Low-noise amplifier, radio frequency front-end module and communication equipment

Abstract

The utility model relates to a low noise amplifier, a radio frequency front end module and communication equipment, a power amplification unit is connected with a radio frequency output end and is connected with a radio frequency access end through an input unit, and a bypass unit is connected with the radio frequency output end and is connected with the radio frequency access end through the input unit. And the gain of the low-noise amplifier when the bypass unit is switched on is smaller than that when the bypass unit is switched off. By controlling the on-off of the bypass unit, the gain gear of the low-noise amplifier can be adjusted, the low-noise amplifier is suitable for the gain requirement of a large dynamic range, and the use convenience is improved.

Description

Technical Field

[0001] The present application relates to the field of mobile communication technology, and in particular to a low noise amplifier, a radio frequency front-end module and a communication device. Background Art

[0002] With the advancement of technology and the continuous progress of society, the trend towards miniaturization and higher performance in RF communication equipment is accelerating, placing higher demands on RF front-end design. RF front-end modules combine different components into a single, high-performance chip with concentrated functionality. Traditional RF front-end modules use fixed-gain amplifiers, which cannot meet the varying gain requirements of communication equipment and have the disadvantage of low usability. Utility Model Content

[0003] Based on this, it is necessary to provide a low noise amplifier (LNA), a radio frequency front-end module and a communication device that can improve the convenience of use in order to address the above problems.

[0004] A low noise amplifier, comprising:

[0005] An input unit, connected to a radio frequency access terminal, and receiving a radio frequency input signal through the radio frequency access terminal;

[0006] a power amplifying unit connected to the RF output terminal and connected to the RF access terminal through the input unit, wherein the RF output terminal is used to output a RF output signal;

[0007] A bypass unit is connected to the RF output end and is connected to the RF access end through the input unit; wherein the gain of the low noise amplifier when the bypass unit is turned on is less than the gain when the bypass unit is turned off.

[0008] In one embodiment, the input unit includes an inductor Lg and a capacitor C1, the first end of the inductor Lg is connected to the RF access end, the second end of the inductor Lg is connected to the first end of the capacitor C1, and the second end C1 of the capacitor is connected to the power amplification unit and the bypass unit.

[0009] In one embodiment, the power amplification unit includes a power tube assembly and an output assembly, the power tube assembly is connected to the input unit, the bypass unit and the output assembly, and the output assembly is connected to the bypass unit and the RF output end.

[0010] In one embodiment, the power tube assembly includes a power tube M1, a power tube M2, an inductor LS, and an inductor LD. The control end of the power tube M1 is connected to the input unit and the bypass unit, the first end of the power tube M1 is grounded through the inductor LS, the second end of the power tube M1 is connected to the first end of the power tube M2, the second end of the power tube M2 is connected to the output assembly, and is connected to the external power supply end through the inductor LD.

[0011] In one embodiment, the power tube assembly further includes a power supply VB, a power supply VCG, a resistor R1 and a resistor R2, the positive electrode of the power supply VB is connected to the control end of the power tube M1 through the resistor R1, the negative electrode of the power supply VB is grounded, the positive electrode of the power supply VCG is connected to the control end of the power tube M2 through the resistor R2, and the negative electrode of the power supply VCG is grounded.

[0012] In one embodiment, the power tube M1 and the power tube M2 are both MOS tubes.

[0013] In one embodiment, the output component includes a capacitor C4 and a switch SW3, a first end of the capacitor C4 is connected to the power tube component, a second end of the capacitor C4 is connected to the first end of the switch SW3, and a second end of the switch SW3 is connected to the bypass unit and the RF output end.

[0014] In one embodiment, the bypass unit includes a capacitor C2, a capacitor C3, a resistor R3, a switch SW1 and a switch SW2, the first end of the switch SW1 is connected to the input unit and the power amplification unit, the second end of the switch SW1 is connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the first end of the capacitor C3 and is grounded through the resistor R3, the second end of the capacitor C3 is connected to the first end of the switch SW2, and the second end of the switch SW2 is connected to the RF output end and the power amplification unit.

[0015] A radio frequency front-end module comprises a matching circuit, a filter and the above-mentioned low-noise amplifier, wherein the low-noise amplifier is connected to a corresponding filter via a corresponding radio frequency access terminal, and the filter is connected to a corresponding matching circuit.

[0016] A communication device comprises a radio frequency antenna and the above-mentioned radio frequency front-end module.

[0017] In the aforementioned low-noise amplifier, RF front-end module, and communication equipment, the power amplifier unit is connected to the RF output terminal and connected to the RF access terminal via the input unit, and the bypass unit is connected to the RF output terminal and connected to the RF access terminal via the input unit. The gain of the low-noise amplifier when the bypass unit is on is lower than the gain when the bypass unit is off. By controlling the on and off of the bypass unit, the gain level of the low-noise amplifier can be adjusted, which is suitable for gain requirements with a wide dynamic range and improves ease of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a structural block diagram of a low noise amplifier in one embodiment;

[0019] Figure 2 FIG. 4 is a schematic structural diagram of a low noise amplifier in one embodiment. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0022] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0023] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, integers, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integers, operations, components, parts, or combinations thereof.

[0024] In one embodiment, Figure 1As shown, a low noise amplifier is provided, including: an input unit 110, a power amplifying unit 120 and a bypass unit 130, wherein: the input unit 110 is connected to the RF access terminal and receives the RF input signal RFIN through the RF access terminal; the power amplifying unit 120 is connected to the RF output terminal and is connected to the RF access terminal through the input unit 110, and the RF output terminal is used to output the RF output signal RFOUT; the bypass unit 130 is connected to the RF output terminal and is connected to the RF access terminal through the input unit 110; the gain of the low noise amplifier when the bypass unit 130 is turned on is less than the gain when the bypass unit 130 is turned off.

[0025] The specific values ​​of the gain of the low-noise amplifier when the bypass unit 130 is turned on and the gain when the bypass unit 130 is turned off are not unique and can be determined according to actual needs by designing the internal components of the power amplifier unit 120 and the bypass unit 130. It is only necessary to ensure that the gain when the bypass unit 130 is turned on is less than the gain when the bypass unit 130 is turned off. The gain when the bypass unit 130 is turned on can be used as the low-gain gear, and the gain when the bypass unit 130 is turned off can be used as the high-gain gear. According to the actual usage scenario, the power amplifier unit 120 and the bypass unit 130 can be controlled to achieve switching between the low-gain gear and the high-gain gear. When the low-noise amplifier operates in the high-gain gear, the RF input signal RFIN is processed by the input unit 110 and then amplified by the power amplifier unit 120 to obtain the RF output signal RFOUT. When the low-noise amplifier operates in the low-gain gear, the RF input signal RFIN is processed by the input unit 110 and then amplified by the bypass unit 130 to obtain the RF output signal RFOUT. The bypass unit 130 only needs to reduce the gain of the low noise amplifier when it is turned on, and can be implemented with a small number of components, thereby simplifying the structure and reducing the occupied space.

[0026] The function of the input unit 110 is to match the RF input impedance and improve the transmission efficiency of the RF signal. Figure 2 As shown, the input unit 110 includes an inductor Lg and a capacitor C1. The first end of the inductor Lg is connected to the RF access terminal, the second end of the inductor Lg is connected to the first end of the capacitor C1, and the second end of the capacitor C1 is connected to the power amplifier unit 120 and the bypass unit 130. When the low-noise amplifier operates in a high-gain mode, the RF input signal RFIN is transmitted to the power amplifier unit 120 after impedance matching is performed by the inductor Lg and the capacitor C1. When the low-noise amplifier operates in a low-gain mode, the RF input signal RFIN is transmitted to the bypass unit 130 after impedance matching is performed by the inductor Lg and the capacitor C1.

[0027] Furthermore, power amplifier unit 120 may include a power tube assembly 122 and an output assembly 124. Power tube assembly 122 connects input unit 110, bypass unit 130, and output assembly 124. Output assembly 124 connects bypass unit 130 and the RF output terminal. When the low-noise amplifier operates in a high-gain mode, power tube assembly 122 amplifies the signal power and transmits the amplified signal to output assembly 124.

[0028] The specific structures of the power tube assembly 122 and the output assembly 124 are not unique. In one embodiment, the power tube assembly 122 includes a power tube M1, a power tube M2, an inductor LS, and an inductor LD. The control end of the power tube M1 is connected to the input unit 110 and the bypass unit 130, specifically to the second end of the capacitor C1 in the input unit 110. The first end of the power tube M1 is grounded via the inductor LS, and the second end of the power tube M1 is connected to the first end of the power tube M2. The second end of the power tube M2 is connected to the output assembly 124 and is connected to the external power supply terminal VDD via the inductor LD. Specifically, the power tubes M1 and M2 can be MOS tubes, with the gate as the control end, the source as the first end, and the drain as the second end.

[0029] Furthermore, the power transistor assembly 122 may also include a power supply VB, a power supply VCG, a resistor R1, and a resistor R2. The positive electrode of the power supply VB is connected to the control terminal of the power transistor M1 via the resistor R1, the negative electrode of the power supply VB is grounded, the positive electrode of the power supply VCG is connected to the control terminal of the power transistor M2 via the resistor R2, and the negative electrode of the power supply VCG is grounded. Corresponding power supplies and resistors are provided at the control terminals of the power transistors M1 and M2, respectively, to maintain the control terminals of the power transistors M1 and M2 at a high level, thereby ensuring stable operation of the power transistors M1 and M2.

[0030] In one embodiment, the output component 124 includes a capacitor C4 and a switch SW3. The first end of the capacitor C4 is connected to the power tube component 122, specifically to the second end of the power tube M2. The second end of the capacitor C4 is connected to the first end of the switch SW3. The second end of the switch SW3 is connected to the bypass unit 130 and the RF output terminal. The switch SW3 can be a manual switch or a control switch. When the switch SW3 is turned on, the amplified signal output by the power tube component 122 passes through the capacitor C4 and outputs the RF output signal RFOUT through the RF output terminal. The function of the capacitor C4 is to isolate the DC signal at the output terminal and match the output impedance.

[0031] In addition, the specific structure of the bypass unit 130 is not unique. Figure 2The bypass unit 130 may include a capacitor C2, a capacitor C3, a resistor R3, a switch SW1, and a switch SW2. The first end of the switch SW1 is connected to the input unit 110 and the power amplification unit 120, specifically to the second end of the capacitor C1 and the control end of the power tube M1. The second end of the switch SW1 is connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the first end of the capacitor C3, and is grounded through the resistor R3. The second end of the capacitor C3 is connected to the first end of the switch SW2, and the second end of the switch SW2 is connected to the RF output end and the power amplification unit 120, specifically to the second end of the switch SW3. The switches SW1 and SW2 may be manual switches or control switches.

[0032] Specifically, when the low-noise amplifier operates in the high-gain mode, switches SW1 and SW2 are turned off, switch SW3 is turned on, and the power tube assembly 122 performs power amplification on the signal output by the input unit 110. The amplified signal is impedance-matched by capacitor C4 and then outputs the RF output signal RFOUT through the RF output terminal. When the low-noise amplifier operates in the low-gain mode, switch SW3 is turned off, switches SW1 and SW2 are turned on, and the signal output by the input unit 110 is impedance-matched by capacitor C4 and then outputs the RF output signal RFOUT through the RF output terminal. Through the above circuit design, by utilizing the combination of switches and resistor networks, the low-noise amplifier has two operating states, high-gain mode and low-gain mode. The high-gain mode can achieve a high gain of 19dB, and the low-gain mode can achieve a -5dB attenuation, realizing the switching between high-gain and gain-attenuation modes, which is suitable for system applications with a large dynamic range. Capacitor C3 and capacitor C4 are separated by switches SW2 and SW3, avoiding device redundancy caused by capacitors in series and saving layout area.

[0033] By adding switch SW3 to the RF output of the low-noise amplifier, when the low-noise amplifier operates in the low-gain range, only the off-capacitor Coff of switch SW3 is exposed to the load. This has minimal impact on the design and adjustment of the output matching. Furthermore, because switch SW3 is added to the output, it has no effect on the noise figure (NF) in the high-gain range. Furthermore, in the low-gain range (switch SW3 off, switches SW1 and SW2 on), both the input and output matching of the low-noise amplifier remain below -7dB, and are minimally affected by external matching inductors.

[0034] In one embodiment, a radio frequency front-end module is provided, comprising a matching circuit, a filter and the above-mentioned low-noise amplifier, wherein the low-noise amplifier is connected to a corresponding filter via a corresponding radio frequency access terminal, and the filter is connected to a corresponding matching circuit. There may be multiple matching circuits, filters and low-noise amplifiers, and the matching circuit may adopt an LC (inductor-capacitor) matching topology or an L-type dual-inductor matching topology. The filtering frequency band of each filter may be set according to actual needs. Furthermore, the radio frequency front-end module may also include an radio frequency switch, which connects each matching circuit and may also connect to an radio frequency antenna. The radio frequency switch specifically includes a static contact and multiple moving contacts, the static contact is connected to the radio frequency antenna, and each moving contact is connected to a corresponding matching circuit. The radio frequency switch can be controlled to open a single switch so that each frequency band works separately; or the radio frequency switch can be controlled to open multiple switches at the same time so that several frequency bands work simultaneously during carrier aggregation.

[0035] In one embodiment, a communication device is provided, comprising an RF antenna and the aforementioned RF front-end module. Furthermore, the communication device may further comprise a controller connected to the RF switch to control the on / off switching of the RF switch. The controller may be of various types, and may include, for example, a CPU (Central Processing Unit), an MCU (Microcontroller Unit), an FPGA (Field-Programmable Gate Array), or other devices.

[0036] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0037] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A low noise amplifier, characterized in that include: An input unit, connected to a radio frequency access terminal, and receiving a radio frequency input signal through the radio frequency access terminal; a power amplifying unit connected to the RF output terminal and connected to the RF access terminal through the input unit, wherein the RF output terminal is used to output a RF output signal; a bypass unit connected to the RF output terminal and connected to the RF access terminal through the input unit; wherein the gain of the low-noise amplifier when the bypass unit is turned on is less than the gain when the bypass unit is turned off; The bypass unit includes a capacitor C2, a capacitor C3, a resistor R3, a switch SW1 and a switch SW2, wherein a first end of the switch SW1 is connected to the input unit and the power amplification unit, a second end of the switch SW1 is connected to the first end of the capacitor C2, a second end of the capacitor C2 is connected to the first end of the capacitor C3 and is grounded through the resistor R3, a second end of the capacitor C3 is connected to the first end of the switch SW2, and a second end of the switch SW2 is connected to the RF output end and the power amplification unit.

2. The low noise amplifier according to claim 1, wherein The input unit includes an inductor Lg and a capacitor C1, a first end of the inductor Lg is connected to the RF access terminal, a second end of the inductor Lg is connected to the first end of the capacitor C1, and a second end of the capacitor C1 is connected to the power amplification unit and the bypass unit.

3. The low noise amplifier according to claim 1, wherein The power amplification unit includes a power tube component and an output component. The power tube component is connected to the input unit, the bypass unit and the output component. The output component is connected to the bypass unit and the radio frequency output end.

4. The low noise amplifier according to claim 3, wherein: The power tube assembly includes a power tube M1, a power tube M2, an inductor LS and an inductor LD. The control end of the power tube M1 is connected to the input unit and the bypass unit. The first end of the power tube M1 is grounded through the inductor LS. The second end of the power tube M1 is connected to the first end of the power tube M2. The second end of the power tube M2 is connected to the output assembly and connected to the external power supply end through the inductor LD.

5. The low noise amplifier according to claim 4, wherein: The power tube assembly also includes a power supply VB, a power supply VCG, a resistor R1 and a resistor R2. The positive electrode of the power supply VB is connected to the control end of the power tube M1 through the resistor R1, the negative electrode of the power supply VB is grounded, the positive electrode of the power supply VCG is connected to the control end of the power tube M2 through the resistor R2, and the negative electrode of the power supply VCG is grounded.

6. The low noise amplifier according to claim 4, wherein: The power tube M1 and the power tube M2 are both MOS tubes.

7. The low noise amplifier according to claim 3, wherein: The output component includes a capacitor C4 and a switch SW3, a first end of the capacitor C4 is connected to the power tube component, a second end of the capacitor C4 is connected to a first end of the switch SW3, and a second end of the switch SW3 is connected to the bypass unit and the RF output end.

8. The low noise amplifier according to any one of claims 1 to 7, wherein: The switch SW1 is a manual switch or a control switch, and the switch SW2 is a manual switch or a control switch.

9. A radio frequency front-end module, characterized in that: The invention comprises a matching circuit, a filter and a low noise amplifier according to any one of claims 1 to 8, wherein the low noise amplifier is connected to a corresponding filter through a corresponding radio frequency access terminal, and the filter is connected to a corresponding matching circuit.

10. A communication device, characterized in that: It comprises a radio frequency antenna and the radio frequency front-end module as claimed in claim 9.

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