WO2023093350A1

WO2023093350A1 - Radio frequency power amplifier and short message communication system

Info

Publication number: WO2023093350A1
Application number: PCT/CN2022/125274
Authority: WO
Inventors: 许靓; 郭嘉帅
Original assignee: 深圳飞骧科技股份有限公司
Priority date: 2021-11-24
Filing date: 2022-10-14
Publication date: 2023-06-01
Also published as: CN114172468A

Abstract

Provided in the present invention is a radio frequency power amplifier. The radio frequency power amplifier comprises a front-stage power amplifier, which is used for amplifying a signal of an input end, and then outputting a single-ended signal; a first helix balun, which is used for converting the single-ended signal of the front-stage power amplifier into a differential signal, and realizing equal power division; a final-stage power amplification unit, which is used for amplifying the differential signal which is output by the first helix balun, and then outputting the amplified differential signal; a second helix balun, which is used for synthesizing the differential signal which is output by the final-stage power amplification unit, and then outputting the synthesized differential signal; a balun tuning capacitor unit, which is used for adjusting the output impedance of the front-stage power amplifier and the output impedance of the final-stage power amplifier; and an output matching network, which is used for realizing impedance matching of a signal which is output by the second helix balun, and then outputting the signal. Further provided in the present invention is a short message communication system. Compared with the prior art, the radio frequency power amplifier and the short message communication system in the present invention have a high output saturation power and a strong harmonic suppression capability.

Description

RF Power Amplifier and Short Message Communication System

technical field

The invention relates to the technical field of wireless communication radio frequency chip design, in particular to a radio frequency power amplifier suitable for a short message communication system and a short message communication system.

Background technique

The short message communication in the satellite navigation system is mainly used in areas that cannot be covered by ordinary mobile communication signals (such as uninhabited areas, deserts, oceans, polar regions, etc.) or when the communication base station is damaged (such as earthquakes, floods, typhoons, etc.) , because the communication environment is more harsh and complex, and the communication distance between the navigation terminal and the satellite is longer than that of the cellular mobile network, the accuracy and stability of the communication system are particularly critical.

When the satellite navigation ground terminal is working normally, it can directly carry out two-way information transmission with the navigation satellite and the navigation ground monitoring station through the satellite signal. The farther the distance, as the key component of the RF front-end, the RF power amplifier needs to output higher saturated power, and the RF power amplifier usually works in the non-linear region at high power output, which will generate a series of harmonic components. Harmonic suppression The capability becomes worse, and its own ability to suppress harmonics will become an important indicator for judging its overall performance.

Contents of the invention

Aiming at the deficiencies of the above related technologies, the present invention proposes a radio frequency power amplifier and a short message communication system with high output saturation power and strong harmonic suppression capability.

In order to solve the above technical problems, an embodiment of the present invention provides a radio frequency power amplifier, including:

input terminal;

A pre-stage power amplifier, the input of the pre-stage power amplifier is connected to the input end, and is used to amplify the signal at the input end and output a single-ended signal;

The first helical balun is used to convert the single-ended signal of the pre-stage power amplifier into a differential signal and realize power equalization; the first end of the primary coil of the first helical balun is connected to the pre-stage power the output of the amplifier, the second end of the primary coil of the first helical balun is respectively connected to the first supply voltage and ground;

The final power amplifying unit is used to amplify the differential signal output by the first helical balun and then output it, which includes a first power amplifier and a second power amplifier, and the input of the first power amplifier is connected to the the first end of the secondary coil of the first helical balun, the input of the second power amplifier is connected to the second end of the secondary coil of the first helical balun;

The second helical balun is used for synthesizing the differential signals output by the final stage power amplifying unit and then outputting, the first end of the primary coil of the second helical balun is connected to the first power amplifier output, the second end of the primary coil of the second helical balun is connected to the output of the second power amplifier; the middle tap end of the primary coil of the second helical balun is connected to a second power supply;

A balun tuning capacitor unit, the balun tuning circuit unit includes a first balun tuning capacitor unit connected to the first helical balun and a second balun tuning connected to the second helical balun a capacitor unit, used to adjust the output impedance of the pre-stage power amplifier and the final-stage power amplifier;

The output matching network is used to output the signal output by the second spiral balun after impedance matching, which includes a first series resonant circuit, a second series resonant circuit, a first low-pass matching circuit, a second series resonant circuit connected in sequence a low-pass matching circuit, a third low-pass matching circuit, and a band-stop matching network; and,

an output terminal, the output terminal is connected to the output of the output matching network.

Preferably, the radio frequency power amplifier is composed of a radio frequency chip unit and a substrate assembly; the output terminal, the pre-stage power amplifier, the first helical balun, the first balun tuning capacitor unit, the The final power amplifying unit is integrated in the radio frequency chip unit, and the second spiral balun, the second balun tuning capacitor unit, the output matching network, and the output terminal are all formed on the substrate .

Preferably, the first balun tuning capacitor unit includes a first tuning capacitor, a second tuning capacitor, a third tuning capacitor and a fourth tuning capacitor; the first end of the primary coil of the first helical balun is also passed through The first tuning capacitor is connected in series to the ground; the second end of the primary coil of the first helical balun is connected to the ground after the second tuning capacitor is connected in series; the second end of the first helical balun The middle tap end of the primary coil is connected to the ground after being connected in series with the third tuning capacitor; the fourth tuning capacitor is connected in parallel with the primary coil of the second helical balun.

Preferably, the first tuning capacitor, the second tuning capacitor, the third tuning capacitor and the fourth tuning capacitor are on-chip STACK capacitors or MIM capacitors.

Preferably, the second balun tuning capacitor unit includes a fifth tuning capacitor, a sixth tuning capacitor, a seventh tuning capacitor and an eighth tuning capacitor; the middle tap end of the primary coil of the second helical balun is also passed The fifth tuning capacitor is connected in series to the ground; the second end of the secondary coil of the second helix balun is connected to the ground after the sixth tuning capacitor is connected in series; the seventh tuning capacitor and the The eighth tuning capacitors are respectively connected in parallel with the secondary coils of the second helical baluns.

Preferably, the first series resonant circuit includes the seventh resonant capacitor and the first resonant inductance connected in series, and one end of the first series resonant circuit is connected to the second coil of the secondary coil of the second spiral balun. One end, the other end of the first series resonant circuit is connected to ground; the structure of the second series resonant circuit is the same as that of the first series resonant circuit.

Preferably, the first low-pass matching circuit includes a first inductance, a first capacitor and a first matching inductance, and the first end of the first inductance is connected to the secondary coil of the second helical balun as an input The first end of the first inductor, the second end of the first inductor is used as an output, the first end of the first capacitor is connected to the second end of the first inductor, and the second end of the first capacitor is connected to the The first end of the first matching inductance, the second end of the first matching inductance is connected to ground; the second low-pass matching circuit and the third low-pass matching circuit are both connected to the first low-pass matching circuit The structures are the same, the input of the second low-pass matching circuit is connected to the output of the first low-pass matching circuit, and the input of the third low-pass matching circuit is connected to the output of the second low-pass matching circuit.

Preferably, the band-stop matching network includes a fourth capacitor and a fourth inductor connected in parallel, the input of the band-stop matching network is connected to the output of the third low-pass matching circuit, and the output of the band-stop matching network connected to the output.

Preferably, the first inductance, the second inductance, the third inductance, the first matching inductance, the second matching inductance, the third matching inductance, the first resonance inductance and the second resonance The inductors are all formed in the form of SMT, wire-wound inductors or IPD.

An embodiment of the present invention also provides a short message communication system, including the radio frequency power amplifier provided by the embodiment of the present invention.

Compared with the prior art, the RF power amplifier and the short message communication system of the present invention include a pre-stage power amplifier, which is used to amplify the input signal and output a single-ended signal; the first helical balun is used to amplify the input signal; The single-ended signal of the pre-stage power amplifier is converted into two differential signals; the final power amplifying unit is used to amplify the differential signal output by the first helical balun and output it; the second helical balun is used to The differential signal output by the final stage power amplifying unit is synthesized and then output; the balun tuning capacitor unit is used to adjust the output impedance of the pre-stage power amplifier and the final stage power amplifier; the output matching network is used to combine The signal output by the second helical balun is output after impedance matching. Through the two-stage power amplification structure of the above structure and the differential conversion of the helical balun, a higher saturated power output is effectively realized and the suppression of even harmonics is strengthened; at the same time, through the balun tuning capacitor unit in the above structure and the output matching The structural setting of the network more effectively realizes the matching of the output impedance and the suppression of the second-order and third-order harmonics, thereby achieving a better harmonic suppression effect.

Description of drawings

The present invention will be described in detail below in conjunction with the accompanying drawings. The content of the above or other aspects of the present invention will become clearer and easier to understand through the detailed description in conjunction with the following drawings. In the attached picture:

Fig. 1 is the circuit structural frame diagram of the radio frequency power amplifier provided by the embodiment of the present invention;

Fig. 2 is the S energy number simulation result graph of the radio frequency power amplifier provided by the embodiment of the present invention;

Fig. 3 is a graph of simulation results of output power of a radio frequency power amplifier provided by an embodiment of the present invention.

Detailed ways

Specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

The specific implementations/examples described here are specific specific implementations of the present invention, and are used to illustrate the concept of the present invention. limit. In addition to the embodiments described here, those skilled in the art can also adopt other obvious technical solutions based on the claims of the application and the contents disclosed in the description, and these technical solutions include adopting any obvious changes made to the embodiments described here. The replacement and modified technical solutions are all within the protection scope of the present invention.

The following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the present invention can be practiced. The directional terms mentioned in the present invention, such as up, down, front, back, left, right, inside, outside, side, etc., are only directions referring to the attached drawings. Therefore, the directional terms used are used to illustrate and understand the present invention, but not to limit the present invention.

Please refer to Fig. 1, the embodiment of the present invention provides a radio frequency power amplifier 100, including: input terminal RFin, input matching network 1, pre-stage power amplifier DA1, first spiral balun TF1, final power amplifying unit 2. The second spiral balun TF2, the balun tuning capacitor unit, the output matching network 3 and the output terminal RFout.

The input terminal RFin is used for receiving radio frequency signals.

The input of the pre-stage power amplifier DA1 is connected to the input terminal RFin, and is used for amplifying the radio frequency signal at the input terminal RFin to output a single-ended signal. Of course, the input matching network 1 can also be connected in series between the input of the pre-stage power amplifier DA1 and the input terminal RFin to achieve matching of input impedance, such as connecting a filter in series, the input matching mentioned in this embodiment Network 1 is mainly used for 50-ohm matching at the input end of the RF power amplifier.

The first helical balun TF1 is used to convert the single-ended signal amplified by the pre-stage power amplifier DA1 into two differential signals and realize power equalization; the first coil of the primary coil of the first helical balun TF1 One end is connected to the output of the pre-stage power amplifier DA1, and the second end of the primary coil of the first helical balun TF1 is respectively connected to the first power supply voltage VCC1 and ground.

The final power amplifying unit 2 is used to amplify the differential signal output by the first spiral balun TF1 and then output it, which includes a first power amplifier PA2_1 and a first power amplifier PA2_2, and the first power amplifier PA2_1 The input of the first helical balun TF1 is connected to the first end of the secondary coil, and the input of the first power amplifier PA2_2 is connected to the second end of the secondary coil of the first helical balun TF1 .

The second helical balun TF2 is used for synthesizing the differential signals output by the final stage power amplifying unit 2 and outputting them. The first end of the primary coil of the second helical balun TF2 is connected to the output of the first power amplifier PA2_1, and the second end of the primary coil of the second helical balun TF2 is connected to the first The output of the power amplifier PA2_2; the middle tap end of the primary coil of the second helix balun TF2 is connected to the second power supply VCC2.

The balun tuning circuit unit includes a first balun tuning capacitor unit connected to the first helical balun TF1 and a second balun tuning capacitor unit connected to the second helical balun TF2, respectively. It is used to adjust the output impedance of the pre-stage power amplifier DA1 and the final-stage power amplifier 2 to achieve a better harmonic suppression effect.

Specifically, the first balun tuning capacitor unit includes a first tuning capacitor C01 , a second tuning capacitor C02 , a third tuning capacitor C03 and a fourth tuning capacitor C04 .

The first end of the primary coil of the first helical balun TF1 is also connected to ground through the first tuning capacitor C01 in series; the second end of the primary coil of the first helical balun TF1 is connected in series The second tuning capacitor C02 is connected to the ground; the middle tap end of the secondary coil of the first spiral balun TF1 is connected to the ground after the third tuning capacitor C03 is connected in series; the fourth tuning capacitor C04 and The primary coils of the second helix balun TF2 are connected in parallel.

The second balun tuning capacitor unit includes a fifth tuning capacitor C05 , a sixth tuning capacitor C06 , a seventh tuning capacitor Ct1 and an eighth tuning capacitor Ct2 .

The middle tap end of the primary coil of the second helix balun TF2 is also connected to ground after connecting the fifth tuning capacitor C05 in series; the second end of the secondary coil of the second helix balun TF2 is connected in series The sixth tuning capacitor C06 is then connected to ground; the seventh tuning capacitor Ct1 and the eighth tuning capacitor Ct2 are respectively connected in parallel with the secondary coil of the second helix balun TF2.

The output matching network 3 is used to output the signal output by the second spiral balun TF2 after impedance matching, which includes a first series resonant circuit 31, a second series resonant circuit 32, a first low-pass circuit connected in sequence A matching circuit 33 , a second low-pass matching circuit 34 , a third low-pass matching circuit 35 and a band-stop matching network 36 .

Specifically, the first series resonant circuit 31 includes the seventh resonant capacitor Ct1 and the first resonant inductance Lt1 connected in series, and one end of the first series resonant circuit 31 is connected to the second spiral balun TF2 The first end of the secondary coil and the other end of the first series resonant circuit 31 are connected to ground.

The structure of the second series resonant circuit 32 is the same as that of the first series resonant circuit 31 . Specifically, it includes the eighth resonant capacitor Ct2 and the second resonant inductance Lt2 connected in series, and one end of the second series resonant circuit 32 is connected to the first end of the secondary coil of the second spiral balun TF2, so The other end of the second series resonant circuit 32 is connected to ground.

It should be noted that the seventh resonant capacitor Ct1 and the eighth resonant capacitor Ct2 not only serve as a part of the second balun tuning capacitor unit, but also serve as a part of the second series resonant circuit 32, reducing the number of components to achieve great performance optimization.

The first low-pass matching circuit 33 includes a first inductor L1, a first capacitor C1 and a first matching inductor L01.

The first end of the first inductor L1 is used as an input and connected to the first end of the secondary coil of the second helix balun TF2, and the second end of the first inductor L1 is used as an output. The first end of the first capacitor C1 is connected to the second end of the first inductor L1, and the second end of the first capacitor C1 is connected to the first end of the first matching inductor L01; A second terminal of a matching inductor L01 is connected to ground.

Both the second low-pass matching circuit 34 and the third low-pass matching circuit 35 have the same structure as the first low-pass matching circuit 33 , thereby jointly forming a three-stage low-pass matching network.

The input of the second low-pass matching circuit 34 is connected to the output of the first low-pass matching circuit 33 . Specifically, the second low-pass matching circuit 34 includes a second inductor L2, a second capacitor C2 and a second matching inductor L02.

The first terminal of the second inductor L2 is connected to the second terminal of the first inductor L1 as an input, and the second terminal of the second inductor L2 is used as an output. The first end of the second capacitor C2 is connected to the second end of the second inductor L2, and the second end of the second capacitor C2 is connected to the first end of the second matching inductor L02; The second ends of the two matching inductors L02 are connected to the ground.

The input of the third low-pass matching circuit 35 is connected to the output of the second low-pass matching 34 circuit. Specifically, the third low-pass matching circuit 35 includes a third inductor L3, a third capacitor C3 and a third matching inductor L03.

The first terminal of the third inductor L3 is used as an input and connected to the second terminal of the second inductor L2, and the second terminal of the third inductor L3 is used as an output. The first terminal of the third capacitor C3 is connected to the second terminal of the third inductor L3, and the second terminal of the third capacitor C3 is connected to the first terminal of the third matching inductor L03; The second end of the three-matching inductor L03 is connected to the ground.

The band-stop matching network 36 is a parallel resonant circuit in this embodiment, including a fourth capacitor C4 and a fourth inductor L4 connected in parallel, and the input of the band-stop matching network 36 is connected to the third low-pass matching circuit The output of 35 is connected to the second end of the third inductor L3, and the output of the band-stop matching network 36 is connected to the output terminal RFout.

The output terminal RFout is connected to the output of the output matching network 3 , that is, to the output of the band-stop matching network 36 .

In this embodiment, the radio frequency power amplifier 100 is composed of a radio frequency chip unit HBT DIE and a laminate substrate.

Wherein, the output terminal RFout, the pre-stage power amplifier DA1, the first spiral balun TF1, the first balun tuning capacitor unit, and the final power amplifier unit are all integrated in the radio frequency chip Unit HBT DIE, the second spiral balun TF2, the second balun tuning capacitor unit, the output matching network 3, and the output terminal RFout are all formed on the substrate Laminate.

In this embodiment, the implementation of the second tuning capacitor C02, the third tuning capacitor C03 and the fourth tuning capacitor C04 is formed as an on-chip STACK capacitor or MIM capacitor, which can effectively save the occupied area on the radio frequency chip unit HBT DIE, Achieve miniaturization.

The first inductance L1, the second inductance L2, the third inductance L3, the first matching inductance L01, the second matching inductance L02, the third matching inductance L03, the first resonance inductance Lt1 And the second resonant inductance Lt2 is formed by SMT form, wire wound inductance form or IPD form.

The first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C3, the seventh resonant capacitor Ct1, and the eighth resonant capacitor Ct2 are all in the form of SMT or IPD form.

In the radio frequency power amplifier 100 of the present invention, in terms of harmonic suppression, the series resonant circuit (Trap) formed by the seventh resonant capacitor Ct1 and the first resonant inductance Lt1, the eighth resonant capacitor Ct2 and the second resonant inductance Lt2 is mainly for four Harmonics above the first order are suppressed. The series resonant circuit (Trap) formed by the first capacitor C1 and the first matching inductor L01 mainly suppresses the second order harmonic. The series resonant circuit (Trap) formed by the second capacitor C2 and the second matching inductor L02 mainly suppresses the second order harmonic. The series resonant circuit (Trap) formed by the third capacitor C3 and the third matching inductor L03 mainly suppresses the third-order harmonic. The parallel resonant circuit (Tank) formed by the fourth capacitor C4 and the fourth inductor L4 mainly suppresses the third-order harmonic.

In addition, the second helix balun TF2 not only realizes power synthesis of differential signals, but also acts as a DC blocking capacitor, which can reduce the number of SMDs in the module and save costs.

In the differential power amplifier structure realized by the first helical balun TF1 and the second helical balun TF2, in addition to the function of realizing power synthesis and improving the output power of the RF power amplifier, the differential structure itself can also Realize the function of strengthening the suppression of even-order harmonics, and further improve the harmonic suppression effect.

The tuning capacitors C01, C02, and C03 of the first helix balun TF1 on the chip can adjust the output impedance of the pre-amplifier DA1; in addition, the fourth capacitor C04 on the chip and the capacitors C05, C06, Ct1, and Ct2 outside the chip can The output impedances of the first power amplifier PA2_1 and the second power amplifier PA2_2 of the final power amplifier unit are adjusted.

The specific harmonic suppression effect and power amplification effect are shown in Fig. 2-3. It can be seen from the simulation results in Fig. 2 that, compared with the traditional structure, the circuit structure of the radio frequency amplifier of the present invention has a higher suppression ability for each order of harmonics. It can be seen from the simulation results in FIG. 3 that while the circuit structure of the radio frequency amplifier of the present invention has a higher harmonic suppression capability, its saturation power has also been significantly improved compared with the traditional structure.

An embodiment of the present invention also provides a short message communication system, including the radio frequency power amplifier 100 provided in the embodiment of the present invention.

Compared with the prior art, the radio frequency power amplifier and the short message communication system of the present invention include the pre-stage power amplifier DA1, which is used to amplify the input signal and output a single-ended signal; the first spiral balun TF1 uses It is used to convert the single-ended signal of the pre-stage power amplifier DA1 into two differential signals; the final power amplifying unit is used to amplify the differential signal output by the first helical balun TF1 and then output it; the second helical balun Lun TF2, used for synthesizing the differential signals output by the final stage power amplifying unit and then outputting; Balun tuning capacitor unit, used for adjusting the output impedance of the pre-stage power amplifier DA1 and the final stage power amplifier; output The matching network 3 is configured to output the signal output by the second helix balun TF2 after impedance matching. Through the two-stage power amplification structure of the above structure and the differential conversion of the helical balun, a higher saturated power output is effectively realized and the suppression of even harmonics is strengthened; at the same time, through the balun tuning capacitor unit in the above structure and the output matching The structural setting of the network 3 more effectively realizes the matching of the output impedance and the suppression of the second-order and third-order harmonics, thereby achieving a better harmonic suppression effect.

It should be noted that the various embodiments described above with reference to the accompanying drawings are only used to illustrate the present invention rather than limit the scope of the present invention. Those of ordinary skill in the art should understand that without departing from the spirit and scope of the present invention Any modifications or equivalent replacements made to the present invention shall fall within the scope of the present invention. Further, words appearing in the singular include the plural and vice versa unless the context otherwise requires. Additionally, all or a portion of any embodiment may be utilized with all or a portion of any other embodiment, unless stated otherwise.

Claims

A kind of radio frequency power amplifier, it is characterized in that, described radio frequency power amplifier comprises

input terminal;

A pre-stage power amplifier, the input of the pre-stage power amplifier is connected to the input end, and is used to amplify the signal at the input end and output a single-ended signal;

The first helical balun is used to convert the single-ended signal of the pre-stage power amplifier into a differential signal and realize power equalization; the first end of the primary coil of the first helical balun is connected to the front The output of the stage power amplifier, the second end of the primary coil of the first helical balun is respectively connected to the first power supply voltage and ground;

The final power amplifying unit is used to amplify the differential signal output by the first helical balun and then output it, which includes a first power amplifier and a second power amplifier, and the input of the first power amplifier is connected to the the first end of the secondary coil of the first helical balun, the input of the second power amplifier is connected to the second end of the secondary coil of the first helical balun;

The second helical balun is used for synthesizing the differential signals output by the final stage power amplifying unit and then outputting, the first end of the primary coil of the second helical balun is connected to the first power amplifier output, the second end of the primary coil of the second helical balun is connected to the output of the second power amplifier; the middle tap end of the primary coil of the second helical balun is connected to a second power supply;

A balun tuning capacitor unit, the balun tuning circuit unit includes a first balun tuning capacitor unit connected to the first helical balun and a second balun tuning connected to the second helical balun a capacitor unit, used to adjust the output impedance of the pre-stage power amplifier and the final-stage power amplifier;

The output matching network is used to output the signal output by the second spiral balun after impedance matching, which includes a first series resonant circuit, a second series resonant circuit, a first low-pass matching circuit, a second series resonant circuit connected in sequence a low-pass matching circuit, a third low-pass matching circuit, and a band-stop matching network; and,

an output terminal, the output terminal is connected to the output of the output matching network.
The radio frequency power amplifier according to claim 1, wherein the radio frequency power amplifier is composed of a radio frequency chip unit and a substrate assembly; the output terminal, the pre-stage power amplifier, the first helical balun, The first balun tuning capacitor unit and the final power amplifying unit are integrated in the radio frequency chip unit, the second spiral balun, the second balun tuning capacitor unit, and the output matching network , the output terminals are all formed on the substrate.
The radio frequency power amplifier according to claim 1, wherein the first balun tuning capacitor unit includes a first tuning capacitor, a second tuning capacitor, a third tuning capacitor and a fourth tuning capacitor; the first spiral The first end of the primary coil of the wire balun is also connected to ground by connecting the first tuning capacitor in series; the second end of the primary coil of the first spiral balun is connected to the ground by connecting the second tuning capacitor in series Grounding; the middle tap end of the secondary coil of the first helical balun is connected to the ground after being connected in series with the third tuning capacitor; the fourth tuning capacitor is connected in parallel with the primary coil of the second helical balun connect.
The radio frequency power amplifier according to claim 3, wherein the first tuning capacitor, the second tuning capacitor, the third tuning capacitor and the fourth tuning capacitor are on-chip STACK capacitors or MIM capacitors.
The radio frequency power amplifier according to claim 1, wherein the second balun tuning capacitor unit includes a fifth tuning capacitor, a sixth tuning capacitor, a seventh tuning capacitor and an eighth tuning capacitor; the second spiral The middle tap end of the primary coil of the wire balun is also connected to ground by connecting the fifth tuning capacitor in series; the second end of the secondary coil of the second spiral balun is connected to the ground by connecting the sixth tuning capacitor in series to ground; the seventh tuning capacitor and the eighth tuning capacitor are respectively connected in parallel with the secondary coil of the second helical balun.
The radio frequency power amplifier according to claim 5, wherein the first series resonant circuit includes the seventh resonant capacitor and the first resonant inductor connected in series, and one end of the first series resonant circuit is connected to the The first end of the secondary coil of the second helical balun and the other end of the first series resonant circuit are connected to ground; the structure of the second series resonant circuit is the same as that of the first series resonant circuit.
The radio frequency power amplifier according to claim 6, wherein the first low-pass matching circuit comprises a first inductor, a first capacitor and a first matching inductor, and the first end of the first inductor is connected as an input to the first end of the secondary coil of the second helix balun, the second end of the first inductor is used as an output, the first end of the first capacitor is connected to the second end of the first inductor, The second end of the first capacitor is connected to the first end of the first matching inductor, and the second end of the first matching inductor is connected to ground; the second low-pass matching circuit and the third low-pass matching circuit All circuits have the same structure as the first low-pass matching circuit, the input of the second low-pass matching circuit is connected to the output of the first low-pass matching circuit, and the input of the third low-pass matching circuit is connected to output of the second low-pass matching circuit.
The radio frequency power amplifier according to claim 6, wherein the band-stop matching network includes a fourth capacitor and a fourth inductor connected in parallel, and the input of the band-stop matching network is connected to the third low-pass matching The output of the circuit, the output of the band-stop matching network is connected to the output terminal.
The radio frequency power amplifier according to claim 7, characterized in that, the first inductor, the second inductor, the third inductor, the first matching inductor, the second matching inductor, the first The three matching inductances, the first resonant inductance and the second resonant inductance are all formed in the form of SMT or wire wound inductance or IPD.
A short message communication system, characterized by comprising the radio frequency power amplifier according to any one of claims 1-9.