A low noise amplifier and electronic device for a phased array system

Abstract

This invention provides a low-noise amplifier and electronic device for a phased array system, relating to the field of antenna technology. The input common-gate transistor is connected to the output common-gate transistor via an inductor-coupled transformer. The inductor-coupled transformer increases the transconductance of both the input and output common-gate transistors by utilizing the mutual coupling of its multiple inductors and adjusting the coupling coefficients between pairs of inductors. As the radio frequency signal is amplified by the input and output common-gate transistors with increased transconductance, noise is reduced, and the signal is then output to the subsequent circuitry by the output common-gate transistor. This invention achieves increased transconductance of the dual transistors, reduced noise figure, increased circuit gain, excellent circuit performance, and simplified input and noise matching. It also improves system integration, reduces chip area and power consumption, and indirectly reduces the cost of radio frequency millimeter-wave phased array systems.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more particularly to a low-noise amplifier and electronic device for phased array systems. Background Technology

[0002] Currently, low-noise amplifiers (LNAs) are commonly used as the first stage circuit in receivers to amplify weak signals received from the antenna, and are a key module determining the noise figure of the receiving system. With the development of phased array technology, large-scale, multi-channel phased array systems require a large number of LNA modules, making LNA power consumption and area important performance indicators. Therefore, LNAs used in phased array systems should not only meet the requirements of low noise and high gain, but also possess low power consumption and small area characteristics.

[0003] However, some existing LNAs use a traditional differential amplifier circuit structure. While their input balun achieves single-slip functionality for the input signal, this degrades noise and gain performance. Furthermore, the differential structure increases circuit power consumption. Some LNAs also employ a noise cancellation structure, which achieves low noise but increases chip area.

[0004] Therefore, there is an urgent need to propose an LNA structure suitable for phased array systems that can reduce the noise figure, increase circuit gain, and effectively reduce power consumption and area overhead. Summary of the Invention

[0005] In view of the above problems, the present invention is proposed to provide a low-noise amplifier and electronic device for a phased array system that solves or partially solves the above problems.

[0006] A first aspect of the present invention provides a low-noise amplifier for a phased array system, the low-noise amplifier comprising: an input common-gate transistor, an output common-gate transistor, and an inductor-coupled transformer;

[0007] The input common gate transistor is connected to the output common gate transistor through an inductor coil of the inductor coil coupling transformer, and the input common gate transistor receives radio frequency signals;

[0008] The inductor-coupled transformer increases the transconductance of the input common-gate transistor and the output common-gate transistor by utilizing the mutual coupling of its multiple inductors and adjusting the coupling coefficient between pairs of inductors.

[0009] The radio frequency signal is amplified by the input common gate transistor and the output common gate transistor after the transconductance is increased, while the noise is reduced, and then the output common gate transistor outputs the signal to the subsequent circuit.

[0010] Optionally, the inductor-coupled transformer includes: a first inductor, a second inductor, a third inductor, and a fourth inductor;

[0011] The first terminal of the first inductor is connected to the first terminal of the input common gate transistor and receives the radio frequency signal;

[0012] The second terminal of the first inductor is grounded;

[0013] The first terminal of the second inductor is connected to the second terminal of the input common-gate transistor;

[0014] The second terminal of the second inductor receives the bias voltage;

[0015] The first terminal of the third inductor is connected to the third terminal of the input common gate transistor;

[0016] The second terminal of the third inductor is connected to the first terminal of the output common gate transistor;

[0017] The second terminal of the fourth inductor is connected to the second terminal of the output common gate transistor;

[0018] The first terminal of the fourth inductor receives the power supply voltage.

[0019] Optionally, the low-noise amplifier further includes: a load inductor;

[0020] The first terminal of the load inductor receives the power supply voltage;

[0021] The third terminal of the output common gate transistor is connected to the second terminal of the load inductor, and the output noise is reduced and amplified radio frequency signal.

[0022] Optionally, the first inductor, the second inductor, the third inductor, and the fourth inductor are each implemented using on-chip metal.

[0023] Optionally, the first inductor and the second inductor are implemented by winding the first metal layer of the on-chip metal;

[0024] The third inductor is implemented by winding the second metal layer of the on-chip metal;

[0025] The fourth inductor is implemented by winding the third metal layer of the on-chip metal;

[0026] The first metal layer, the second metal layer, and the third metal layer are three adjacent metal layers of the on-chip metal.

[0027] Optionally, the first inductor, the second inductor, the third inductor, and the fourth inductor are coupled to each other, and the inductance values ​​of each inductor are adjustable.

[0028] The coupling coefficients between the first inductor and the second inductor, between the second inductor and the third inductor, between the third inductor and the fourth inductor, and between the fourth inductor and the first inductor are all adjustable.

[0029] Optionally, the value of the coupling coefficient, and the values ​​of the inductance of the first inductor, the second inductor, the third inductor, and the fourth inductor, are determined by the degree of increase in the transconductance of the input common gate transistor and the output common gate transistor.

[0030] Optionally, the inductance values ​​of the first inductor, the second inductor, the third inductor, and the fourth inductor can be adjusted by the length of their respective metal windings; the longer the winding, the greater the inductance value.

[0031] The coupling coefficient is adjusted by changing the relative distance and width of the metals corresponding to adjacent inductors.

[0032] Optionally, the load inductor is used to achieve impedance matching with the subsequent circuitry and to isolate the noise-reduced and amplified radio frequency signals.

[0033] A second aspect of the present invention provides an electronic device comprising a low-noise amplifier for a phased array system as described in any of the first aspects.

[0034] The low-noise amplifier for a phased array system provided by this invention includes: an input common-gate transistor, an output common-gate transistor, and an inductor-coupled transformer. The input common-gate transistor is connected to the output common-gate transistor through an inductor in the inductor-coupled transformer, and the input common-gate transistor receives radio frequency signals.

[0035] The inductor-coupled transformer utilizes the mutual coupling of its multiple inductors and adjusts the coupling coefficient between pairs of inductors to increase the transconductance of the input common gate transistor and the output common gate transistor. Finally, the radio frequency signal is amplified by the input common gate transistor and the output common gate transistor after the transconductance is increased, while the noise is reduced, and then the output common gate transistor outputs the signal to the subsequent circuit.

[0036] The low-noise amplifier proposed in this invention for phased array systems is an LNA based on a common-source, common-gate structure. By introducing an inductor-coil coupling transformer composed of multiple inductors and their coupling, the transconductance of both the input and output common-gate transistors is increased. This increase in transconductance significantly reduces the noise of the input RF signal, decreases the noise figure, increases the circuit gain, and achieves excellent amplifier circuit performance. At the same time, it simplifies the input matching and noise matching of the circuit.

[0037] Meanwhile, the inductor-coupled structure improves system integration, reduces chip area and power consumption, and indirectly lowers the implementation cost of RF millimeter-wave phased array systems. In summary, the low-noise amplifier for phased array systems proposed in this invention has extremely high practicality. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a circuit structure diagram of a low-noise amplifier for a phased array system, exemplified by an NMOS transistor, in an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of a structure of four inductively coupled coils, exemplified by metal layers M8, M9 and AP, in an embodiment of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] This invention proposes a low-noise amplifier for a phased array system, comprising: an input common-gate transistor, an output common-gate transistor, and an inductor-coupled transformer. The input common-gate transistor is connected to the output common-gate transistor through an inductor in the inductor-coupled transformer, and the input common-gate transistor receives radio frequency signals.

[0043] The inductor-coupled transformer utilizes the mutual coupling of its multiple inductors and adjusts the coupling coefficient between pairs of inductors to increase the transconductance of the input common gate transistor and the output common gate transistor. Finally, the radio frequency signal is amplified by the input common gate transistor and the output common gate transistor after the transconductance is increased, while the noise is reduced, and then the output common gate transistor outputs the signal to the subsequent circuit.

[0044] The LNA of this invention does not employ a traditional differential amplifier circuit structure, nor does it differ from the traditional noise cancellation structure. Instead, it creatively introduces an inductor-coupled transformer composed of multiple inductors and their couplings to increase the transconductance of both the input and output common-gate transistors. This increased transconductance significantly reduces the noise of the input RF signal, decreases the noise figure, increases the circuit gain, and achieves excellent amplifier circuit performance. At the same time, it simplifies the input matching and noise matching of the circuit.

[0045] Meanwhile, the inductor-coupled structure improves the system's integration, reduces chip area and power consumption, and indirectly lowers the implementation cost of the RF millimeter-wave phased array system.

[0046] In some possible embodiments, the inductor-coupled transformer includes a first inductor, a second inductor, a third inductor, and a fourth inductor. A first terminal of the first inductor is connected to a first terminal of the input common-gate transistor and receives a radio frequency signal; a second terminal of the first inductor is grounded; a first terminal of the second inductor is connected to a second terminal of the input common-gate transistor; and a second terminal of the second inductor receives a bias voltage.

[0047] The first terminal of the third inductor is connected to the third terminal of the input common-gate transistor; the second terminal of the third inductor is connected to the first terminal of the output common-gate transistor; the second terminal of the fourth inductor is connected to the second terminal of the output common-gate transistor; and the first terminal of the fourth inductor receives the power supply voltage.

[0048] The above structure enables the four inductors connected to the two transistors to couple with each other, and the coupling coefficients between each pair can be adjusted, forming a four-coil coupling transformer. This four-coil coupling transformer can increase the transconductance of both the input and output common-gate transistors, effectively improving the low-noise performance of the LNA amplifier.

[0049] In some possible embodiments, the low-noise amplifier further includes: a load inductor; a first terminal of the load inductor receiving a power supply voltage; a third terminal of the output common-gate transistor connected to a second terminal of the load inductor, and outputting a radio frequency signal with reduced noise and amplified.

[0050] To better explain and illustrate the low-noise amplifier for phased array systems proposed in this invention, refer to... Figure 1 The diagram shows a circuit structure of a low-noise amplifier for a phased array system. Figure 1 The circuit diagram is shown using an NMOS transistor as an example. Those skilled in the art will understand that other components with the same function, such as PMOS transistors and triodes, can achieve the same result with simple modifications. Figure 1 The circuit structure and its working principle are shown, but will not be shown in detail again.

[0051] Figure 1 It includes: input common gate transistor M1, output common gate transistor M2, first inductor Ls, second inductor Lg1, third inductor Ld1, fourth inductor Lg2, and load inductor Ld2.

[0052] The first terminal of the first inductor Ls is connected to the source of the input common-gate transistor M1, through which the radio frequency signal RFin is input. The second terminal of the first inductor Ls is grounded. The gate of the input common-gate transistor M1 is connected to the first terminal of the second inductor Lg1, and the second terminal of the second inductor Lg1 receives the bias voltage Vb.

[0053] The drain of the input common-gate transistor M1 is connected to the first terminal of the third inductor Ld1, the second terminal of the third inductor Ld1 is connected to the source of the output common-gate transistor M2, and the gate of the output common-gate transistor M2 is connected to the second terminal of the fourth inductor Lg2, the first terminal of the fourth inductor Lg2 receiving the power supply voltage VDD. The drain of the output common-gate transistor M2 is connected to the second terminal of the load inductor Ld2, the first terminal of the load inductor Ld2 also receiving the power supply voltage VDD. The output common-gate transistor M2 outputs a noise-reduced and amplified radio frequency signal RFout.

[0054] Figure 1 The coupling coefficients between each pair of the four coils are exemplarily represented by Ksg1, Ksd1, Kg1d1, and Kg2d1, respectively. The load inductor Ld2 is used to connect with the subsequent circuit (i.e., the circuit that uses the RF signal RFout as its input signal). Figure 1 For the sake of simplicity in the illustration, impedance matching (not shown) and the RF signal RFout used to isolate noise reduction and amplification are also shown. This is because if there were no load inductor Ld2, the RF signal RFout might be output through the power supply voltage terminal instead of to the subsequent circuitry.

[0055] The values ​​of the coupling coefficients between each of the four inductors, as well as the values ​​of the inductance of the first, second, third, and fourth inductors, are determined by the degree of increase in the transconductance of the input and output common-gate transistors.

[0056] It should be noted that, Figure 1 The example shown is of four inductors with coils coupled at opposite ends. For coils coupled at the same ends, those skilled in the art can obtain the form through simple transformation and derivation, and it will not be shown separately.

[0057] In some possible embodiments, the circuit of the low-noise amplifier for a phased array system proposed in this invention, wherein the four mutually coupled inductors—the first inductor, the second inductor, the third inductor, the fourth inductor, and the load inductor—are all implemented by on-chip metal.

[0058] The first and second inductors are implemented by winding the first metal layer of the on-chip metal, that is, the first and second inductors are located on the same metal layer; the third inductor is implemented by winding the second metal layer of the on-chip metal; the fourth inductor is implemented by winding the third metal layer of the on-chip metal; wherein the first metal layer, the second metal layer, and the third metal layer are three adjacent metal layers of the on-chip metal.

[0059] To better explain and illustrate the circuit structure implemented with on-chip metal described above, refer to... Figure 2 The diagram shows an exemplary 4-inductively coupled coil structure. Figure 2 Using metal layers M8, M9, and AP as examples, this diagram schematically illustrates a structure where three inductors are implemented using on-chip metal. Those skilled in the art will understand that any three other adjacent metal layers can achieve the same result. Figure 2 The structures and their working principles shown are not illustrated in detail here.

[0060] Figure 2 The first inductor Ls and the second inductor Lg1 are wound from the metal layer M9 of the on-chip metal. Figure 2 The third inductor, Ld1, is made of a metal layer M8 on the chip (in black form). Figure 2 The fourth inductor, Lg2, is achieved by winding the top metal layer AP of the on-chip metal (with a mesh-like structure). Figure 2 (Achieved using the slash shape).

[0061] With the above-described on-chip metal structure, the first inductor Ls, the second inductor Lg1, the third inductor Ld1, and the fourth inductor Lg2 are mutually coupled, and their respective inductance values ​​are adjustable; furthermore, the coupling coefficients between the first inductor Ls and the second inductor Lg1, between the second inductor Lg1 and the third inductor Ld1, between the third inductor Ld1 and the fourth inductor Lg2, and between the fourth inductor Lg2 and each of the first inductors Ls are all adjustable.

[0062] As described earlier, the coupling coefficients between each of the four inductors, as well as the individual inductance values ​​of the first inductor Ls, the second inductor Lg1, the third inductor Ld1, and the fourth inductor Lg2, are determined by the increase in the transconductance of the input common-gate transistor M1 and the output common-gate transistor M2. In the on-chip metal implementation, the inductance values ​​of the first inductor Ls, the second inductor Lg1, the third inductor Ld1, and the fourth inductor Lg2 are adjusted by the length of their respective metal windings; the longer the length, the larger the inductance. That is, the longer the metal winding of the first inductor Ls, the larger its inductance; the shorter the metal winding of the first inductor Ls, the smaller its inductance. The same applies to the other three inductors.

[0063] The coupling coefficient between any two inductors is generally adjusted by changing the relative distance and width of the corresponding metal parts of adjacent inductors. For example, the coupling coefficient between the first inductor Ls and the second inductor Lg1 can be adjusted by changing the relative distance between the metal parts corresponding to the first inductor Ls and the second inductor Lg1, as well as by changing the width of the metal parts corresponding to the first inductor Ls and the second inductor Lg1. The adjustment of the coupling coefficient between other pairs of inductors follows the same principle and will not be elaborated further.

[0064] Furthermore, the low-noise amplifier for phased array systems proposed in this invention can be extended to other applications. For example, assuming the input RF signal is a differential input signal, two sets of... Figure 1 The circuit structure shown has one set of circuits receiving one differential signal and another set receiving the other differential signal. The output RF signal, with reduced noise and amplified, is also a differential output signal. This design is well-suited for antenna structures that transmit and receive signals in differential form.

[0065] Based on the low-noise amplifiers for phased array systems described above, the present invention also proposes an electronic device comprising any of the low-noise amplifiers for phased array systems described above.

[0066] Through the above examples, the low-noise amplifier for phased array systems provided by the present invention includes: an input common-gate transistor, an output common-gate transistor, and an inductor-coupled transformer. The input common-gate transistor is connected to the output common-gate transistor through an inductor in the inductor-coupled transformer, and the input common-gate transistor receives radio frequency signals.

[0067] The inductor-coupled transformer utilizes the mutual coupling of its multiple inductors and adjusts the coupling coefficient between pairs of inductors to increase the transconductance of the input common gate transistor and the output common gate transistor. Finally, the radio frequency signal is amplified by the input common gate transistor and the output common gate transistor after the transconductance is increased, while the noise is reduced, and then the output common gate transistor outputs the signal to the subsequent circuit.

[0068] The low-noise amplifier proposed in this invention for phased array systems is an LNA based on a common-source, common-gate structure. By introducing an inductor-coil coupling transformer composed of multiple inductors and their coupling, the transconductance of both the input and output common-gate transistors is increased. This increase in transconductance significantly reduces the noise of the input RF signal, decreases the noise figure, increases the circuit gain, and achieves excellent amplifier circuit performance. At the same time, it simplifies the input matching and noise matching of the circuit.

[0069] Meanwhile, the inductor-coupled structure improves system integration, reduces chip area and power consumption, and indirectly lowers the implementation cost of RF millimeter-wave phased array systems. In summary, the low-noise amplifier for phased array systems proposed in this invention has extremely high practicality.

[0070] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0071] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A low-noise amplifier for a phased array system, characterized in that, The low-noise amplifier includes: an input common-gate transistor, an output common-gate transistor, an inductor coupling transformer, and a load inductor; The input common gate transistor is connected to the output common gate transistor through an inductor coil of the inductor coil coupling transformer, and the input common gate transistor receives radio frequency signals; The inductor-coupled transformer increases the transconductance of the input common-gate transistor and the output common-gate transistor by utilizing the mutual coupling of its multiple inductors and adjusting the coupling coefficient between pairs of inductors. The radio frequency signal is amplified by the input common gate transistor and the output common gate transistor after the transconductance is increased, while the noise is reduced, and then the output common gate transistor outputs the signal to the subsequent circuit. The inductor coil coupling transformer includes: a first inductor, a second inductor, a third inductor, and a fourth inductor; The first terminal of the first inductor is connected to the first terminal of the input common-gate transistor and receives the radio frequency signal; the second terminal of the first inductor is grounded; the first terminal of the second inductor is connected to the second terminal of the input common-gate transistor; the second terminal of the second inductor receives a bias voltage; the first terminal of the third inductor is connected to the third terminal of the input common-gate transistor; the second terminal of the third inductor is connected to the first terminal of the output common-gate transistor; the second terminal of the fourth inductor is connected to the second terminal of the output common-gate transistor; the first terminal of the fourth inductor receives a power supply voltage. The first terminal of the load inductor receives the power supply voltage; the third terminal of the output common gate transistor is connected to the second terminal of the load inductor, and outputs a radio frequency signal with reduced noise and amplified.

2. The low-noise amplifier according to claim 1, characterized in that, The first inductor, the second inductor, the third inductor, and the fourth inductor are each implemented using on-chip metal.

3. The low-noise amplifier according to claim 2, characterized in that, The first inductor and the second inductor are implemented by winding the first metal layer of the on-chip metal; The third inductor is implemented by winding the second metal layer of the on-chip metal; The fourth inductor is implemented by winding the third metal layer of the on-chip metal; The first metal layer, the second metal layer, and the third metal layer are three adjacent metal layers of the on-chip metal.

4. The low-noise amplifier according to claim 3, characterized in that, The first inductor, the second inductor, the third inductor, and the fourth inductor are coupled to each other, and the inductance values ​​of each inductor are adjustable. The coupling coefficients between the first inductor and the second inductor, between the second inductor and the third inductor, between the third inductor and the fourth inductor, and between the fourth inductor and the first inductor are all adjustable.

5. The low-noise amplifier according to claim 1, characterized in that, The value of the coupling coefficient, as well as the values ​​of the inductance of the first inductor, the second inductor, the third inductor, and the fourth inductor, are determined by the degree of increase in the transconductance of the input common gate transistor and the output common gate transistor.

6. The low-noise amplifier according to claim 4, characterized in that, The inductance values ​​of the first inductor, the second inductor, the third inductor, and the fourth inductor are adjusted by the length of their respective metal windings; the longer the winding, the greater the inductance value. The coupling coefficient is adjusted by changing the relative distance and width of the metals corresponding to adjacent inductors.

7. The low-noise amplifier according to claim 1, characterized in that, The load inductor is used to achieve impedance matching with the subsequent circuitry and to isolate the noise-reduced and amplified radio frequency signals.

8. An electronic device, characterized in that, The electronic device includes a low-noise amplifier for a phased array system as described in any one of claims 1-7.

Images