Reflection gain evaluation and diagnosis method and device and electronic equipment

Abstract

The invention provides a reflection gain evaluation and diagnosis method and device and electronic equipment, and the method comprises the steps: obtaining a first reflection coefficient of a reflection amplification circuit when a network analyzer measures that system impedance is system characteristic impedance; compensating the first reflection coefficient to a radio frequency port plane when the tag is formed to obtain a first compensation reflection coefficient of the reflection amplification circuit; detecting a second reflection coefficient of the tag antenna placed in the housing; compensating the second reflection coefficient to an antenna port plane when the tag is formed to obtain a second compensation reflection coefficient of the tag antenna; and according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna, a reflection gain and a decibel value of the reflection gain are calculated. The method can truly and effectively evaluate the reflection gain when the reflection amplification circuit forms the tag, and is of great significance to link planning and steady work of a communication system formed by the reader and the distance enhanced tag.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a reflection gain evaluation and diagnosis method, device and electronic equipment. Background Art

[0002] Backscatter communication simplifies the transmission circuit by switching the load at the antenna port. It has the characteristics of low power consumption and low cost, and is attracting widespread attention from industry and academia. In the uplink communication from the tag to the reader, the reader transmits a single tone signal and transmits it to the tag. In the process of the tag modulating and reflecting it back to the reader, the signal experiences a two-way path loss, making the uplink communication signal weaker and limiting the communication distance. As a result, traditional backscatter communication cannot be used in more application scenarios.

[0003] Backscatter enhancement technology integrates the reflection amplifier circuit into the tag based on backscatter communication, amplifies and modulates the single-tone signal received by the tag and then transmits it. At the same distance, the signal power received by the reader is increased. When the reader sensitivity is constant, the tag can be farther away from the reader. Backscatter enhancement technology greatly increases the communication distance and expands the application scenarios of backscatter communication.

[0004] At present, there are many circuit design methods for achieving backscattering enhancement, such as using the negative resistance characteristics of tunnel diodes to build low-power high-gain reflection amplifier circuits, using transistor cross-coupling to form a single-ended input reflection amplifier circuit with negative resistance, or using positive feedback from the collector to the base of a single transistor to form a reflection amplifier circuit with negative resistance.

[0005] When evaluating the reflection gain, most literature uses a network analyzer to measure S11 (S parameter of port 1, i.e., reflection coefficient when the load is 50 Ohm) or uses a circulator, spectrum analyzer, or excitation source to measure the return gain, such as Figure 1 As shown in the figure, these measurement methods are all offline measurements and cannot evaluate the true reflection gain when the tag antenna is connected to the reflection discharge circuit. In addition, since the port impedance of the reflection amplifier circuit is negative resistance, when the tag antenna impedance does not match it, it is easy to oscillate. At this time, the signal returned by the tag to the reader includes both the self-excited oscillation signal of the reflection amplifier circuit and the signal transmitted from the reader to the tag and amplified by the tag through the reverse amplifier circuit. The reverse gain at this time is very different from that when the reverse amplification is measured alone. Summary of the invention

[0006] The purpose of the present application is to provide a reflection gain evaluation and diagnosis method, device and electronic equipment, which can truly and effectively evaluate the reflection gain of a reflection amplifier circuit when forming a tag, and is of great significance to the link planning and robust operation of a communication system composed of a reader and a distance-enhanced tag.

[0007] In a first aspect, the present application provides a method for evaluating and diagnosing a reflection gain, the method comprising: obtaining a first reflection coefficient of a reflection amplification circuit when the system impedance is measured as the system characteristic impedance by a network analyzer; compensating the first reflection coefficient to the RF port plane when forming a tag, to obtain a first compensated reflection coefficient of the reflection amplification circuit; detecting a second reflection coefficient when the tag antenna is placed in a housing; compensating the second reflection coefficient to the antenna port plane when forming the tag, to obtain a second compensated reflection coefficient of the tag antenna; and calculating the reflection gain and the decibel value of the reflection gain based on the first compensated reflection coefficient of the reflection amplification circuit and the second compensated reflection coefficient of the tag antenna.

[0008] Furthermore, the step of compensating the first reflection coefficient to the RF port plane when the tag is formed to obtain the first compensation reflection coefficient of the reflection amplifier circuit includes: compensating the first reflection coefficient to the RF port plane when the tag is formed according to the following first specified formula to obtain the first compensation reflection coefficient of the reflection amplifier circuit:

[0009]

[0010] Among them, Γ ra represents a first compensation reflection coefficient of the reflection amplifier circuit; represents the first reflection coefficient of the reflection amplifier circuit; θ1 is the first delay phase, β is the phase shift constant, L1 is the relative length from the calibration surface to the radio frequency port of the reverse amplifier circuit when forming the tag; θ1 is obtained by directly measuring the transmission phase shift of the printed conductor with the same length L1 on the circuit board with a network analyzer.

[0011] Furthermore, the step of compensating the second reflection coefficient to the antenna port plane when the tag is formed to obtain the second compensated reflection coefficient of the tag antenna includes: compensating the second reflection coefficient to the antenna port plane when the tag is formed according to the following second specified formula to obtain the second compensated reflection coefficient of the tag antenna:

[0012] θ2=β*L2;

[0013] Among them, Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the second reflection coefficient of the tag antenna; θ2 is the second delay phase, β is the phase shift constant, L2 is the relative length from the calibration surface to the antenna port when the tag is formed; θ2 can also be directly measured by a network analyzer.

[0014] Furthermore, the step of calculating the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna includes: calculating the reflection gain according to the following third specified formula:

[0015]

[0016] Where, Gain represents the reflection gain; Γ ra represents the first compensation reflection coefficient of the reflection amplifier circuit; Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the conjugate of the second compensation reflection coefficient.

[0017] Furthermore, the step of calculating the decibel value of the reflection gain according to the first compensation reflection coefficient of the reflection amplifier circuit and the second compensation reflection coefficient of the tag antenna includes: calculating the decibel value of the reflection gain according to the following fourth specified formula:

[0018]

[0019]

[0020] Among them, Gain dB Indicates the decibel value of the reflection gain.

[0021] Furthermore, the method further includes: improving the stability of the reflection gain by at least one of the following methods: connecting a reactance element in series or in parallel to the tag antenna so that the impedance of the tag antenna has the same sign as the imaginary part of the impedance of the reflection amplifier circuit; loop gain LoopGain = Γ ra Γ ant Reach the specified value -3dB; select a tag antenna with good impedance matching in a wide bandwidth and a small reflection coefficient amplitude, satisfying the following relationship: |Γ ant | max <1 / |Γ ra | max , the frequency range is within the operating frequency range of the reflection amplifier circuit.

[0022] Furthermore, the above-mentioned reactance element includes: an inductor or a capacitor; the tag antenna is a circularly polarized antenna with dual feed points.

[0023] In the second aspect, the present application also provides a reflection gain evaluation and diagnosis device, the device comprising: a coefficient determination module, used to obtain a first reflection coefficient of the reflection amplification circuit when the system impedance measured by a network analyzer is the system characteristic impedance; a first compensation module, used to compensate the first reflection coefficient to the RF port plane when the tag is composed, to obtain the first compensated reflection coefficient of the reflection amplification circuit; a coefficient detection module, used to detect the second reflection coefficient of the tag antenna placed in the housing; a second compensation module, used to compensate the second reflection coefficient to the antenna port plane when the tag is composed, to obtain the second compensated reflection coefficient of the tag antenna; a calculation module, used to calculate the reflection gain and the decibel value of the reflection gain based on the first compensated reflection coefficient of the reflection amplification circuit and the second compensated reflection coefficient of the tag antenna.

[0024] In a third aspect, the present application further provides an electronic device, comprising a processor and a memory, wherein the memory stores computer executable instructions that can be executed by the processor, and the processor executes the computer executable instructions to implement the method described in the first aspect above.

[0025] In a fourth aspect, the present application further provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions prompt the processor to implement the method described in the first aspect above.

[0026] In the reflection gain evaluation and diagnosis method, device and electronic device provided by the present application, firstly, when the system impedance is measured by a network analyzer as the system characteristic impedance, the first reflection coefficient of the reflection amplifier circuit is obtained; then the first reflection coefficient is compensated to the RF port plane when the tag is composed, and the first compensation reflection coefficient of the reflection amplifier circuit is obtained; the second reflection coefficient of the tag antenna placed in the housing is detected; the second reflection coefficient is compensated to the antenna port plane when the tag is composed, and the second compensation reflection coefficient of the tag antenna is obtained; finally, the reflection gain and the decibel value of the reflection gain are calculated based on the first compensation reflection coefficient of the reflection amplifier circuit and the second compensation reflection coefficient of the tag antenna. The present application can truly and effectively evaluate the reflection gain of the reflection amplifier circuit when the tag is composed, which is of great significance to the link planning and robustness of the communication system composed of the reader and the distance enhanced tag. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 A schematic diagram of a return gain measurement in the prior art;

[0029] Figure 2 A flow chart of a reflection gain evaluation and diagnosis method provided in an embodiment of the present application;

[0030] Figure 3 A schematic diagram of an antenna and a reflection amplifier circuit impedance provided in an embodiment of the present application;

[0031] Figure 4 A schematic diagram of measuring the reflection coefficient of a reflection amplifier circuit provided in an embodiment of the present application;

[0032] Figure 5 A schematic diagram of an antenna with a stable reflection amplifier circuit gain provided in an embodiment of the present application;

[0033] Figure 6 A schematic diagram of a dual-feed circularly polarized antenna connected to a reflection amplification circuit to avoid oscillation provided in an embodiment of the present application;

[0034] Figure 7 A structural block diagram of a reflection gain evaluation and diagnosis device provided in an embodiment of the present application;

[0035] Figure 8 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0036] The technical solution of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0037] In view of the problem that most of the evaluations of reflection gain in the prior art are offline measurements, it is impossible to evaluate the real reflection gain when the tag antenna is connected to the reflection amplifier circuit. Also, since the port impedance of the reflection amplifier circuit is negative resistance, when the tag antenna impedance does not match it, it is easy to produce oscillations, resulting in a huge difference between the reverse gain at this time and the reverse gain measured alone. The embodiment of the present application provides a reflection gain evaluation and diagnosis method, device and electronic device, which can truly and effectively evaluate the reflection gain when the reflection amplifier circuit constitutes a tag, and is of great significance to the link planning and robust operation of the communication system composed of a reader and a distance-enhanced tag.

[0038] To facilitate understanding of this embodiment, a reflection gain evaluation and diagnosis method disclosed in an embodiment of the present application is first introduced in detail.

[0039] Figure 2 A flow chart of a reflection gain evaluation and diagnosis method provided in an embodiment of the present application, the method comprising the following steps:

[0040] Step S202, when the system impedance is measured by a network analyzer as the system characteristic impedance, a first reflection coefficient of the reflection amplifier circuit is obtained;

[0041] When the system impedance is measured as Z0 using a network analyzer, the reflection coefficient of the reflection amplifier circuit is

[0042] Step S204, compensating the first reflection coefficient to the RF port plane when the tag is formed, to obtain a first compensation reflection coefficient of the reflection amplifier circuit;

[0043] Since the reflection amplifier circuit port needs to be made into a separate board and connected to an external RF connector when measuring separately, this measurement value needs to be compensated to the RF port plane when forming the tag, and Γ is obtained. ra The specific compensation process will be described in detail later.

[0044] Step S206, detecting a second reflection coefficient of the tag antenna placed in the housing;

[0045] Since the reflection coefficient of the tag antenna is ant Affected by the measurement environment, such as when the tag antenna is close to metal, installed in a housing, or in free space, the reflection coefficient Γ ant There will be a big difference, and even the resonant frequency of the tag antenna will seriously deviate from the center frequency. The tag antenna needs to be placed in the housing and installed in a real environment to measure the second reflection coefficient of the tag antenna.

[0046] Step S208, compensating the second reflection coefficient to the antenna port plane when the tag is formed, to obtain a second compensated reflection coefficient of the tag antenna;

[0047] Likewise, the second reflection coefficient It is also necessary to compensate to the antenna port plane when forming the tag, and obtain Γ ant .

[0048] Step S210: Calculate the reflection gain and the decibel value of the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna.

[0049] Finally, according to the first compensation reflection coefficient Γ of the reflection amplifier circuit after compensation above ra , and the second compensation reflection coefficient Γ of the tag antenna ant , calculate the reflection gain and the decibel value of the reflection gain.

[0050] In the reflection gain evaluation and diagnosis method provided in the embodiment of the present application, by respectively compensating the first reflection coefficient of the reflection amplifier circuit and the second reflection coefficient of the tag antenna, the reflection gain and the decibel value of the reflection gain are calculated using the compensated coefficients. This can truly and effectively evaluate the reflection gain of the reflection amplifier circuit when forming a tag, which is of great significance to the link planning and robust operation of the communication system composed of the reader and the distance enhanced tag.

[0051] The embodiment of the present application also provides another method for evaluating and diagnosing the reflected gain, which is implemented on the basis of the above embodiment; this embodiment focuses on describing the derivation process of the gain calculation formula, the specific compensation process and the reverse gain stabilization method.

[0052] See also Figure 3 The connection block diagram of the reflection amplifier circuit and the tag antenna is shown in FIG. 1 . The reflection coefficient of the antenna is Γ ant , the impedance is Z ant The reflection coefficient of the reflection amplifier circuit is Γ ra , the impedance is Z ra , Z0 is the system characteristic impedance.

[0053] The relationship between antenna reflection coefficient and impedance is:

[0054] The relationship between the reflection coefficient and impedance of the reflection amplifier circuit is:

[0055] The direct expression of reflection gain is:

[0056] After derivation, the reflection gain of the tag is expressed by the reflection coefficient of the antenna and the reflection coefficient of the reflection amplifier circuit:

[0057]

[0058] Expressed in dB:

[0059]

[0060] Therefore, a measurement method to truly evaluate the reflection gain when forming a tag is as follows:

[0061] The reflection coefficient of the reflection amplifier circuit is measured by a network analyzer when the system impedance is Z0. Since the reflection amplifier circuit port needs to be made into a separate board and connected to an external RF connector when measuring separately, this measurement value needs to be compensated to the RF port plane when forming the tag, such as Figure 4 As shown in (a),

[0062] θ1=β*L1,

[0063] Among them, Γ ra represents a first compensation reflection coefficient of the reflection amplifier circuit; represents the first reflection coefficient of the reflection amplifier circuit; θ1 is the first delay phase, β is the phase shift constant, L1 is the relative length from the calibration surface to the RF port of the reverse amplifier circuit when forming the tag; it can be positive or negative, positive from the calibration surface (circuit board port) to the network analyzer, and negative from the calibration surface (circuit board port) to the network analyzer; θ1 is obtained by directly measuring the transmission phase shift (ph(S21)) of the printed conductor with the same length L1 on the circuit board by the network analyzer, as shown in Figure 4 (b) as shown.

[0064] Since the reflection coefficient of the tag antenna is ant Affected by the measurement environment, such as when the tag antenna is close to metal, installed in a housing, or in free space, the reflection coefficient Γ ant There will be a big difference, and even the resonant frequency of the tag antenna will seriously deviate from the center frequency. The tag antenna needs to be placed in the housing and installed in the real environment to measure the reflection coefficient. Likewise, this measurement It is also necessary to compensate for the antenna port plane when forming the tag, as shown in the following formula:

[0065] θ2=β*L2;

[0066] Among them, Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the second reflection coefficient of the tag antenna; θ2 is the second delay phase, β is the phase shift constant, L2 is the relative length from the calibration surface to the antenna port when the tag is formed; it can be positive or negative. θ2 is directly measured by a network analyzer using the same method. Figure 4 (a).

[0067] Further, the step of calculating the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna includes:

[0068] Calculate the reflection gain according to the following first specified formula:

[0069]

[0070] Where, Gain represents the reflection gain; Γ ra represents the first compensation reflection coefficient of the reflection amplifier circuit; Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the conjugate of the second compensation reflection coefficient.

[0071] The step of calculating the decibel value of the reflection gain according to the first compensation reflection coefficient of the reflection amplifier circuit and the second compensation reflection coefficient of the tag antenna includes: calculating the decibel value of the reflection gain according to the following second specified formula:

[0072]

[0073] Among them, Gain dB Indicates the decibel value of the reflection gain.

[0074] In addition, the embodiment of the present application avoids self-oscillation of the tag in the initial design stage. That is, when designing the tag, the relevant indicators are consciously simulated and calculated according to this method, and pre-adjusted, so as to construct the reflection gain evaluation and diagnosis method as described above, which can effectively evaluate the real reflection gain of the tag and the potential oscillation risk, and avoid the gain deviation caused by only measuring the reflection amplifier circuit.

[0075] When the reflection amplifier circuit is connected to the tag antenna, the tag will tend to oscillate because the impedance of the tag antenna is far from the center of the circle on the SMITH circle. If this phenomenon is noticed during the design and debugging of the reflection amplifier circuit and tag antenna, and the parameters are properly debugged, oscillation and gain changes can be avoided, making the reflection gain more stable.

[0076] According to formula (1), when Zant = Z0, Γ ant =0, at this time the reflection gain of the reflection amplifier circuit is Gain dB =20*log|Γ ra |, which corresponds to the gain when the reflection amplifier circuit is tested alone using a network analyzer or reflectometer.

[0077] Γ ra Γ ant When =1, the reflection gain is infinite and the system oscillates.

[0078] Calculation example:

[0079] Γ ra =3.16 (expected reflection gain = 20*log(3.16) = 10 dB), Γ ant =0.316; the reflection gain is: Gain dB =20*log(3.16-0.316)-20log(1-0.9985)=65.47dB, the reflection gain is as high as over 60dB, so the probability of oscillation after forming the tag will be extremely high.

[0080] Γ ra=3.16 (expected reflection gain = 20*log(3.16) = 10 dB), Γ ant =-0.316; the reflection gain is: GaindB = 20*log(3.16+0.316)-20log(1+0.9985) = 4.8dB. The reflection gain will be more than 5dB smaller than the expected gain.

[0081] It can be seen from the above example that if the gain of the reflection amplifier circuit is required to reach the expected gain, the amplitude of the antenna reflection coefficient needs to be reduced as much as possible.

[0082] From the gain expressions (3) and (4), it can be seen that to avoid oscillation, the denominator must not be zero.

[0083] That is: Z ra +Z ant ≠0 or 1-Γ ra Γ ant ≠0. These two conditions are equivalent. Define loop gain LoopGain = Γ ra Γ ant .

[0084] The methods to avoid oscillation and increase the stability of the reflection amplifier circuit are as follows:

[0085] (a) Connect a reactive element (such as an inductor or capacitor) in series or in parallel with the tag antenna to make the tag antenna impedance Z ant The impedance Z of the reflection amplifier circuit ra The imaginary part has the same sign; in |Γ ra Γ ant All frequency points of |≥1 should meet the requirement.

[0086] (b) Design stability margin: Loop gain LoopGain = Γ ra Γ ant Reach the specified value -3dB;

[0087] Considering the accuracy of measuring the reflection coefficient, the design index meets the loop gain LoopGain of -3dB, so there is a stability margin of about 3dB to ensure 1-Γ ra Γ ant ≠0, and |Γ ra Γ ant |<1. When the antenna is selected, adjust the reflection coefficient Γ of the reflection amplifier circuit ra , making LoopGain <= -3dB.

[0088] (c) Select a tag antenna with good impedance matching in a wide bandwidth and a small reflection coefficient amplitude, satisfying the following relationship: |Γ ant | max <1 / |Γ ra| max , the frequency range is within the operating frequency range of the reflection amplifier circuit.

[0089] Since Γ ant = 0, the physical meaning is that the antenna has no reflection, and no oscillation will occur at this time. This only corresponds to the ideal situation and is not actually possible. However, an antenna with a very small reflection coefficient in the broadband can be selected. Under the condition of satisfying the above relationship, the tag can be guaranteed to be stable and will not oscillate. Here is a typical applicable example, that is, a circularly polarized antenna with dual feed points.

[0090] The theoretical analysis is as follows:

[0091] like Figure 5 As shown, ANT1 and ANT2 are two feeding ports of the antenna, which are two polarization modes: vertical and horizontal, and the two ports have the same reflection coefficient. ANT1 and ANT2 are connected to the 0° and 90° ports of the orthogonal coupler. The ISO port is connected to a 50 ohm load. The RF port is connected to the RF port of the RF reflection amplifier circuit.

[0092] ANT1, ANT2 and the orthogonal coupler constitute a dual-feed circularly polarized antenna.

[0093] like Figure 6 As shown in the figure, when receiving linear polarization waves, for example, ANT1 receives vertical linear polarization waves, and ANT2 has the opposite polarization direction and does not receive. The 0° port is isolated from the 90° port, and the linear polarization wave received by ANT1 passes through the orthogonal coupler, and the signal is evenly distributed to the IN port and ISO port. The signal transmitted to the ISO port is absorbed by the matching load.

[0094] Since the IN port is connected to the reflection amplifier circuit, the signal after reflection amplification is input into the orthogonal coupler from the IN port. Then the power is evenly divided from the 0° and 90° ports, and the phase difference is 90°. Since the ANT1 and ANT2 ports have the same reflection coefficient, the signals reflected from ANT1 and ANT2 return to the coupler along the original path. At the IN port, the signal reflected from ANT2 undergoes two 90° phase shifts, and is inversely phased and equal in amplitude to the signal reflected from ANT1, and the superposition is zero. At the ISO port, the two are in the same direction, and the power is consumed in the matching resistor. ANT2 receives linearly polarized waves in the same way as above.

[0095] When receiving circular polarized waves, the signal received by ANT1 has a 90° phase shift compared to that of ANT2. After passing through the orthogonal directional coupler, the signal input by ANT2 is shifted by 90° to the IN port, and the signal input by ANT1 is shifted by 0° to the IN port, plus the original 90° phase shift. The two are superimposed in phase. At the ISO port, they are reversely subtracted. Just like the analysis when receiving linear polarized waves, the received signal is output after reflection amplification and will not be reflected to the reflection amplifier circuit again.

[0096] Therefore, this antenna can theoretically achieve zero reflection, but due to the manufacturing process and insufficient electrical performance of the coupler, there is still a very small reflection. However, this antenna can still provide a good broadband impedance matching characteristic for the reflection amplifier circuit, thereby ensuring the gain stability of the reverse amplification when forming the tag and avoiding the generation of oscillation.

[0097] Based on the above method embodiment, the present application embodiment also provides a reflection gain evaluation and diagnosis device, see Figure 7 As shown, the device includes: a coefficient determination module 702, which is used to obtain a first reflection coefficient of the reflection amplification circuit when the system impedance is measured by a network analyzer as the system characteristic impedance; a first compensation module 704, which is used to compensate the first reflection coefficient to the RF port plane when the tag is composed, and obtain the first compensated reflection coefficient of the reflection amplification circuit; a coefficient detection module 706, which is used to detect the second reflection coefficient of the tag antenna placed in the shell; a second compensation module 708, which is used to compensate the second reflection coefficient to the antenna port plane when the tag is composed, and obtain the second compensated reflection coefficient of the tag antenna; a calculation module 710, which is used to calculate the reflection gain and the decibel value of the reflection gain according to the first compensated reflection coefficient of the reflection amplification circuit and the second compensated reflection coefficient of the tag antenna.

[0098] Furthermore, the first compensation module 704 is used to compensate the first reflection coefficient to the RF port plane when the tag is formed according to the first specified formula to obtain a first compensation reflection coefficient of the reflection amplifier circuit:

[0099] θ1=β*L1;

[0100] Among them, Γ ra represents a first compensation reflection coefficient of the reflection amplifier circuit; represents the first reflection coefficient of the reflection amplifier circuit; θ1 is the first delay phase, β is the phase shift constant, L1 is the relative length from the calibration surface to the radio frequency port of the reverse amplifier circuit when forming the tag; θ1 is obtained by directly measuring the transmission phase shift of the printed conductor with the same length L1 on the circuit board with a network analyzer.

[0101] Furthermore, the second compensation module 708 is used to compensate the second reflection coefficient to the antenna port plane when the tag is formed according to the second specified formula to obtain the second compensation reflection coefficient of the tag antenna:

[0102] θ2=β*L2;

[0103] Among them, Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the second reflection coefficient of the tag antenna; θ2 is the second delay phase, β is the phase shift constant, L2 is the relative length from the calibration surface to the antenna port when the tag is formed; θ2 is directly measured by a network analyzer.

[0104] Furthermore, the calculation module 710 is used to calculate the reflection gain according to the following third specified formula:

[0105]

[0106] Where, Gain represents the reflection gain; Γ ra represents the first compensation reflection coefficient of the reflection amplifier circuit; Γ ant represents the second compensation reflection coefficient of the tag antenna; represents the conjugate of the second compensation reflection coefficient.

[0107] Furthermore, the calculation module 710 is used to calculate the decibel value of the reflection gain according to the following fourth specified formula:

[0108]

[0109] Among them, Gain dB Indicates the decibel value of the reflection gain.

[0110] Furthermore, the above device also includes: a stabilization module, which is used to improve the stability of the reflection gain by at least one of the following methods: connecting a reactance element in series or in parallel to the tag antenna so that the impedance of the tag antenna has the same sign as the imaginary part of the impedance of the reflection amplifier circuit; loop gain LoopGain = Γ ra Γ ant Reach the specified value -3dB; select an antenna with good impedance matching in a wide bandwidth and a small reflection coefficient amplitude, satisfying the following relationship: |Γ ant | max <1 / |Γ ra | max , the frequency range is within the operating frequency range of the reflection amplifier circuit.

[0111] Furthermore, the above-mentioned reactance element includes: an inductor or a capacitor; the tag antenna is a circularly polarized antenna with dual feed points.

[0112] The device provided in the embodiment of the present application has the same implementation principle and technical effects as those of the aforementioned method embodiment. For the sake of brief description, for matters not mentioned in the embodiment of the device, reference may be made to the corresponding contents in the aforementioned method embodiment.

[0113] The present application also provides an electronic device, such as Figure 8As shown, it is a schematic diagram of the structure of the electronic device, wherein the electronic device includes a processor 81 and a memory 80, the memory 80 stores computer executable instructions that can be executed by the processor 81, and the processor 81 executes the computer executable instructions to implement the above method.

[0114] exist Figure 8 In the illustrated embodiment, the electronic device further includes a bus 82 and a communication interface 83 , wherein the processor 81 , the communication interface 83 and the memory 80 are connected via the bus 82 .

[0115] Among them, the memory 80 may include a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 83 (which can be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The bus 82 can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus 82 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 8 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0116] The processor 81 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit or software instructions in the processor 81. The above processor 81 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to be executed, or the hardware and software modules in the decoding processor can be executed. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor 81 reads the information in the memory and completes the steps of the method of the above embodiment in combination with its hardware.

[0117] An embodiment of the present application also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions prompt the processor to implement the above method. The specific implementation can be found in the aforementioned method embodiment, which will not be repeated here.

[0118] The computer program products of the methods, devices, and electronic devices provided in the embodiments of the present application include a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the previous method embodiments. The specific implementation can be found in the method embodiments, which will not be repeated here.

[0119] Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0120] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0121] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0122] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for evaluating and diagnosing reflection gain, characterized in that: The method comprises: When the system impedance is measured by the network analyzer as the system characteristic impedance, a first reflection coefficient of the reflection amplifier circuit is obtained; Compensating the first reflection coefficient to the RF port plane when forming the tag, to obtain a first compensated reflection coefficient of the reflection amplifier circuit; detecting a second reflection coefficient of the tag antenna placed in the housing; Compensating the second reflection coefficient to the antenna port plane when forming the tag, to obtain a second compensated reflection coefficient of the tag antenna; According to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna, the reflection gain and the decibel value of the reflection gain are calculated.

2. The method according to claim 1, characterized in that The step of compensating the first reflection coefficient to the RF port plane when forming the tag to obtain the first compensated reflection coefficient of the reflection amplifier circuit includes: The first reflection coefficient is compensated to the RF port plane when the tag is formed according to the following first specified formula to obtain the first compensation reflection coefficient of the reflection amplifier circuit: Among them, Γ ra represents a first compensation reflection coefficient of the reflection amplification circuit; represents the first reflection coefficient of the reflection amplifier circuit; θ1 is the first delay phase, β is the phase shift constant, L1 is the relative length from the calibration surface to the radio frequency port of the reverse amplifier circuit when forming the tag; θ1 is obtained by directly measuring the transmission phase shift of the printed conductor with the same length L1 on the circuit board with a network analyzer.

3. The method according to claim 1, characterized in that The step of compensating the second reflection coefficient to the antenna port plane when forming the tag to obtain the second compensated reflection coefficient of the tag antenna includes: The second reflection coefficient is compensated to the antenna port plane when the tag is formed according to the following second specified formula to obtain the second compensated reflection coefficient of the tag antenna: Among them, Γ ant represents a second compensation reflection coefficient of the tag antenna; represents the second reflection coefficient of the tag antenna; θ2 is the second delay phase, β is the phase shift constant, L2 is the relative length from the calibration surface to the antenna port when the tag is formed; θ2 is directly measured by a network analyzer.

4. The method according to claim 1, characterized in that: The step of calculating the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna comprises: The reflection gain is calculated according to the third specified formula as follows: Where, Gain represents the reflection gain; Γ ra represents the first compensation reflection coefficient of the reflection amplifier circuit; Γ ant represents a second compensation reflection coefficient of the tag antenna; represents the conjugate of the second compensating reflection coefficient.

5. The method according to claim 4, characterized in that The step of calculating the decibel value of the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna comprises: According to the fourth specified formula below, calculate the decibel value of the reflection gain: Among them, Gain dB Indicates the decibel value of the reflection gain.

6. The method according to claim 4, characterized in that The method further comprises: The stability of the reflection gain is improved by at least one of the following methods: Connecting a reactance element in series or in parallel to the tag antenna so that the impedance of the tag antenna has the same sign as the imaginary part of the impedance of the reflection amplifier circuit; Loop gain LoopGain = Γ ra Γ ant Reach the specified value -3dB; Select a tag antenna with good impedance matching in a wide bandwidth and a small reflection coefficient amplitude to satisfy the following relationship: |Γ ant | max <1 / |Γ ra | max , the frequency range is within the operating frequency range of the reflection amplifier circuit.

7. The method according to claim 6, characterized in that The reactive element includes: an inductor or a capacitor; the tag antenna is a circularly polarized antenna with dual feed points.

8. A reflection gain evaluation and diagnosis device, characterized in that: The device comprises: A coefficient determination module, used for obtaining a first reflection coefficient of the reflection amplifier circuit when the system impedance measured by a network analyzer is the system characteristic impedance; A first compensation module, used for compensating the first reflection coefficient to the RF port plane when forming the tag, to obtain a first compensation reflection coefficient of the reflection amplifier circuit; A coefficient detection module, used to detect a second reflection coefficient of the tag antenna when it is placed in the housing; A second compensation module is used to compensate the second reflection coefficient to the antenna port plane when the tag is formed, so as to obtain a second compensated reflection coefficient of the tag antenna; The calculation module is used to calculate the reflection gain and the decibel value of the reflection gain according to the first compensation reflection coefficient of the reflection amplification circuit and the second compensation reflection coefficient of the tag antenna.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer executable instructions that can be executed by the processor, and the processor executes the computer executable instructions to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are called and executed by a processor, the computer-executable instructions prompt the processor to implement the method according to any one of claims 1 to 7.

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