RF front-end module
By adding an isolation circuit to the RF front-end module, the problem of the low-noise amplifier being turned off affecting the receiver bypass channel is solved, ensuring that the receiver can correctly demodulate the RF signal.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- LANSUS TECH INC
- Filing Date
- 2025-07-14
- Publication Date
- 2026-06-30
Smart Images
Figure CN224438991U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wireless communication technology, and in particular to a radio frequency front-end module. Background Technology
[0002] The radio frequency front-end module is a core component of a wireless communication system. Its main responsibility is to amplify small signals and transmit them to the antenna for transmission, or to amplify small signals received by the antenna and transmit them to the subsequent receiving circuit.
[0003] The RF front-end module mainly includes an RF switch, a signal transmission path for transmitting the RF signal amplified by the power amplifier from the signal transmitter, and a signal reception path for transmitting the RF signal received by the antenna. The signal reception path includes a receiver amplification channel that amplifies the RF signal through a low-noise amplifier and a receiver bypass channel that directly outputs the RF signal. The receiver bypass channel and the output of the low-noise amplifier are connected in parallel to output the RF signal from the signal receiver. The receiver bypass channel and the receiver amplification channel of this RF front-end module are switched by a host computer through logic control signals, so that the RF signal received by the receiver bypass channel is directly output from the signal receiver, or the RF signal amplified by the low-noise amplifier is output from the signal receiver.
[0004] In existing technologies, such as Figure 1 As shown, the RF front-end module 100 includes a single-pole double-throw (SPD) switch SW1, a low-noise amplifier (LNA) 1, and a single-pole single-throw (SPS) switch SW2. The common terminal of SPD switch SW1 is used to connect to an antenna. The first connection terminal of SPD switch SW1 is connected to the first connection terminal of the first SPD switch SW2 and the input terminal of the LNA 1. The second connection terminal of SPD switch SW1 is connected to a signal transmitting end. The control terminal of SPD switch SW1 is used to receive a logic control signal to control the common terminal of SPD switch SW1 to connect to a signal transmitting path or to the first connection terminal of the first SPD switch SW2 and the input terminal of the LNA 1. The output terminal of the LNA 1 and the second connection terminal of SPD switch SW2 are connected in parallel to a signal receiving end. The control terminal of the LNA 1 is used to receive a logic control signal to control the LNA 1 to open or close. The control terminal of SPD switch SW2 is used to receive a logic control signal to control the single-pole single-throw (SPS) switch to open or close.
[0005] The common terminal of the single-pole double-throw switch SW1 is set to SW1-3, the first connection terminal of the single-pole double-throw switch SW1 is set to SW1-1, the second connection terminal of the single-pole double-throw switch SW1 is set to SW1-2, the control terminal of the single-pole double-throw switch SW1 is set to SW1-1, the input terminal of the low-noise amplifier LNA1 is set to LNA1-2, the control terminal of the low-noise amplifier LNA1 is set to LNA1-3, the first connection terminal of the single-pole single-throw switch SW2 is set to SW2-1, the second connection terminal of the single-pole single-throw switch SW2 is set to SW2-2, and the control terminal of the single-pole single-throw switch SW2 is set to SW2-3. The working principle of the RF front-end module 100 is as follows: SW1-4 receives a logic control signal to control SW1-3 to connect to SW1-1 or SW1-2. When SW1-2 and SW1-3 are connected, the RF signal in the signal transmission path is transmitted by the antenna. When SW1-1 and SW1-3 are connected, the antenna receives the RF signal. When the RF signal is a low-power signal, LNA1-3 receives a logic control signal to connect LNA1-1 and LNA1-2, that is, to turn on the low-noise amplifier LNA1 to amplify the RF signal before outputting it. At the same time, SW2-3 receives a logic control signal to turn off the single-pole single-throw switch SW2. When the RF signal is a high-power signal, LNA1-3 receives a logic control signal to turn off LNA1-1 and LNA1-2, that is, to turn off the low-noise amplifier LNA1. At the same time, SW2-3 receives a logic control signal to connect SW2-1 and SW2-2, thereby directly outputting the RF signal from the signal receiving end to the external receiver.
[0006] In the aforementioned RF front-end module 100, when the signal passes through the receiver bypass channel, although the low-noise amplifier LNA1 is in the off state, since the output of the receiver amplifier channel and the output of the receiver bypass channel are connected in parallel, the low-noise amplifier LNA1 will affect the RF signal of the receiver bypass channel, causing the RF signal quality of the receiver bypass channel to degrade. This will result in the receiver being unable to correctly demodulate the RF signal input from the bypass channel after the RF signal is output to the receiver. Utility Model Content
[0007] To address the shortcomings of the existing technology, this utility model proposes a new radio frequency front-end module to solve the problem that the quality of the radio frequency signal output from the bypass channel in the existing radio frequency front-end module degrades due to the influence of the low-noise amplifier in the off state, thus causing the receiver to be unable to properly demodulate the radio frequency signal input from the bypass channel.
[0008] To address the aforementioned technical problems, this utility model provides a radio frequency front-end module, which includes a switching switch, a signal transmission path, and a signal reception path; the switching switch connects the signal transmission path and the signal reception path to an antenna respectively, and is used to switch the signal transmission path to be connected to the antenna, or to switch the signal reception path to be connected to the antenna; the signal reception path includes a low-noise amplifier, a signal receiving end, a first single-pole single-throw switch, and an isolation circuit;
[0009] The common terminal of the switching switch is used to connect to the antenna, and the input terminal of the switching switch is used to receive a first logic control signal. According to the received first logic control signal, the common terminal of the switching switch is controlled to connect to the signal transmission path, or to the first input terminal of the low noise amplifier, or / and connected to the first connection terminal of the first single-pole single-throw switch.
[0010] The signal transmission path is used to transmit a first radio frequency signal;
[0011] The control terminal of the low-noise amplifier is used to receive a second logic control signal and to control the low-noise amplifier to turn on or off according to the received second logic control signal.
[0012] The signal receiving end is used to receive the second radio frequency signal;
[0013] The control terminal of the first single-pole single-throw switch is used to receive a third logic control signal and to control the opening or closing of the first single-pole single-throw switch according to the received third logic control signal.
[0014] The first input terminal of the isolation circuit is connected to the output terminal of the low-noise amplifier, the second input terminal of the isolation circuit is connected to the second connection terminal of the first single-pole single-throw switch, and the output terminal of the isolation circuit is connected to the signal receiving terminal. The isolation circuit is used to isolate the radio frequency signal between the output terminal of the low-noise amplifier and the output terminal of the first single-pole single-throw switch.
[0015] Preferably, the switching switch is a first single-pole double-throw switch; the common terminal of the first single-pole double-throw switch serves as the common terminal of the switching switch, the first connection terminal of the first single-pole double-throw switch is connected to the first input terminal of the low-noise amplifier and the first connection terminal of the first single-pole double-throw switch respectively, the second connection terminal of the first single-pole double-throw switch is connected to the signal transmission path, and the control terminal of the first single-pole double-throw switch serves as the input terminal of the switching switch, and is used to control the common terminal of the first single-pole double-throw switch to connect to the first connection terminal or the second connection terminal of the first single-pole double-throw switch according to the first logic control signal.
[0016] Preferably, the switching switch is a single-pole triple-throw switch; the common terminal of the single-pole triple-throw switch serves as the common terminal of the switching switch, the first connection terminal of the single-pole triple-throw switch is connected to the first connection terminal of the first single-pole single-throw switch, the second connection terminal of the single-pole triple-throw switch is connected to the signal transmission path, the third connection terminal of the single-pole triple-throw switch is connected to the first input terminal of the low-noise amplifier, and the first control terminal and the second control terminal of the single-pole triple-throw switch together serve as the input terminal of the switching switch, and are used to control the common terminal of the single-pole triple-throw switch to connect to one of the first connection terminal, the second connection terminal and the third connection terminal of the single-pole triple-throw switch according to the first logic control signal.
[0017] Preferably, the isolation circuit includes a first resistor; the first end of the first resistor serves as the first input terminal of the isolation circuit, and the second end of the first resistor serves as both the second input terminal and the output terminal of the isolation circuit.
[0018] Preferably, the isolation circuit further includes a second resistor and a third resistor;
[0019] The first terminal of the second resistor is connected to the first terminal of the first resistor;
[0020] The first end of the third resistor is connected to the second end of the first resistor, and the second end of the third resistor is connected to the second end of the second resistor and then grounded.
[0021] Preferably, the isolation circuit includes a fourth resistor, a fifth resistor, and a sixth resistor;
[0022] The first terminal of the fourth resistor serves as the first input terminal of the isolation circuit.
[0023] The first end of the fifth resistor is connected to the second end of the fourth resistor, and the second end of the fifth resistor serves as both the second input end and the output end of the isolation circuit.
[0024] The first end of the sixth resistor is connected to the second end of the fourth resistor, and the second end of the sixth resistor is grounded.
[0025] Preferably, the isolation circuit includes a second single-pole single-throw switch; the first connection terminal of the second single-pole single-throw switch is connected to the output terminal of the low-noise amplifier, the second connection terminal of the second single-pole single-throw switch is connected to the first input terminal of the isolation circuit, and the control terminal of the second single-pole single-throw switch is used to receive a fourth logic control signal and to control the opening or closing of the second single-pole single-throw switch according to the received fourth logic control signal.
[0026] Preferably, the second single-pole single-throw switch and the first single-pole single-throw switch are combined to form a second single-pole double-throw switch;
[0027] The first connection terminal of the second single-pole double-throw switch serves as both the first connection terminal of the second single-pole double-throw switch and the first input terminal of the isolation circuit. The second connection terminal of the second single-pole double-throw switch serves as both the first connection terminal of the first single-pole double-throw switch and the second input terminal of the isolation circuit. The common terminal of the second single-pole double-throw switch serves as both the second connection terminal of the first single-pole double-throw switch and the output terminal of the isolation circuit. The control terminal of the second single-pole double-throw switch serves as both the control terminal of the first single-pole double-throw switch and the control terminal of the second single-pole double-throw switch, and is used to receive a fifth logic control signal. Simultaneously, based on the received fifth logic control signal, the common terminal of the second single-pole double-throw switch is connected to either the first connection terminal or the second connection terminal of the second single-pole double-throw switch.
[0028] Preferably, the isolation circuit includes a circulator; the reflecting end of the circulator serves as the first input end of the isolation circuit, the output end of the circulator serves as the second input end of the isolation circuit, and the input end of the circulator serves as the output end of the isolation circuit.
[0029] Compared with the prior art, the radio frequency front-end module of this utility model adds an isolation circuit between the output terminal of the low noise amplifier and the second connection terminal of the first single-pole single-throw switch. This isolation circuit isolates the radio frequency signal between the output terminal of the low noise amplifier and the second connection terminal of the first single-pole single-throw switch, thereby reducing the influence of the low noise amplifier in the off state on the radio frequency signal of the receiving bypass channel where the first single-pole single-throw switch is located, so that the external receiver can correctly demodulate the received radio frequency signal. Attached Figure Description
[0030] The present invention will now be described in detail with reference to the accompanying drawings. The above and other aspects of the present invention will become clearer and easier to understand through the detailed description in conjunction with the following drawings. In the drawings:
[0031] Figure 1 Circuit schematic diagram of an existing RF front-end module;
[0032] Figure 2 The circuit schematic diagram of the first radio frequency front-end module provided in Embodiment 1 of this utility model;
[0033] Figure 3 This is a circuit schematic diagram of the second type of radio frequency front-end module provided in Embodiment 2 of this utility model;
[0034] Figure 4 The circuit schematic diagram of the radio frequency front-end module provided in Embodiment 3 of this utility model;
[0035] Figure 5 The circuit schematic diagram of the radio frequency front-end module provided in Embodiment 4 of this utility model;
[0036] Figure 6 The circuit schematic diagram of the radio frequency front-end module provided in Embodiment 5 of this utility model;
[0037] Figure 7 The circuit diagram of the radio frequency front-end module provided in Embodiment Six of this utility model. Detailed Implementation
[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.
[0039] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0040] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0041] Example 1
[0042] This utility model embodiment provides a radio frequency front-end module 200, such as Figure 2As shown, it includes a switching switch 201, a signal transmission path, and a signal reception path; the switching switch 201 connects the signal transmission path and the signal reception path to the antenna ANT respectively, and is used to switch the signal transmission path to be connected to the antenna ANT, or to switch the signal reception path to be connected to the antenna ANT; the signal reception path includes a low noise amplifier LNA, a signal receiver RXOut, a first single-pole single-throw switch SW4, and an isolation circuit 202.
[0043] The antenna (ANT) is used to transmit or receive radio frequency signals.
[0044] The common terminal of the switch 201 is used to connect to the antenna ANT, and the input terminal of the switch 201 is used to receive the first logic control signal. According to the received first logic control signal, the common terminal of the switch 201 is controlled to connect to the signal transmission path TXIn, or to the first input terminal of the low noise amplifier LNA, or / and to the first connection terminal of the first single-pole single-throw switch SW4.
[0045] In this embodiment, the switching switch 201 is a first single-pole double-throw switch SW3; the common terminal of the first single-pole double-throw switch SW3 serves as the common terminal of the switching switch 201; the first connection terminal of the first single-pole double-throw switch SW3 is connected to the first input terminal of the low-noise amplifier LNA and the first connection terminal of the first single-pole double-throw switch SW4, respectively; the second connection terminal of the first single-pole double-throw switch SW3 is connected to the signal transmission path TXIn; the control terminal of the first single-pole double-throw switch SW3 serves as the input terminal of the switching switch 201, and is used to control the common terminal of the first single-pole double-throw switch SW3 to connect to the first connection terminal or the second connection terminal of the first single-pole double-throw switch SW3 according to the first logic control signal.
[0046] The signal transmission path TXIn is used to transmit the first radio frequency signal through its signal transmission terminal TXIn.
[0047] The control terminal of the low-noise amplifier (LNA) is used to receive a second logic control signal and to control the LNA to turn on or off according to the received second logic control signal.
[0048] The signal receiver RXOut is used to receive the second radio frequency signal.
[0049] The control terminal of the first single-pole single-throw switch SW4 is used to receive a third logic control signal and to control the opening or closing of the first single-pole single-throw switch SW4 according to the received third logic control signal.
[0050] The first input terminal of the isolation circuit 202 is connected to the output terminal of the low noise amplifier LNA, the second input terminal of the isolation circuit 202 is connected to the second connection terminal of the first single-pole single-throw switch SW4, and the output terminal of the isolation circuit 202 is connected to the signal receiving terminal RXOut. The isolation circuit 202 is used to isolate the radio frequency signal between the output terminal of the low noise amplifier LNA and the output terminal of the first single-pole single-throw switch SW4.
[0051] The isolation circuit 202 includes a first resistor R1; the first end of the first resistor R1 serves as the first input terminal of the isolation circuit 202, and the second end of the first resistor R1 serves as both the second input terminal and the output terminal of the isolation circuit 202. The resistance value of the first resistor R1 is several tens of ohms.
[0052] The first, second, and third logic control signals mentioned above are all sent out by an external host computer.
[0053] The common terminal of the first single-pole double-throw switch SW3 is set as SW3-3, the first connection terminal of the first single-pole double-throw switch SW3 is set as SW3-1, the second connection terminal of the first single-pole double-throw switch SW3 is set as SW3-2, the first input terminal of the low-noise amplifier LNA is set as LNA-1, the control terminal of the low-noise amplifier LNA is set as LNA-3, the output terminal of the low-noise amplifier LNA is set as LNA-2, the first connection terminal of the first single-pole single-throw switch SW4 is set as SW4-1, and the second connection terminal of the first single-pole single-throw switch SW4 is set as SW4-1.
[0054] When the RF front-end module 200 is in the transmitting state, SW3-2 and SW-3 are connected, and the RF signal transmitted by the signal transmission path TXIn is emitted by the antenna ANT through its signal transmission terminal TXIn.
[0055] When the RF front-end module 200 is in receiving mode, SW3-3 and SW3-1 are connected, and the RF signal received by the antenna ANT enters the signal receiving path. If the RF signal received by the antenna ANT is a low-power signal, LNA-3 controls the low-noise amplifier LNA to turn on through the received second logic control signal, that is, LNA-1 and LNA-2 are connected. The low-noise amplifier LNA amplifies the low-power signal and outputs it through the signal receiving terminal RXOut. Since the low-noise amplifier LNA has a large gain, the first resistor R1 will not have a significant impact on the RF signal in the receiving amplification channel where the low-noise amplifier LNA is located. If the RF signal received by the antenna ANT is a high-power signal, LNA-3 controls the low-noise amplifier LNA to turn off through the received second logic control signal, that is, LNA-1 and LNA-2 are cut off, and the low-noise amplifier LNA does not work. The third logic control signal received by SW4-3 controls the first single-pole single-throw switch SW4 to turn on, that is, SW4-1 and SW4-2 are connected. The high-power signal is then directly output through the signal receiving terminal RXOut after passing through the first single-pole single-throw switch SW4. Since the first resistor R1 can act as an isolation element, the influence of the low-noise amplifier LNA in the off state on the radio frequency signal of the receiver bypass channel where the first single-pole single-throw switch SW4 is located can be reduced.
[0056] Compared with the prior art, the RF front-end module 200 of this utility model adds an isolation circuit 202 between the output terminal of the low noise amplifier LNA and the second connection terminal of the first single-pole single-throw switch SW4. In this way, the RF signal between the output terminal of the low noise amplifier LNA and the second connection terminal of the first single-pole single-throw switch SW4 can be isolated by the isolation circuit 202, thereby reducing the influence of the low noise amplifier LNA in the off state on the RF signal of the receiving bypass channel where the first single-pole single-throw switch SW4 is located, so that the external receiver can correctly demodulate the received RF signal.
[0057] Example 2
[0058] The RF front-end module 300 in this embodiment differs from the RF front-end module 200 in Embodiment 1 in that, for example... Figure 3 As shown, the isolation circuit 3202 also includes a second resistor R2 and a third resistor R3.
[0059] The first end of the second resistor R2 is connected to the first end of the first resistor R1.
[0060] The first end of the third resistor R3 is connected to the second end of the first resistor R1, and the second end of the third resistor R3 is connected to the second end of the second resistor R2 and then grounded.
[0061] At this time, the first resistor R1, the second resistor R2, and the third resistor R3 form a PI-type attenuator with an attenuation of several dB. If the RF signal received by the antenna ANT is a low-power signal, the low-power signal passes through the low-noise amplifier LNA and the PI-type attenuator to reach the signal receiving end RXOut. Since the low-noise amplifier LNA has a large gain, the PI-type attenuator will not have a significant impact on the RF signal in the receiving amplification channel where the low-noise amplifier LNA is located. At this time, the first single-pole single-throw switch SW4 is in the off state. If the RF signal received by the antenna ANT is a high-power signal, the low-noise amplifier LNA is not working, and the first single-pole single-throw switch SW4 is conducting. The high-power signal passes through the first single-pole single-throw switch SW4 to reach the signal receiving end RXOut. The PI-type attenuator can also play an isolation role to reduce the impact of the low-noise amplifier LNA in the off state on the RF signal in the receiving bypass channel where the first single-pole single-throw switch SW4 is located.
[0062] Example 3
[0063] The RF front-end module 400 in this embodiment differs from the RF front-end module 300 in Embodiment 2 in that, for example... Figure 4 As shown, the isolation circuit 4202 includes a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6.
[0064] Among them, the first end of the fourth resistor R4 serves as the first input terminal of the isolation circuit 4202.
[0065] The first end of the fifth resistor R5 is connected to the second end of the fourth resistor R4. The second end of the fifth resistor R5 serves as the second input terminal and the output terminal of the isolation circuit 4202, respectively.
[0066] The first end of the sixth resistor R6 is connected to the second end of the fourth resistor R4, and the second end of the sixth resistor R6 is grounded.
[0067] The fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 form a T-type attenuator, which has the same function as the PI-type attenuator in Example 1, and will not be described in detail here.
[0068] Example 4
[0069] The RF front-end module 500 in this embodiment differs from the RF front-end module 200 in Embodiment 1 in that the isolation circuit 5202 includes a second single-pole single-throw switch. The first connection terminal of the second single-pole single-throw switch is connected to the output terminal of the low-noise amplifier (LNA), and the second connection terminal of the second single-pole single-throw switch is connected to the first input terminal of the isolation circuit 5202. The control terminal of the second single-pole single-throw switch is used to receive a fourth logic control signal and to control the opening or closing of the second single-pole single-throw switch according to the received fourth logic control signal.
[0070] like Figure 5 As shown, the second single-pole single-throw switch and the first single-pole single-throw switch are combined to form the second single-pole double-throw switch SW5.
[0071] The first connection terminal of the second single-pole double-throw switch SW5 serves as both the first connection terminal of the second single-pole single-throw switch and the first input terminal of the isolation circuit 5202. The second connection terminal of the second single-pole double-throw switch SW5 serves as both the first connection terminal of the first single-pole single-throw switch and the second input terminal of the isolation circuit 5202. The common terminal of the second single-pole double-throw switch SW5 serves as both the second connection terminal of the first single-pole single-throw switch and the second connection terminal of the isolation circuit 5202. The control terminal of the second single-pole double-throw switch SW5 serves as both the control terminal of the first single-pole single-throw switch and the control terminal of the second single-pole single-throw switch, and is used to receive the fifth logic control signal. Simultaneously, based on the received fifth logic control signal, the common terminal of the second single-pole double-throw switch SW5 is connected to either the first connection terminal or the second connection terminal of the second single-pole double-throw switch SW5.
[0072] This is equivalent to the second connection terminal of the second single-pole single-throw switch and the second connection terminal of the first single-pole single-throw switch serving as the same connection terminal.
[0073] The first connection terminal of the second single-pole double-throw switch SW5 is set as SW5-1, the second connection terminal of the second single-pole double-throw switch SW5 is set as SW5-2, the common terminal of the second single-pole double-throw switch SW5 is set as SW5-3, and the control terminal of the second single-pole double-throw switch SW5 is set as SW5-4.
[0074] When the RF signal received by the antenna ANT is a low-power signal, the low-noise amplifier (LNA) is turned on. The low-power signal is amplified by the LNA and reaches SW5-1. At this time, SW5-4 controls SW5-1 and SW5-3 to connect according to the received fifth logic control signal. The amplified signal then reaches the signal receiver RXOut through the common terminal of the second single-pole single-throw switch. When the RF signal received by the antenna ANT is a high-power signal, the LNA is turned off. The high-power signal directly reaches SW5-2. At this time, SW5-4 controls SW5-2 and SW5-3 to connect according to the received fourth logic control signal. The high-power signal then reaches the signal receiver RXOut through the second single-pole single-throw switch. Since only one channel is connected between the receiving amplification channel where the LNA is located and the receiving bypass channel where the first single-pole single-throw switch is located, the LNA in the off state does not affect the RF signal of the receiving bypass channel. This is equivalent to the second single-pole double-throw switch SW5 acting as an isolation device.
[0075] Example 5
[0076] The RF front-end module 600 in this embodiment differs from the RF front-end module 200 in Embodiment 1 in that, for example... Figure 6 As shown, the isolation circuit 6202 is a circulator L1; the reflecting end of the circulator L1 serves as the first input terminal of the isolation circuit 6202, the output terminal of the circulator L1 serves as the second input terminal of the isolation circuit 6202, and the input terminal of the circulator L1 serves as the output terminal of the isolation circuit 6202. The signal transmission direction of the circulator L1 is from its input terminal - reflecting end - output terminal, that is, from the output terminal of the isolation circuit 6202 - the first input terminal of the isolation circuit 6202 - the second input terminal of the isolation circuit 6202.
[0077] The transmitter of circulator L1 is set to L1-2, the input of circulator L1 is set to L1-1, and the output of circulator L1 is set to L1-3.
[0078] When the first single-pole single-throw switch is off and the low-noise amplifier (LNA) is on, the RF signal output from the LNA passes through L1-2, L1-3, and L1-1 sequentially before reaching the signal receiver RXOut. When the first single-pole single-throw switch is on and the LNA is off, the RF signal output from the second connection terminal of the first single-pole single-throw switch passes through L1-3 and L1-1 sequentially before reaching the signal receiver RXOut. At this time, since the circulator L1 is directional, the off-state LNA will not affect the RF signal of the bypass channel, which is equivalent to the circulator L1 playing an isolation role.
[0079] Example 6
[0080] The RF front-end module 700 in this embodiment differs from the RF front-end module 600 in embodiment five in that, for example... Figure 7 As shown, the switching switch 7201 includes a single-pole triple-throw switch SW6; the common terminal of the single-pole triple-throw switch SW6 serves as the common terminal of the switching switch 7201; the first connection terminal of the single-pole triple-throw switch SW6 is connected to the first connection terminal of the first single-pole single-throw switch SW4; the second connection terminal of the single-pole triple-throw switch SW6 is connected to the signal transmission path; the third connection terminal of the single-pole triple-throw switch SW6 is connected to the first input terminal of the low-noise amplifier LNA; the first control terminal and the second control terminal of the single-pole triple-throw switch SW6 together serve as the input terminal of the switching switch 7201, and are used to control the common terminal of the single-pole triple-throw switch SW6 to connect to one of the first connection terminal, the second connection terminal, and the third connection terminal of the single-pole triple-throw switch SW6 according to the first logic control signal.
[0081] At this time, the first logic control signal includes two different logic control signals, namely, the first logic control signal connected to the first control terminal of the single-pole three-throw switch SW6 is different from the first logic control signal connected to the second control terminal of the single-pole three-throw switch SW6.
[0082] In this embodiment, since the first connection terminal of the first single-pole single-throw switch SW4 and the input terminal of the low-noise amplifier LNA are respectively connected to the first connection terminal and the third connection terminal of the single-pole triple-throw switch SW6, the first single-pole single-throw switch SW4 can be removed, and the situation where the receiving amplification channel and the receiving bypass channel where the low-noise amplifier LNA is located simultaneously receive RF signals will not occur. If cost is not a concern, the first single-pole single-throw switch SW4 can also be retained.
[0083] The first connection terminal of the single-pole three-throw switch SW6 is set as SW6-1, the second connection terminal of the single-pole three-throw switch SW6 is set as SW6-2, the third connection terminal of the single-pole three-throw switch SW6 is set as SW6-3, the common terminal of the single-pole three-throw switch SW6 is set as SW6-4, the first control terminal of the single-pole three-throw switch SW6 is set as SW6-5, and the second control terminal of the single-pole three-throw switch SW6 is set as SW6-6.
[0084] When the RF front-end module 700 needs to transmit RF signals, SW6-5 and SW6-6 control SW6-2 and SW6-4 to connect according to the received first logic control signal, so that the RF signal transmitted by the signal transmission path TXIn is transmitted outward by the antenna ANT. When the RF front-end module 700 needs to receive RF signals, the antenna ANT receives the RF signal. If the received RF signal is a low-power signal, SW6-5 and SW6-6 control SW6-4 and SW6-3 to connect according to the received first logic control signal; if the received RF signal is a high-power signal, SW6-5 and SW6-6 control SW6-4 and SW6-1 to connect according to the received first logic control signal. This allows for more accurate control of the connection between the antenna ANT and the signal transmission path TXIn, the low-noise amplifier LNA, and the first single-pole single-throw switch SW4.
[0085] Of course, the first single-pole single-throw switch SW3 in the RF front-end module 200 of Embodiment 1, the RF front-end module 300 of Embodiment 2, the RF front-end module 400 of Embodiment 3, and the RF front-end module 500 of Embodiment 4 can also be replaced with the single-pole triple-throw RF switch SW6 in this embodiment.
[0086] It should be noted that the various embodiments described above with reference to the accompanying drawings are only illustrative of the present invention and not intended to limit its scope. Those skilled in the art should understand that any modifications or equivalent substitutions made to the present invention without departing from its spirit and scope should be covered within the scope of the present invention. Furthermore, unless the context otherwise requires, singular terms include plural forms, and vice versa. Additionally, unless specifically stated otherwise, all or part of any embodiment may be used in conjunction with all or part of any other embodiment.
Claims
1. A radio frequency (RF) front-end module, comprising a switching switch, a signal transmission path, and a signal reception path; the switching switch connects the signal transmission path and the signal reception path to an antenna respectively, and is used to switch the signal transmission path to be connected to the antenna, or to switch the signal reception path to be connected to the antenna; characterized in that, The signal receiving path includes a low-noise amplifier, a signal receiving terminal, a first single-pole single-throw switch, and an isolation circuit. The common terminal of the switching switch is used to connect to the antenna, and the input terminal of the switching switch is used to receive a first logic control signal. According to the received first logic control signal, the common terminal of the switching switch is controlled to connect to the signal transmission path, or to the first input terminal of the low noise amplifier, or / and connected to the first connection terminal of the first single-pole single-throw switch. The signal transmission path is used to transmit a first radio frequency signal; The control terminal of the low-noise amplifier is used to receive a second logic control signal and to control the low-noise amplifier to turn on or off according to the received second logic control signal. The signal receiving end is used to receive the second radio frequency signal; The control terminal of the first single-pole single-throw switch is used to receive a third logic control signal and to control the opening or closing of the first single-pole single-throw switch according to the received third logic control signal. The first input terminal of the isolation circuit is connected to the output terminal of the low-noise amplifier, the second input terminal of the isolation circuit is connected to the second connection terminal of the first single-pole single-throw switch, and the output terminal of the isolation circuit is connected to the signal receiving terminal. The isolation circuit is used to isolate the radio frequency signal between the output terminal of the low-noise amplifier and the output terminal of the first single-pole single-throw switch.
2. The radio frequency front-end module as described in claim 1, characterized in that, The switching switch is a first single-pole double-throw switch; the common terminal of the first single-pole double-throw switch serves as the common terminal of the switching switch; the first connection terminal of the first single-pole double-throw switch is connected to the first input terminal of the low-noise amplifier and the first connection terminal of the first single-pole double-throw switch respectively; the second connection terminal of the first single-pole double-throw switch is connected to the signal transmission path; the control terminal of the first single-pole double-throw switch serves as the input terminal of the switching switch and is used to control the common terminal of the first single-pole double-throw switch to connect to the first connection terminal or the second connection terminal of the first single-pole double-throw switch according to the first logic control signal.
3. The radio frequency front-end module as described in claim 1, characterized in that, The switching switch is a single-pole triple-throw switch; the common terminal of the single-pole triple-throw switch serves as the common terminal of the switching switch; the first connection terminal of the single-pole triple-throw switch is connected to the first connection terminal of the first single-pole single-throw switch; the second connection terminal of the single-pole triple-throw switch is connected to the signal transmission path; the third connection terminal of the single-pole triple-throw switch is connected to the first input terminal of the low-noise amplifier; the first control terminal and the second control terminal of the single-pole triple-throw switch together serve as the input terminal of the switching switch, and are used to control the common terminal of the single-pole triple-throw switch to connect to one of the first connection terminal, the second connection terminal, and the third connection terminal of the single-pole triple-throw switch according to the first logic control signal.
4. The radio frequency front-end module as described in claim 2 or 3, characterized in that, The isolation circuit includes a first resistor; the first end of the first resistor serves as the first input terminal of the isolation circuit, and the second end of the first resistor serves as both the second input terminal and the output terminal of the isolation circuit.
5. The radio frequency front-end module as described in claim 4, characterized in that, The isolation circuit also includes a second resistor and a third resistor; The first terminal of the second resistor is connected to the first terminal of the first resistor; The first end of the third resistor is connected to the second end of the first resistor, and the second end of the third resistor is connected to the second end of the second resistor and then grounded.
6. The radio frequency front-end module as described in claim 2 or 3, characterized in that, The isolation circuit includes a fourth resistor, a fifth resistor, and a sixth resistor; The first terminal of the fourth resistor serves as the first input terminal of the isolation circuit. The first end of the fifth resistor is connected to the second end of the fourth resistor, and the second end of the fifth resistor serves as both the second input end and the output end of the isolation circuit. The first end of the sixth resistor is connected to the second end of the fourth resistor, and the second end of the sixth resistor is grounded.
7. The radio frequency front-end module as described in claim 2 or 3, characterized in that, The isolation circuit includes a second single-pole single-throw switch; the first connection terminal of the second single-pole single-throw switch is connected to the output terminal of the low-noise amplifier, the second connection terminal of the second single-pole single-throw switch is connected to the first input terminal of the isolation circuit, and the control terminal of the second single-pole single-throw switch is used to receive a fourth logic control signal and to control the opening or closing of the second single-pole single-throw switch according to the received fourth logic control signal.
8. The radio frequency front-end module as described in claim 7, characterized in that, The second single-pole single-throw switch and the first single-pole single-throw switch are combined to form a second single-pole double-throw switch; The first connection terminal of the second single-pole double-throw switch serves as both the first connection terminal of the second single-pole double-throw switch and the first input terminal of the isolation circuit. The second connection terminal of the second single-pole double-throw switch serves as both the first connection terminal of the first single-pole double-throw switch and the second input terminal of the isolation circuit. The common terminal of the second single-pole double-throw switch serves as both the second connection terminal of the first single-pole double-throw switch and the output terminal of the isolation circuit. The control terminal of the second single-pole double-throw switch serves as both the control terminal of the first single-pole double-throw switch and the control terminal of the second single-pole double-throw switch, and is used to receive a fifth logic control signal. Simultaneously, based on the received fifth logic control signal, the common terminal of the second single-pole double-throw switch is connected to either the first connection terminal or the second connection terminal of the second single-pole double-throw switch.
9. The radio frequency front-end module as described in claim 2 or 3, characterized in that, The isolation circuit is a circulator; the reflecting end of the circulator serves as the first input end of the isolation circuit, the output end of the circulator serves as the second input end of the isolation circuit, and the input end of the circulator serves as the output end of the isolation circuit.