Multi-octave broadband power amplifier

Abstract

The utility model discloses a multi-octave broadband power amplifier which comprises a radio frequency amplification unit, a control unit, a filter unit, a detection unit and a heat dissipation unit. The radio frequency amplification unit receives a radio frequency signal and transmits the radio frequency signal to the filtering unit after power amplification, and the filtering unit filters harmonic waves in the amplified radio frequency signal and transmits the radio frequency signal to the detection unit for coupling and detection and then outputs the radio frequency signal; the control unit receives an external control instruction signal and then transmits the control instruction signal to the radio frequency amplification unit for control. And the heat dissipation unit is respectively connected with the radio frequency amplification unit and the control unit and performs temperature control. According to the utility model, the problems of single function and narrow frequency band coverage range of a radio station in the prior art are solved, and multi-function and multi-octave coverage of the radio station is realized; meanwhile, the device has the advantages of being small in size, convenient to operate and the like, manufacturing cost is reduced to a great extent, and time cost is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of radio frequency power amplification, in particular to a multi-octave broadband power amplifier. Background Art

[0002] Broadband power amplifiers are key components in the RF front end and are widely used in software radio stations. They are used in ultra-short wave, short wave, VHF, and UHF frequency band radio stations. The functions implemented by broadband power amplifiers in different frequency bands are also different, including data transmission, voice communication, graphic information, etc. The frequency bandwidth covered is basically within one octave. With the development of the industry, radio stations need to realize more and more functions, and traditional single-function radio stations can no longer meet the needs. In order to achieve multi-functional uses, several power amplifiers with different functions are often integrated together. Time-sharing and frequency-division work. Although this method can meet the needs, the implementation of the solution is relatively complicated and the cost is relatively expensive. The radio station is large in size and not conducive to operation. Utility Model Content

[0003] In order to solve the above problems, the utility model provides a multi-octave broadband power amplifier, including an amplification unit, a control unit, a filtering unit, a detection unit, and a heat dissipation unit;

[0004] After receiving the external control signal, the control unit transmits the control instruction to the amplifying unit; the amplifying unit receives the radio frequency signal and the control instruction of the control unit and transmits it to the filtering unit after power amplification; the filtering unit filters out the harmonics in the amplified radio frequency signal and transmits it to the detection unit for coupling and detection, and then outputs it to the control unit and the outside respectively; the two ends of the heat dissipation unit are respectively connected to the control unit and the amplifying unit for temperature control.

[0005] Further, the amplification unit is composed of a plurality of power amplification basic units, and the power amplification basic unit includes a signal input terminal, an input matching network, a gate network, a stabilization network, a power tube, a drain network, an output matching network, and a signal output terminal;

[0006] The signal input terminal is connected to the input matching network, and the output terminal of the input matching network is respectively connected to the input terminal of the gate network and the input terminal of the stabilization network; the output terminal of the stabilization network is connected to the input terminal of the power tube, and the output terminal of the power tube is respectively connected to the input terminal of the drain network and the input terminal of the output matching network; the output terminal of the output matching network is connected to the signal output terminal.

[0007] Furthermore, the input matching network and the output matching network both use a transmission line transformer; the transmission line transformer comprises: a magnetic ring and a transmission line; the transmission line is wound around the magnetic ring; the transmission line is a mutually insulated twisted pair or coaxial line.

[0008] Furthermore, the stabilizing network includes an attenuator or a limiter, the attenuator is used to reduce input power, and the limiter is used to reduce a frequency point with high gain.

[0009] Further, the gate network includes: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, transistor Q1, diode D1, and voltage-stabilizing diode D2; the capacitor C1, capacitor C2, and capacitor C3 are connected in parallel and then connected in series to the E end of the transistor Q1, and the capacitor C4, capacitor C5, resistor R2, and resistor R3 are connected in parallel and then connected in series to the C end of the transistor Q1; the resistor R4, voltage-stabilizing diode D2, and resistor R6 are connected in series and then connected to the B end of the transistor Q1; the resistor R1, diode D1, and resistor R5 are connected in series and then connected in parallel to the E end and the B end of the transistor Q1; the capacitor C6 and capacitor C7 are connected in parallel and then connected in series to the resistor R1.

[0010] Furthermore, it also includes a temperature detector, which is connected to the power tube, and the temperature detection range of the temperature detector is -45°C to 120°C.

[0011] Furthermore, the input matching network termination lead-in impedance and the output matching network termination lead-out impedance are both 50Ω.

[0012] The utility model provides a multi-octave broadband power amplifier, which has the following beneficial effects:

[0013] The utility model solves the problems of single radio function and insufficient frequency band coverage in the prior art, and realizes the multi-function and multi-octave coverage of the radio. At the same time, it has the advantages of small size and easy operation, which greatly reduces the production cost and saves time cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the utility model 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 of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0015] Figure 1 A schematic diagram of the structure of a broadband power amplifier provided by the utility model;

[0016] Figure 2 A structural diagram of a power amplification basic unit provided by the utility model;

[0017] Figure 3The power tube data parameters of the embodiment provided by the utility model;

[0018] Figure 4 A schematic diagram of the grid network structure provided by the utility model;

[0019] Figure 5 Gain link allocation for the amplifier unit provided by the utility model;

[0020] In the figure, 1, control unit; 2, amplification unit; 3, filtering unit; 4, detection unit; 5, heat dissipation unit; 2-1, signal input terminal; 2-2, input matching network; 2-3, gate network; 2-4, stabilization network; 2-5, power tube; 2-6, drain network; 2-7, output matching network; 2-8, signal output terminal. DETAILED DESCRIPTION

[0021] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0022] The following is a detailed description of the implementation method of the present invention in conjunction with the accompanying drawings. Only some embodiments are described, not all embodiments. For the purpose of clarity, representations and descriptions that are not related to the present invention are omitted in the drawings and descriptions.

[0023] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the utility model, the technical solution of the utility model is now described in detail below. Obviously, the implementation cases described are part of the embodiments of the utility model, not all of the embodiments, and cannot be understood as limiting the scope of implementation of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.

[0024] like Figure 1 As shown, the utility model provides a multi-octave broadband power amplifier, comprising an amplifying unit 2, a control unit 1, a filtering unit 3, a detection unit 4, and a heat dissipation unit 5.

[0025] After receiving the external control signal, the control unit 1 transmits the control instruction to the amplifying unit 2; the amplifying unit 2 receives the RF signal and the control instruction of the control unit 1, performs power amplification, and then transmits it to the filtering unit 3; the filtering unit 3 filters out the harmonics in the amplified RF signal and transmits it to the detection unit 4 for coupling and detection, and then outputs it to the control unit 1 and the outside respectively; the two ends of the heat dissipation unit 5 are respectively connected to the control unit 1 and the amplifying unit 2 for temperature control.

[0026] The control unit 1 is a logic control unit composed of a diode, a triode, a field effect transistor, a resistor and a capacitor; the filter unit 3 is a switch filter unit composed of a radio frequency diode, a power inductor, a high-Q capacitor and a logic circuit; the detection unit 4 is a detection unit 4 composed of a coupler, a detector and a power supply filter; the heat dissipation unit 5 is composed of a conductive copper pad and an integrated aluminum heat sink, wherein the conductive copper pad is used to conduct heat instantly, and the integrated aluminum heat sink is used to reduce thermal resistance.

[0027] The amplifier unit is composed of multiple power amplifier basic units, such as Figure 2 As shown, the power amplification basic unit includes a signal input terminal 2-1, an input matching network 2-2, a gate network 2-3, a stabilizing network 2-4, a power tube 2-5, a drain network 2-6, an output matching network 2-7, and a signal output terminal 2-8.

[0028] The signal input terminal 2-1 is connected to the input matching network 2-2, and the output terminal of the input matching network 2-2 is respectively connected to the input terminal of the gate network 2-3 and the input terminal of the stabilization network 2-4; the output terminal of the stabilization network 2-4 is connected to the input terminal of the power tube 2-5, and the output terminal of the power tube 2-5 is respectively connected to the input terminal of the drain network 2-6 and the input terminal of the output matching network 2-7; the output terminal of the output matching network 2-7 is connected to the signal output terminal 2-8.

[0029] The power tube 2-5 uses a gallium nitride (GaN) power tube 2-5, and the matching method uses a transmission line transformer.

[0030] GaN power tubes 2-5 are active transistors and are the core devices of the amplification unit. Their advantages are high gain, wide bandwidth, easy expansion, and high efficiency; their disadvantages are low impedance characteristics and poor reliability.

[0031] The reliability of the power tube 2-5 is improved by the gate network and the drain network. The gate network can improve the gate voltage Vg and provide an ideal static working point for the power tube 2-5; the drain network filters and turns on / off the drain voltage Vd. The gate network and the drain network provide stable Vg and Vd for the power tube 2-5 to prevent it from oscillating during operation. The gate network provides gate protection and temperature protection for the power tube 2-5. The gate voltage of the GaN power tube 2-5 is negative, and the power supply has a sequence. The gate protection circuit provides a normal power supply sequence for the power tube 2-5. If the external power supply sequence is abnormal, the gate and drain power supply of the power tube 2-5 will be turned off. The power tube 2-5 is a heat source. In addition to taking necessary heat dissipation measures, temperature protection must also be designed. When the temperature is abnormal (greater than 85 degrees Celsius), the power supply of the power tube 2-5 is turned off. The gate network thus improves the reliability of the power tube 2-5.

[0032] The input and output matching networks can improve the impedance characteristics of power tubes 2-5. It is a key measure for frequency expansion. The ideal working impedance of the RF network is 50Ω, which is difficult to achieve in engineering implementation. It can only be achieved as much as possible through design matching. The matching method uses a transmission line transformer. The transmission line transformer has a simple structure and is realized by winding a transmission line (mutually insulated twisted pair, coaxial line, etc.) around a magnetic ring. The frequency range covered by the transmission line is from KHz to MHz, and the length is generally determined by the center frequency of the working frequency band, which is generally a quarter wavelength. The magnetic permeability of the magnetic ring determines the frequency of the transformer impedance transformation. The higher the magnetic permeability, the lower the frequency, and the lower the magnetic permeability, the higher the frequency.

[0033] The input matching network 2-2 and the output matching network 2-7 both use a transmission line transformer; the transmission line transformer includes: a magnetic ring and a transmission line; the transmission line is wound around the magnetic ring; the transmission line is a mutually insulated twisted pair or coaxial line.

[0034] The stabilization network 2-4 includes an attenuator or a limiter. The attenuator is used to reduce the input power, and the limiter is used to reduce the frequency point with high gain. The stabilization network 2-4 takes measures to prevent power oscillation and other problems. For example, if the input is too high, an attenuator can be added to reduce the input power; if the gain is uneven, a limiter can be added to reduce the frequency point with high gain.

[0035] The grid network includes, for example Figure 4 As shown: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, capacitor C7, transistor Q1, diode D1, and voltage-stabilizing diode D2; the capacitor C1, capacitor C2, and capacitor C3 are connected in parallel and then connected in series to the E end of the transistor Q1, the capacitor C4, capacitor C5, resistor R2, and resistor R3 are connected in parallel and then connected in series to the C end of the transistor Q1; the resistor R4, voltage-stabilizing diode D2, and resistor R6 are connected in series and then connected to the B end of the transistor Q1; the resistor R1, diode D1, and resistor R5 are connected in series and then connected in parallel to the E end and the B end of the transistor Q1; the capacitor C6 and capacitor C7 are connected in parallel and then connected in series to the resistor R1.

[0036] It also includes a temperature detector, which is connected to the power tube 2-5, and the temperature detection range of the temperature detector is -45°C to 120°C. The input matching network 2-2 terminal lead-in impedance and the output matching network 2-7 terminal lead-out impedance are both 50Ω.

[0037] Embodiment: The frequency expansion method is adopted to make it work in a multi-octave range. Its basic unit is power tube amplification, including power tube, input / output matching network, stabilization network, gate network, drain network, input / output DC isolation network. The broadband power amplifier is composed of several basic units according to the needs. The power tube is an active transistor and is the core device of the power amplifier. Its performance index directly determines the performance of the power amplifier. The matching network includes input and output matching networks. It is a key measure for frequency expansion. The optimal impedance matching of the RF network is 50Ω, and the matching network uses impedance transformation to make the input and output ends of the power tube 50Ω. The gate network provides the gate bias voltage of the power tube and adjusts the static operating point of the power tube. The drain network provides a stable drain voltage of the power tube to avoid its working oscillation. The DC isolation network usually selects capacitors within the working frequency band, mainly to prevent DC signals from entering other networks and causing damage to the device. The stabilization network is a measure taken to prevent power oscillation and other problems. If the power amplifier is composed of multiple stages of amplification circuits, the structure of each stage is basically the same, the difference is the output power, and the impedance matching between stages needs to be considered.

[0038] Octave is a representation of ultra-wideband. Octave can be expressed as N: 2 N =f2 / f1, f1 is the working start frequency, f2 is the working cut-off frequency, and the value of N is the multiple of frequency.

[0039] Taking a broadband power amplifier with a working frequency band of 100~1000MHz and an output power of 100W as an example, the realization of multiple frequency expansion is analyzed and explained.

[0040] The power amplifier adopts modular design and traditional unit mode, and is composed of RF amplification unit, control unit, filter unit, detection unit, heat dissipation unit, etc. Highly integrated and highly reliable devices are selected, and low-power design is adopted to reduce power consumption. The RF amplification unit adopts multi-stage power amplification. The control unit provides state control, communication with the outside, and DC-DC conversion. The filter unit includes a filter group and a switch component. The filter group includes multiple filters of different frequencies to filter out harmonics within the working frequency band. The switch component selects different filters according to the working frequency. The detection unit couples and detects the RF output signal. The heat dissipation unit is mainly composed of a radiator and a fan to dissipate heat for the power amplifier. The power tube is the main heat source, and the heat generated by it needs to be dissipated and conducted away.

[0041] The RF amplifier unit uses a 4-stage amplifier tube for amplification, such as Figure 5As shown. 4-stage power gain distribution: π-type network -5dB, first stage gain 14dB, second stage gain 18dB, third stage gain 10dB, fourth stage gain 15dB, total gain is 52dB. Considering the wide frequency bandwidth, in order to take into account the power output of the entire frequency band, when selecting the amplifier, full consideration should be given to leaving margin.

[0042] The power tube is the core component of the RF amplifier unit, and the selection of power tubes suitable for working in this frequency band is the key. A4, as the final stage of the RF amplifier unit, is the core of the entire broadband power amplifier design. In the 100~1000MHz frequency band, the LDMOS transistors commonly used on the market have a maximum frequency bandwidth of 600MHz, and the operating frequency bandwidth is basically only 200MHz. The coverage frequency expansion is poor, and the frequency expansion of LDMOS transistors is based on the sacrifice of the gain, output power, efficiency and other parameters of the power tube, which is often not worth the loss; the efficiency is poor, and under the condition of saturated power output, the efficiency can only be around 30%. In recent years, with the improvement of the process level of GaN power tubes, their stability, frequency expansion and efficiency have been improved. It has been widely used in radio stations and communications. The domestically produced GaN power tubes selected have a frequency bandwidth coverage of up to 2000Mhz, an output power of 600W, a power supply of DC50V, and an efficiency of 66%. Figure 3 shown.

[0043] Due to the characteristics of GaN power tubes, their reliability is poor compared to LDMOS transistors. Unspecified factors may cause damage to the power tube during use. To further improve the reliability of the power amplifier, a protection function needs to be designed. When the power amplifier is in an abnormal working state, the protection function starts to work, automatically shuts down the working state of the power amplifier, or even turns off the power supply, thereby protecting the power tube from damage. The protection function is generally divided into temperature protection, standing wave protection, gate protection, etc.

[0044] Temperature protection: The power tube is the heat source of the power amplifier. The temperature can reach hundreds of degrees Celsius during operation. While taking necessary heat dissipation measures, the operating temperature must be monitored. When the temperature rises beyond the limit that the device can withstand, it may cause the device performance to degrade or even be damaged. The temperature detector is generally placed near the high-heating power device. The voltage value output by the temperature detector corresponds to a certain temperature, such as (30°=0.8V). The temperature detection voltage is input into the protection circuit or MCU and compared with the preset temperature threshold value. When the device temperature reaches a certain value, the protection function starts to work, and the device will work or even stop working.

[0045] Standing wave protection: When the load impedance is inconsistent with the output impedance of the device, the reflected wave and the incident wave are superimposed on the feeder to form a standing wave. The ratio of the maximum and minimum values ​​of the adjacent voltages is the voltage standing wave ratio. If the voltage standing wave ratio is too large, the power obtained by the load will be reduced, and the working efficiency of the power amplifier equipment will be reduced. In addition, the reflected power will return to the power amplifier part of the transmitter, which is easy to burn out the power amplifier tube and affect the normal operation of the system. Monitoring standing waves requires the coupler to sample the forward and reverse RF signals.

[0046] The sampling signal is detected and two detection voltages are output. The protection circuit determines the two voltages and when they reach a certain value, the standing wave protection function is turned on and the power amplifier stops working.

[0047] Gate protection: Since the gate voltage of the GaN power tube is negative, the gate voltage must be turned on in advance. The power-on sequence of the GaN power tube is gate first, then drain; the power-off sequence is drain first, then gate. Otherwise, the power tube will be damaged. This feature is different from LDMOS transistors.

[0048] The gate voltage is the key to the GaN power tube. The presence or absence of gate voltage is determined in the drain circuit. When the gate voltage exists, the drain circuit is turned on, the drain voltage is output, and the power tube works; otherwise, the drain circuit is turned off. The gate circuit changes the working state of the power tube, generally switching between the static working point voltage and the -5V voltage. When the power amplifier switches the working state, the gate circuit changes the working state of the power tube accordingly. The gate circuit and the drain circuit jointly provide a power-on sequence for the GaN power tube. When an abnormality occurs, the power supply to the power tube is stopped, thereby protecting the power tube.

[0049] The gate network includes: a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a capacitor C7, a transistor Q1, a diode D1, and a voltage-stabilizing diode D2; the capacitor C1, the capacitor C2, and the capacitor C3 are connected in parallel and then connected in series to the E end of the transistor Q1, the capacitor C4, the capacitor C5, the resistor R2, and the resistor R3 are connected in parallel and then connected in series to the C end of the transistor Q1; the resistor R4, the voltage-stabilizing diode D2, and the resistor R6 are connected in series and then connected to the B end of the transistor Q1; the resistor R1, the diode D1, and the resistor R5 are connected in series and then connected in parallel to the E end and the B end of the transistor Q1; the capacitor C6 and the capacitor C7 are connected in parallel and then connected in series to the resistor R1.

[0050] Transmission line transformer: It consists of a ring-shaped magnetic core and a transmission line. The magnetic core is made of high permeability, low-loss ferrite material. Its diameter can be large or small (depending on the power), ranging from a few millimeters to tens of millimeters. The transmission line is wound around the magnetic core to form a transmission line transformer, the highest frequency of which can reach hundreds of megahertz or even thousands of megahertz.

[0051] The transmission line transformer is placed at the input and output ends of the power tube. The number of transmission line transformers used depends on the type of power tube. When the power tube is a single tube, one is generally used for input and output; when the power tube is a pair of tubes, two are generally used for input and output. The power tube is a pair of tubes, and two identical transmission line transformers are placed at the input and output ends. The transmission line selects a coaxial line with an impedance of 25Ω and a length of 58mm, and a double-hole magnetic ring with a magnetic permeability of 15. During installation, the two transformers are opposite to each other. The transmission line length, the magnetic permeability of the magnetic ring, and the position of the transmission line transformer installation relative to the tube pin have a particularly obvious effect on the impedance transformation. The three are flexibly adjusted according to the specific parameters required by the amplification unit during engineering implementation.

[0052] The stabilizing network is a π-type network with an attenuation value of 5dB to improve the standing wave between cascades. The attenuation value can be adjusted according to the amplifier gain requirements and is designed and simulated under 50Ω impedance.

[0053] The selection of GaN power tubes and the design of suitable transmission line transformers enable the power amplifier to operate at multiple octaves, and the efficiency, linearity and other indicators of the power amplifier meet the use requirements. Impedance transformation at multiple octaves may reduce the reliability of the power tube, and the protection circuit can greatly improve the reliability of the power tube.

[0054] The above is only a preferred embodiment of the utility model. It should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. A multi-octave broadband power amplifier, characterized in that: It comprises an amplification unit (2), a control unit (1), a filtering unit (3), a detection unit (4), and a heat dissipation unit (5); The control unit (1) receives an external control signal and transmits the control instruction to the amplifying unit (2); the amplifying unit (2) receives the radio frequency signal and the control instruction of the control unit (1), performs power amplification, and transmits the signal to the filtering unit (3); the filtering unit (3) filters out the harmonics in the amplified radio frequency signal and transmits the signal to the detection unit (4) for coupling and detection, and then outputs the signal to the control unit (1) and the outside respectively; the two ends of the heat dissipation unit (5) are respectively connected to the control unit (1) and the amplifying unit (2) for temperature control.

2. The multi-octave broadband power amplifier according to claim 1, characterized in that: The amplification unit (2) is composed of a plurality of power amplification basic units, wherein the power amplification basic units include a signal input terminal (2-1), an input matching network (2-2), a gate network (2-3), a stabilization network (2-4), a power tube (2-5), a drain network (2-6), an output matching network (2-7), and a signal output terminal (2-8); The signal input terminal (2-1) is connected to the input matching network (2-2); the output terminal of the input matching network (2-2) is respectively connected to the input terminal of the gate network (2-3) and the input terminal of the stabilization network (2-4); the output terminal of the stabilization network (2-4) is connected to the input terminal of the power tube (2-5); the output terminal of the power tube (2-5) is respectively connected to the input terminal of the drain network (2-6) and the input terminal of the output matching network (2-7); and the output terminal of the output matching network (2-7) is connected to the signal output terminal (2-8).

3. The multi-octave broadband power amplifier according to claim 2, characterized in that: The input matching network (2-2) and the output matching network (2-7) both use a transmission line transformer; the transmission line transformer comprises: a magnetic ring and a transmission line; the transmission line is wound around the magnetic ring; the transmission line is a mutually insulated twisted pair or coaxial line.

4. The multi-octave broadband power amplifier according to claim 2, characterized in that: The stabilizing network (2-4) comprises an attenuator or a limiter, wherein the attenuator is used to reduce input power, and the limiter is used to reduce a frequency point with high gain.

5. The multi-octave broadband power amplifier according to claim 2, characterized in that: The gate network (2-3) comprises: a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a capacitor C7, a transistor Q1, a diode D1, and a voltage-stabilizing diode D2; the capacitor C1, the capacitor C2, and the capacitor C3 are connected in parallel and then connected in series to the E end of the transistor Q1; the capacitor C4, the capacitor C5, the resistor R2, and the resistor R3 are connected in parallel and then connected in series to the C end of the transistor Q1; the resistor R4, the voltage-stabilizing diode D2, and the resistor R6 are connected in series and then connected to the B end of the transistor Q1; the resistor R1, the diode D1, and the resistor R5 are connected in series and then connected in parallel to the E end and the B end of the transistor Q1; the capacitor C6 and the capacitor C7 are connected in parallel and then connected in series to the resistor R1.

6. The multi-octave broadband power amplifier according to claim 2, characterized in that: It also includes a temperature detector, which is connected to the power tube (2-5), and the temperature detection range of the temperature detector is -45°C to 120°C.

7. The multi-octave broadband power amplifier according to claim 2, characterized in that: The input matching network (2-2) terminal lead-in impedance and the output matching network (2-7) terminal lead-out impedance are both 50Ω.

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