A broadband low-noise amplifier

Abstract

The present invention discloses a broadband low-noise amplifier, belonging to the technical field of monolithic microwave integrated circuits; it includes: a current-reused structure low-noise amplifier and a balanced low-noise amplifier connected in cascade; the current-reused low-noise amplifier includes: a first-stage and a second-stage amplifier circuits connected in cascade in sequence; the balanced low-noise amplifier includes: two folded Lange couplers and two amplification branches; both of the two amplification branches are of the same two-stage amplifier circuit structure, including a third-stage and a fourth-stage amplifier circuits of the same structure connected in cascade; the amplification devices in each amplifier circuit all adopt PHEMT transistors, and the broadband low-noise amplifier is integrated on a monolithic gallium arsenide. The present invention effectively reduces the noise figure, reduces the power consumption, reduces the layout area, and improves the performance of the traditional balanced low-noise amplifier by combining the current-reused technology, the Lange coupler folding technology, the negative feedback technology, and the balanced structure.

Description

Technical Field

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

[0002] With the rapid development of modern wireless communication technologies, the requirements for the noise, bandwidth, and miniaturization of radio frequency receivers in communication are also getting higher and higher. As one of the most critical devices in the front-end of radio frequency receivers, a low-noise amplifier (LNA) can reduce noise crosstalk and provide a certain gain to the radio frequency signals received by the antenna, and its performance directly affects the overall performance of broadband receivers.

[0003] The traditional balanced low-noise amplifier is a common broadband low-noise amplifier. This structure provides a good port voltage standing wave ratio. However, the radio frequency signal first passes through a Lange coupler and then enters the amplification circuit, making it difficult to reduce the overall noise and power consumption, and the chip area is very large, resulting in high manufacturing costs. Therefore, the structure needs to be optimized to reduce the noise figure, power consumption, and chip area.

[0004] In summary, the traditional balanced low-noise amplifier structure has problems such as a high noise figure, large power consumption, and large layout area, which limit 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 the low-noise amplifier structure in the above-mentioned prior art, such as high noise figure, large power consumption, and large layout area. By combining current reuse technology, Lange coupler folding technology, negative feedback technology, and a balanced structure, the present invention effectively reduces the noise figure, power consumption, and layout area, and improves the performance of the traditional balanced low-noise amplifier.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A broadband low-noise amplifier provided by an embodiment of the present invention includes: a current reuse structure low-noise amplifier and a balanced low-noise amplifier connected in cascade;

[0008] Wherein, the current reuse low-noise amplifier includes: a first-stage amplification circuit and a second-stage amplification circuit connected in cascade in sequence;

[0009] The balanced low-noise amplifier includes: a folded Lange coupler 1, a folded Lange coupler 2, a first amplification branch, and a second amplification branch. One end of the first amplification branch is connected to the coupled output end of the folded Lange coupler 1, and the other end is connected to the coupled input end of the folded Lange coupler 2. One end of the second amplification 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] Both the first amplification branch and the second amplification branch have the same two-stage amplification circuit structure, including a cascaded third-stage amplification circuit, a fourth-stage amplification circuit, a negative feedback module 1 adapted to the third-stage amplification circuit, and a negative feedback module 2 adapted to the fourth-stage amplification circuit.

[0011] The third-stage amplification circuit and the fourth-stage amplification circuit have the same amplification circuit structure.

[0012] The amplification devices in each amplification circuit all use PHEMT transistors, and the broadband low-noise amplifier is integrated on a monolithic gallium arsenide.

[0013] Through the above technical solutions, compared with the prior art, the present invention has the following advantages:

[0014] 1. Small noise figure: In this solution, the RF signal directly enters the first-stage amplification circuit, rather than the RF signal first passing through the Lange coupler and then entering the first-stage amplification circuit, avoiding the relatively high noise figure caused by the self-loss of the Lange coupler.

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

[0016] 3. Miniaturization: The current reuse structure low-noise amplifier has a simple circuit and convenient 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 filtering capacitors in the power supply modules 1 and 2 are connected in series with resistors to ground, and the negative feedback modules in the third and fourth-stage amplification circuits improve the stability of the overall circuit.

[0018] 5. Good broadband characteristics: The matching module 1 in the current reuse structure low-noise amplifier uses broadband matching to achieve broadband characteristics. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to the provided drawings.

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

[0021] Figure 2 It is a schematic diagram of the structure of the current-reused structure low-noise amplifier provided by the present invention;

[0022] Figure 3 It is a schematic diagram of the first amplification branch structure of the balanced low-noise amplifier provided by the present invention;

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

[0024] Figure 5 It is a circuit schematic diagram of the broadband low-noise amplifier in the specific embodiment provided by the present invention;

[0025] Figure 6 It is a simulation result diagram of the return loss of the broadband low-noise amplifier in the specific embodiment provided by the present invention;

[0026] Figure 7 It is a simulation result diagram of the noise figure of the broadband low-noise amplifier in the specific embodiment provided by the present invention;

[0027] Figure 8 It is a simulation result diagram of the output gain of the broadband low-noise amplifier in the specific embodiment provided by the present invention;

[0028] Figure 9 It is a simulation result diagram of the 1dB compression point of the output power of the broadband low-noise amplifier in the specific embodiment provided by the present invention. Specific Embodiment

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0030] The present invention effectively reduces the noise figure, power consumption, and layout area, and improves the performance of a traditional balanced low-noise amplifier by combining current reuse technology, Lange coupler folding technology, negative feedback technology, and a balanced structure.

[0031] In related technologies, due to the sharing of current by transistors in the current reuse structure, the power consumption of the circuit can be effectively reduced. At the same time, the outputs can be superimposed with the gains of each stage, enabling a higher gain improvement efficiency for the low-noise amplifier without increasing additional current. Additionally, the requirement for an independent bias circuit is reduced, resulting in a decrease in chip area and the complexity of the peripheral circuit. However, achieving broadband characteristics requires a complex input-output matching structure. The present invention is configured with multiple matching modules.

[0032] The size of the Lange coupler has a direct relationship with its operating frequency band. The coupled line width and coupled spacing are very small compared to the coupled line length, resulting in a large aspect ratio of the Lange coupler size, which will cause a large area waste during the chip layout. Therefore, by folding the Lange coupler, the present invention can facilitate the layout while ensuring performance, achieving miniaturization of the low-noise amplifier.

[0033] In addition, the frequency response of the amplifier is mainly limited by the parasitic parameters of the transistors. Among them, 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 cut-off 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] Combining the above structures, the present invention can achieve a lower noise figure, lower power consumption, and smaller layout area for the low-noise amplifier.

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

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

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

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

[0039] For example, the first amplification branch is as Figure 3 shown. The third-stage amplification circuit includes PHEMT transistor M3, and the fourth-stage amplification circuit includes PHEMT transistor M4; the RF signal RF from the coupled output end of folded Lange coupler one in enters the gate of PHEMT transistor M3 through matching module four, is amplified and output from the drain, enters the gate of PHEMT transistor M4 through matching module five, is output from the drain of PHEMT transistor M4, and enters the coupled input end of folded Lange coupler two through matching module six; the self-bias module two is connected to the source of PHEMT transistor M3, and the self-bias module three is connected to the source of PHEMT transistor M4 to provide a source bias voltage for the PHEMT transistor; the negative feedback module one is connected between the drain and the gate of PHEMT transistor M3, and the negative feedback module two is connected between the drain and the gate of PHEMT transistor 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 PHEMT transistor M3, and the feeding module four provides a drain bias voltage for PHEMT transistor M4.

[0040] The above-mentioned folded Lange coupler one and folded Lange coupler two are as Figure 4As shown, the parameters such as the line width, line length, and line spacing of the two are the same. The structure includes an input port (Input), a through port (Through), a coupled port (Coupled), and an isolated port (Isolated). During actual use, the signal is input from the input port, and output from the through port and the coupled port. The isolated port is cascaded with a 50Ω resistor to the ground. The folded Lange coupler adopts a bent structure, reducing the size in the vertical direction, facilitating the layout of the layout, and reducing the overall layout area.

[0041] The present invention adopts a current reuse structure, where the RF signal directly enters the amplifier circuit, avoiding the loss of the Lange coupler and reducing the noise figure. Moreover, the current reuse structure reduces the power consumption of the circuit, while having a higher output gain. In addition, the current reuse structure simplifies the circuit layout, and the folded Lange coupler reduces the chip area, achieving miniaturization. A feeding module with a filtering capacitor in series with a resistor and a negative feedback module are added to improve the circuit stability. Finally, the current reuse structure adopts broadband matching, enabling good broadband characteristics.

[0042] The following combines Figure 5 the circuit schematic diagram to detail each of the above modules of the present invention:

[0043] As Figure 5 shown, it is the circuit schematic diagram of a broadband low-noise amplifier, including a cascaded current reuse structure low-noise amplifier and a balanced low-noise amplifier. The current reuse 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 first folded Lange coupler, a second folded Lange coupler, a first amplification branch connected to the coupled output end of the first folded Lange coupler and the coupled input end of the second folded Lange coupler, and a second amplification branch connected to the through output end of the first folded Lange coupler and the through input end of the second folded Lange coupler. All the amplifying devices in the broadband low-noise amplifier adopt PHEMT transistors, and the entire amplifier circuit is integrated on a single GaAs chip.

[0044] 1. Current reuse structure low-noise amplifier:

[0045] In the current reuse structure low-noise amplifier, the first-stage amplifier circuit includes PHEMT transistor M1, and the second-stage amplifier circuit includes PHEMT transistor M2.

[0046] Specifically, the cascaded capacitor C1 and the T-shaped microstrip transmission line T1 constitute the input matching of PHEMT transistor M1, for receiving the RF input signal RF in and performing broadband impedance matching on the RF input signal RF in to obtain a broadband matching signal; capacitor C1 is used to isolate the DC signal; the vertical lower end of the T-shaped microstrip line T1 is grounded, providing a zero bias voltage for the gate of PHEMT transistor M1.

[0047] The parallel-connected resistor R1 and capacitor C2 form a self-bias and are connected to the source of the PHEMT transistor M1; the resistor R1 is used for voltage division to provide a source bias voltage for the PHEMT transistor M1; the capacitor C2 is used to transmit the RF signal to ground.

[0048] The microstrip line TL1, capacitor C3, and the vertical lower end and vertical end of the T-shaped microstrip line T2 form the inter-stage matching between the PHEMT transistor M1 and the PHEMT transistor M2; the capacitor C3 is used to isolate the gate bias voltage of the PHEMT transistor M2 and the drain voltage of the PHEMT transistor M1, ensuring their difference.

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

[0050] The microstrip lines (TL1, TL2, TL3), resistor R2, and capacitor C4 form the DC path of the PHEMT transistor M1 and the PHEMT transistor M2, providing a suitable DC bias for the PHEMT transistor and filtering the RF signal in the DC path.

[0051] The resistors (R3, R4, R5), capacitor C5, and the vertical upper end and vertical end of the T-shaped microstrip line T2 form the gate bias circuit of the PHEMT transistor M2, which is used to provide a gate bias voltage; the resistors (R3, R4) are used to divide the DC voltage to provide a suitable output voltage value; the capacitor C5 and resistor R5 are used to filter out high-frequency noise to ensure voltage stability; the vertical upper end of the T-shaped microstrip line T2 is used as a choke inductor to block the transmission of RF signals.

[0052] The resistors (R6, R7), capacitor C6, and the vertical upper end and vertical lower end of the T-shaped microstrip line T3 form the drain bias circuit of the PHEMT transistor M2, which is used to provide a drain bias voltage; the resistor R6 and capacitor C6 are used to filter out high-frequency noise to ensure voltage stability; the resistors (R1, R2, R7) are jointly used for voltage division in the DC path; the vertical upper end of the T-shaped microstrip line T3 is used as a choke inductor to block the transmission of RF signals.

[0053] 2. Balanced low-noise amplifier:

[0054] The balanced low-noise amplifier includes a folded Lange coupler - one, a folded Lange coupler - two, a first amplification branch connected to the coupled output end of the folded Lange coupler - one and the coupled input end of the folded Lange coupler - two, and a second amplification branch connected to the through output end of the folded Lange coupler - one and the through input end of the folded Lange coupler - two.

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

[0056] 2.1. The first amplification branch and the second amplification branch are exactly the same. Taking the first amplification branch as an example, the details are as follows:

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

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

[0059] The parallel resistors R10 and capacitor C9 form a self-bias and are connected to the source of the PHEMT transistor M3; the resistor R10 is used for voltage division to provide a source bias voltage for the PHEMT transistor M3; the capacitor C9 is used to transmit the RF signal to the ground.

[0060] Similarly, the parallel resistors R12 and capacitor C13 form a self-bias and are connected to the source of the PHEMT transistor M4; the resistor R12 is used for voltage division to provide a source bias voltage for the PHEMT transistor M4; the capacitor C13 is used to transmit the RF signal to the ground.

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

[0062] As Figure 5 shown, and the negative feedback module 2 consists of the cascaded vertical upper end of the T-shaped microstrip line T6, resistor R11, and 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 the drain bias circuit of the PHEMT transistor M3 to provide a drain bias voltage.

[0064] As Figure 5As shown, the fourth feeding module is composed of the vertical upper end of the T-shaped microstrip line T7 and the capacitor C14 to form the drain bias circuit of the PHEMT transistor M4. Among them, after the vertical upper end of the T-shaped microstrip line T7 is connected to one end of the capacitor C14, it is used to connect to the positive pole of the DC power supply.

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

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

[0067] The vertical lower end, vertical end of the T-shaped microstrip line T7, and the capacitor C15 constitute the output matching of the PHEMT transistor M4.

[0068] 2.2. The structures, component parameters, and performances of the first amplification branch and the second amplification branch are the same. According to Figure 5 As shown, briefly describe the structure of the second amplification branch:

[0069] In the second amplification branch, the third-stage amplification circuit includes the PHEMT transistor M5, and the fourth-stage amplification circuit includes the PHEMT transistor M6.

[0070] Among them, the radio frequency signal RF in from the through output end of the folded Lange coupler enters the gate of the PHEMT transistor M5 through the fourth matching module, is amplified and then output from the drain, enters the gate of the PHEMT transistor M6 through the fifth matching module, is output from the drain of the PHEMT transistor M6, and enters the through input end of the second folded Lange coupler through the sixth matching module.

[0071] The source of the PHEMT transistor M5 is connected with a second self-bias module, and the second self-bias module provides a source bias voltage for the PHEMT transistor M5; the source of the PHEMT transistor M6 is connected with a third self-bias module, and the third self-bias module provides a source bias voltage for the PHEMT transistor M6.

[0072] A first negative feedback module is connected between the drain and the gate of the PHEMT transistor M5; a second negative feedback module is connected between the drain and the gate of the PHEMT transistor M6.

[0073] A third feeding module is connected to the drain of the PHEMT transistor M5, and the third feeding module provides a drain bias voltage for the PHEMT transistor M5.

[0074] A fourth feeding module is connected to the drain of the PHEMT transistor M6, and the fourth feeding module provides a drain bias voltage for the PHEMT transistor M6.

[0075] The other ends of the third and fourth power feeding modules are both used to be connected to the positive pole of the DC power supply.

[0076] As Figure 5 shown, in the second amplification branch, the fourth matching module is composed of the vertical upper end and the vertical end of the T-shaped microstrip line T8 to form the input matching of the PHEMT transistor M5; among them, the vertical upper end of the T-shaped microstrip line T8 is grounded to provide the gate zero bias voltage for the PHEMT transistor M5; the vertical end is connected to the gate of the PHEMT transistor M5;

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

[0078] The third self-bias module is composed of the parallel-connected resistor R16 and capacitor C21 to form self-bias, and is connected to the drain of the PHEMT transistor M6;

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

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

[0081] The third power feeding module is composed of the vertical lower end of the T-shaped microstrip line T9 and capacitor C18 to form the source bias circuit of the PHEMT transistor M5; among them, after the vertical lower end of the T-shaped microstrip line T9 is connected to one end of the capacitor C18, it is used to be connected to the positive pole of the DC power supply;

[0082] The fourth power feeding module is composed of the vertical lower end of the T-shaped microstrip line T11 and capacitor C22 to form the source bias circuit of the PHEMT transistor M6; among them, 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 pole of the DC power supply;

[0083] The fifth matching module is composed of the vertical lower end and the vertical end of the T-shaped microstrip line T9, capacitor C19 and the vertical upper end and the vertical end of the T-shaped microstrip line T10; among them, the vertical upper end of the T-shaped microstrip line T9 is connected to the source of the PHEMT transistor M5, and the vertical end is connected to the vertical upper end and the vertical end of the T-shaped microstrip line T10 through the capacitor C19; the vertical end of the T-shaped microstrip line T10 is connected to the gate of the PHEMT transistor M6;

[0084] The sixth matching module is composed of the vertical upper end, the vertical end of the T-shaped microstrip line T11 and capacitor C23; among them, the vertical upper end of the T-shaped microstrip line T11 is connected to the source of the PHEMT transistor M6, and the vertical end is connected to the through input end of the Lange coupler II through the capacitor C23.

[0085] The first - stage amplification branch and the second - stage amplification branch are combined and output by the folded Lange coupler two (Lange2).

[0086] Figure 6 It is the simulation result of the return loss of the broadband low - noise amplifier. This figure shows the S11 and S22 parameters of the amplifier in the frequency range of 22 - 45 GHz, which represent the return loss of the input and output respectively.

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

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

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

[0090] The noise figure is less than 2.7 dB, indicating that the amplifier has low noise performance and can effectively amplify signals without introducing too much noise.

[0091] This is related to the current - reuse structure and input matching in the amplifier design, reducing signal loss and noise introduction.

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

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

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

[0095] Figure 9 It is the simulation result of the 1 - dB compression point of the output power of the broadband low - noise amplifier. This figure shows the 1 - dB compression point of the output power of the amplifier in the frequency range of 22 - 45 GHz.

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

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

[0098] Figures 6 to 9The simulation results verify the performance of the broadband low-noise amplifier of the present invention, demonstrating its excellent performance in terms of broadband characteristics, noise performance, gain, and linearity, and meeting the high requirements of modern wireless communication technologies for RF receivers.

[0099] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method section.

[0100] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can 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 will be accorded 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 use PHEMT tubes, and the broadband low-noise amplifier is integrated on a single-chip gallium arsenide; Wherein, 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.

2. A broadband low noise amplifier according to claim 1, 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; 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.

3. 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; The RF signal from the coupled output end of the folded Lange coupler 1 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 coupled 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.

4. 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.

5. A broadband low noise amplifier according to claim 3, 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.

6. 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; The RF signal from the direct output end of the folded Lange coupler 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 direct 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.

7. A broadband low noise amplifier according to claim 6, 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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