Positive voltage control type high-power single-pole double-throw switch, chip and radio frequency front-end circuit

Abstract

The invention provides a positive voltage control type high-power single-pole double-throw switch, a chip and a radio frequency front-end circuit, and the switch comprises a voltage conversion module which generates reverse first and second switch control signals based on an external control voltage; first ends of the first switch stack module and the second switch stack module are respectively connected with the first radio frequency end and the second radio frequency end through the first capacitor and the second capacitor, and second ends are connected with the third radio frequency end through the third capacitor; the third switch stacking module is connected between the power supply voltage and the first end of the first switch stacking module; the fourth switch stacking module is connected between the power supply voltage and the first end of the second switch stacking module; the first switch stacking module and the fourth switch stacking module are controlled by a first switch control signal, and the second switch stacking module and the third switch stacking module are controlled by a second switch control signal; one end of the fourth capacitor is connected with the power supply voltage. The positive voltage control type high-power single-pole double-throw switch is simple and compact in structure, high in power capacity and beneficial to miniaturization and high integration level of a chip.

Description

Positive pressure controlled high-power single-pole double-throw switch, chip and RF front-end circuit Technical Field

[0001] This invention relates to the fields of semiconductors and radio frequency switches, and in particular to a positive voltage controlled high-power single-pole double-throw switch, chip, and radio frequency front-end circuit. Background Technology

[0002] GaAs pseudomorphic high electron mobility transistor (pHEMT) switches are widely used in the RF front-end of radar systems due to their advantages such as low loss, small size, high reliability, and fast switching speed. To ensure good isolation between the two ports, most switch designs employ a series-parallel structure. However, the pinch-off voltage of depletion-mode GaAs is less than zero, thus requiring negative voltage control. This increases the variety of power supply voltages required by the system, necessitating additional drive circuitry and increasing application complexity. Common positive-voltage controlled single-pole double-throw switches utilize a transistor source-floating structure, which achieves positive voltage control but results in reduced switch power capacity. Simultaneously, the trend towards system miniaturization places higher demands on chip integration.

[0003] Therefore, how to solve the problems of complex control and limited function of traditional negative pressure control single-pole double-throw switches, and the small power capacity of traditional positive pressure control single-pole double-throw switches, has become one of the urgent problems to be solved by those skilled in the art.

[0004] It should be noted that the above description of the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of the present invention and facilitating understanding by those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because they have been described in the background section of this invention. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a positive pressure controlled high-power single-pole double-throw switch, chip and radio frequency front-end circuit, to solve the problems of complex control and limited function of negative pressure controlled single-pole double-throw switches and small power capacity of positive pressure controlled single-pole double-throw switches in the prior art.

[0006] To achieve the above and other related objectives, the present invention provides a positive pressure controlled high-power single-pole double-throw switch, wherein the positive pressure controlled high-power single-pole double-throw switch comprises at least:

[0007] Voltage conversion module, first switch stack module, second switch stack module, third switch stack module, fourth switch stack module, first capacitor, second capacitor, third capacitor and fourth capacitor;

[0008] The input terminal of the voltage conversion module is connected to the power supply voltage and receives the external control voltage. Based on the external control voltage, it generates a first switch control signal and a second switch control signal; wherein the first switch control signal and the second switch control signal are inversely related.

[0009] The first terminal of the first switch stacking module is connected to the first radio frequency terminal via the first capacitor, and the control terminal receives the first switch control signal; the first terminal of the second switch stacking module is connected to the second radio frequency terminal via the second capacitor, and the control terminal receives the second switch control signal; the second terminals of both the first switch stacking module and the second switch stacking module are connected to the third radio frequency terminal via the third capacitor.

[0010] The first end of the third switch stacking module is connected to the power supply voltage, the second end is connected to the first end of the first switch stacking module, and the control end receives the second switch control signal; the first end of the fourth switch stacking module is connected to the power supply voltage, the second end is connected to the first end of the second switch stacking module, and the control end receives the first switch control signal.

[0011] One end of the fourth capacitor is connected to the power supply voltage, and the other end is grounded.

[0012] Optionally, the voltage conversion module includes a first inverting unit, a second inverting unit, a third inverting unit, a first resistor, and a second resistor;

[0013] The input terminal of the first inverting unit is connected to the external control voltage, and the external control voltage is inverted.

[0014] The input terminal of the second inverting unit is connected to the output terminal of the first inverting unit via the first resistor, and the output voltage of the first inverting unit is inverted to obtain the first switching control signal;

[0015] The input terminal of the third inverting unit receives the external control voltage via the second resistor, and inverts the external control voltage to obtain the second switch control signal.

[0016] Alternatively, at least one inverting unit includes a first transistor, a second transistor, and a third resistor;

[0017] The source of the first transistor is grounded, and its drain is connected to the drain of the second transistor via the third resistor; the source of the second transistor is connected to the power supply voltage; the gate of the first transistor serves as the input terminal of the corresponding inverting unit; the gate of the second transistor is connected to the drain of the first transistor and serves as the output terminal of the corresponding inverting unit.

[0018] Alternatively, the first transistor is implemented using an E-mode pHEMT field-effect transistor, and the second transistor is implemented using a D-mode pHEMT field-effect transistor.

[0019] Optionally, each switch stack module includes n transistors and n+1 bias resistors, where n is a natural number greater than or equal to 2;

[0020] The transistors are connected in series, and the two ends of the series structure serve as the first and second ends of the corresponding switch stack module, respectively.

[0021] The first bias resistor is connected between the first and second terminals of the corresponding switch stack module;

[0022] The second to the (n+1)th bias resistors correspond one-to-one with each transistor. One end is connected to the control terminal of the corresponding transistor, and the other end is connected together as the control terminal of the corresponding switch stack module.

[0023] Alternatively, each transistor can be implemented using a D-mode pHEMT field-effect transistor.

[0024] Alternatively, n can be set to 2~5.

[0025] Alternatively, the saturated output power of the positive pressure controlled high-power single-pole double-throw switch satisfies:

[0026] ;

[0027] in, To achieve saturated output power, This represents the drain-source breakdown voltage of a single transistor. This is the load impedance.

[0028] To achieve the above and other related objectives, the present invention also provides a chip, the chip comprising at least the above-described positive pressure controlled high-power single-pole double-throw switch.

[0029] To achieve the above and other related objectives, the present invention also provides a radio frequency (RF) front-end circuit, wherein the RF front-end circuit includes at least the aforementioned positive voltage controlled high-power single-pole double-throw switch; wherein the first RF terminal and the second RF terminal of the positive voltage controlled high-power single-pole double-throw switch serve as a transmitting connection terminal and a receiving connection terminal, respectively, and the third RF terminal serves as an antenna connection terminal.

[0030] As described above, the positive pressure controlled high-power single-pole double-throw switch, chip, and RF front-end circuit of the present invention have the following beneficial effects:

[0031] The positive voltage controlled high-power single-pole double-throw switch of the present invention adopts positive voltage control, with a simple and compact structure; and provides a stable DC bias for the transistors in the switch stack module through the fourth capacitor and the supply voltage, so that the PN junction of the transistor can be kept in reverse bias even when the input signal power is large, thereby improving the power capacity of the switch.

[0032] The power capacity of the positive pressure controlled high-power single-pole double-throw switch of this invention is close to the theoretically calculated maximum input power, demonstrating excellent performance.

[0033] Compared to traditional positive-voltage controlled single-pole double-throw switches, the positive-voltage controlled high-power single-pole double-throw switch of this invention uses a significantly reduced number of capacitors, which is beneficial for chip miniaturization. At the same time, the chip integrates a voltage conversion module, reducing the number of control ports and realizing a single-voltage controlled single-pole double-throw switch, further improving the chip integration. Attached Figure Description

[0034] Figure 1 shows a schematic diagram of the structure of the positive pressure controlled high-power single-pole double-throw switch of the present invention.

[0035] Figure 2 shows a schematic diagram of the voltage conversion module of the present invention.

[0036] Figure 3 shows a schematic diagram of the switch stacking module of the present invention.

[0037] Figure 4 shows a schematic diagram of the 1dB compression point of the positive pressure controlled high-power single-pole double-throw switch of the present invention as a function of frequency.

[0038] Figure 5 shows a schematic diagram of the insertion loss of the positive pressure controlled high-power single-pole double-throw switch of the present invention as a function of frequency.

[0039] Figure 6 shows a schematic diagram of the isolation degree of the positive pressure controlled high-power single-pole double-throw switch of the present invention as a function of frequency.

[0040] Component designation explanation

[0041] 1-Positive pressure controlled high-power single-pole double-throw switch; 10-Voltage conversion module; 101-First reverse unit; 102-Second reverse unit; 103-Third reverse unit; 11-First switch stacking module; 12-Second switch stacking module; 13-Third switch stacking module; 14-Fourth switch stacking module. Detailed Implementation

[0042] 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, and 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.

[0043] Please refer to Figures 1 to 6. It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the figures 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.

[0044] As shown in Figure 1, the present invention provides a positive pressure controlled high-power single-pole double-throw switch 1, which includes:

[0045] Voltage conversion module 10, first switch stacking module 11, second switch stacking module 12, third switch stacking module 13, fourth switch stacking module 14, first capacitor C1, second capacitor C2, third capacitor C3 and fourth capacitor C4.

[0046] As shown in Figure 1, the voltage conversion module 10 is connected to the supply voltage Vdd and receives the external control voltage Vc, and generates a first switching control signal V based on the external control voltage Vc. A and the second switch control signal V B Among them, the first switch control signal V A With the second switch control signal V B Reverse.

[0047] Specifically, as shown in Figure 2, in this example, the voltage conversion module 10 includes a first inverting unit 101, a second inverting unit 102, a third inverting unit 103, a first resistor R1, and a second resistor R2. The input terminal of the first inverting unit 101 is connected to an external control voltage Vc, and inverts the external control voltage Vc. The input terminal of the second inverting unit 102 is connected to the output terminal of the first inverting unit 101 via the first resistor R1, and inverts the output voltage of the first inverting unit 101 to obtain the first switch control signal V. A The input terminal of the third inverting unit 103 receives the external control voltage Vc via the second resistor R2, inverts the external control voltage Vc, and obtains the second switch control signal V. BFurthermore, in this example, each inverting unit includes a first transistor M1, a second transistor M2, and a third resistor R3; wherein the source of the first transistor M1 is grounded, and its drain is connected to the drain of the second transistor M2 via the third resistor R3; the source of the second transistor M2 is connected to the supply voltage Vdd. The gate of the first transistor M1 serves as the input terminal of the corresponding inverting unit; the gate of the second transistor M2 is connected to the drain of the first transistor M1 and serves as the output terminal of the corresponding inverting unit. As an example, this invention is fabricated using GaAs technology, wherein the first transistor M1 is implemented using an E-mode pHEMT field-effect transistor, and the second transistor M2 is implemented using a D-mode pHEMT field-effect transistor; in practical use, any device type capable of achieving the above functions is applicable to this invention.

[0048] Specifically, taking a supply voltage Vdd of 5V and a control voltage Vc of 5V / 0V as an example. When the external control voltage Vc is 5V, the first switch control signal V... A The voltage is 5V, and the second switch control signal is V. B When the external control voltage Vc is 0V, the first switch control signal V is 0V. A The voltage is 0V, and the second switch control signal V is... B It is 5V.

[0049] It should be noted that any circuit structure capable of reversing is applicable to the reversing unit of the present invention, and the structures of each reversing unit can be set to be the same or different; any structure capable of generating the internal switching control signal of the positive voltage control type high-power single-pole double-throw switch 1 based on the external control voltage Vc is applicable to the voltage conversion module 10 of the present invention; these will not be described in detail here.

[0050] As shown in Figure 1, the first terminal of the first switch stacking module 11 is connected to the first radio frequency terminal Port1 via the first capacitor C1, and the second terminal is connected to the first plate of the third capacitor C3. The control terminal receives the first switch control signal V. A The first switch stacking module 11 is based on the first switch control signal V. A The control is to turn the circuit on or off.

[0051] As shown in Figure 1, the first terminal of the second switch stacking module 12 is connected to the second RF terminal Port2 via the second capacitor C2, and the second terminal is connected to the first plate of the third capacitor C3. The control terminal receives the second switch control signal V. B The second switch stacking module 12 is based on the second switch control signal V. B The control switches the capacitor on or off. The second plate of the third capacitor C3 is connected to the third RF terminal, Port3.

[0052] As shown in Figure 1, the first terminal of the third switch stacking module 13 is connected to the power supply voltage Vdd, the second terminal is connected to the first terminal of the first switch stacking module 11, and the control terminal receives the second switch control signal V. B The third switch stacking module 13 is based on the second switch control signal V. B The control is to turn the circuit on or off.

[0053] As shown in Figure 1, the first terminal of the fourth switch stacking module 14 is connected to the power supply voltage Vdd, the second terminal is connected to the first terminal of the second switch stacking module 12, and the control terminal receives the first switch control signal V. A The fourth switch stacking module 14 is based on the first switch control signal V. A The control is to turn the circuit on or off.

[0054] Specifically, in this embodiment, each switch stack module includes n transistors and n+1 bias resistors, where n is a natural number greater than or equal to 2. The transistors are connected in series to form a series structure, with the two ends of the series structure serving as the first and second ends of the corresponding switch stack module, respectively. A first bias resistor is connected between the first and second ends of the corresponding switch stack module. The second to (n+1)th bias resistors correspond one-to-one with each transistor, with one end connected to the control terminal of the corresponding transistor and the other end connected together as the control terminal of the corresponding switch stack module. As an example, n is set to 3, as shown in Figure 3. The drain of the third transistor M3 serves as the drain D (first or second end) of the corresponding switch stack module, and its source is connected to the drain of the fourth transistor M4. The source of the fourth transistor M4 is connected to the drain of the fifth transistor M5. The source of the fifth transistor M5 serves as the source S (second or first end) of the corresponding switch stack module. One end of the first bias resistor Rp1 is connected to the drain D of the corresponding switch stack module, and the other end is connected to the source S of the corresponding switch stack module. The first end of the second bias resistor Rp2 is connected to the gate of the third transistor M3, the first end of the third bias resistor Rp3 is connected to the gate of the fourth transistor M4, and the first end of the fourth bias resistor Rp4 is connected to the gate of the fifth transistor M5; the second ends of the second bias resistor Rp2, the third bias resistor Rp3 and the fourth bias resistor Rp4 are connected together as the gate G (control terminal) of the switch stack module.

[0055] It should be noted that transistors are inherently symmetrical, therefore the source and drain of the switch stack module can be used interchangeably. In this example, the source is set as the first terminal and the drain as the second terminal; in other examples, the drain can also be set as the first terminal and the source as the second terminal. The number of series transistors n in each switch stack module can be set according to actual needs. The larger n is, the greater the power tolerance of the switch, but too many stacked transistors will lead to inconsistent voltage division (requiring additional circuitry); as an example, n is set to 2-5 levels (e.g., in GaAs technology).

[0056] Furthermore, in this example, each transistor in the switch stack module is implemented using a D-mode pHEMT field-effect transistor, whose pinch-off voltage Vp is negative. The on / off state is determined by the gate-source voltage Vgs; when Vgs ≤ Vp, the switch is off, and when Vgs > Vp, the switch is on. This invention utilizes pHEMT field-effect transistors as switches to achieve advantages such as low loss, small size, high reliability, and fast switching speed; other switching transistors can also be used in practical applications.

[0057] As shown in Figure 1, one end of the fourth capacitor C4 is connected to the power supply voltage Vdd, and the other end is grounded.

[0058] Specifically, the present invention provides a stable DC bias to the first terminal (source in this example) of the switch stack module by setting the fourth capacitor C4, thereby ensuring that the bias voltage does not drift.

[0059] In this invention, after n-stage transistor stacking, the saturated output power of the switch is determined by the total breakdown voltage of the stacked structure. Ideally, the total breakdown voltage after stacking is the product of the drain-source breakdown voltage Vds_breakdown of a single transistor and the number of stacking stages n. Therefore, the saturated output power of the positive voltage controlled high-power single-pole double-throw switch 1 of this invention satisfies:

[0060] ;

[0061] in, To achieve saturated output power, The load impedance is given. With a supply voltage Vdd of 5V and an external control voltage Vc of 5V / 0V, the maximum output power of the positive voltage controlled high-power single-pole double-throw switch 1 of this invention is calculated to be 5.76W, or 37.6dBm, as shown by the dashed line in Figure 4. The simulation results of the IP1dB (input 1dB compression point power) of the single-pole double-throw switch of this invention are shown by the solid line in Figure 4. The simulation results show that the IP1dB of this single-pole double-throw switch is above 36dBm, and the power capacity is close to the theoretically calculated maximum output power. The insertion loss of the positive voltage controlled high-power single-pole double-throw switch 1 of this invention varies with frequency as shown in Figure 5, and the isolation varies with frequency as shown in Figure 6.

[0062] This invention also provides a chip, including the positive voltage controlled high-power single-pole double-throw switch 1 of this invention, which integrates a voltage conversion module 10, a first switch stacking module 11, a second switch stacking module 12, a third switch stacking module 13, a fourth switch stacking module 14, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a fourth capacitor C4 into the same chip. Because this invention reduces the number of DC blocking capacitors used (only four are used), the chip size can be effectively reduced; at the same time, the on-chip integration of the voltage conversion module can further reduce the number of control ports and improve the chip integration density.

[0063] This invention also provides a radio frequency (RF) front-end circuit, which includes at least the positive voltage controlled high-power single-pole double-throw switch 1 of this invention; wherein, the first RF terminal and the second RF terminal of the positive voltage controlled high-power single-pole double-throw switch 1 serve as a transmit connection terminal (TX Port) and a receive connection terminal (RX Port), respectively, and the third RF terminal serves as an antenna connection terminal (ANT Port). The RF front-end circuit also includes, but is not limited to, transmit and receive paths, which will not be described in detail here. As an example, the RF front-end circuit of this invention can be applied to a digital phased array system.

[0064] In summary, this invention provides a positive voltage controlled high-power single-pole double-throw switch, chip, and RF front-end circuit, comprising: a voltage conversion module, a first switch stacking module, a second switch stacking module, a third switch stacking module, a fourth switch stacking module, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor; wherein, the input terminal of the voltage conversion module is connected to the power supply voltage and receives an external control voltage, and generates a first switch control signal and a second switch control signal based on the external control voltage; the first switch control signal and the second switch control signal are inversely related; the first terminal of the first switch stacking module is connected to a first RF terminal via the first capacitor, and the control terminal receives the first switch control signal; the first terminal of the second switch stacking module is connected to a second RF terminal via the second capacitor, and the control terminal receives the second switch control signal; the second terminals of both the first and second switch stacking modules are connected to a third RF terminal via the third capacitor; the first terminal of the third switch stacking module is connected to the power supply voltage, the second terminal is connected to the first terminal of the first switch stacking module, and the control terminal receives the second switch control signal; the first terminal of the fourth switch stacking module is connected to the power supply voltage, the second terminal is connected to the first terminal of the second switch stacking module, and the control terminal receives the first switch control signal; one terminal of the fourth capacitor is connected to the power supply voltage, and the other terminal is grounded. The positive voltage controlled high-power single-pole double-throw switch of this invention provides a stable DC bias for the transistors in the switch stack module through DC blocking capacitors and external power supply. This achieves high power capacity while reducing the number of DC blocking capacitors inside the chip, thus enabling chip miniaturization. Simultaneously, the chip integrates a voltage conversion module, reducing the number of control ports and increasing the chip's integration density. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial applicability.

[0065] 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 positive pressure controlled high-power single-pole double-throw switch, characterized in that, The positive-voltage controlled high-power single-pole double-throw switch includes at least: a voltage conversion module, a first switch stacking module, a second switch stacking module, a third switch stacking module, a fourth switch stacking module, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor; the input terminal of the voltage conversion module is connected to the power supply voltage and receives an external control voltage, and generates a first switch control signal and a second switch control signal based on the external control voltage; wherein, the first switch control signal and the second switch control signal are inversely related; the first terminal of the first switch stacking module is connected to a first radio frequency terminal via the first capacitor, and the control terminal receives the first switch control signal; the first terminal of the second switch stacking module is connected to a second radio frequency terminal via the second capacitor, and the control terminal receives the second switch control signal; the second terminals of both the first and second switch stacking modules are connected to a third radio frequency terminal via the third capacitor; the first terminal of the third switch stacking module is connected to the power supply voltage, the second terminal is connected to the first terminal of the first switch stacking module, and the control terminal receives the second switch control signal; the first terminal of the fourth switch stacking module is connected to the power supply voltage, the second terminal is connected to the first terminal of the second switch stacking module, and the control terminal receives the first switch control signal; one terminal of the fourth capacitor is connected to the power supply voltage, and the other terminal is grounded.

2. The positive pressure controlled high-power single-pole double-throw switch according to claim 1, characterized in that: The voltage conversion module includes a first inverting unit, a second inverting unit, a third inverting unit, a first resistor, and a second resistor; the input terminal of the first inverting unit is connected to the external control voltage and inverts the external control voltage; the input terminal of the second inverting unit is connected to the output terminal of the first inverting unit via the first resistor and inverts the output voltage of the first inverting unit to obtain the first switch control signal. The input terminal of the third inverting unit receives the external control voltage via the second resistor, and inverts the external control voltage to obtain the second switch control signal.

3. The positive pressure controlled high-power single-pole double-throw switch according to claim 2, characterized in that: At least one inverting unit includes a first transistor, a second transistor, and a third resistor; the source of the first transistor is grounded, and its drain is connected to the drain of the second transistor via the third resistor; the source of the second transistor is connected to the supply voltage; the gate of the first transistor serves as the input terminal of the corresponding inverting unit; the gate of the second transistor is connected to the drain of the first transistor and serves as the output terminal of the corresponding inverting unit.

4. The positive pressure controlled high-power single-pole double-throw switch according to claim 3, characterized in that: The first transistor is implemented using an E-mode pHEMT field-effect transistor, and the second transistor is implemented using a D-mode pHEMT field-effect transistor.

5. The positive pressure controlled high-power single-pole double-throw switch according to claim 1, characterized in that: Each switch stack module includes n transistors and n+1 bias resistors, where n is a natural number greater than or equal to 2; the transistors are connected in series, and the two ends of the series structure serve as the first and second ends of the corresponding switch stack module; the first bias resistor is connected between the first and second ends of the corresponding switch stack module; the second to the (n+1)th bias resistors correspond one-to-one with each transistor, with one end connected to the control terminal of the corresponding transistor and the other end connected together as the control terminal of the corresponding switch stack module.

6. The positive pressure controlled high-power single-pole double-throw switch according to claim 5, characterized in that: Each transistor is implemented using a D-mode pHEMT field-effect transistor.

7. The positive pressure controlled high-power single-pole double-throw switch according to claim 5 or 6, characterized in that: n is set to 2~5.

8. The positive pressure controlled high-power single-pole double-throw switch according to claim 5 or 6, characterized in that: The saturated output power of the positive pressure controlled high-power single-pole double-throw switch satisfies: ;in, To achieve saturated output power, This represents the drain-source breakdown voltage of a single transistor. This is the load impedance.

9. A chip, characterized in that, The chip includes at least one positive pressure controlled high-power single-pole double-throw switch as described in any one of claims 1-8.

10. A radio frequency front-end circuit, characterized in that, The radio frequency front-end circuit includes at least the positive pressure controlled high-power single-pole double-throw switch as described in any one of claims 1-8; wherein the first radio frequency terminal and the second radio frequency terminal of the positive pressure controlled high-power single-pole double-throw switch serve as the transmitting connection terminal and the receiving connection terminal, respectively, and the third radio frequency terminal serves as the antenna connection terminal.

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