High-integration-level low-noise amplifier circuit supporting dual-mode dual-frequency application

Abstract

The invention provides a high-integration low-noise amplifier circuit supporting dual-mode dual-frequency application, and the circuit comprises a first input stage which is used for receiving a first frequency band radio frequency signal; the second input stage is used for receiving a second frequency band radio frequency signal; the output stage is respectively connected with the first input stage and the second input stage; wherein the first input stage and the second input stage share a feedback inductor and a load network of the output stage to achieve impedance matching. Double-end input and single-end output are achieved through the two input stages and the output stage, the load network and the feedback inductor are shared, and radio frequency input signals of different frequency bands can be adapted only by switching the load network in the output end and changing impedance; the radio frequency front-end circuit does not need to be switched through an external switch, so that the cost and the size of the radio frequency front-end circuit of the multimode multi-frequency receiver are reduced, and the receiving sensitivity is improved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency technology applications, and in particular to a highly integrated low-noise amplifier circuit that supports dual-mode dual-frequency applications. Background Technology

[0002] Low-noise amplifiers (LNAs) are widely used in receiver RF front-end circuits to receive weak RF signals from antennas, providing sufficiently high power gain to reduce noise contribution throughout the receiver link and improve system reception sensitivity. With the increasing demands of satellite positioning, satellite communication, and broadband wireless communication systems, receiver systems have evolved from single-frequency, narrowband receivers to multi-mode, multi-frequency receivers. The RF front-end of a multi-mode, multi-frequency receiver consists of an antenna, filters, switches, and LNAs.

[0003] Since multi-mode multi-frequency receivers typically employ a multi-antenna design in their RF front-end, multiple low-noise amplifiers or broadband low-noise amplifiers are required for adaptation, resulting in high costs and the introduction of power gain loss, which affects the system's receiving sensitivity. Summary of the Invention

[0004] This invention provides a highly integrated low-noise amplifier circuit that supports dual-mode dual-frequency applications, in order to solve the technical problems of high cost and low sensitivity of existing multi-mode multi-frequency receiver RF front-ends.

[0005] This invention provides a highly integrated low-noise amplifier circuit supporting dual-mode dual-band applications. The circuit includes: a first input stage for receiving a first frequency band radio frequency signal; a second input stage for receiving a second frequency band radio frequency signal; and an output stage connected to the first input stage and the second input stage respectively. The first input stage and the second input stage share a feedback inductor and a load network of the output stage to achieve impedance matching.

[0006] In one embodiment of the present invention, the first input stage, the second input stage, and the output stage constitute a common-source cascode amplifier circuit structure, wherein the first input stage and the second input stage serve as the common source of the common-source cascode amplifier circuit structure; and the output stage serves as the common gate of the common-source cascode amplifier circuit structure.

[0007] In one embodiment of the present invention, the output stage achieves impedance matching of radio frequency signals of different frequency bands by switching the load network to change the impedance.

[0008] In one embodiment of the present invention, the first input stage includes a first transistor, a first resistor, a first capacitor, and a first inductor; wherein, the source of the first transistor is grounded through the feedback inductor, the drain is connected to the input terminal of the output stage, and the gate is connected to one end of the first resistor and one end of the first capacitor respectively; the other end of the first resistor is connected to a first bias voltage; and the other end of the first capacitor is connected to the first frequency band radio frequency signal through the first inductor.

[0009] In one embodiment of the present invention, the second input stage includes a second transistor, a second resistor, a second capacitor, and a second inductor; wherein, the source of the second transistor is grounded through the feedback inductor, the drain is connected to the input terminal of the output stage, and the gate is connected to one end of the second resistor and one end of the second capacitor respectively; the other end of the second resistor is connected to a second bias voltage; and the other end of the second capacitor is connected to the second frequency band radio frequency signal through the second inductor.

[0010] In one embodiment of the present invention, the output stage includes a third transistor, a fourth transistor, a third capacitor, a fourth capacitor, and a fourth inductor; wherein, the source of the third transistor serves as the input terminal of the output stage, and is connected to the output terminals of the first input stage and the second input stage respectively; the gate of the third transistor is connected to a third bias voltage, and the drain is connected to one end of the fourth inductor, one end of the third capacitor, and one end of the fourth capacitor respectively; the other end of the fourth inductor is connected to a power supply voltage; the other end of the third capacitor is connected to the source of the fourth transistor; the other end of the fourth capacitor serves as the output terminal of the output stage; the gate of the fourth transistor is connected to a control signal, and the source is connected to the power supply voltage.

[0011] The beneficial effects of this invention are as follows: The highly integrated low-noise amplifier circuit proposed in this invention supports dual-mode dual-frequency applications. It achieves dual-ended input and single-ended output through two input stages and one output stage, and shares a load network and feedback inductor. It can adapt to different frequency band RF input signals by simply switching the load network inside the output terminal to change the impedance. It does not require external switching, which reduces the cost and size of the RF front-end circuit of the multi-mode multi-frequency receiver and improves the receiving sensitivity. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0013] In the attached diagram:

[0014] Figure 1 A schematic diagram of the existing radio frequency front-end circuit structure of a multimode multi-frequency receiver;

[0015] Figure 2 This is a schematic diagram of a highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications provided in an embodiment of the present invention.

[0016] Figure 3 This is a simulation diagram of the power gain obtained by a low-noise amplifier with dual-frequency application of shared load and feedback in one embodiment of the present invention;

[0017] Figure 4 This is a simulation diagram of the noise figure obtained by a low-noise amplifier with dual-frequency application of shared load and feedback in one embodiment of the present invention;

[0018] Figure 5 This is a simulation diagram of the reflection coefficients of the output ports RF1 and RF2 obtained by a low-noise amplifier with dual-frequency application sharing load and feedback in one embodiment of the present invention. Detailed Implementation

[0019] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0021] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0022] The inventors discovered through research that the RF front-end of currently widely used multimode multifrequency receivers, such as Figure 1As shown, due to the multi-antenna design, multiple dedicated low-noise amplifiers or broadband low-noise amplifiers are required for adaptation. The disadvantages of the traditional solution are: 1) Using multiple dedicated low-noise amplifiers increases the cost and size of the hardware, which is not conducive to the development trend of low cost and miniaturization of receiver front-end circuits; 2) Using broadband low-noise amplifiers requires the addition of switches to achieve frequency band selection, which also increases the cost and size of the hardware. In addition, the switches introduce power gain loss, which reduces the overall gain of the RF front-end circuit, thereby affecting the system's receiving sensitivity.

[0023] Based on the problems existing in the prior art, the present invention proposes a highly integrated low-noise amplifier circuit that supports dual-mode dual-frequency applications. The technical solution of the present invention will be described in detail below with reference to specific implementation.

[0024] Please see Figure 2 , Figure 2 This is a schematic diagram of a highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to an embodiment of the present invention, as shown below. Figure 2 As shown, the circuit includes: a first input stage for receiving a first frequency band radio frequency signal; a second input stage for receiving a second frequency band radio frequency signal; and an output stage connected to the first input stage and the second input stage respectively; wherein the first input stage and the second input stage share a feedback inductor and the load network of the output stage to achieve impedance matching. The circuit of this invention has two radio frequency input terminals and one radio frequency output terminal, arranged sequentially as a first input stage, a second input stage, and an output stage according to the radio frequency signal link transmission path.

[0025] In one embodiment, a first input stage, a second input stage, and an output stage constitute a common-source cascode amplifier circuit structure, wherein the first input stage and the second input stage serve as the common source of the common-source cascode amplifier circuit structure; and the output stage serves as the common gate of the common-source cascode amplifier circuit structure. Specifically, the first input stage consists of a first inductor L1, a first capacitor C1, a first transistor M1, and a first resistor R1, forming the common-source stage circuit structure of the common-source cascode amplifier circuit structure. L1 and C1 form an input impedance matching network, M1 is a common-gate stage amplifying transistor that amplifies the RF power signal (i.e., the first frequency band RF signal) at the RF1 port and converts the voltage signal into a current signal, L3 is a common-source stage feedback inductor, and R1 is a bias resistor that isolates the AC signal from the DC bias voltage (i.e., the first bias voltage VB1). By selecting appropriate inductance values ​​for L1 and L2, capacitance value for C1, and aspect ratio of M1, 50-ohm impedance matching at the RF1 RF input port can be achieved, providing sufficiently high power gain.

[0026] The second input stage consists of a second inductor L2, a second capacitor C2, a second transistor M2, and a second resistor R2, forming the common-source stage circuit structure of a common-source cascode amplifier circuit. L2 and C2 form the input impedance matching network, M2 is the common-gate amplifier transistor that amplifies the RF power signal (i.e., the second frequency band RF signal) at the RF2 port and converts the voltage signal into a current signal. L3 is the common-source feedback inductor, and R2 is the bias resistor that isolates the AC signal from the DC bias voltage (i.e., the second bias voltage VB2). By selecting appropriate inductance values ​​for L2 and L3, capacitance value for C2, and aspect ratio of M2, 50-ohm impedance matching at the RF2 input port can be achieved, providing sufficiently high power gain.

[0027] In one embodiment, the output stage achieves impedance matching for different frequency bands of radio frequency signals by switching the load network to change the impedance. The output stage consists of a third transistor M3, a fourth inductor L4, a third capacitor C3, a fourth capacitor C4, and a fourth transistor M4. Under an appropriate third bias voltage VB3, M3, L4, C3, and C4 constitute the common-gate circuit structure of a common-source common-gate amplifier, and L4, C3, and C4 form the load resonant network (i.e., load network) of transistor M3. Matching for different frequency bands is achieved by switching transistor M4 on and off. When transistor M4 is off, the load network consists of L4 and C4. Selecting appropriate values ​​can achieve good impedance matching in frequency band 1 (i.e., the first frequency band), maximizing gain within the frequency band 1 range, while simultaneously reducing the gain in frequency band 2 (i.e., the second frequency band), providing additional frequency selectivity. When transistor M4 is turned on, the load network consists of L4, C3, and C4. Choosing appropriate values ​​can achieve good impedance matching in frequency band 2, maximize the gain within the frequency band 2 range, and at the same time reduce the gain in frequency band 1, providing additional frequency selectivity.

[0028] Figure 3 This is a simulation diagram of the power gain of a low-noise amplifier using a shared load and feedback in a dual-band application according to one embodiment of the present invention. The RF1 port frequency (band 1) is designed to be 1.55GHz, and the RF2 port frequency (band 2) is designed to be 2.5GHz. It can be seen that the power gain of the RF3 port in the 1.55GHz band is 18.2dB, exhibiting excellent power gain characteristics, while also providing greater than 15dB suppression of 2.5GHz. The power gain of the RF3 port in the 2.5GHz band is 17.1dB, also exhibiting excellent power gain characteristics, while also providing greater than 10dB suppression of 1.55GHz.

[0029] Figure 4This is a simulation diagram of the noise figure of a low-noise amplifier using a shared load and feedback in a dual-band application according to an embodiment of the present invention. The RF1 port frequency (band 1) is designed to be 1.55GHz, and the RF2 port frequency (band 2) is designed to be 2.5GHz. It can be seen that the noise figure of the RF3 port is 1.25dB in the 1.55GHz band and 0.75dB in the 2.5GHz band, exhibiting excellent noise figure characteristics.

[0030] Figure 5 This is a simulation diagram of the reflection coefficients of the output ports RF1 and RF2 of a low-noise amplifier with dual-band application sharing load and feedback in one embodiment of the present invention. The frequency of port RF1 (band 1) is designed to be 1.55GHz, and the frequency of port RF2 (band 2) is designed to be 2.5GHz. It can be seen that the reflection coefficient of port RF1 in the 1.55GHz band is -21dB, and the reflection coefficient of port RF2 in the 2.5GHz band is -24dB, which have excellent port reflection coefficient characteristics and achieve good output impedance matching.

[0031] Based on the above technical solution of the present invention, dual-frequency applications are supported, eliminating the need for additional switching devices to select frequency bands, thus reducing system cost and size; the first input stage, the second input stage, and the output stage adopt a common-source common-gate amplifier structure with multiplexed current, which does not increase additional power consumption; the shared feedback inductor and load network reduce the size of the chip; and the switch-selective load resonant network achieves good impedance matching, maximum gain, and frequency selectivity for frequency bands 1 and 2 respectively.

[0032] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications, characterized in that, The circuit includes: The first input stage is used to receive radio frequency signals in the first frequency band. The second input stage is used to receive radio frequency signals in the second frequency band. An output stage, which is connected to the first input stage and the second input stage respectively; The first input stage and the second input stage share a feedback inductor and the load network of the output stage to achieve impedance matching.

2. The highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to claim 1, characterized in that, The first input stage, the second input stage, and the output stage constitute a common-source cascode amplifier circuit structure, wherein the first input stage and the second input stage serve as the common source of the common-source cascode amplifier circuit structure; and the output stage serves as the common gate of the common-source cascode amplifier circuit structure.

3. The highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to claim 1, characterized in that, The output stage achieves impedance matching for different frequency band radio frequency signals by switching the load network to change the impedance.

4. The highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to claim 1, characterized in that, The first input stage includes a first transistor, a first resistor, a first capacitor, and a first inductor; wherein, the source of the first transistor is grounded through the feedback inductor, the drain is connected to the input terminal of the output stage, and the gate is connected to one end of the first resistor and one end of the first capacitor respectively; the other end of the first resistor is connected to a first bias voltage; and the other end of the first capacitor is connected to the first frequency band radio frequency signal through the first inductor.

5. The highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to claim 1, characterized in that, The second input stage includes a second transistor, a second resistor, a second capacitor, and a second inductor; wherein, the source of the second transistor is grounded through the feedback inductor, the drain is connected to the input terminal of the output stage, and the gate is connected to one end of the second resistor and one end of the second capacitor respectively; the other end of the second resistor is connected to a second bias voltage; and the other end of the second capacitor is connected to the second frequency band radio frequency signal through the second inductor.

6. The highly integrated, low-noise amplifier circuit supporting dual-mode, dual-frequency applications according to claim 1, characterized in that, The output stage includes a third transistor, a fourth transistor, a third capacitor, a fourth capacitor, and a fourth inductor; wherein, the source of the third transistor serves as the input terminal of the output stage, and is connected to the output terminals of the first input stage and the second input stage respectively; the gate of the third transistor is connected to a third bias voltage, and the drain is connected to one end of the fourth inductor, one end of the third capacitor, and one end of the fourth capacitor respectively; the other end of the fourth inductor is connected to the power supply voltage; the other end of the third capacitor is connected to the source of the fourth transistor; the other end of the fourth capacitor serves as the output terminal of the output stage; the gate of the fourth transistor is connected to a control signal, and the source is connected to the power supply voltage.

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