to-digital converter 104 is connected to the negative terminal of the first diode D1, the voltage input terminal of the analog-to-digital converter 104 is connected to the other end of the fifth capacitor C5; the current output terminal of the analog-to-digital converter 104 is connected to the current value input terminal 103a of the controller 103, and the voltage output terminal of the analog-to-digital converter 104 is connected to the voltage input terminal 103b of the controller 103.

[0064] It should be noted that, Figure 1 as well as Figure 3 The arrows in the diagram only indicate the direction of signal transmission.

[0065] The current detection circuit 101 acquires an analog value for the current, and the voltage detection circuit 102 acquires an analog value for the voltage. Therefore, the analog-to-digital converter converts the current acquired by the current detection circuit 101 into a digital current signal and the voltage acquired by the voltage detection circuit 102 into a digital voltage signal, which facilitates the subsequent calculations by the controller 103.

[0066] Therefore, the controller 103 obtains an impedance based on the output current of the current detection circuit 101 and the output voltage of the voltage detection circuit 102, and then uses the conversion function F(Z) to determine the impedance. mi (b) Output the network impedance value. This allows staff to adjust the values ​​of capacitors, inductors, or resistors in the entire matching network based on the network impedance value, making the impedance of the entire matching network closer and closer to the matching target (50 ohms). The more measurements are taken, the more accurate the results become, and the better the adjustments are made.

[0067] Figure 4 This is a flowchart of the online network impedance matching measurement method proposed in an embodiment of the present invention. Figure 4 As shown, the online measurement method for network impedance matching includes the following steps:

[0068] S101, obtain the current of the transmitter transmission line;

[0069] S102, Obtain the voltage of the transmitter transmission line;

[0070] S103, Obtain the impedance value Z based on the current and voltage of the transmitter transmission line. mi And according to the transformation function F(Z) mi b) Obtain the impedance value of the transmitter antenna.

[0071] In other words, obtain the current in the transmitter transmission line; obtain the voltage in the transmitter transmission line; obtain an impedance based on the current and voltage; and then apply the transformation function F(Z) to the impedance. mi(b) Output network impedance value. This enables online measurement of the network impedance, avoiding transmitter downtime and offering high practicality. Furthermore, it allows operators to adjust the values ​​of capacitors, inductors, or resistors in the entire matching network based on the transmitter impedance value, making the impedance of the entire matching network increasingly closer to the target impedance value (50 ohms). The more measurements are performed, the better the results become.

[0072] Figure 5 This is a flowchart of an online network impedance matching measurement method according to an embodiment of the present invention. Optionally, as... Figure 5 As shown, the online measurement method for network impedance matching also includes the following steps:

[0073] S100, the transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) are, where,

[0074] F(Z mi b) = (Z mi -b2) / (b1-Z mi *b3).

[0075] It is understandable that the above transformation function F(Z) mi b) is a four-port model. The impedance values ​​obtained from online current and voltage measurements do not represent the network impedance; they need to be converted using a four-port model to obtain the network impedance. Therefore, the conversion function F(Z) needs to be tested and obtained in advance. mi The coefficients b1, b2, and b3 in b) are measured using the following methods:

[0076] Figure 6 This is a flowchart of an online network impedance matching measurement method proposed in another embodiment of the present invention. Optionally, as... Figure 6 As shown, step S100 includes estimating the transformation function F(Z) using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) include the following steps:

[0077] S1001, Obtain the i-th set of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value;

[0078] Among them, the offline measured impedance value Z ni To measure the known network impedance using a network analyzer after the transmitter has been shut down.

[0079] S1002, Obtain the impedance value Z of the i-th group of online measurement terminals of the network. mi This is denoted as the second impedance value;

[0080] Impedance value Z at the online measurement terminalmi The impedance is the voltage and current measured online without shutting down the transmitter.

[0081] S1003, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i-th set of online measured impedance values ​​Z of the network. i This is denoted as the third impedance value;

[0082] Among them, the online measured impedance value Z i The impedance value Z at the online measurement terminal mi Through the transformation function F(Z) mi b) The converted value is obtained by online measurement of impedance value Z. It should be noted that during the conversion, the impedance value Z is measured online. i The impedance value Z at the online measurement terminal mi An expression carrying parameter b.

[0083] Each time a first impedance value is acquired, a set of second impedance values ​​is acquired, and the second impedance value is converted into a third impedance value. The first impedance value, the second impedance value, and the third impedance value are a set.

[0084] S1004, Obtain the coordinate distance between the first impedance value and the target impedance value in each group, denoted as the first distance R. i ;

[0085] It is understandable that the target impedance value is 50 ohms, and the coordinate distance between the first impedance value and the target impedance value is the square of the magnitude between the first impedance value and the target impedance value.

[0086] S1005, based on the first distance R i Construct the weight function W(R) i ′);

[0087] Wherein, the first distance R i The larger the value, the greater the weight function W(R) i The smaller the weight of ′), that is, the farther the first impedance value is from the target impedance value after the first impedance value is obtained, the smaller the weight is.

[0088] Specifically, the weighting function W(R) i ′) is R i A decreasing function, where R i ′=R i / R max R max This represents the maximum distance between the first impedance value and the target impedance value. Let Z... ni Using the real and imaginary parts as the x and y coordinates respectively, calculate the distance R between it and 50 ohms (50+0j). iDefine W(R) as the weight function. W(R) is a decreasing function of R. When R1 > R2, W(R1) < W(R2), and W(R) > 0. Define the normalized distance R. i '=R i / R max 0≤R i '≤1, i=1, 2,...,K.

[0089] The adaptive weight function W can be any decreasing function. For example, it can (but is not limited to) be:

[0090]

[0091] or

[0092]

[0093] Where g > 0; h > 0; 0 < R i ′<1.

[0094] S1006, Obtain the coordinate distance between the first impedance value and the third impedance value in each group, and record it as the second distance;

[0095] The coordinate distance between the first impedance value and the third impedance value is the square of the magnitude between them.

[0096] S1007, based on the adaptive weighted least squares method and the weight function W(R) i The second distance constructs the error function E(b); where,

[0097] E(b)=∑ i W(R′ i )|Z ni -F(Z mi b)| 2 .

[0098] It is understandable that the weight function W(R) i As the magnitude between the first impedance value and the target impedance value increases, the weight decreases. The square of the magnitude between the third impedance value and the first impedance value represents the distance between the online measurement value and the offline measurement value, while the offline measurement value represents the true impedance of the network. The weight function is multiplied by the square of the magnitude between the third impedance value and the first impedance value to form the error function. This ensures that during the error calculation process, most of the weight is distributed near the values ​​where the first impedance value and the target impedance value are close. At the same time, based on this part of the weight, the error between the first impedance value and the third impedance value corresponding to this part of the weight distribution also accounts for most of the weight. Thus, it ensures that samples closer to the 50-ohm matching point have higher weight values, thereby improving the calibration accuracy of key areas near 50 ohms.

[0099] S1008, based on numerical calculation of the nonlinear regression method, the equation E(b)=∑ i W(R′ i )|Z ni -F(Z mi b)| 2 Estimate the value of parameter b. Generally, at least six sets of data are required for the calculation. Nonlinear regression is performed using the Levenberg-Marquardt method.

[0100] The values ​​of b are calculated as follows: b1 = -0.0225 + 0.0185i; b2 = -0.9122 + 0.2588i; b3 = -0.0629 - 0.0105i.

[0101] Table 1 shows the measured first and second impedance values, as well as the calculated sets of third impedance values.

[0102] Zm Zn F(Zm, b) 0.5582-0.8238i 52.0000+14.3000i 50.5821+14.4154i 0.5201-0.8113i 53.5000+17.0000i 51.4950+17.3039i 0.8024-0.6919i 50.0000-3.0000i 50.2434-3.3046i 0.8572-0.6433i 48.5000-7.0000i 48.7740-7.0563i 0.9156-0.5724i 46.3000-12.5000i 46.6546-11.2542i 0.9635-0.4818i 45.0000-18.0000i 44.0822-15.4206i 0.9998-0.3454i 43.0000-25.0000i 40.1024-20.3394i

[0103] After calculating the b-value, the impedance of the matching network can be adjusted based on the online measured current and voltage and the transfer function. As the impedance network is gradually adjusted, the error in the calibrated measurement results decreases, and the actual impedance value gets closer to 50 ohms (the target impedance value). Meanwhile, the impedance properties (capacitive, inductive) in other non-critical areas remain unchanged. In practical applications, for example, if the initial impedance is found to be capacitive, there is no need to focus on the specific error value; simply adjust the network towards inductive impedance. With each adjustment, the impedance gets closer to 50 ohms, and the measurement error decreases, thus gradually approaching the 50-ohm matching point.

[0104] Figure 7 This is a flowchart of an online network impedance matching measurement method according to another embodiment of the present invention. Optionally, as shown... Figure 7 As shown, the transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) include the following steps:

[0105] S2001, Obtain the i-th set of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value;

[0106] S2002, Obtain the impedance value Z of the i-th group of online measurement terminals. mi This is denoted as the second impedance value;

[0107] S2003, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i-th set of online measured impedance values ​​Z of the network. iThis is denoted as the third impedance value;

[0108] S2004, Obtain the coordinate distance between the first impedance value and the target impedance value in each group, denoted as the first distance R. i ;

[0109] S2005, based on the first distance R i Construct the weight function W(R) i ′);

[0110] S2006, according to the adaptive weighted least squares method, F(Z) will be obtained. mi The matrix form of b):

[0111] Let F(Z) mi b) = Z ni ;

[0112] Obtain the relation Z ni *b1+b2-Z ni *Z mi *b3=Z mi ;

[0113] Equation Z ni *b1+b2-Z ni *Z mi *b3=Z mi Written in matrix form as follows:

[0114]

[0115] Where i ≤ k, and i and k are both positive integers;

[0116] in,

[0117] According to the adaptive weighted least squares method, X, B, and Y can be written in the following form:

[0118]

[0119] S2007, take the derivative of B with respect to H(B). The error is minimized when the derivative is 0. The solution is obtained.

[0120] B = (X) T WX) -1 X T WY.

[0121] Substituting the first impedance value and the second impedance value into the formula B = (X T WX) -1 X T In WY, the complex coefficients b1, b2, and b3 are obtained.

[0122] Specifically, the weighting function W(R) i ′) is R i A decreasing function, where R i ′=R i / R max R max This represents the maximum distance between the first impedance value and the target impedance value. Let Z... ni Using the real and imaginary parts as the x and y coordinates respectively, calculate the distance R between it and 50 ohms (50+0j). i Define W(R) as the weight function. W(R) is a decreasing function of R. When R1 > R2, W(R1) < W(R2), and W(R) > 0. Define the normalized distance R. i '=R i / R max 0≤R i '≤1, i=1, 2,...,K.

[0123] The adaptive weight function W can be any decreasing function. For example, it can (but is not limited to) be:

[0124]

[0125] or

[0126]

[0127] Where g > 0; h > 0; 0 < R i ′<1.

[0128] In summary, this invention provides an online network impedance matching measurement device and method. The device includes: a current detection circuit with a current sampling terminal and a current output terminal, wherein the current sampling terminal is mutually inducted with the transmitter transmission line, and the current output terminal outputs a current value; a voltage detection circuit with a voltage sampling terminal and a voltage output terminal, wherein the voltage sampling terminal is connected to any point on the transmitter transmission line, and the voltage output terminal outputs a voltage value; and a controller with a current input terminal, a voltage input terminal, and an impedance output terminal, wherein the current input terminal is connected to the current output terminal, and the voltage output terminal is connected to the voltage input terminal. The controller is used to obtain the impedance value Z based on the current and voltage values. mi And based on the pre-stored conversion function F(Z) mi b) Output the network impedance value, thereby realizing online measurement of network impedance. Online measurement of network impedance avoids transmitter shutdown and is highly practical.

[0129] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An online network impedance matching measurement device, characterized in that, include: A current detection circuit includes a current sampling terminal and a current output terminal. The current sampling terminal is mutually inducted with the inductance of the transmitter transmission line, and the current output terminal is used to output the current value. A voltage detection circuit includes a voltage sampling terminal and a voltage output terminal. The voltage sampling terminal is connected to any point on the transmitter transmission line, and the voltage output terminal is used to output a voltage value. The controller includes a current input terminal, a voltage input terminal, and an impedance output terminal. The current input terminal is connected to the current output terminal, and the voltage output terminal is connected to the voltage input terminal. The controller is used to obtain the impedance value Z based on the current value and the voltage value. mi And based on the pre-stored conversion function F(Z) mi b) Output the network impedance value; The transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) are, where, F(Z mi ,b)=(Z mi -b2) / (b1-Z mi *b3)。 2. The online network impedance matching measurement device according to claim 1, characterized in that, The current detection circuit includes: a first inductor, a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a first diode, a second diode, a third capacitor, and a fourth capacitor; The first inductor, the first capacitor, the second capacitor, the first resistor, and the second resistor are connected in parallel to form a first parallel circuit, and the first inductor is mutually inducted with the inductance of the transmitter transmission line; the third resistor and the fourth resistor are connected in series and then in parallel with the first parallel circuit to form a second parallel circuit; one end of the fifth resistor is connected to one end of the second parallel circuit, and the other end of the fifth resistor is connected to the anode of the first diode; one end of the sixth resistor is connected to the other end of the second parallel circuit, and the other end of the sixth resistor is connected to the anode of the second diode; the seventh resistor and the third capacitor are connected in parallel to form a third parallel circuit, and the eighth resistor and the fourth capacitor are connected in parallel to form a fourth parallel circuit; one end of the third parallel circuit is connected to the cathode of the first diode, one end of the fourth parallel circuit is connected to the cathode of the second diode, and the other end of the third parallel circuit is connected to the other end of the fourth parallel circuit.

3. The online network impedance matching measurement device according to claim 2, characterized in that, The voltage detection circuit includes: a second inductor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, and an eleventh capacitor; the sixth and seventh capacitors are connected in parallel to form a fifth parallel circuit; one end of the fifth capacitor is connected to the transmitter transmission line, and the other end of the fifth capacitor is connected to one end of the fifth parallel circuit, the other end of the fifth parallel circuit is grounded; one end of the eighth capacitor is connected to one end of the fifth parallel circuit, and the other end of the eighth capacitor is grounded; one end of the ninth capacitor is connected to one end of the fifth parallel circuit, and the other end of the ninth capacitor is grounded; one end of the tenth capacitor is connected to one end of the fifth parallel circuit, and the other end of the tenth capacitor is grounded; one end of the eleventh capacitor is connected to one end of the fifth parallel circuit, and the other end of the eleventh capacitor is grounded; one end of the second inductor is connected to one end of the fifth parallel circuit, and the other end of the second inductor is grounded; one end of the second inductor is also connected between the third and fourth resistors.

4. The online network impedance matching measurement device according to claim 3, characterized in that, Also includes: An analog-to-digital converter, wherein the current input terminal of the analog-to-digital converter is connected to the negative terminal of the first diode, and the voltage input terminal of the analog-to-digital converter is connected to the other end of the fifth capacitor; The current output terminal of the analog-to-digital converter is connected to the current input terminal of the controller, and the voltage output terminal of the analog-to-digital converter is connected to the voltage input terminal of the controller.

5. A method for online measurement of network impedance matching, characterized in that, Includes the following steps: Obtain the current and voltage of the transmitter transmission line; The impedance value Z is obtained based on the current and voltage of the transmitter transmission line. mi And according to the transformation function F(Z) mi b) Obtain the impedance value of the transmitter antenna; It also includes the following steps: The transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) are, where, F(Z mi ,b)=(Z mi -b2) / (b1-Z mi *b3)。 6. The online measurement method for network impedance matching according to claim 5, characterized in that, The transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) include the following steps: Obtain the i sets of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value; Obtain the impedance value Z of the i-th set of online measurement terminals of the network. mi This is denoted as the second impedance value, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i sets of online measured impedance values ​​Z of the network. i This is denoted as the third impedance value; Obtain the coordinate distance between the first impedance value and the target impedance value in each group, and denote it as the first distance R. i ; According to the first distance R i Construct the weight function W(R) i ′); Obtain the coordinate distance between the first impedance value and the third impedance value in each group, and denote it as the second distance; Based on the adaptive weighted least squares method, the weight function W(R) i ′) and the second distance constructs the error function E(b); where, Based on numerical calculations and nonlinear regression methods, the equation E(b)=∑ i W(R ′ i )|Z ni -F(Z mi b)| 2 Estimate the value of parameter b and solve for it. The weighting function W(R) i ′) is R i A decreasing function, where R i ′=R i / R max R max This is the maximum distance between the first impedance value and the target impedance value.

7. The online measurement method for network impedance matching according to claim 5, characterized in that, The transformation function F(Z) is estimated using the adaptive weighted least squares method. mi The complex coefficients b1, b2, and b3 in b) include the following steps: Obtain the i sets of offline measured impedance values ​​Z of the network. ni , denoted as the first impedance value; Obtain the impedance value Z of group i online measurement terminals. mi This is denoted as the second impedance value, based on the impedance value Z of the i-th group of online measurement terminals. mi and the transformation function F(Z) mi (b) Obtain the i sets of online measured impedance values ​​Z of the network. i This is denoted as the third impedance value; Obtain the coordinate distance between the first impedance value and the target impedance value in each group, and denote it as the first distance R. i ; According to the first distance R i Construct the weight function W(R) i ′); F(Z) will be obtained using the adaptive weighted least squares method. mi The matrix form of b): Let F(Z mi , b) = Z ni ; Obtain the relation Z ni *b1+b2-Z ni *Z mi *b3=Z mi ; Equation Z ni *b1+b2-Z ni *Z mi *b3=Z mi Written in matrix form as follows: Where i ≤ k, and i and k are both positive integers; in, According to the adaptive weighted least squares method, X, B, and Y can be written in the following form: Taking the derivative of B with respect to H(B), the solution is found when the derivative is 0. B=(X T WX) -1 X T WY; The weighting function W(R) i ′) is R i A decreasing function, where R i ′=R i / R max R max This is the maximum distance between the first impedance value and the target impedance value.

8. The online measurement method for network impedance matching according to claim 6 or 7, characterized in that, The decreasing function is: or Where g>0; h>0; 0 <R i ′<1.

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