阅读说明：本技术 一种可重构超宽带功放谐波抑制电路 (Reconfigurable ultra-wideband power amplifier harmonic suppression circuit ) 是由 王超杰 周丽 王海龙 王安劳 揭海 卢子焱 于 2019-08-27 设计创作，主要内容包括：本发明涉及微波技术领域,公开了一种可重构超宽带功放谐波抑制电路。在基片上依次集成多个微带线传输线,相邻的微带线传输线之间并联第一FET开关管、第一开路短截线、第二FET开关管、第二开路短截线；当不需要进行谐波抑制时,使所有的第一FET开关管、第二FET开关管处于截止状态；当需要进行功率放大器的低频段谐波抑制时,使所有的第一FET开关管、第二FET开关管处于导通状态；当需要进行功率放大器的高频段谐波抑制时,使所有的第一FET开关管处于导通状态、所有的第二FET开关管处于截至状态。该方案可实现超宽带功率放大器带内谐波抑制及功能可重构；提供了一种结构简单、低插损、低功耗、小型化、可重构的超宽带功率放大器带内谐波抑制电路设计方法。(The invention relates to the technical field of microwaves and discloses a reconfigurable ultra-wideband power amplifier harmonic suppression circuit. A plurality of microstrip transmission lines are sequentially integrated on the substrate, and a first FET switch tube, a first open stub, a second FET switch tube and a second open stub are connected in parallel between adjacent microstrip transmission lines; when harmonic suppression is not needed, all the first FET switching tubes and all the second FET switching tubes are in a cut-off state; when the low-frequency harmonic suppression of the power amplifier is needed, all the first FET switch tubes and all the second FET switch tubes are in a conducting state; when high-band harmonic suppression of the power amplifier is required, all the first FET switching tubes are in a conducting state, and all the second FET switching tubes are in an off state. The scheme can realize in-band harmonic suppression and function reconfiguration of the ultra-wideband power amplifier; the design method of the in-band harmonic suppression circuit of the ultra-wideband power amplifier is simple in structure, low in insertion loss, low in power consumption, small in size and reconfigurable.)

1. A reconfigurable ultra-wideband power amplifier harmonic suppression circuit is characterized by comprising a substrate, FET (field effect transistor) switching tubes, open-circuit stubs and microstrip transmission lines, wherein a plurality of microstrip transmission lines are sequentially integrated on the substrate, and a first FET switching tube, a first open-circuit stub, a second FET switching tube and a second open-circuit stub are connected in parallel between adjacent microstrip transmission lines;

when harmonic suppression is not needed, all the first FET switching tubes and all the second FET switching tubes are in a cut-off state through control signals; when the low-frequency harmonic suppression of the power amplifier is needed, all the first FET switch tubes and the second FET switch tubes are in a conducting state through control signals; when high-band harmonic suppression of the power amplifier is required, all the first FET switching tubes are in a conducting state and all the second FET switching tubes are in an off state through control signals.

2. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the number of the microstrip transmission lines is determined by the width of a harmonic frequency band and the suppression degree.

3. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the substrate is fabricated from a GaN semiconductor material.

4. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the FET switch tube is fabricated from GaN semiconductor materials.

5. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the microstrip transmission line and the open stub are connected to a GaN semiconductor material substrate using a thin film gold plating process.

6. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the width of the microstrip transmission line is designed according to a characteristic impedance of 50 ohm, the length is determined by the requirement of the working frequency band of the harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier, a quarter of the wavelength of the central frequency of the corresponding working frequency band is taken as an initial length value, and then a final length value is obtained by combining simulation optimization.

7. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein the width of the open stub is designed according to a high impedance line, and the high impedance is that the characteristic impedance is higher than 100 ohm; the length is determined by the requirement of the working frequency band of the reconfigurable ultra-wideband power amplifier harmonic suppression circuit, one quarter of the wavelength of the central frequency of the corresponding trapped wave frequency band is taken as an initial length value, and then a final length value is obtained by combining simulation optimization.

8. The harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier of claim 1, wherein device parameters of the GaN-based FET switch tube are determined by the working frequency band of the harmonic suppression circuit, the power bearing requirements and the passband insertion loss requirements, and the control signal voltage is 0V/-20V-40V, wherein the FET switch tube is in a conducting state at 0V and is in a blocking state at-20V-40V.

Technical Field

The invention relates to the technical field of microwaves, in particular to a reconfigurable ultra-wideband power amplifier harmonic suppression circuit.

Background

Along with the development of system technology, the integrated requirements of each combat platform on radar, electronic combat and communication are more and more urgent, and particularly, the synthetic aperture is required to have the technical characteristics of simultaneous working of radar and electronic combat and has the ultra-wideband performance in a frequency domain. When the traditional discrete radar equipment or electronic warfare interference equipment is used for transmitting work, the second harmonic suppression degree of a final microwave power amplifier is low, and particularly the second harmonic suppression degree of the microwave power amplifier in ultra-wideband radar or electronic warfare equipment is only about 10 dBc. The ultra-wideband radar and the electronic warfare synthetic aperture share the transceiving antenna unit, the second harmonic of part of the transmitting frequency band is in the frequency band, and when the radar and the electronic warfare work simultaneously, the second harmonic in the transmitting band can influence the normal work of the receiving system. Therefore, the problem of low suppression degree of the second harmonic of the power amplifier in the ultra-wideband radar or the electronic warfare equipment must be solved. At present, the main technical approach for improving the second harmonic suppression degree of the power amplifier is a predistortion technology, the working principle is radio frequency cancellation, the working modes can be divided into analog predistortion and digital predistortion, but the two have the defects of relatively narrow frequency band and excessively complex structure, the circuit miniaturization is difficult to realize, and the two are not suitable for the application requirements of ultra-wideband radar and electronic warfare array systems.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the existing problems, a reconfigurable ultra-wideband power amplifier harmonic suppression circuit is provided.

The technical scheme adopted by the invention is as follows: a reconfigurable ultra-wideband power amplifier harmonic suppression circuit comprises a substrate, FET switch tubes, open-circuit stubs and microstrip transmission lines, wherein a plurality of microstrip transmission lines are sequentially integrated on the substrate, and a first FET switch tube, a first open-circuit stub, a second FET switch tube and a second open-circuit stub are connected in parallel between adjacent microstrip transmission lines;

when harmonic suppression is not needed, all the first FET switching tubes and all the second FET switching tubes are in a cut-off state through control signals; when the low-frequency harmonic suppression of the power amplifier is needed, all the first FET switch tubes and the second FET switch tubes are in a conducting state through control signals; when high-band harmonic suppression of the power amplifier is required, all the first FET switching tubes are in a conducting state and all the second FET switching tubes are in an off state through control signals.

Furthermore, the number of the microstrip transmission lines is determined by the width and the suppression degree of the harmonic frequency band.

Furthermore, the substrate is made of a GaN semiconductor material.

Furthermore, the FET switch tube is made of GaN semiconductor materials.

Furthermore, the microstrip transmission line and the open stub are connected to the GaN semiconductor material substrate by adopting a film gold plating process.

Furthermore, the width of the microstrip transmission line is designed according to 50 ohm characteristic impedance, the length is determined by the requirement of the working frequency band of the reconfigurable ultra-wideband power amplifier harmonic suppression circuit, one quarter of the wavelength of the central frequency of the corresponding working frequency band is generally taken as an initial length value, and then a final length value is obtained by combining simulation optimization.

Furthermore, the width of the open-circuit stub is designed according to a high-impedance line, and the high impedance means that the characteristic impedance is higher than 100 ohm; the length is determined by the requirement of the working frequency band of the reconfigurable ultra-wideband power amplifier harmonic suppression circuit, one quarter of the wavelength of the central frequency of the corresponding trapped wave frequency band is taken as an initial length value, and then a final length value is obtained by combining simulation optimization.

Furthermore, the device parameters of the GaN-based FET switch tube are determined by the working frequency band of the harmonic suppression circuit, the bearing power and the requirements of passband insertion loss, and the voltage of the control signal is 0V/-20V-40V, wherein the FET switch tube is in a conducting state at 0V and is in a stopping state at-20V-40V.

Compared with the prior art, the beneficial effects of adopting the technical scheme are as follows: by adopting the technical scheme of the invention, in-band harmonic suppression and function reconfiguration of the ultra-wideband power amplifier can be realized; compared with the prior art, the invention provides the design method of the in-band harmonic suppression circuit of the ultra-wideband power amplifier, which has the advantages of simple structure, low insertion loss, low power consumption, miniaturization and reconfigurability.

Drawings

FIG. 1 is a schematic diagram of a structure of a harmonic suppression circuit of the reconfigurable ultra-wideband power amplifier.

The labels in the figure are: w₀、W₁Respectively microstrip transmission line width and open stub width, L₀Is the length of microstrip transmission line, L₁、L₂、L₃、L₄、L₅、L₆Respectively corresponding to the lengths of the parallel open-circuit stubs.

FIG. 2 shows a basic unit of a reconfigurable ultra-wideband power amplifier harmonic suppression circuit structure.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The invention provides a reconfigurable ultra-wideband power amplifier harmonic suppression circuit which mainly comprises a substrate, an FET switch tube, an open-circuit stub and a microstrip transmission line. As shown in fig. 1, 4 microstrip transmission lines are taken as an example to explain, a microstrip transmission line 1, a microstrip transmission line 2, a microstrip transmission line 3, and a microstrip transmission line 4 are integrated on a substrate 1 of GaN semiconductor material, a GaN-based FET switch tube 1, an open stub 1, a GaN-based FET switch tube 2, and an open stub 2 are connected in parallel between the microstrip transmission lines 1 and 2, a GaN-based FET switch tube 3, an open stub 3, a GaN-based FET switch tube 4, and an open stub 4 are connected in parallel between the microstrip transmission lines 2 and 3, and a GaN-based FET switch tube 5, an open stub 5, a GaN-based FET switch tube 6, and an open stub 6 are connected in parallel between the microstrip transmission lines 3 and 4.

Preferably, the number of the microstrip transmission line, the GaN-based FET switch tube, and the open stub is determined by the width of the harmonic band and the suppression degree, and may be determined by cascading the basic units shown in fig. 2.

Preferably, the microstrip transmission lines 1-4 and the open-circuit stubs 1-6 are connected to the GaN semiconductor material substrate by a film gold plating process.

Preferably, the width of the microstrip transmission lines 1-4 is designed according to 50 ohm characteristic impedance, and the length is determined by the requirement of the working frequency band of the reconfigurable ultra-wideband power amplifier harmonic suppression circuit.

Preferably, the width of the open-circuit stub lines 1-6 is designed according to a high-impedance line, and the length is determined by the requirement of the working frequency band of the reconfigurable ultra-wideband power amplifier harmonic suppression circuit.

Preferably, the device parameters of the GaN-based FET switching tubes 1-6 are determined by the working frequency band of the harmonic suppression circuit, the bearing power and the requirements of passband insertion loss, and the control signal voltage is 0V/-20V-40V, wherein the FET switching tube is in a conducting state at 0V and is in a stopping state at-28V-40V.

The main path microstrip transmission line plays a role in connecting with a power amplifier externally, and meanwhile, low-difference-loss transmission of passband microwave power signals is realized; the open-circuit stub plays a role in harmonic suppression, and the length and width dimensions of the open-circuit stub determine a harmonic suppression frequency band; the GaN-based FET switching tube has the function of selecting the harmonic suppression circuit, and is controlled to be in a conducting or cut-off working state through a control signal, so that the reconstruction of the ultra-wideband power amplifier harmonic suppression circuit is realized.

When harmonic suppression is not needed, all the GaN-based FET switching tubes 1-6 are in a cut-off state through control signals, and the signals are normally output through the microstrip transmission line; when the low-frequency harmonic suppression of the power amplifier is needed, the GaN-based FET switching tubes 1-6 are all in a conducting state through control signals, the low-frequency signals are normally output, and the second harmonic frequency band of the low-frequency signals is suppressed; when the high-frequency band harmonic suppression of the power amplifier is needed, the GaN-based FET switch tube 1, the GaN-based FET switch tube 3 and the GaN-based FET switch tube 5 are in a conducting state through a control signal, the GaN-based FET switch tube 2, the GaN-based FET switch tube 4 and the GaN-based FET switch tube 6 are in a stopping state, the high-frequency band signal is normally output, and the second harmonic frequency band of the high-frequency band signal is suppressed.

The circuit is tested and verified in a 6-18 GHz ultra-wideband power amplifier, the ultra-wideband power amplifier harmonic suppression circuit can work in modes of microwave direct connection 6-18 GHz, harmonic suppression and the like through a control signal, and the harmonic suppression mode can be selected in two working modes of a harmonic suppression frequency band 12-15 GHz (corresponding to a passband frequency band 6-7.5 GHz) and a harmonic suppression frequency band 14-20 GHz (corresponding to a passband frequency band 7-10 GHz). The insertion loss is less than 0.2dB when the harmonic suppression type filter works in a straight-through mode, the insertion loss of a pass band is less than 0.7dB when the harmonic suppression type filter works in a harmonic suppression mode, and the corresponding harmonic suppression degree is greater than 30 dBc.

The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed. Those skilled in the art to which the invention pertains will appreciate that insubstantial changes or modifications can be made without departing from the spirit of the invention as defined by the appended claims.