Broadband low-noise amplifier

Abstract

The invention discloses a broadband low-noise amplifier, and belongs to the technical field of monolithic microwave integrated circuits. Comprising a current multiplexing structure low-noise amplifier and a balanced low-noise amplifier which are cascaded, the current multiplexing low-noise amplifier comprises a first-stage amplification circuit and a second-stage amplification circuit which are cascaded in sequence, the balanced low noise amplifier comprises two folding Lange couplers and two amplification branches, the two amplification branches are of the same two-stage amplification circuit structure and comprise a third-stage amplification circuit and a fourth-stage amplification circuit which are cascaded and have the same structure; pHEMT (Pseudomorphic High Electron Mobility Transistor) tubes are adopted as amplifying devices in each amplifying circuit, and the broadband low-noise amplifier is integrated on a monolithic gallium arsenide. By combining the current multiplexing technology, the Lange coupler folding technology, the negative feedback technology and the balanced structure, the noise coefficient is effectively reduced, the power consumption is reduced, the layout area is reduced, and the performance of a traditional balanced low-noise amplifier is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of monolithic microwave integrated circuits, and in particular to current multiplexing technology, Lange coupler folding technology, negative feedback technology and a broadband low-noise amplifier with a balanced structure. Background Art

[0002] With the rapid development of modern wireless communication technology, the requirements for noise, bandwidth and miniaturization of RF receivers are becoming higher and higher. As one of the most critical components of the RF receiving front end, the low noise amplifier (LNA) can reduce noise crosstalk while providing a certain gain to the RF signal received by the antenna. Its performance directly affects the overall performance of the broadband receiver.

[0003] The traditional balanced low-noise amplifier is a common broadband low-noise amplifier. This structure provides a good port voltage standing wave ratio, but the RF signal passes through the Lange coupler before entering the amplifier circuit. The overall noise and power consumption are difficult to reduce, and the chip area is large, resulting in high manufacturing costs. Therefore, structural optimization is required to reduce the noise factor, power consumption and chip area.

[0004] In summary, the traditional balanced low noise amplifier structure has problems such as high noise figure, high power consumption, and large layout area, which limits its application in modern wireless communication systems. Therefore, it is necessary to develop a new type of broadband low noise amplifier that can achieve low noise, low power consumption and miniaturization while ensuring broadband performance. Summary of the invention

[0005] In view of this, the present invention provides a broadband low-noise amplifier, which can at least partially solve the problems of high noise coefficient, high power consumption, large layout area, etc. in the low-noise amplifier structure in the above-mentioned prior art. The present invention combines current multiplexing technology, Lange coupler folding technology, negative feedback technology and balanced structure to effectively reduce noise coefficient, power consumption, and layout area, thereby improving the performance of traditional balanced low-noise amplifiers.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A broadband low-noise amplifier provided by an embodiment of the present invention comprises: a cascaded current multiplexing structure low-noise amplifier and a balanced low-noise amplifier;

[0008] Wherein, the current multiplexing low noise amplifier comprises: a first-stage amplifier circuit and a second-stage amplifier circuit which are cascaded in sequence;

[0009] The balanced low-noise amplifier comprises: a folded Lange coupler 1, a folded Lange coupler 2, a first amplifying branch, and a second amplifying branch; one end of the first amplifying branch is connected to the coupling output end of the folded Lange coupler 1, and the other end is connected to the coupling input end of the folded Lange coupler 2; one end of the second amplifying branch is connected to the through output end of the folded Lange coupler 1, and the other end is connected to the through input end of the folded Lange coupler 2;

[0010] The first amplifying branch and the second amplifying branch are both of the same two-stage amplifying circuit structure, including a cascaded third-stage amplifying circuit, a fourth-stage amplifying circuit, a negative feedback module 1 adapted to the third-stage amplifying circuit, and a negative feedback module 2 adapted to the fourth-stage amplifying circuit;

[0011] The third-stage amplifier circuit and the fourth-stage amplifier circuit have the same amplifier circuit structure;

[0012] The amplifier devices in each amplifier circuit all adopt PHEMT tubes, and the broadband low-noise amplifier is integrated on a single-chip gallium arsenide.

[0013] It can be seen from the above technical solution that compared with the prior art, the present invention has the following advantages:

[0014] 1. Low noise coefficient: In this solution, the RF signal directly enters the first-stage amplifier circuit, rather than passing through the Lange coupler before entering the first-stage amplifier circuit, thus avoiding the high noise coefficient caused by the loss of the Lange coupler itself.

[0015] 2. Low overall power consumption: The two-stage amplifier circuits in the current multiplexing structure low-noise amplifier share current, reducing the overall power consumption.

[0016] 3. Miniaturization: The current multiplexing structure low-noise amplifier circuit is simple and easy to layout, reducing the horizontal size of the layout; the folded Lange coupler reduces the vertical size of the layout, making the overall layout more compact.

[0017] 4. High stability: The filter capacitors in the first and second feeding modules are connected in series with resistors to the ground and the negative feedback modules in the third and fourth amplifier circuits improve the stability of the overall circuit.

[0018] 5. Good broadband characteristics: The matching module in the current multiplexing structure low noise amplifier adopts broadband matching to achieve broadband characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention 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 embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the framework of a broadband low noise amplifier provided by the present invention;

[0021] Figure 2 A schematic diagram of the structure of a current multiplexing structure low noise amplifier provided by the present invention;

[0022] Figure 3 A schematic diagram of the structure of the first amplifying branch of the balanced low noise amplifier provided by the present invention;

[0023] Figure 4 A schematic diagram of the structure of the folded Lange coupler provided by the present invention;

[0024] Figure 5 A circuit schematic diagram of a broadband low noise amplifier in a specific implementation manner provided by the present invention;

[0025] Figure 6 A diagram showing the return loss simulation results of a broadband low noise amplifier in a specific implementation manner provided by the present invention;

[0026] Figure 7 A noise figure simulation result diagram of a broadband low noise amplifier in a specific implementation manner provided by the present invention;

[0027] Figure 8 A diagram showing the output gain simulation results of a broadband low noise amplifier in a specific embodiment of the present invention;

[0028] Fig. 9 This is a simulation result diagram of the output power 1dB compression point of the broadband low noise amplifier in the specific implementation manner provided by the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0030] The present invention combines current multiplexing technology, Lange coupler folding technology, negative feedback technology and balanced structure to effectively reduce noise coefficient, power consumption, and layout area, thereby improving the performance of a traditional balanced low-noise amplifier.

[0031] In the related art, the current multiplexing structure can effectively reduce the power consumption of the circuit because the transistors share the current. At the same time, the output can superimpose the gains of various levels, making the gain improvement efficiency of the low-noise amplifier higher without adding additional current, and additionally reducing the need for independent bias circuits, so that the chip area and the complexity of the peripheral circuits are reduced, but the realization of broadband characteristics requires a complex input and output matching structure. The present invention is equipped with multiple matching modules.

[0032] The size of the Lange coupler is directly related to its operating frequency band. The coupling line width and coupling spacing are very small compared to the coupling line length, which makes the aspect ratio of the Lange coupler very large, resulting in a large area waste when laying out the chip layout. Therefore, the present invention can ensure performance while facilitating layout by folding the Lange coupler, thereby realizing the miniaturization of the low-noise amplifier.

[0033] In addition, the frequency response of the amplifier is mainly limited by the parasitic parameters of the transistor, among which the parasitic capacitance between the gate and the source determines the operating bandwidth, and the parasitic capacitance between the gate and the drain determines the upper cutoff frequency of the amplifier. The present invention adds a feedback loop between the gate and the drain to expand the operating bandwidth of the amplifier.

[0034] Combined with the above structure, the present invention can achieve lower noise, lower power consumption and smaller layout area of ​​the low noise amplifier.

[0035] like Figure 1 As shown, an embodiment of the present invention discloses a broadband low noise amplifier, including: a cascaded current multiplexing structure low noise amplifier and a balanced low noise amplifier; the current multiplexing low noise amplifier includes a first-stage amplifier circuit and a second-stage amplifier circuit cascaded in sequence; the balanced low noise amplifier includes a folded Lange coupler 1, a folded Lange coupler 2, a first amplifier branch connected to the coupled output end of the folded Lange coupler 1 and the coupled input end of the folded Lange coupler 2, and a second amplifier branch connected to the through output end of the folded Lange coupler 1 and the through input end of the folded Lange coupler 2; in the broadband low noise amplifier, the amplifier devices all use PHEMT tubes, and the entire amplifier circuit is integrated on a single chip of gallium arsenide.

[0036] Among them, the above-mentioned current multiplexing structure low noise amplifier, such as Figure 2 As shown, the first-stage amplifier circuit includes a PHEMT tube M1, and the second-stage amplifier circuit includes a PHEMT tube M2; the input radio frequency signal RF inIt enters the gate of PHEMT tube M1 through matching module one, is amplified and output from the drain, enters the gate of PHEMT tube M2 through interstage matching module two, is output from the drain of PHEMT tube M2, and enters the input end of folded Lange coupler one through matching module three.

[0037] The self-bias module 1 is connected to the source of the PHEMT tube M1 to provide a source bias voltage for the PHEMT tube; the current multiplexing module is connected between the drain of the PHEMT tube M1 and the source of the PHEMT tube M2 to provide a DC path for the PHEMT tubes M1 and M2; the feeding module 1 provides a gate bias voltage for the PHEMT tube M2, and the feeding module 2 provides a drain bias voltage for the PHEMT tube M2; the DC path is DC power supply → feeding module 2 → PHEMT tube M2 → current multiplexing module → PHEMT tube M1 → self-bias module 1.

[0038] In the balanced low noise amplifier, the first amplifying branch and the second amplifying branch are both the same two-stage amplifying circuit structure, including a cascaded third-stage amplifying circuit and a fourth-stage amplifying circuit, and the third-stage amplifying circuit and the fourth-stage amplifying circuit are the same amplifying circuit structure.

[0039] For example, the first amplification branch Figure 3 As shown, the third-stage amplifier circuit includes a PHEMT tube M3, and the fourth-stage amplifier circuit includes a PHEMT tube M4; the radio frequency signal RF from the first coupling output end of the folded Lange coupler in It enters the gate of the PHEMT tube M3 through the matching module four, is amplified and output from the drain, enters the gate of the PHEMT tube M4 through the matching module five, is output from the drain of the PHEMT tube M4, and enters the coupling input end of the folded Lange coupler two through the matching module six; the self-bias module two is connected to the source of the PHEMT tube M3, and the self-bias module three is connected to the source of the PHEMT tube M4 to provide a source bias voltage for the PHEMT tube; the negative feedback module one is connected between the drain and the gate of the PHEMT tube M3, and the negative feedback module two is connected between the drain and the gate of the PHEMT tube M4. The negative feedback module can effectively expand the bandwidth, adjust the standing wave and stability, and improve the gain flatness; the feeding module three provides a drain bias voltage for the PHEMT tube M3, and the feeding module four provides a drain bias voltage for the PHEMT tube M4.

[0040] The folded Lange coupler 1 and the folded Lange coupler 2 are as follows: Figure 4As shown in the figure, the parameters of the two are the same, such as line width, line length and line spacing. The structure includes input port, through port, coupled port and isolated port. In actual use, the signal is input from the input port, output from the through port and coupled port, and the isolated port is cascaded with a 50Ω resistor to the ground. The folded Lange coupler adopts a bent structure to reduce the vertical size, facilitate layout, and reduce the overall layout area.

[0041] The present invention adopts a current reuse structure, and the RF signal directly enters the amplifier circuit, avoiding the loss of the Lange coupler and reducing the noise coefficient. Moreover, the current reuse structure reduces the circuit power consumption and has a higher output gain. In addition, the current reuse structure simplifies the circuit layout, and the folded Lange coupler reduces the chip area to achieve miniaturization. Adding a feed module filter capacitor series resistor and a negative feedback module improves the circuit stability. Finally, the current reuse structure adopts broadband matching to achieve good broadband characteristics.

[0042] Combine the following Figure 5 Circuit schematic diagram, detailing the above modules of the present invention:

[0043] like Figure 5 As shown, it is a circuit schematic diagram of a broadband low noise amplifier, including a cascaded current multiplexing structure low noise amplifier and a balanced low noise amplifier. The current multiplexing structure low noise amplifier includes a first-stage amplifier circuit and a second-stage amplifier circuit cascaded in sequence. The balanced low noise amplifier includes a folded Lange coupler 1, a folded Lange coupler 2, a first amplifier branch connected to the coupled output end of the folded Lange coupler 1 and the coupled input end of the folded Lange coupler 2, and a second amplifier branch connected to the through output end of the folded Lange coupler 1 and the through input end of the folded Lange coupler 2. The amplifier devices in the broadband low noise amplifier all use PHEMT tubes, and the entire amplifier circuit is integrated on a single-chip gallium arsenide.

[0044] 1. Current multiplexing structure low noise amplifier:

[0045] In the current multiplexing structure low noise amplifier, the first stage amplifying circuit includes a PHEMT tube M1, and the second stage amplifying circuit includes a PHEMT tube M2.

[0046] Specifically, the cascaded capacitor C1 and the T-type microstrip transmission line T1 constitute the input matching of the PHEMT tube M1, which is used to receive the RF input signal RF in , and the RF input signal RF in Broadband impedance matching is performed to obtain a broadband matching signal; capacitor C1 is used to isolate the DC signal; the vertical lower end of the T-type microstrip line T1 is grounded to provide a zero bias voltage for the gate of the PHEMT tube M1.

[0047] The parallel resistor R1 and capacitor C2 form a self-bias, which is connected to the source level of the PHEMT tube M1; the resistor R1 is used for voltage division to provide a source bias voltage for the PHEMT tube M1; the capacitor C2 is used for transmitting the radio frequency signal to the ground.

[0048] Microstrip line TL1, capacitor C3 and the vertical lower end and vertical end of the T-type microstrip line T2 constitute the inter-stage matching of PHEMT tube M1 and PHEMT tube M2; capacitor C3 is used to isolate the gate bias voltage of PHEMT tube M2 and the drain voltage of PHEMT tube M1, ensuring the difference between the two.

[0049] The vertical lower end, vertical end and capacitor C7 of the T-type microstrip line T3 constitute the broadband output matching of the PHEMT tube M2. The capacitor C7 is also used to isolate the drain bias voltage of the PHEMT tube M2 and the RF signal input port of the folded Lange coupler Lange1.

[0050] The microstrip lines (TL1, TL2, TL3), the resistor R2 and the capacitor C4 form a DC path of the PHEMT tube M1 and the PHEMT tube M2, provide a suitable DC bias for the PHEMT tube, and filter out the radio frequency signal in the DC path.

[0051] Resistors (R3, R4, R5), capacitor C5 and the vertical upper end and vertical end of the T-type microstrip line T2 constitute the gate bias circuit of the PHEMT tube M2, which is used to provide a gate bias voltage; resistors (R3, R4) are used to divide the DC voltage to provide a suitable output voltage value; capacitor C5 and resistor R5 are used to filter out high-frequency noise and ensure voltage stability; the vertical upper end of the T-type microstrip line T2 is used for choking inductance to hinder the transmission of radio frequency signals.

[0052] Resistors (R6, R7), capacitor C6 and the vertical upper end and vertical lower end of the T-type microstrip line T3 constitute the drain bias circuit of the PHEMT tube M2, which is used to provide a drain bias voltage; resistor R6 and capacitor C6 are used to filter out high-frequency noise and ensure voltage stability; resistors (R1, R2, R7) are used together for voltage division in the DC path; the vertical upper end of the T-type microstrip line T3 is used for choking inductance to hinder the transmission of radio frequency signals.

[0053] 2. Balanced low noise amplifier:

[0054] The balanced low-noise amplifier comprises a folded Lange coupler 1, a folded Lange coupler 2, a first amplifying branch connected to a coupled output end of the folded Lange coupler 1 and a coupled input end of the folded Lange coupler 2, and a second amplifying branch connected to a through output end of the folded Lange coupler 1 and a through input end of the folded Lange coupler 2.

[0055] The folded Lange coupler 1 is Lange1, and the folded Lange coupler 2 is Lange2. The two have the same size, parameters and performance, and both use the folded line length method for miniaturization of the layout; the resistor R8 and the resistor R17 are respectively connected to the isolation ends of Lange1 and Lange2 and connected to the ground.

[0056] 2.1. The first amplifying branch is exactly the same as the second amplifying branch. The first amplifying branch is taken as an example for detailed description below:

[0057] The first amplifying branch includes a cascaded third-stage amplifying circuit and a fourth-stage amplifying circuit. The third-stage amplifying circuit includes a PHEMT tube M3, and the fourth-stage amplifying circuit includes a PHEMT tube M4.

[0058] Specifically, the vertical lower end and the vertical end of the T-type microstrip line T4 constitute the input matching of the PHEMT tube M3; the vertical lower end of the T-type microstrip line T4 is grounded to provide a gate zero bias voltage for the PHEMT tube M3.

[0059] The parallel resistor R10 and capacitor C9 form a self-bias, which is connected to the source level of the PHEMT tube M3; the resistor R10 is used for voltage division to provide a source bias voltage for the PHEMT tube M3; the capacitor C9 is used for transmitting the radio frequency signal to the ground.

[0060] Similarly: the parallel resistor R12 and capacitor C13 form a self-bias, which is connected to the source level of the PHEMT tube M4; the resistor R12 is used for voltage division to provide a source bias voltage for the PHEMT tube M4; the capacitor C13 is used to transmit the radio frequency signal to the ground.

[0061] The vertical upper end of the cascaded T-type microstrip line T4, resistor R9 and capacitor C8 form a negative feedback loop, which is used to improve high-frequency flatness, expand bandwidth and enhance amplifier stability; the vertical upper end of the T-type microstrip line T4 can reduce the feedback amount of the feedback loop in the high-frequency band, compensate for the decrease in the high-frequency gain of the tube core, and improve the gain flatness; resistor R9 can adjust the low-frequency gain of the circuit, and when the resistance value decreases, the feedback amount increases, which will cause the low-frequency gain to decrease; capacitor C8 is used to isolate the gate bias voltage and drain bias voltage of the PHEMT tube M3.

[0062] like Figure 5 As shown, the negative feedback module 2 is composed of the vertical upper end of the cascaded T-type microstrip line T6, the resistor R11 and the capacitor C12 to form a negative feedback loop.

[0063] The vertical upper end of the T-shaped microstrip line T5 and the capacitor C10 form a drain bias circuit of the PHEMT tube M3 to provide a drain bias voltage.

[0064] like Figure 5As shown, the feed module 4 is composed of the vertical upper end of the T-type microstrip line T7 and the capacitor C14 to form the drain bias circuit of the PHEMT tube M4; wherein, after the vertical upper end of the T-type microstrip line T7 is connected to one end of the capacitor C14, it is used to be connected to the positive electrode of the DC power supply.

[0065] The vertical lower end and the vertical end of the T-type microstrip line T5, the capacitor C11 and the vertical lower end and the vertical end of the T-type microstrip line T6 form the inter-stage matching between the PHEMT tube M3 and the PHEMT tube M4.

[0066] The resistor R11, the capacitor C12, the resistor R12, the capacitor C13 and the capacitor C14 have the same functions as the resistor R9, the capacitor C8, the resistor R10, the capacitor C9 and the capacitor C10, respectively, but have different parameters.

[0067] The vertical lower end, the vertical end and the capacitor C15 of the T-type microstrip line T7 form the output matching of the PHEMT tube M4.

[0068] 2.2. The first amplifying branch and the second amplifying branch have the same structure, component parameters and performance. Figure 5 As shown, the structure of the second amplification branch is briefly described:

[0069] In the second amplifying branch, the third-stage amplifying circuit includes a PHEMT transistor M5, and the fourth-stage amplifying circuit includes a PHEMT transistor M6;

[0070] Among them, the RF signal RF from the folded Lange coupler is directly output in It enters the gate of the PHEMT tube M5 through the matching module 4, is amplified and output from the drain, enters the gate of the PHEMT tube M6 through the matching module 5, is output from the drain of the PHEMT tube M6, and enters the through input end of the folded Lange coupler 2 through the matching module 6;

[0071] The source of the PHEMT tube M5 is connected to a self-bias module 2, and the self-bias module 2 provides a source bias voltage for the PHEMT tube M5; the source of the PHEMT tube M6 is connected to a self-bias module 3, and the self-bias module 3 provides a source bias voltage for the PHEMT tube M6;

[0072] A negative feedback module 1 is connected between the drain and the gate of the PHEMT tube M5; a negative feedback module 2 is connected between the drain and the gate of the PHEMT tube M6;

[0073] The drain of the PHEMT tube M5 is connected to a feeding module 3, and the feeding module 3 provides a drain bias voltage for the PHEMT tube M5;

[0074] A feed module 4 is connected to the drain of the PHEMT tube M6, and the feed module 4 provides a drain bias voltage for the PHEMT tube M6;

[0075] The other ends of the feed module three and the feed module four are used to be connected to the positive pole of the DC power supply.

[0076] like Figure 5 As shown, in the second amplifying branch, the matching module 4 is composed of the vertical upper end and the vertical end of the T-type microstrip line T8 to form the input matching of the PHEMT tube M5; wherein the vertical upper end of the T-type microstrip line T8 is grounded to provide a gate zero bias voltage for the PHEMT tube M5; and the vertical end is connected to the gate of the PHEMT tube M5;

[0077] The second self-bias module is composed of a resistor R14 and a capacitor C17 connected in parallel to form a self-bias, and is connected to the drain of the PHEMT tube M5;

[0078] The self-bias module 3 is self-biased by a resistor R16 and a capacitor C21 connected in parallel, and is connected to the drain of the PHEMT tube M6;

[0079] The negative feedback module 1 is composed of the vertical lower end of the cascaded T-type microstrip line T8, the resistor R13 and the capacitor C16 to form a negative feedback loop;

[0080] The negative feedback module 2 is composed of the vertical upper end of the cascaded T-type microstrip line T10, the resistor R15 and the capacitor C20 to form a negative feedback loop;

[0081] The feed module 3 is composed of the vertical lower end of the T-type microstrip line T9 and the capacitor C18 to form the source bias circuit of the PHEMT tube M5; wherein, after the vertical lower end of the T-type microstrip line T9 is connected to one end of the capacitor C18, it is used to be connected to the positive electrode of the DC power supply;

[0082] The feed module 4 is composed of the vertical lower end of the T-type microstrip line T11 and the capacitor C22 to form the source bias circuit of the PHEMT tube M6; wherein, after the vertical lower end of the T-type microstrip line T11 is connected to one end of the capacitor C22, it is used to be connected to the positive electrode of the DC power supply;

[0083] The matching module 5 is composed of the vertical lower end and vertical end of the T-type microstrip line T9, the capacitor C19 and the vertical upper end and vertical end of the T-type microstrip line T10; wherein the vertical upper end of the T-type microstrip line T9 is connected to the source of the PHEMT tube M5, and the vertical end is connected to the vertical upper end and vertical end of the T-type microstrip line T10 through the capacitor C19; the vertical end of the T-type microstrip line T10 is connected to the gate of the PHEMT tube M6;

[0084] Matching module six is ​​composed of the vertical upper end, vertical end and capacitor C23 of the T-type microstrip line T11; wherein, the vertical upper end of the T-type microstrip line T11 is connected to the source of the PHEMT tube M6, and the vertical end is connected to the through input end of the Lange coupler two through the capacitor C23.

[0085] The first-stage amplifying branch and the second-stage amplifying branch are combined and outputted by a folded Lange coupler 2, Lange2.

[0086] Figure 6 The figure shows the return loss simulation results of the broadband low-noise amplifier. The figure shows the S11 and S22 parameters of the amplifier in the frequency range of 22-45GHz, representing the input and output return losses respectively.

[0087] Both S11 and S22 are less than -15dB, indicating that the amplifier has good broadband port characteristics and can effectively transmit signals with little reflection loss.

[0088] This also verifies the effectiveness of the matching module in the amplifier design, ensuring good matching of the signals at the input and output ends.

[0089] Figure 7 This figure shows the noise figure of the broadband low noise amplifier in the frequency range of 22-45GHz.

[0090] The noise figure is less than 2.7dB, which means that the amplifier has low noise performance and can effectively amplify the signal without introducing excessive noise.

[0091] This is related to the current multiplexing structure and input matching in the amplifier design, which reduces signal loss and noise introduction.

[0092] Figure 8 This figure shows the output gain simulation results of the broadband low-noise amplifier. The figure shows the output gain of the amplifier in the frequency range of 22-45GHz.

[0093] The output gain is greater than 26.7dB, which means that the amplifier can effectively amplify the signal and provide sufficient gain.

[0094] This is related to the multi-stage amplification circuit and matching module in the amplifier design, which realizes the step-by-step amplification of the signal and good power transmission.

[0095] Fig. 9 The simulation results of the output power 1dB compression point of the broadband low noise amplifier are shown in the figure. The figure shows the output power 1dB compression point of the amplifier in the frequency range of 22-45GHz.

[0096] The output power 1dB compression point is greater than 11dBm, indicating that the amplifier has good linearity and can still maintain the linear characteristics of the signal at higher power output.

[0097] This is related to the feedback module in the amplifier design, which effectively suppresses nonlinear distortion and ensures signal quality.

[0098] Figures 6 to 9The simulation results verify the performance of the broadband low noise amplifier of the present invention, proving that it has excellent performance in broadband characteristics, noise performance, gain and linearity, and can meet the high requirements of modern wireless communication technology for radio frequency receivers.

[0099] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0100] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A broadband low noise amplifier, characterized in that: include: Cascaded current multiplexing structure low noise amplifier and balanced low noise amplifier; Wherein, the current multiplexing low noise amplifier comprises: a first-stage amplifier circuit and a second-stage amplifier circuit which are cascaded in sequence; The balanced low-noise amplifier comprises: a folded Lange coupler 1, a folded Lange coupler 2, a first amplifying branch, and a second amplifying branch; one end of the first amplifying branch is connected to the coupling output end of the folded Lange coupler 1, and the other end is connected to the coupling input end of the folded Lange coupler 2; one end of the second amplifying branch is connected to the through output end of the folded Lange coupler 1, and the other end is connected to the through input end of the folded Lange coupler 2; The first amplifying branch and the second amplifying branch are both of the same two-stage amplifying circuit structure, including a cascaded third-stage amplifying circuit, a fourth-stage amplifying circuit, a negative feedback module 1 adapted to the third-stage amplifying circuit, and a negative feedback module 2 adapted to the fourth-stage amplifying circuit; The third-stage amplifier circuit and the fourth-stage amplifier circuit have the same amplifier circuit structure; The amplifier devices in each amplifier circuit all adopt PHEMT tubes, and the broadband low-noise amplifier is integrated on a single-chip gallium arsenide.

2. A broadband low noise amplifier according to claim 1, characterized in that: In the current multiplexing structure low noise amplifier: the first stage amplification circuit includes a PHEMT tube M1, and the second stage amplification circuit includes a PHEMT tube M2; Among them, the input radio frequency signal RF in It enters the gate of PHEMT tube M1 through matching module 1, is amplified and output from the drain, enters the gate of PHEMT tube M2 through interstage matching module 2, is output from the drain of PHEMT tube M2, and enters the input end of folded Lange coupler 1 through matching module 3; The source of the PHEMT tube M1 is connected to a self-bias module 1, and the self-bias module 1 provides a source bias voltage for the PHEMT tube M1; A current multiplexing module is connected between the drain of the PHEMT tube M1 and the source of the PHEMT tube M2; the current multiplexing module provides a DC path for the PHEMT tubes M1 and M2; The gate of the PHEMT tube M2 is connected to one end of the feeding module 1, and the feeding module 1 provides a gate bias voltage for the PHEMT tube M2; The drain of the PHEMT tube M2 is connected to one end of the feeding module 2, and the feeding module 2 provides a drain bias voltage for the PHEMT tube M2; The other ends of the feed module 1 and the feed module 2 are both used to be connected to the positive pole of the DC power supply.

3. A broadband low noise amplifier according to claim 2, characterized in that: The matching module 1 is composed of a cascaded capacitor C1 and a T-type microstrip line T1; wherein one end of the capacitor C1 is used to receive the radio frequency signal RF in , the other end is connected to the vertical end of the T-type microstrip line T1; the vertical lower end of the T-type microstrip line T1 is grounded, and the vertical upper end is connected to the gate of the PHEMT tube M1; The self-bias module 1 is composed of a resistor R1 and a capacitor C2 connected in parallel; The matching module 2 is composed of a microstrip line TL1, a capacitor C3 and a vertical lower end and a vertical end of a T-shaped microstrip line T2; wherein one end of the microstrip line TL1 is connected to the drain of the PHEMT tube M1, and the other end is connected to the vertical lower end of the T-shaped microstrip line T2 through the capacitor C3; the vertical end of the T-shaped microstrip line T2 is connected to the gate of the PHEMT tube M2; The matching module 3 is composed of a vertical lower end and a vertical end of a T-type microstrip line T3 and a capacitor C7; wherein the vertical lower end of the T-type microstrip line T3 is connected to the drain of the PHEMT tube M2, and the vertical end is connected to the input end of the folded Lange coupler 1 through the capacitor C7; The current multiplexing module is composed of microstrip lines TL1, TL2, TL3, a resistor R2 and a capacitor C4; wherein one end of the microstrip line TL1 is connected to the drain of the PHEMT tube M1, and the other end is connected to one end of the microstrip line TL2 through the resistor R2; the other end of the microstrip line TL2 is respectively connected to one end of the capacitor C4 and the microstrip line TL3; the other end of the capacitor C4 is grounded, and the other end of the microstrip line TL3 is connected to the source of the PHEMT tube M2; The feeding module 1 is composed of resistors R3, R4, R5, capacitor C5 and the vertical upper end and vertical end of the T-type microstrip line T2; wherein one end of the resistor R3 is used to be connected to the positive electrode of the DC power supply, and the other end is respectively connected to one end of the resistor R4, one end of the capacitor C5, and the vertical upper end of the T-type microstrip line T2; the other end of the resistor R4 is grounded; the other end of the capacitor C5 is grounded through the resistor R5; the vertical end of the T-type microstrip line T2 is connected to the gate of the PHEMT tube M2; The feeding module 2 is composed of resistors R6, R7, capacitor C6 and the vertical upper end and vertical lower end of the T-type microstrip line T3; wherein, the capacitor C6 and one end of the resistor R7 are connected and used to be connected to the positive electrode of the DC power supply; the other end of the capacitor C6 is grounded through the resistor R6; the other end of the resistor R7 is connected to the vertical upper end of the T-type microstrip line T3; the vertical lower end of the T-type microstrip line T3 is connected to the drain of the PHEMT tube M2.

4. A broadband low noise amplifier according to claim 1, characterized in that: In the first amplifying branch, the third-stage amplifying circuit includes a PHEMT transistor M3, and the fourth-stage amplifying circuit includes a PHEMT transistor M4; Among them, the radio frequency signal RF from the coupled output end of the folded Lange coupler is in It enters the gate of the PHEMT tube M3 through the matching module 4, is amplified and output from the drain, enters the gate of the PHEMT tube M4 through the matching module 5, is output from the drain of the PHEMT tube M4, and enters the coupling input end of the folded Lange coupler 2 through the matching module 6; The source of the PHEMT tube M3 is connected to a second self-bias module, and the second self-bias module provides a source bias voltage for the PHEMT tube M3; The source of the PHEMT tube M4 is connected to a self-bias module three, and the self-bias module three provides a source bias voltage for the PHEMT tube M4; A negative feedback module 1 is connected between the drain and the gate of the PHEMT tube M3; a negative feedback module 2 is connected between the drain and the gate of the PHEMT tube M4; A feed module 3 is connected to the drain of the PHEMT tube M3, and the feed module 3 provides a drain bias voltage for the PHEMT tube M3; A feed module 4 is connected to the drain of the PHEMT tube M4, and the feed module 4 provides a drain bias voltage for the PHEMT tube M4; The other ends of the feed module three and the feed module four are used to be connected to the positive pole of the DC power supply.

5. A broadband low noise amplifier according to claim 1, characterized in that: The folded Lange coupler 1 is the same as the folded Lange coupler 2, and both include an input port, a through port, a coupling port and an isolation port; During use, the signal is input from the input port, output from the through port and the coupled port, and the isolation port is cascaded with a resistor to ground.

6. A broadband low noise amplifier according to claim 4, characterized in that: The matching module 4 is composed of the vertical lower end and the vertical end of the T-type microstrip line T4 to form the input matching of the PHEMT tube M3; wherein the vertical lower end of the T-type microstrip line T4 is grounded to provide a gate zero bias voltage for the PHEMT tube M3; and the vertical end is connected to the gate of the PHEMT tube M3; The self-bias module 2 is self-biased by a resistor R10 and a capacitor C9 connected in parallel, and is connected to the source level of the PHEMT tube M3; The self-bias module 3 is self-biased by a resistor R12 and a capacitor C13 connected in parallel, and is connected to the source level of the PHEMT tube M4; The negative feedback module 1 is composed of a cascaded T-type microstrip line T4 vertical upper end, a resistor R9 and a capacitor C8 to form a negative feedback loop; The negative feedback module 2 is composed of a cascaded T-type microstrip line T6 vertical upper end, a resistor R11 and a capacitor C12 to form a negative feedback loop; The feed module 3 is composed of a vertical upper end of a T-shaped microstrip line T5 and a capacitor C10 to form a drain bias circuit of the PHEMT tube M3; wherein the vertical upper end of the T-shaped microstrip line T5 is connected to one end of the capacitor C10 and is used to be connected to the positive electrode of a DC power supply; The feed module 4 is composed of a vertical upper end of a T-shaped microstrip line T7 and a capacitor C14 to form a drain bias circuit of the PHEMT tube M4; wherein the vertical upper end of the T-shaped microstrip line T7 is connected to one end of the capacitor C14 and then connected to the positive electrode of the DC power supply; The matching module 5 is composed of the vertical lower end and vertical end of the T-type microstrip line T5, the capacitor C11 and the vertical lower end and vertical end of the T-type microstrip line T6; wherein the vertical lower end of the T-type microstrip line T5 is connected to the drain of the PHEMT tube M3, and the vertical end is connected to the vertical lower end and vertical end of the T-type microstrip line T6 through the capacitor C11; the vertical end of the T-type microstrip line T6 is connected to the gate of the PHEMT tube M4; The matching module 6 is composed of the vertical lower end, vertical end and capacitor C15 of the T-type microstrip line T7; wherein the vertical lower end of the T-type microstrip line T7 is connected to the drain of the PHEMT tube M4, and the vertical end is connected to the coupling input end of the folded Lange coupler 2 through the capacitor C15.

7. A broadband low noise amplifier according to claim 1, characterized in that: In the second amplifying branch, the third-stage amplifying circuit includes a PHEMT transistor M5, and the fourth-stage amplifying circuit includes a PHEMT transistor M6; Among them, the RF signal RF from the folded Lange coupler is directly output in It enters the gate of the PHEMT tube M5 through the matching module 4, is amplified and output from the drain, enters the gate of the PHEMT tube M6 through the matching module 5, is output from the drain of the PHEMT tube M6, and enters the through input end of the folded Lange coupler 2 through the matching module 6; The source of the PHEMT tube M5 is connected to a second self-bias module, and the second self-bias module provides a source bias voltage for the PHEMT tube M5; The source of the PHEMT tube M6 is connected to a self-bias module 3, and the self-bias module 3 provides a source bias voltage for the PHEMT tube M6; A negative feedback module 1 is connected between the drain and the gate of the PHEMT tube M5; a negative feedback module 2 is connected between the drain and the gate of the PHEMT tube M6; A feed module 3 is connected to the drain of the PHEMT tube M5, and the feed module 3 provides a drain bias voltage for the PHEMT tube M5; A feed module 4 is connected to the drain of the PHEMT tube M6, and the feed module 4 provides a drain bias voltage for the PHEMT tube M6; The other ends of the feed module three and the feed module four are used to be connected to the positive pole of the DC power supply.

8. A broadband low noise amplifier according to claim 7, characterized in that: In the second amplifying branch, the matching module 4 is composed of the vertical upper end and the vertical end of the T-type microstrip line T8 to form the input matching of the PHEMT tube M5; wherein the vertical upper end of the T-type microstrip line T8 is grounded to provide a gate zero bias voltage for the PHEMT tube M5; and the vertical end is connected to the gate of the PHEMT tube M5; The self-bias module 2 is self-biased by a resistor R14 and a capacitor C17 connected in parallel, and is connected to the drain of the PHEMT tube M5; The self-bias module 3 is self-biased by a resistor R16 and a capacitor C21 connected in parallel, and is connected to the drain of the PHEMT tube M6; The negative feedback module 1 is composed of a cascaded T-type microstrip line T8 vertical lower end, a resistor R13 and a capacitor C16 to form a negative feedback loop; The negative feedback module 2 is composed of a cascaded T-type microstrip line T10 vertical upper end, a resistor R15 and a capacitor C20 to form a negative feedback loop; The feed module 3 is composed of the vertical lower end of the T-shaped microstrip line T9 and the capacitor C18 to form a source bias circuit of the PHEMT tube M5; wherein the vertical lower end of the T-shaped microstrip line T9 is connected to one end of the capacitor C18 and is used to be connected to the positive electrode of the DC power supply; The feed module 4 is composed of the vertical lower end of the T-shaped microstrip line T11 and the capacitor C22 to form a source bias circuit of the PHEMT tube M6; wherein, after the vertical lower end of the T-shaped microstrip line T11 is connected to one end of the capacitor C22, it is used to be connected to the positive electrode of the DC power supply; The matching module 5 is composed of the vertical lower end and vertical end of the T-type microstrip line T9, the capacitor C19 and the vertical upper end and vertical end of the T-type microstrip line T10; wherein the vertical upper end of the T-type microstrip line T9 is connected to the source of the PHEMT tube M5, and the vertical end is connected to the vertical upper end and vertical end of the T-type microstrip line T10 through the capacitor C19; the vertical end of the T-type microstrip line T10 is connected to the gate of the PHEMT tube M6; The matching module 6 is composed of the vertical upper end, vertical end and capacitor C23 of the T-type microstrip line T11; wherein the vertical upper end of the T-type microstrip line T11 is connected to the source of the PHEMT tube M6, and the vertical end is connected to the through input end of the folded Lange coupler 2 through the capacitor C23.

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