A CMOS voltage-controlled oscillator applied to anti-interference unmanned aerial vehicle millimeter wave radar

Abstract

The application relates to a CMOS voltage-controlled oscillator applied to an anti-interference unmanned aerial vehicle millimeter wave radar and belonging to the millimeter wave radar design field, which comprises a resonance circuit, a negative resistance active circuit and two switch circuits with the same structure. The resonance circuit comprises a switch capacitor, a direct-current isolation capacitor, a resonance capacitor, a grounding resistor, a tuning resistor and a resonance inductor; the negative resistance active circuit comprises a cross-coupled MOS pair and a current source; and the switch circuits each comprise a switch MOS, a grounding resistor and a switch-coupled inductor. The application utilizes a dual-phase transformer structure to make the resonance inductor and the switch-coupled inductor mutually inductive, thereby changing the inductance value of the resonance inductor and realizing frequency band switching; the combination of switch capacitor conduction and shutdown and switch-coupled inductor conduction and shutdown is used to realize VCO bandwidth tuning; the CMOS process is adopted for design, and the VCO is miniaturized and integrated. While the performance of the voltage-controlled oscillator and the layout area are ensured, a full-frequency-band wide-band tuning range is realized, thereby improving the detection capability and resolution of the millimeter wave radar, realizing frequency hopping communication and spread spectrum communication of the unmanned aerial vehicle, and effectively improving the anti-interference capability and safety of the unmanned aerial vehicle.

Description

Technical Field

[0001] This invention belongs to the field of millimeter-wave radar design and relates to a CMOS voltage-controlled oscillator for use in anti-jamming UAV millimeter-wave radar. Background Technology

[0002] With breakthroughs in related technologies, drone technology has developed rapidly and been widely applied. In today's era of rapid technological advancement, the application scenarios for drones are constantly expanding, from initial applications in photography and agricultural spraying to today's multi-functional services such as building cleaning and logistics transportation. Currently, with increasing instability in the international situation, drones are also being used in a range of situations, including armed attacks and battlefield interference. As the application of drones in various fields continues to increase, drones face numerous challenges, such as severe environmental and human interference, thus placing higher demands on their safety, reliability, adaptability, and anti-interference capabilities in complex environments.

[0003] Millimeter-wave radar is a key sensor in UAV flight control systems, and its ability to perform various tasks with precision is inseparable from its capabilities. Currently, the limited perception capabilities of UAVs remain a major obstacle to intelligent flight control systems, potentially leading to accidental collisions, mission failures, and property damage. The most common obstacle avoidance technologies for UAVs include millimeter-wave radar, infrared sensors, ultrasonic sensors, laser sensors, and visual sensors. Compared to other sensors, millimeter-wave radar boasts advantages such as small size, light weight, low power consumption, high stability, long detection range, ability to track multiple targets, high accuracy, high data refresh rate, wide spectral range, high distance resolution, high velocity sensitivity, strong penetration capability, strong anti-interference, and strong anti-stealth capability, perfectly meeting the stringent requirements of UAVs regarding size, weight, power consumption, detection range, real-time performance, and anti-detection capabilities. As a crucial radio frequency component in millimeter-wave radar, broadband millimeter-wave voltage-controlled oscillators can further improve the radar's detection capabilities and resolution while reducing system costs.

[0004] Unmanned aerial vehicle (UAV) anti-jamming technology refers to the adoption of corresponding technical means and measures to improve the anti-jamming capability of UAV systems and ensure their stable operation in complex environments in response to various interference methods. Common UAV anti-jamming technologies include frequency hopping communication, spread spectrum communication, anti-jamming antennas, encrypted communication, intelligent identification, and interference suppression. Among them, frequency hopping communication continuously changes the communication frequency, making it impossible for interference signals to accurately track and interfere with the UAV's communication link, thereby effectively improving the anti-jamming capability and security of the UAV communication system. Spread spectrum communication uses a broadband transmission method to distribute the signal across a wider frequency band, thereby reducing the impact of interference signals on UAV communication and improving the anti-multipath interference and anti-jamming capability of the UAV communication system. As an important part of the radio frequency in millimeter-wave radar, a voltage-controlled oscillator (VCO) capable of operating in three millimeter-wave frequency bands enables UAVs to perform frequency hopping and spread spectrum communication, thereby further improving the UAV's anti-jamming capability and ensuring its normal operation and performance.

[0005] At the 2019 World Radiocommunication Conference, the unified operating frequency bands for millimeter waves were defined as 24.25 GHz–27.5 GHz, 37 GHz–43.5 GHz, and 66 GHz–71 GHz. These bands have wide bandwidths and high frequencies, making the design and implementation of a voltage-controlled oscillator (VCO) with low phase noise, low power consumption, and a wide tuning range quite challenging. Currently, most VCO designs operate in the 24.25 GHz–27.5 GHz range, with a few operating in both 24.25 GHz–27.5 GHz and 37 GHz–43.5 GHz ranges; no VCO has been found to operate in all three bands. Furthermore, compared to other processes, CMOS-based VCOs offer advantages such as high integration, miniaturization, low cost, low power consumption, system simplification, robustness, wide voltage regulation range, and strong anti-interference capabilities.

[0006] Therefore, in order to meet the stringent requirements of UAVs on indicators such as size, weight, power consumption, detection range, real-time performance, and anti-detection, it is of great significance to study how to achieve a wide-band tuning range across the entire frequency range while ensuring the performance and layout area of ​​the voltage-controlled oscillator, thereby improving the detection capability and resolution of millimeter-wave radar, enabling UAVs to achieve frequency hopping communication and spread spectrum communication, and effectively improving the anti-interference capability and security of UAVs. Summary of the Invention

[0007] To address the aforementioned problems in the prior art, this invention provides a CMOS voltage-controlled oscillator for use in anti-jamming UAV millimeter-wave radar. The technical problem to be solved by this invention is achieved through the following technical solution:

[0008] This invention provides a CMOS voltage-controlled oscillator for use in anti-jamming UAV millimeter-wave radar, comprising:

[0009] Resonant circuit, negative resistance active circuit, and switching circuit 1 and switching circuit 2 with the same structure.

[0010] The resonant circuit includes: a switched capacitor, a DC blocking capacitor, a resonant capacitor, a grounding resistor, a tuning resistor, and a resonant inductor. In the resonant circuit, the DC blocking capacitor C1, the grounding resistor R1, the switched capacitor Var1, the tuning resistor R3, the switched capacitor Var2, the grounding resistor R2, and the DC blocking capacitor C2 are connected in series. The other ends of the DC blocking capacitors C1 and C2 are respectively connected to the two ends of the resonant inductor L1. The other ends of the grounding resistors R1 and R2 are both grounded. The other end of the tuning resistor R3 is connected to the input control voltage Vctrl1. The resonant capacitors C3 and C4 are connected in series, and the other ends of the resonant capacitors C3 and C4 are respectively connected to the two ends of the resonant inductor L1.

[0011] The negative resistance active circuit includes a cross-coupled pair MOSFET and a current source. In the negative resistance active circuit, the drains of the cross-coupled pair MOSFET M1 and M2 are respectively connected to the two ends of the resonant inductor L1. The gate of the cross-coupled pair MOSFET M1 is connected to the drain of the cross-coupled pair MOSFET M2, the drain of the cross-coupled pair MOSFET M1 is connected to the gate of the cross-coupled pair MOSFET M2, the source of the cross-coupled pair MOSFET M1 is connected to the source of the cross-coupled pair MOSFET M2, and is connected in series with the input terminal of the current source I1. The output terminal of the current source I1 is grounded.

[0012] Each switching circuit includes a switching coupling inductor and a switching MOSFET. In switching circuit 1, the two ends of the switching coupling inductor L2 are connected to the drain and source of the switching MOSFET M3, respectively. The base of the switching MOSFET M3 is connected to the control voltage Vctrl2. Both the drain and source are connected to grounding resistors R4 and R5, and the other ends of grounding resistors R4 and R5 are grounded. In switching circuit 2, the two ends of the switching coupling inductor L3 are connected to the drain and source of the switching MOSFET M4. The base of the switching MOSFET M4 is connected to the control voltage Vctrl3. Both the drain and source are connected to grounding resistors R6 and R7, and the other ends of grounding resistors R6 and R7 are grounded.

[0013] Furthermore, the first voltage-controlled oscillator unit includes a resonant circuit and a negative resistance active circuit, the second voltage-controlled oscillator unit includes a resonant circuit, a switching circuit 1 and a negative resistance active circuit, and the third voltage-controlled oscillator unit includes a resonant circuit, a switching circuit 2 and a negative resistance active circuit.

[0014] Furthermore, by changing the voltage difference across the varactor tube, the capacitance value is changed, thereby altering the resonant frequency and achieving continuous adjustment of the output frequency.

[0015] Furthermore, by adjusting the control voltages Vctrl2 / Vctrl3, the conduction and turn-off of the switching MOSFETs M3 / M4 are controlled, thereby controlling whether the switching coupling inductors L2 / L3 are connected to the transformer. By changing the coupling coefficient of the transformer, the resonant inductance value of the LC circuit in the resonant circuit is changed, thereby changing the frequency of the oscillation signal, thus achieving the purpose of expanding the bandwidth.

[0016] Furthermore, the resonant inductor L1, the switch-coupled inductor L2, and the switch-coupled inductor L3 are arranged sequentially from the inside out.

[0017] Furthermore, the resonant inductor L1, the switch-coupled inductor L2, and the switch-coupled inductor L3 in the resonant circuit form a two-phase transformer structure, wherein the switch-coupled inductors L2 and L3 are the input windings, and the resonant inductor L1 is the output winding.

[0018] Furthermore, when the voltage-controlled oscillator (VCO) is operating, only one VCO unit works normally at a time. When the first VCO unit is operating, the VCO outputs a high-frequency signal with a frequency range of 66 GHz to 71 GHz. When the second VCO unit is operating, the VCO outputs a mid-frequency signal with a frequency range of 37 GHz to 43.5 GHz. When the third VCO unit is operating, the VCO outputs a low-frequency signal with a frequency range of 24.25 GHz to 27.5 GHz.

[0019] The beneficial effects of this invention are as follows:

[0020] The schematic diagram of a CMOS voltage-controlled oscillator for anti-jamming UAV millimeter-wave radar described in this invention is as follows: Figure 1 As shown. This invention utilizes a two-phase transformer structure to make the resonant inductor and the switching coupled inductor mutually inductant, thereby changing the inductance value of the resonant inductor and achieving frequency band switching; by combining the on and off states of the switched capacitor and the switched coupled inductor, the VCO bandwidth is tuned; and CMOS technology is used for design to achieve miniaturization and integration of the VCO. While ensuring the performance and layout area of ​​the voltage-controlled oscillator, a wide-bandwidth tuning range is achieved, thereby improving the detection capability and resolution of millimeter-wave radar, enabling UAVs to achieve frequency hopping communication and spread spectrum communication, and improving the anti-interference capability and security of UAVs. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a CMOS voltage-controlled oscillator applied to anti-jamming UAV millimeter-wave radar according to the present invention;

[0022] Figure 2 This is a schematic diagram of the transformer described in this invention. Detailed Implementation

[0023] To further understand the present invention, the technical solutions of the present invention will be described below in conjunction with the accompanying drawings and specific embodiments. These descriptions are only for further explaining the features and advantages of the present invention, but the scope of protection of the present invention is not limited thereto.

[0024] This invention provides a CMOS voltage-controlled oscillator for use in anti-jamming UAV millimeter-wave radar, such as... Figure 1 As shown, it may include:

[0025] It includes resonant circuits, negative resistance active circuits, and switching circuits 1 and 2 with the same structure.

[0026] The resonant circuit includes: a switched capacitor, a DC blocking capacitor, a resonant capacitor, a grounding resistor, a tuning resistor, and a resonant inductor. In the resonant circuit, the DC blocking capacitor C1, the grounding resistor R1, the switched capacitor Var1, the tuning resistor R3, the switched capacitor Var2, the grounding resistor R2, and the DC blocking capacitor C2 are connected in series. The other ends of the DC blocking capacitors C1 and C2 are respectively connected to the two ends of the resonant inductor L1. The other ends of the grounding resistors R1 and R2 are both grounded. The other end of the tuning resistor R3 is connected to the input control voltage Vctrl1. The resonant capacitors C3 and C4 are connected in series, and the other ends of the resonant capacitors C3 and C4 are respectively connected to the two ends of the resonant inductor L1.

[0027] The negative resistance active circuit includes a cross-coupled pair MOSFET and a current source. In the negative resistance active circuit, the drains of the cross-coupled pair MOSFET M1 and M2 are respectively connected to the two ends of the resonant inductor L1. The gate of the cross-coupled pair MOSFET M1 is connected to the drain of the cross-coupled pair MOSFET M2, the drain of the cross-coupled pair MOSFET M1 is connected to the gate of the cross-coupled pair MOSFET M2, the source of the cross-coupled pair MOSFET M1 is connected to the source of the cross-coupled pair MOSFET M2, and is connected in series with the input terminal of the current source I1. The output terminal of the current source I1 is grounded.

[0028] Each switching circuit includes a switching coupling inductor and a switching MOSFET. In switching circuit 1, the two ends of the switching coupling inductor L2 are connected to the drain and source of the switching MOSFET M3, respectively. The base of the switching MOSFET M3 is connected to the control voltage Vctrl2. Both the drain and source are connected to grounding resistors R4 and R5, and the other ends of grounding resistors R4 and R5 are grounded. In switching circuit 2, the two ends of the switching coupling inductor L3 are connected to the drain and source of the switching MOSFET M4. The base of the switching MOSFET M4 is connected to the control voltage Vctrl3. Both the drain and source are connected to grounding resistors R6 and R7, and the other ends of grounding resistors R6 and R7 are grounded.

[0029] In this embodiment of the invention, the three inductors are designed as transformers, and the chip area occupied by the inductors is reduced by overlapping large and small areas. Figure 2 As shown, the resonant inductor L1 and the switch-coupled inductors L2 and L3 in the resonant circuit form a two-phase transformer structure. The resonant inductor L1, the switch-coupled inductor L2, and the switch-coupled inductor L3 are arranged in sequence from the inside to the outside. The switch-coupled inductors L2 and L3 are the input windings, and the resonant inductor L1 is the output winding.

[0030] In embodiments of the present invention, such as Figure 2 As shown, the switching coupling inductors L2 and L3 are octagonal inductors, and the resonant inductor L1 is an octagonal inductor with a center tap, thereby improving the inductor symmetry and reducing the layout area.

[0031] In this embodiment of the invention, the coupling between the resonant inductor L1 and the switch-coupled inductors L2 and L3 is relatively strong, while the coupling between the switch-coupled inductors L2 and L3 is relatively weak.

[0032] In this embodiment of the invention, the transformer consists of multiple sets of inductors, therefore different metal layers are used to prevent metal overlap. The resonant inductor L1 uses the thickest metal layer in this design process, which has relatively small parasitic resistance and other related parameters, low loss, and high Q value. The switching coupling inductors L2 and L3 use the metal layer adjacent to the resonant inductor L1.

[0033] In this embodiment of the invention, the resonant inductor L1, resonant capacitors C3 and C4, DC blocking capacitors C1 and C2, grounding resistors R1 and R2, tuning resistor R3, and switched capacitors Var1 and Var2 constitute the resonant cavity of the first voltage-controlled oscillator unit. The resonant inductor L1, switched coupling inductor L2, resonant capacitors C3 and C4, DC blocking capacitors C1 and C2, grounding resistors R1 and R2, tuning resistor R3, and switched capacitors Var1 and Var2 constitute the resonant cavity of the second voltage-controlled oscillator unit. The resonant inductor L1, switched coupling inductor L2 and L3, resonant capacitors C3 and C4, DC blocking capacitors C1 and C2, grounding resistors R1 and R2, tuning resistor R3, and switched capacitors Var1 and Var2 constitute the resonant cavity of the third voltage-controlled oscillator unit.

[0034] In this embodiment of the invention, the negative resistance active circuit adopts an NMOS row cross-coupled structure and uses an NMOS transistor as the negative resistance unit of the voltage-controlled oscillator. Compared with other structures, it has a smaller layout and smaller parasitic capacitance while achieving the same transconductance, which is more conducive to achieving a wide bandwidth.

[0035] In this embodiment of the invention, the cross-coupling in the negative resistance active circuit provides negative resistance to the MOS transistor to compensate for the loss of the resonant cavity, thereby enabling the circuit to generate an oscillation signal.

[0036] In this embodiment of the invention, resistors R1, R2, and R3 all serve to prevent signal and current leakage. Resistors R4, R5, R6, and R7, on the one hand, prevent radio frequency signals from leaking to ground, and on the other hand, provide a 0V potential to the drain and source of the switching MOSFETs M2 and M3.

[0037] In this embodiment of the invention, controlling the switching on and off of the switching inductor is considered as coarsely adjusting the bandwidth of the voltage-controlled oscillator. By adjusting the magnitude of the control voltages Vctrl2 / Vctrl3, the on and off of the switching MOSFETs M3 / M4 are controlled, thereby controlling whether the switching inductors L2 / L3 are connected to the transformer. When both switching MOSFETs M3 and M4 are off, no switching inductor is connected to the transformer, the inductance value of the resonant inductor L1 remains unchanged, and the circuit outputs a high-frequency signal. When switching MOSFETs M3 is on and M4 is off, only the switching inductor L2 is connected to the transformer, the resonant inductor L1 and the switching inductor L2 are mutually inductant, the inductance value of the resonant inductor L1 increases, and the circuit outputs a mid-frequency signal. When both switching MOSFETs M3 and M4 are turned on, the switching coupling inductors L2 and L3 are connected to the transformer. The resonant inductor L1, in addition to its mutual inductance with the switching coupling inductor L2, is further mutually inducted with the switching coupling inductor L3. The inductance of the resonant inductor L1 is at its maximum, and the circuit outputs a low-frequency signal. This method changes the coupling coefficient of the transformer, thereby altering the resonant inductance of the LC loop in the resonant circuit, and thus changing the frequency of the oscillation signal, thereby expanding the bandwidth.

[0038] In this embodiment of the invention, controlling the switching capacitor to turn on and off is considered as fine-tuning the bandwidth of the voltage-controlled oscillator. Since one end of the varactor is at a potential of 0V, and the potential at the other end is determined by the tuning voltage Vctrl1, changing the voltage difference across the varactor in the resonant circuit, i.e., changing the voltage value of Vctrl1, changes the capacitance value, thereby changing the resonant frequency and achieving continuous adjustment of the output frequency.

[0039] In this embodiment of the invention, the center frequency, total resonant inductance, and total resonant capacitance C of the voltage-controlled oscillator (VCO) change in different operating frequency bands. By reasonably selecting the above parameters, the VCO can oscillate in different frequency bands. When the first VCO is working, the resonant inductance L1 is 68.96 pH, the total resonant capacitance is 4.819 fF, and the values ​​of the switched capacitors Var1 and Var2 range from 0 to 0.37 fF. When the second VCO unit is working, the resonant inductance L1 is 11.11 pH, the total resonant capacitance is 12.5 fF, and the values ​​of the switched capacitors Var1 and Var2 range from 0 to 2.29 fF. When the third VCO unit is working, the resonant inductance L1 is 172.4 pH, the total resonant capacitance is 174.705 fF, and the values ​​of the switched capacitors Var1 and Var2 range from 0 to 15.3 fF.

[0040] In this embodiment of the invention, only one voltage-controlled oscillator unit operates normally at a time. When the first voltage-controlled oscillator unit operates, the voltage-controlled oscillator outputs a high-frequency signal with a frequency range of 67.5 GHz to 72.5 GHz. When the second voltage-controlled oscillator unit operates, the voltage-controlled oscillator outputs a mid-frequency signal with a frequency range of 38.5 GHz to 45 GHz. When the third voltage-controlled oscillator unit operates, the voltage-controlled oscillator outputs a low-frequency signal with a frequency range of 26.75 GHz to 29 GHz.

[0041] It should be noted that, in the description of this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A CMOS voltage-controlled oscillator applied to an anti-interference unmanned aerial vehicle millimeter wave radar, characterized by: The resonant circuit, the negative resistance active circuit and the switch circuit 1 and the switch circuit 2 have the same structure; The resonant circuit comprises a switch capacitor, a DC blocking capacitor, a resonant capacitor, a grounding resistor, a tuning resistor and a resonant inductor; the DC blocking capacitor C1, the grounding resistor R1, the switch capacitor Var1, the tuning resistor R3, the switch capacitor Var2, the grounding resistor R2 and the DC blocking capacitor C2 are connected in series; the other ends of the DC blocking capacitors C1 and C2 are connected to the two ends of the resonant inductor L1; the other ends of the grounding resistors R1 and R2 are grounded; the other end of the tuning resistor R3 is connected to an input control voltage Vctrl1; the resonant capacitors C3 and C4 are connected in series and the two ends thereof are connected to the two ends of the resonant inductor L1; The negative resistance active circuit comprises a cross-coupled MOS pair and a current source; the drain of the MOS M1 and the drain of the MOS M2 are connected to the two ends of the resonant inductor L1; the gate of the MOS M1 is connected to the drain of the MOS M2; the drain of the MOS M1 is connected to the gate of the MOS M2; the source of the MOS M1 is connected to the source of the MOS M2 and the input of the current source I1; the output of the current source I1 is grounded; The switch circuit 1 comprises a switch coupling inductor and a switch MOS; the two ends of the switch coupling inductor L2 are connected to the drain and the source of the switch MOS M3; the base of the switch MOS M3 is connected to a control voltage Vctrl2; the drain and the source of the switch MOS M3 are grounded through the grounding resistors R4 and R5 respectively; The switch circuit 2 comprises a switch coupling inductor and a switch MOS; the two ends of the switch coupling inductor L3 are connected to the drain and the source of the switch MOS M4; the base of the switch MOS M4 is connected to a control voltage Vctrl3; the drain and the source of the switch MOS M4 are grounded through the grounding resistors R6 and R7 respectively; The voltage-controlled oscillator is a reconfigurable oscillator; the on and off of the switch MOS M3 or M4 is controlled by adjusting the size of the control voltage Vctrl2 or Vctrl3, so as to control whether the switch coupling inductor L2 or L3 is connected to the transformer, change the coupling coefficient of the transformer, and further change the inductance value of the resonant inductor L1 in the resonant circuit, so as to change the frequency of the oscillation signal, so as to achieve the purpose of expanding the bandwidth and multi-frequency band output; according to the on and off state of the switch MOS M3 and M4, three different working modules are divided, which are a first voltage-controlled oscillation unit, a second voltage-controlled oscillation unit and a third voltage-controlled oscillation unit; only one voltage-controlled oscillation unit works in each frequency band; The first voltage-controlled oscillation unit is composed of the resonant circuit and the negative resistance active circuit; when the first voltage-controlled oscillation unit works, the switch MOS M3 and M4 are cut off; at this time, the voltage-controlled oscillator outputs a high-frequency signal, and the frequency range of the output signal is 66GHz~71GHz; The second voltage-controlled oscillation unit is composed of the resonant circuit, the switch circuit 1 and the negative resistance active circuit; when the second voltage-controlled oscillation unit works, the switch MOS tube M3 is turned on and M4 is turned off, at this time, the voltage-controlled oscillator outputs the signal of the intermediate frequency band, and the frequency range of the output signal is 37GHz~43.5GHz; The third voltage-controlled oscillation unit is composed of the resonant circuit, the switch circuit 1, the switch circuit 2 and the negative resistance active circuit; when the third voltage-controlled oscillation unit works, the switch MOS tubes M3 and M4 are both turned on, the resonant inductor L1, the switch coupling inductor L2 and L3 are connected in the circuit, at this time, the voltage-controlled oscillator outputs the signal of the low frequency band, and the frequency range of the output signal is 24.25GHz~27.5GHz.

2. The CMOS voltage-controlled oscillator applied to the anti-interference unmanned aerial vehicle millimeter wave radar according to claim 1, wherein: The overall bandwidth of the output frequency band of the voltage-controlled oscillator is divided into multiple sub-bandwidths by using the switch capacitor array, and the output frequency is continuously tuned in each sub-band by controlling the voltage difference between the two ends of the varactor.

3. The CMOS voltage controlled oscillator applied to the anti-interference unmanned millimeter wave radar according to claim 1, characterized in that: The resonant inductor L1, the switch coupling inductor L2 and the switch coupling inductor L3 are placed from inside to outside in sequence; The resonant inductor L1, the switch coupling inductor L2 and the switch coupling inductor L3 constitute a double-phase transformer structure, wherein the switch coupling inductors L2 and L3 are input windings, and the resonant inductor L1 is an output winding.

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