A filter power amplifier based on matched filter synthesis

Abstract

The invention discloses a filter power amplifier based on matched filtering synthesis, which belongs to the technical field of microwave power amplifiers and comprises: an input matching network, a gate bias circuit, a transistor and an output matching network; the input matching network matches a wave source impedance to a transistor input impedance; the gate bias circuit provides a stable DC path for the transistor; the transistor amplifies a wave source signal; the output matching network matches the transistor output impedance to a load impedance and simultaneously performs bandpass filtering, and a filter coupling matrix with an impedance conversion function can be directly synthesized by introducing a power wave scattering parameter, and a resonator with miniaturization and harmonic suppression functions can be quickly designed by introducing an anti-parallel coupling structure, and an output matching network with a filtering function can be designed in combination with the coupling matrix, so that bandwidth controllability, bandpass filtering and harmonic suppression can be achieved while ensuring the performance of the power amplifier, and the size of a radio frequency front end can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of microwave power amplifiers, and in particular to a filter power amplifier based on matched filter synthesis. Background Art

[0002] Wireless communication technology is gradually changing the fields of medicine, transportation, military, etc., and has an important impact on people's lives and even the development of the country. Wireless communication is developing towards high data rates and high user usage, and the power amplifier, as an important component of the transmitter, has an important impact on the performance of the transmitter. Therefore, high-performance power amplifiers have always received extensive attention from researchers.

[0003] In traditional transmitters, the power amplifier amplifies the input signal while suppressing out-of-band interference through the cascade filter. This discrete design will increase the layout area and is difficult to miniaturize. The insertion loss of the filter increases the signal attenuation, and the input and output impedances of the cascade ports are not 50 ohms, which will cause interconnection mismatch. The collaborative design of the filter as the output matching structure of the power amplifier can effectively solve the above problems. Summary of the invention

[0004] In order to solve the problem that the existing power amplifier needs to satisfy the functions of bandpass filtering and harmonic suppression at the same time, while taking into account the characteristics of miniaturization, the present invention provides a filter power amplifier based on matched filter synthesis, including: an input matching network, a gate bias circuit, a transistor and an output matching network;

[0005] The input matching network matches the wave source impedance to the transistor input impedance;

[0006] The gate bias circuit provides a stable DC path for the transistor;

[0007] The transistor amplifies the wave source signal;

[0008] The output matching network matches the transistor output impedance to the load impedance and performs bandpass filtering at the same time.

[0009] Further, the output matching network includes a tuning line and a bandpass filter for fundamental wave matching, bandpass filtering and harmonic suppression;

[0010] The tuning line is electrically connected to the bandpass filter.

[0011] Further: the bandpass filter includes a first resonator, a second resonator and a third resonator;

[0012] The first resonator and the second resonator are gap-coupled and connected;

[0013] The second resonator and the third resonator are slot-coupled.

[0014] Further: the first resonator includes a first microstrip line TL1, a second microstrip line TL2 and a third microstrip line TL3;

[0015] The first microstrip line TL1 is electrically connected to one end of the second microstrip line TL2, and the other end of the second microstrip line TL2 is electrically connected to the third microstrip line TL3;

[0016] The other end of the second microstrip line TL2 is arranged perpendicular to the third microstrip line TL3;

[0017] The second resonator includes a fourth microstrip line TL4, a fifth microstrip line TL5, a sixth microstrip line TL6, a seventh microstrip line TL7, an eighth microstrip line TL8, a ninth microstrip line TL9, a tenth microstrip line TL10 and an eleventh microstrip line TL11;

[0018] The fourth microstrip line TL4 is electrically connected to one end of the fifth microstrip line TL5 and one end of the seventh microstrip line TL7;

[0019] The fifth microstrip line TL5 and the seventh microstrip line TL7 are both arranged perpendicular to the fourth microstrip line TL4;

[0020] The other end of the fifth microstrip line TL5 is electrically connected to one end of the sixth microstrip line TL6;

[0021] The other end of the seventh microstrip line TL7 is electrically connected to the ninth microstrip line TL9 and is arranged vertically;

[0022] The other end of the fifth microstrip line TL5 and one end of the eighth microstrip line TL8 are electrically connected to the sixth microstrip line TL6;

[0023] The fifth microstrip line TL5 and the eighth microstrip line TL8 are both arranged perpendicular to the sixth microstrip line TL6;

[0024] The other end of the eighth microstrip line TL8 is electrically connected to one end of the tenth microstrip line TL10;

[0025] The eighth microstrip line TL8 is arranged perpendicular to the tenth microstrip line TL10;

[0026] The other end of the tenth microstrip line TL10 is electrically connected to the eleventh microstrip line TL11;

[0027] The ninth microstrip line TL9 is anti-parallel coupled to the tenth microstrip line TL10;

[0028] The third resonator includes a twelfth microstrip line TL12, a thirteenth strip line TL13 and a fourteenth strip line TL14;

[0029] The twelfth microstrip line TL12 is electrically connected to one end of the thirteenth strip line TL13, and the other end of the thirteenth strip line TL13 is electrically connected to the fourteenth strip line TL14;

[0030] The other end of the thirteenth strip line TL13 is arranged perpendicular to the fourteenth strip line TL14;

[0031] The third strip line TL3 and the fourteenth strip line TL14 are both coupled and connected in parallel with the fifth microstrip line TL5;

[0032] The seventh microstrip line TL7 and the eighth microstrip line TL8 are both parallel to the fifth microstrip line TL5;

[0033] The first microstrip line TL1 and the second microstrip line TL2 are both coupled and connected in parallel with the fourth microstrip line TL4;

[0034] The twelfth microstrip line TL12 and the thirteenth microstrip line TL13 are both coupled and connected in parallel with the sixth microstrip line TL6 .

[0035] Further: the ninth microstrip line TL9 and the tenth microstrip line TL10 are equal in length;

[0036] The fourth microstrip line TL4 and the sixth microstrip line TL6 are equal in length;

[0037] The fourth microstrip line TL4, the fifth microstrip line TL5 and the sixth microstrip line TL6 have the same width.

[0038] Furthermore, the characteristic impedance of the tuning line ranges from 30 to 50 ohms, and the electrical length ranges from 14° to 26°.

[0039] Furthermore, the lengths of the first resonator and the third resonator are both λ g / 4,λ g is the resonant frequency and waveguide wavelength.

[0040] Furthermore, the admittance matrix expression of the bandpass filter is as follows:

[0041]

[0042] Among them, E′(s) and F′(s) are N-order polynomials, N is the filter order, P′(s) is N-TZ-order polynomial, TZ is the number of finite transmission zeros, E′ * (s) and the roots of E′(s) are symmetric about the imaginary axis of the complex plane, y d is the element denominator of [y], y 12n ,y 21n and22n For element molecules.

[0043] The present invention provides a filter power amplifier based on matched filter synthesis. By introducing power wave scattering parameters, a filter coupling matrix with an impedance transformation function can be directly synthesized. By introducing an anti-parallel coupling structure, an improved open ring resonator with miniaturization and a parasitic resonance frequency greater than the third harmonic can be quickly designed. An output matching network with a filtering function is designed in combination with the coupling matrix. While ensuring the performance of the power amplifier, bandwidth control, bandpass filtering and harmonic suppression are achieved, and the size of the radio frequency front end is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 It is a principle block diagram of a filter power amplifier based on matched filter synthesis of the present invention;

[0046] Figure 2 It is an output matching structure diagram of a filter power amplifier based on matched filter synthesis of the present invention;

[0047] Figure 3 This is a graph showing the optimal load impedance value changing with frequency after the tuning line of the output matching circuit of the present invention is transformed;

[0048] Figure 4 is a result diagram of the resonance characteristics of the second resonator of the present invention;

[0049] Figure 5 It is a result diagram of S parameters of the filter power amplifier based on matched filter synthesis of the present invention;

[0050] Figure 6 This is a graph showing the output power and gain of the filter power amplifier based on matched filter synthesis according to the present invention changing with the input power.

[0051] In the figure: 1. input matching network, 2. gate bias circuit, 3. transistor and output matching network, 4. output matching network, 4-1. tuning line; 4-2. pass filter 4-2, 4-2-1. first resonator, 4-2-2. second resonator, 4-2-3. third resonator. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0054] Figure 1 The principle block diagram of the filter power amplifier based on matched filter synthesis of the present invention is as follows: A filter power amplifier based on matched filter synthesis includes an input matching network 1, a gate bias circuit 2, a transistor 3 and an output matching network 4;

[0055] The input matching network 1 matches the wave source impedance to the input impedance of the transistor 3;

[0056] The gate bias circuit 2 is composed of λ g / 4 microstrip line and multiple orders of magnitude capacitors, presenting high impedance to RF signals at the drain and gate of the transistor to suppress RF signals and filter out low-frequency noise, but allowing DC signals to pass smoothly, providing a stable DC path for the transistor 3;

[0057] The transistor 3 amplifies the wave source signal;

[0058] The output matching network 4 matches the output impedance of the transistor 3 to the load impedance and performs bandpass filtering at the same time.

[0059] The input matching network 1 and the output matching network 4 have an important influence on the performance indicators such as the gain and efficiency of the power amplifier, but the input matching network has a small influence on harmonic suppression, so the input matching network 1 only performs fundamental matching;

[0060] The specific connection process of the filter power amplifier based on matched filter synthesis of the present invention is as follows:

[0061] The input end of the input matching network 1 is connected to the wave source, and the output end of the input matching network 1 is connected to the gate bias circuit 2 and the input end of the transistor 3; it is mainly used to achieve optimal source impedance matching;

[0062] The gate bias circuit 2 is connected to the input end of the transistor 3, and the transistor 3 is connected to the output matching network 4;

[0063] The output matching network 4 includes a tuning line 4-1 and a bandpass filter 4-2 with fundamental wave matching, bandpass filtering and harmonic suppression functions; the tuning line 4-1 is connected between the transistor 3 and the bandpass filter 4-2;

[0064] The bandpass filter 4-2 includes a first resonator 4-2-1, a second resonator 4-2-2 and a third resonator 4-2-3;

[0065] The first resonator 4-2-1 and the second resonator 4-2-2 are connected by slot coupling;

[0066] The second resonator 4-2-2 and the third resonator 4-2-3 are connected via slot coupling;

[0067] Combination Figure 1 , the input matching circuit 1 is implemented by three cascaded microstrip lines and a parallel single branch line;

[0068] A tuning line 4-1 is connected between the output end of the transistor 3 and the bandpass filter 4-2; the lengths of the first resonator 4-2-1 and the third resonator 4-3-1 are λ g / 4,λ g The waveguide wavelength is the resonant frequency to achieve second harmonic suppression;

[0069] The transistor 3 is NPTB00004A, the working mode is class AB, and the drain DC voltage is 28V.

[0070] Figure 2 The output matching structure diagram of the filter power amplifier based on matched filter synthesis of the present invention is as follows: Figure 2 As shown, the first resonator 4-2-1 includes a first microstrip line TL1, a second microstrip line TL2 and a third microstrip line TL3;

[0071] The first microstrip line TL1 is electrically connected to one end of the second microstrip line TL2, and the other end of the second microstrip line TL2 is electrically connected to the third microstrip line TL3;

[0072] The other end of the second microstrip line TL2 is arranged perpendicular to the third microstrip line TL3;

[0073] The second resonator (4-2-2) includes a fourth microstrip line TL4, a fifth microstrip line TL5, a sixth microstrip line TL6, a seventh microstrip line TL7, an eighth microstrip line TL8, a ninth microstrip line TL9, a tenth microstrip line TL10 and an eleventh microstrip line TL11;

[0074] The fourth microstrip line TL4 is electrically connected to one end of the fifth microstrip line TL5 and one end of the seventh microstrip line TL7;

[0075] The fifth microstrip line TL5 and the seventh microstrip line TL7 are both arranged perpendicular to the fourth microstrip line TL4;

[0076] The other end of the fifth microstrip line TL5 is electrically connected to one end of the sixth microstrip line TL6;

[0077] The other end of the seventh microstrip line TL7 is electrically connected to the ninth microstrip line TL9 and is arranged vertically;

[0078] The other end of the fifth microstrip line TL5 and one end of the eighth microstrip line TL8 are electrically connected to the sixth microstrip line TL6;

[0079] The fifth microstrip line TL5 and the eighth microstrip line TL8 are both arranged perpendicular to the sixth microstrip line TL6;

[0080] The other end of the eighth microstrip line TL8 is electrically connected to one end of the tenth microstrip line TL10;

[0081] The eighth microstrip line TL8 is arranged perpendicular to the tenth microstrip line TL10;

[0082] The other end of the tenth microstrip line TL10 is electrically connected to the eleventh microstrip line TL11;

[0083] The ninth microstrip line TL9 is anti-parallel coupled to the tenth microstrip line TL10;

[0084] The third resonator (4-2-3) includes a twelfth microstrip line TL12, a thirteenth strip line TL13 and a fourteenth strip line TL14;

[0085] The twelfth microstrip line TL12 is electrically connected to one end of the thirteenth strip line TL13, and the other end of the thirteenth strip line TL13 is electrically connected to the fourteenth strip line TL14;

[0086] The other end of the thirteenth strip line TL13 is arranged perpendicular to the fourteenth strip line TL14;

[0087] The third strip line TL3 and the fourteenth strip line TL14 are both coupled and connected in parallel with the fifth microstrip line TL5;

[0088] The seventh microstrip line TL7 and the eighth microstrip line TL8 are both parallel to the fifth microstrip line TL5;

[0089] The first microstrip line TL1 and the second microstrip line TL2 are both coupled and connected in parallel with the fourth microstrip line TL4;

[0090] The twelfth microstrip line TL12 and the thirteenth microstrip line TL13 are both coupled and connected in parallel with the sixth microstrip line TL6 .

[0091] Combination Figure 1 , Figure 2 and Figure 3 The characteristic impedance range of the tuning line 4-1 is 30 to 50 ohms, and the electrical length range is 14° to 26°, which ensures that the optimal load impedance is flat within the passband, and the real and imaginary parts of the optimal load impedance are less affected by the characteristic impedance. For tuning lines with the same special impedance, as the electrical length increases, the real part of the optimal load impedance changes basically unchanged, but the imaginary part changes increase.

[0092] From the transmission line theory, we can get the input impedance Z of the bandpass filter: 1 , Figure 3 The optimal load impedance value after the tuning line of the output matching circuit of the present invention is changed with the frequency. It can be seen that the optimal load impedance Z L The real and imaginary parts of vary very little within the passband.

[0093] Combination Figure 1 and Figure 2 , the input port of the bandpass filter 4-2 is connected to the first resonator 4-2-1, and the output port of the bandpass filter 4-2 is connected to the third resonator 4-2-3;

[0094] By adjusting the position of the port connection line, the distance between the first resonator 4-2-1 and the second resonator 4-2-2, and the distance between the second resonator 4-2-2 and the third resonator 4-2-3, and the length of each resonator, the impedance matching and filtering characteristics are adjusted.

[0095] Combination Figure 1 , Figure 2 and Figure 4 The ninth microstrip line TL9 and the tenth microstrip line TL10 of the second resonator 4-2-2 are antiparallel coupled, and the third harmonic is suppressed on the basis of the resonator composed of the fourth microstrip line TL4, the fifth microstrip line TL5, and the sixth microstrip line TL6. The sum of the lengths of the fourth microstrip line TL4, the fifth microstrip line TL5, and the sixth microstrip line TL6 is λ g / 2.

[0096] To further suppress the second harmonic, an eleventh microstrip line TL11 is added at the end of the tenth microstrip line TL10. Figure 4 This is a result diagram of the resonance characteristics of the second resonator of the present invention. It can be seen that it has a good suppression effect on both the second and third harmonics.

[0097] The working principle of the filter power amplifier based on matched filter synthesis provided by the present invention is analyzed in detail below.

[0098] Combining the generalized filter synthesis theory, the polynomials E(s), F(s), and P(s) of the filter network with a dual port of 50 ohms are obtained. The relationship between the above polynomials is:

[0099] F 11 (s)·F 22 (s)-P 2 (s) / ε 2 =E(s)·E * (s) (1)

[0100] Among them, E(s), F(s) are N-order polynomials, N is the filter order, the roots of E(s) are all in the left half plane of the complex plane, P(s) is an N-TZ-order polynomial, TZ is the number of finite transmission zeros, E * (s) and the roots of E(s) are symmetric about the imaginary axis of the complex plane.

[0101] Combination Figure 2 , the input end of the bandpass filter 4-2 is a complex impedance Z 1 The output port has a real impedance of 50 ohms. 0 , adjust the characteristic impedance and electrical length of the tuning line 4-1 to obtain the optimal fundamental impedance Z L The variation in the passband is small, and Z is obtained from transmission line theory. 1 , introducing a more general scattering parameter, namely the power wave S parameter, to obtain a filter network that is conjugate matched with the external port. i (i=1,0) becomes Z i ′(i=1,0), and obtain the new scattering parameter matrix [S′]:

[0102] [S′]=[A] -1 ([S]-[Γ] + )([I]-[Γ][S]) -1 [A] + (2)

[0103] Among them, the superscript -1 and + Represent the inverse matrix and conjugate transposed matrix respectively, [I] is the unit matrix, [Γ] and [A] are diagonal matrices, and the diagonal elements are as follows:

[0104]

[0105] When the dual-port impedances are both real numbers, the power wave S parameter becomes a conventional S parameter. To facilitate the synthesis of the coupling matrix, the port impedance is often normalized, that is, Z′ i = 1, and the new scattering parameter matrix [S′] and its polynomials E′(s), F′(s) and P′(s) are obtained:

[0106]

[0107] Among them, E'(s), F'(s) are N-order polynomials, N is the filter order, the roots of E'(s) are all in the left half plane of the complex plane, P'(s) is an N-TZ-order polynomial, TZ is the number of finite transmission zeros, E' * The roots of (s) and E′(s) are symmetric about the imaginary axis of the complex plane.

[0108] In order to synthesize the coupling matrix of the bandpass filter 4-2 conveniently, [S′] is converted into an N-order admittance matrix [y]:

[0109]

[0110] Among them, y d is the element denominator of [y], y 12n ,y 21n and 22n For element molecules.

[0111] From the filter synthesis theory, the power wave [S′] and its admittance polynomial, the coupling matrix of the bandpass filter 4-2 can be obtained:

[0112]

[0113] Among them, M 11 , M 22 and M 33 Affecting the self-resonant frequency of the resonator, by adjusting the total length of the first resonator 4-2-1, the third resonator 4-2-3 and the fourth microstrip line TL4, the fifth microstrip line TL5, the sixth microstrip line TL6, the seventh microstrip line TL7, and the eighth microstrip line TL8 of the second resonator 4-2-2; M 12 and M 23 M is the coupling coefficient, and the coupling coefficient is changed by adjusting the distance between the first resonator 4-2-1 and the second resonator 4-2-2 and the distance between the second resonator 4-2-2 and the third resonator 4-2-3; S1 and M 3L The port Q value is changed by adjusting the tap line positions of the first resonator 4-2-1 and the third resonator 4-2-3 to change the corresponding port Q value. The filter that satisfies the above coupling matrix can achieve impedance matching and filtering characteristics. Figure 5 This is a diagram showing the S parameter results of the filter power amplifier based on matched filter synthesis of the present invention.

[0114] In this embodiment, the center frequency of the filter power amplifier based on matched filter synthesis provided by the present invention is 2.4 GHz and the bandwidth is 200 MHz. Figure 6 The output power and gain of the filter power amplifier based on matched filter synthesis according to the present invention vary with the input power. Figure 6As shown, in the working frequency band of 2.3-2.5GHz, when the output power is 36.1-36.6dBm, the gain is 11.1-11.6dB, indicating that the power amplifier has good filtering characteristics and power amplification characteristics.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A filter power amplifier based on matched filter synthesis, characterized in that: include: Input matching network, gate bias circuit, transistor and output matching network; The input matching network matches the wave source impedance to the transistor input impedance; The gate bias circuit provides a stable DC path for the transistor; The transistor amplifies the wave source signal; The output matching network matches the transistor output impedance to the load impedance and performs bandpass filtering at the same time; The output matching network includes a tuning line and a bandpass filter with fundamental wave matching, bandpass filtering and harmonic suppression effects; The tuning line is electrically connected to the bandpass filter; The bandpass filter comprises a first resonator, a second resonator and a third resonator; The first resonator and the second resonator are gap-coupled and connected; The second resonator and the third resonator are gap-coupled and connected; The first resonator includes a first microstrip line TL1, a second microstrip line TL2 and a third microstrip line TL3; The first microstrip line TL1 is electrically connected to one end of the second microstrip line TL2, and the other end of the second microstrip line TL2 is electrically connected to the third microstrip line TL3; The other end of the second microstrip line TL2 is arranged perpendicular to the third microstrip line TL3; The second resonator includes a fourth microstrip line TL4, a fifth microstrip line TL5, a sixth microstrip line TL6, a seventh microstrip line TL7, an eighth microstrip line TL8, a ninth microstrip line TL9, a tenth microstrip line TL10 and an eleventh microstrip line TL11; The fourth microstrip line TL4 is electrically connected to one end of the fifth microstrip line TL5 and one end of the seventh microstrip line TL7; The fifth microstrip line TL5 and the seventh microstrip line TL7 are both arranged perpendicular to the fourth microstrip line TL4; The other end of the fifth microstrip line TL5 is electrically connected to one end of the sixth microstrip line TL6; The other end of the seventh microstrip line TL7 is electrically connected to the ninth microstrip line TL9 and is arranged vertically; The other end of the fifth microstrip line TL5 and one end of the eighth microstrip line TL8 are electrically connected to the sixth microstrip line TL6; The fifth microstrip line TL5 and the eighth microstrip line TL8 are both arranged perpendicular to the sixth microstrip line TL6; The other end of the eighth microstrip line TL8 is electrically connected to one end of the tenth microstrip line TL10; The eighth microstrip line TL8 is arranged perpendicular to the tenth microstrip line TL10; The other end of the tenth microstrip line TL10 is electrically connected to the eleventh microstrip line TL11; The ninth microstrip line TL9 is anti-parallel coupled to the tenth microstrip line TL10; The third resonator includes a twelfth microstrip line TL12, a thirteenth strip line TL13 and a fourteenth strip line TL14; The twelfth microstrip line TL12 is electrically connected to one end of the thirteenth strip line TL13, and the other end of the thirteenth strip line TL13 is electrically connected to the fourteenth strip line TL14; The other end of the thirteenth strip line TL13 is arranged perpendicular to the fourteenth strip line TL14; The third strip line TL3 and the fourteenth strip line TL14 are both coupled and connected in parallel with the fifth microstrip line TL5; The seventh microstrip line TL7 and the eighth microstrip line TL8 are both parallel to the fifth microstrip line TL5; The first microstrip line TL1 and the second microstrip line TL2 are both coupled and connected in parallel with the fourth microstrip line TL4; The twelfth microstrip line TL12 and the thirteenth microstrip line TL13 are both coupled and connected in parallel with the sixth microstrip line TL6 .

2. A filter power amplifier based on matched filter synthesis according to claim 1, characterized in that: The ninth microstrip line TL9 and the tenth microstrip line TL10 are equal in length; The fourth microstrip line TL4 and the sixth microstrip line TL6 are equal in length; The fourth microstrip line TL4, the fifth microstrip line TL5 and the sixth microstrip line TL6 have the same width.

3. A filter power amplifier based on matched filter synthesis according to claim 2, characterized in that: The characteristic impedance of the tuning line ranges from 30 to 50 ohms and the electrical length ranges from arrive .

4. The filter power amplifier based on matched filter synthesis according to claim 1, characterized in that: The lengths of the first resonator and the third resonator are , is the resonant frequency and waveguide wavelength.

5. The filter power amplifier based on matched filter synthesis according to claim 1, characterized in that: The admittance matrix expression of the bandpass filter is as follows: （5） in, , for polynomial of order, is the filter order, for polynomial of order, is the number of finite transmission zeros, and The roots of are symmetric about the imaginary axis of the complex plane, for The denominator of the elements, , and For element molecules.

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