Broadband filtering 180° phase shifter, chip, and device based on magnetically coupled path switching

Abstract

This application provides a broadband filtering 180° phase shifter, chip, and device based on magnetically coupled path switching, including an RF input terminal, a magnetically coupled path switchable network, a matching network, and an RF output terminal. The magnetically coupled path switchable network includes a first inductor, second and third inductors forming positive and negative magnetic couplings with it respectively, and first and second transistors connected to the second and third inductors respectively. The matching network includes first and second series matching units and a parallel matching unit. By alternately controlling the transistors to be on and off, the phase shifter exhibits a consistent third-order bandpass response in both the reference state and the phase-shifted state: the first capacitor and the first inductor at the input terminal are connected in parallel to form a first resonator; the off transistor and the connected inductor form a second resonator; the on transistor grounds the corresponding series matching unit, forming a third resonator with the parallel matching unit, and another series matching unit provides inter-stage coupling. This application achieves broadband high-amplitude phase consistency, significantly improving phase-shifting accuracy.

Description

Technical Field

[0001] This application relates to the field of microwave and millimeter-wave integrated circuit technology, and in particular to a broadband filtering 180° phase shifter, chip and device based on magnetic coupling path switching. Background Technology

[0002] Phase shifters are key components for beamforming and scanning in modern phased array radar, satellite communications, and fifth-generation (5G) and even sixth-generation (6G) mobile communication systems. Among them, the 180° phase shifter, as the highest effective bit in a multi-phase shifter, is usually the largest source of amplitude and phase errors in the entire system. Its performance directly determines the beam pointing accuracy, sidelobe level, and system efficiency of the entire phased array system.

[0003] Existing on-chip integrated 180° phase shifters mainly adopt the following two structures, but both have obvious limitations in high-performance applications:

[0004] The first type is the high-pass / low-pass filter (HP / LP) structure. While this structure is simple in principle, it suffers from three major drawbacks when achieving a large 180° phase shift:

[0005] 1) Significant amplitude error. Due to the different topologies of the high-pass and low-pass paths, their loss mechanisms are fundamentally different (limited by the parasitic losses of parallel and series components, respectively). This asymmetry makes it difficult to keep the insertion loss of the two signals consistent across a wide bandwidth, thus introducing a large gain error.

[0006] 2) Large chip footprint. To achieve a large phase shift of 180° over a wide bandwidth while maintaining impedance matching, a high-order network containing multiple inductors is typically required. Due to the large size of on-chip inductors, the use of numerous inductors significantly increases chip area and manufacturing cost.

[0007] 3) Limited phase bandwidth. This structure relies on a steep phase slope near the filter cutoff frequency to generate a phase shift, making the phase frequency characteristics extremely sensitive to frequency and difficult to maintain a constant 180° phase difference over a wide bandwidth.

[0008] The second type is the differential switching structure based on a balun. This structure uses a balun to convert a single-ended signal into a differential signal and achieves a 180° phase shift by changing the current direction through a switching network. While it has good theoretical consistency, it faces significant challenges in the millimeter-wave frequency band.

[0009] 1) Phase bandwidth is limited. The overall bandwidth of the phase shifter is directly limited by the frequency characteristics of the balun component.

[0010] 2) Extremely sensitive to high-frequency parasitic parameters. In the millimeter-wave band, the circuit size is comparable to the signal wavelength, making this structure highly sensitive to the physical symmetry of the layout, process variations, and parasitic effects. Even minor structural asymmetries or differences in parasitic parameters can lead to significant amplitude and phase errors.

[0011] In summary, existing technologies struggle to simultaneously meet the demands for high amplitude and phase consistency, low insertion loss, and miniaturization across a wide bandwidth. Therefore, an innovative circuit architecture is urgently needed to achieve stable and precise 180° phase shifts over a wide bandwidth, while also possessing the advantages of low loss and small size. Summary of the Invention

[0012] The main objective of this application is to propose a broadband filtering 180° phase shifter, chip, and device based on magnetically coupled path switching. This phase shifter aims to solve the problems of limited bandwidth, large amplitude and phase errors, and significant chip area in existing technologies when achieving a large 180° phase shift value.

[0013] To achieve the above objectives, in a first aspect, one embodiment of this application proposes a broadband filtering 180° phase shifter based on magnetically coupled path switching, comprising:

[0014] RF input terminal P1 and RF output terminal P2;

[0015] First control voltage terminal K1 and second control voltage terminal K2;

[0016] A magnetically coupled path switchable network has its input terminal connected to the radio frequency input terminal P1;

[0017] A matching network is connected between the magnetically coupled path switchable network and the RF output terminal P2;

[0018] The magnetically coupled path switchable network includes:

[0019] The first inductor L1 has its first end connected to the radio frequency input terminal P1 and its second end grounded.

[0020] The second inductor L2a and the third inductor L2b are both magnetically coupled to the first inductor L1, and the magnetic coupling polarity between the second inductor L2a and the first inductor L1 is opposite to that between the third inductor L2b and the first inductor L1.

[0021] The first transistor M1 has its first conducting terminal connected to the non-grounded terminal of the second inductor L2a, its second conducting terminal grounded, and its control terminal connected to the first control voltage terminal K1.

[0022] The second transistor M2 has its first conducting terminal connected to the non-grounded terminal of the third inductor L2b, its second conducting terminal grounded, and its control terminal connected to the second control voltage terminal K2.

[0023] The first control voltage terminal K1 and the second control voltage terminal K2 are configured to receive complementary control signals, such that the first transistor M1 and the second transistor M2 are in complementary on and off states, thereby selectively selecting the positive magnetic coupling path constructed by the first inductor L1 and the second inductor L2a, or the negative magnetic coupling path constructed by the first inductor L1 and the third inductor L2b, and transmitting the signal to the RF output terminal P2 through the matching network, thereby realizing the switching of the signal transmission path between magnetic coupling paths of different polarities.

[0024] More importantly, thanks to the symmetrical design of the circuit, this application achieves a third-order bandpass filter response with completely consistent amplitude and phase characteristics in both switching states by multiplexing transistor parasitic parameters and combining them with a matching network.

[0025] 1) First resonator: The first capacitor and the first inductor at the RF input terminal constitute the first resonator;

[0026] 2) Second resonator: A transistor in the off state resonates with the second or third inductor of its branch using its parasitic capacitance, forming a second resonator;

[0027] 3) Third resonator: The transistor in the on state, together with the third or second inductor of the branch and some components in the matching network, tune together to form a third resonator;

[0028] 4) Interstage coupling: The matching network is also configured to provide interstage coupling between the second resonator and the third resonator.

[0029] In some embodiments, the phase shifter has structural symmetry to ensure consistency of amplitude and phase characteristics in the reference state and the phase-shifted state. The structural symmetry includes: the first transistor M1 and the second transistor M2 have the same size and electrical characteristics; the second inductor L2a and the third inductor L2b have the same inductance value and geometry; the magnetic coupling coefficient between the first inductor L1 and the second inductor L2a is equal to the magnetic coupling coefficient between the first inductor L1 and the third inductor L2b; the matching network has a symmetrical structure, and the matching units connected to the positive magnetic coupling path and the matching units connected to the negative magnetic coupling path have the same parameter values.

[0030] In some embodiments, a first capacitor C1 is further included between the RF input terminal P1 and ground; the phase shifter is configured to exhibit a completely consistent third-order bandpass filter response in both the reference state and the phase-shifted state by using a multiplexed transistor parasitic parameter coordinated matching network: the first capacitor C1 and the first inductor L1 constitute a first resonator; the transistor in the off state resonates with the second inductor L2a or the third inductor L2b connected to its first conducting terminal using its parasitic capacitance to form a second resonator; the transistor in the conducting state grounds the series matching unit connected to its first conducting terminal through its on-resistance and resonates with the parallel matching unit in the matching network to form a third resonator; and the matching network is also configured to provide interstage coupling between the second resonator and the third resonator.

[0031] In some embodiments, the matching network includes a first series matching unit A, a second series matching unit B, and a parallel matching unit C;

[0032] The first series matching unit A is connected between the first conducting terminal of the first transistor M1 and the radio frequency output terminal P2;

[0033] The second series matching unit B is connected between the first conducting terminal of the second transistor M2 and the radio frequency output terminal P2;

[0034] The other ends of the first series matching unit A and the second series matching unit B are both connected to the radio frequency output terminal P2;

[0035] The parallel matching unit C is connected between the RF output terminal P2 and ground.

[0036] In some embodiments, the matching network is a first-type structure, wherein:

[0037] Both the first series matching unit A and the second series matching unit B are capacitors with equal capacitance values;

[0038] The parallel matching unit C is an inductor;

[0039] The first type of structure is configured to construct the third resonator and provide magnetoelectric coupling between the second resonator and the third resonator.

[0040] In some embodiments, the matching network is a second type of structure, wherein:

[0041] Both the first series matching unit A and the second series matching unit B are inductors with equal inductance values;

[0042] The third parallel matching unit C is a capacitor;

[0043] The second type of structure is configured to construct the third resonator and provide electromagnetic coupling between the second resonator and the third resonator.

[0044] In some embodiments, two matching network topologies are provided:

[0045] Type I structure: Both the first series matching unit A and the second series matching unit B are capacitors, and the parallel matching unit C is an inductor. This structure utilizes either the first or second series matching unit to provide interstage coupling.

[0046] Type II structure: Both the first series matching unit A and the second series matching unit B are inductors, and the parallel matching unit C is a capacitor. This structure utilizes either the first or second series matching unit to provide interstage coupling.

[0047] In some embodiments, a first capacitor C1 is further included, which is connected in parallel with the first inductor L1 between the radio frequency input terminal P1 and ground.

[0048] Secondly, another aspect of the embodiments of this application proposes a monolithic microwave integrated circuit chip, including the broadband filter-type 180° phase shifter as described in the first aspect above.

[0049] In some embodiments, the chip is manufactured using gallium arsenide (GaAs), complementary metal-oxide-semiconductor (CMOS), silicon-germanium (SiGe), or other suitable semiconductor processes.

[0050] Thirdly, embodiments of this application provide a communication device, including a monolithic microwave integrated circuit chip as described in the second aspect above, or including a broadband filtering 180° phase shifter as described in the first aspect above. The communication device includes, but is not limited to, a phased array radar system, a satellite communication terminal, or a broadband wireless communication base station.

[0051] The beneficial effects of this application include:

[0052] 1) Wideband High-Precision Amplitude and Phase Consistency: Addressing the common challenge of simultaneously achieving high-precision amplitude and phase consistency and compact size across a wide bandwidth in existing technologies, this application innovatively employs a switchable magnetically coupled path network based on a symmetrical topology. By selectively switching between positive and negative magnetically coupled paths, a 180° phase flip is naturally generated; and since the reference state and phase-shifted state are configured with substantially consistent circuit parameters and transmission characteristics, parasitic errors are effectively eliminated, achieving extremely low phase and gain errors across a wide bandwidth.

[0053] 2) Integrated Filtering and Phase Shifting Functions (Miniaturization): This application innovatively utilizes a "parasitic parameter reuse" mechanism, breaking the limitation of traditional phase shifters requiring cascaded additional filter circuits. By reused the parasitic capacitance (Coff) of the cutoff transistor as a resonant element, and reused the on-resistance (Ron) of the on-transistor in conjunction with a matching network to construct a resonator, a highly consistent third-order bandpass filter response is achieved in both states. This mechanism significantly reduces the number of on-chip inductors, substantially reduces chip area, and lowers manufacturing costs.

[0054] 3) Flexible frequency response control: This application provides two matching topologies, Type I (electrically coupled, enhanced low-frequency suppression) and Type II (magnetically coupled, enhanced high-frequency suppression), which can flexibly select enhanced low-frequency suppression or high-frequency suppression according to the out-of-band suppression requirements of specific application scenarios, thereby improving the applicability of the phase shifter in complex electromagnetic environments.

[0055] 4) Excellent process compatibility and scalability: The circuit architecture is insensitive to process technology and can be easily migrated to various integrated circuit processes such as CMOS, GaAs, and SiGe. By scaling the values ​​of passive components proportionally, this solution is applicable to a wide range of applications from the X-band to the W-band and even higher frequency bands. Attached Figure Description

[0056] Figure 1 A schematic diagram of the general circuit topology of a broadband filter-type 180° phase shifter based on magnetic coupling path switching provided in the embodiments of this application.

[0057] Figure 2 This is a schematic diagram of a specific circuit based on the first type of matching network structure (Type I, capacitive coupling type) in Embodiment 1 of this application.

[0058] Figure 3 For the corresponding Figure 2 The simulation diagram of the amplitude response of the scattering parameters (S21) and the distribution of the transmission poles of the phase shifter in the reference state and the phase-shifted state of the embodiment.

[0059] Figure 4 This is a schematic diagram of a specific circuit based on the second type of matching network structure (Type II, inductive coupling) in Embodiment 2 of this application.

[0060] Figure 5 For the corresponding Figure 4 A simulation diagram of the amplitude response of the scattering parameters (S21) of the phase shifter in the embodiment under the reference state and the phase-shifted state.

[0061] Explanation of the labels in the diagram:

[0062] P1, RF input terminal; P2, RF output terminal;

[0063] K1, First control voltage terminal (corresponding to the gate of transistor M1); K2, Second control voltage terminal (corresponding to the gate of transistor M2);

[0064] M1, the first transistor; M2, the second transistor;

[0065] C1, the first capacitor; L1, the first inductor;

[0066] L2a, the second inductor; L2b, the third inductor;

[0067] A. First series matching unit; B. Second series matching unit; C. Parallel matching unit;

[0068] Cma, first matching capacitor; Cmb, second matching capacitor; Lg, common inductor;

[0069] Lma, first matching inductor; Lmb, second matching inductor; Cg, common capacitor. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0071] 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 belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0072] like Figure 1 As shown in the figure, this application provides a broadband filtering 180° phase shifter based on magnetic coupling path switching. The phase shifter mainly includes: an RF input terminal P1, an RF output terminal P2, a magnetic coupling path switchable network, and a matching network.

[0073] The overall connection of the circuit is as follows: the RF input terminal P1 is connected to one end of the first capacitor C1 and one end of the first inductor L1; the other ends of the first capacitor C1 and the first inductor L1 are both connected to ground (i.e., C1 and L1 are connected to ground in parallel, forming the first resonator). The magnetic coupling path switchable network includes the first inductor L1 located on the input side, and the second inductor L2a and the third inductor L2b located on the output side. The first inductor L1 generates mutual inductive coupling with the second inductor L2a and the third inductor L2b, respectively. In particular, L2a and L1 are positively (same-name terminals) magnetically coupled, and L2b and L1 are negatively (opposite-name terminals) magnetically coupled, thereby inducing mutually opposite signal components in L2a and L2b. One end of the second inductor L2a is connected to ground, and the other end is connected to the first conducting terminal (drain) of the first transistor M1 and one end of the first series matching unit A in the matching network. One end of the third inductor L2b is connected to ground, and the other end is connected to the first conducting terminal (drain) of the second transistor M2 and one end of the second series matching unit B in the matching network. The second conducting terminal (source) of the first transistor M1 and the second conducting terminal (source) of the second transistor M2 are both connected to ground; the control terminal (gate) of the first transistor M1 is connected to the first control voltage terminal K1, and the control terminal (gate) of the second transistor M2 is connected to the second control voltage terminal K2. The other end of the first series matching unit A and the other end of the second series matching unit B in the matching network converge at a common node and are connected to the RF output terminal P2. One end of the parallel matching unit C in the matching network is connected to the RF output terminal P2, and the other end is connected to ground.

[0074] The magnetically coupled path switchable network utilizes transistors (M1 / M2) in complementary switching states to alternately select the positive or negative magnetic coupling path, achieving a 180° phase shift. More importantly, this structure constructs a third-order bandpass filter response by reusing the parasitic capacitance (Coff) of the cutoff transistor and the on-resistance (Ron) of the on-transmitter, in conjunction with the matching network.

[0075] Depending on the specific component types of units A, B, and C, the matching network can be configured with different filtering topologies. This application embodiment mainly demonstrates (but is not limited to) the following two preferred forms:

[0076] 1) Type I structure (capacitive coupling type): Series matching units A and B use capacitors (Cma, Cmb), and parallel matching unit C uses an inductor (Lg).

[0077] 2) Type II structure (inductive coupling type): Series matching units A and B use inductive elements (Lma, Lmb), and parallel matching unit C uses capacitive elements (Cg).

[0078] Example 1: A wideband 180° phase shifter based on a Type I structure (capacitively coupled)

[0079] like Figure 2 As shown, this embodiment... Figure 1 The matching network in the design is specifically designed, using a first-type matching topology (Type I):

[0080] • The first series matching unit A is specifically the first matching capacitor Cma;

[0081] • The second series matching unit B is specifically the second matching capacitor Cmb;

[0082] • The parallel matching unit C is specifically the common inductor Lg.

[0083] The specific circuit connection is as follows:

[0084] A first capacitor C1 and a first inductor L1 are connected in parallel between the RF input terminal P1 and ground, forming a first resonator. The first inductor L1 serves as the input coil of the magnetically coupled structure, used to receive RF signals. The magnetically coupled path switchable network includes a second inductor L2a with positive magnetic coupling to the first inductor L1 and a third inductor L2b with negative magnetic coupling. One end of the second inductor L2a is directly grounded, and its other end is connected to the first conducting terminal of the first transistor M1 and one end of the first matching capacitor Cma. One end of the third inductor L2b is directly grounded, and its other end is connected to the first conducting terminal of the second transistor M2 and one end of the second matching capacitor Cmb. The second conducting terminals of both the first transistor M1 and the second conducting terminal of the second transistor M2 are connected to ground. The control terminal of the first transistor M1 is connected to the first control voltage terminal K1, and the control terminal of the second transistor M2 is connected to the second control voltage terminal K2. In the output matching stage, the other ends of the first matching capacitor Cma and the second matching capacitor Cmb are combined and connected to the RF output terminal P2, and a common inductor Lg is connected in parallel between the RF output terminal P2 and ground.

[0085] Working principle and parasitic parameter reuse mechanism:

[0086] This embodiment utilizes the symmetry of the circuit to construct a third-order bandpass filter response with completely consistent physical mechanism in two states by controlling the conduction and cutoff of the transistor. The specific working process is as follows:

[0087] 1) Reference State: Selects the negative magnetic coupling path.

[0088] When the first control voltage K1 is high and the second control voltage K2 is low, the first transistor M1 is in the on state and the second transistor M2 is in the off state.

[0089] Transistor characteristics and path selection: The first conducting transistor M1 exhibits low impedance (on-resistance Ron), pulling the node connected to the second inductor L2a low to ground, thereby bypassing and blocking the positive magnetic coupling path. The second cut-off transistor M2 exhibits high impedance (parasitic capacitance Coff), causing the signal to be transmitted mainly through the negative magnetic coupling path between the first inductor L1 and the third inductor L2b, and coupled to the output terminal P2 through the second matching capacitor Cmb.

[0090] Construction of a third-order resonator (parasitic parameter reuse):

[0091] First resonator: The first capacitor C1 and the first inductor L1 of the RF input terminal P1 are connected in parallel to form the input stage resonator;

[0092] Second resonator: The parasitic capacitance Coff of the cut-off second transistor M2 resonates in parallel with the third inductor L2b in the same branch, forming an intermediate stage resonator.

[0093] The third resonator: The first transistor M1, which is turned on, utilizes its low-impedance characteristic (Ron) to ground one end of the first matching capacitor Cma connected to its first conducting terminal. At this time, the first matching capacitor Cma is reused as a grounding capacitor connected in parallel to the RF output terminal P2. It is tuned together with the common inductor Lg to form the output stage resonator.

[0094] In this state, the second matching capacitor Cmb acts as an interstage coupling element between the second and third resonators.

[0095] 2) Phase-Shifting State: Selects the forward magnetic coupling path.

[0096] When the first control voltage terminal K1 is at a low level and the second control voltage terminal K2 is at a high level, the first transistor M1 switches to the off state and the second transistor M2 switches to the on state.

[0097] Transistor characteristics and path selection: The first transistor M1 presents a parasitic capacitance Coff, and the second transistor M2 presents an on-resistance Ron. The conducting second transistor M2 pulls the non-grounded terminal of the third inductor L2b low to ground, thereby blocking the negative magnetic coupling path. The RF signal path switches to the positive magnetic coupling path formed by the first inductor L1 and the second inductor L2a, and is transmitted to the RF output terminal P2 through the first matching capacitor Cma.

[0098] Phase flipping mechanism: Since the second inductor L2a (positive coupling) and the third inductor L2b (negative coupling) have opposite magnetic coupling polarities relative to the first inductor L1, and the circuit structure is highly symmetrical, the output signal naturally undergoes a 180° phase flip after switching paths.

[0099] Reconstruction of the resonator: At this point, the circuit utilizes symmetry to reconstruct a third-order filter response consistent with the reference state.

[0100] First resonator: The first capacitor C1 and the first inductor L1 of the RF input terminal P1 are connected in parallel to form the input stage resonator;

[0101] Second resonator: The parasitic capacitance Coff of the cut-off first transistor M1 and the second inductor L2a form the second resonator;

[0102] Third resonator: The conducting second transistor M2 connects one end of the second matching capacitor Cmb connected to its first conducting terminal to ground, so that it is reused as a parallel resonant element at the output terminal, and together with the common inductor Lg, forms the third resonator.

[0103] In this state, the first matching capacitor Cma acts as an interstage coupling element between the second and third resonators.

[0104] 3) Simulation result verification

[0105] Figure 3 The simulation curves of amplitude and phase response based on the Type I structure provided in Embodiment 1 of this application are shown. Figure 3 As shown, the phase shifter exhibits a consistent third-order bandpass filter response (S21) in both the reference state (Ref, solid line) and the phase-shifted state (Shift, dashed line). Simulation data shows that the phase error is controlled within 180° within the operating frequency band. ±0.8 Within this range, the gain error (GE) is less than 0.07 dB, verifying the excellent amplitude and phase consistency of this embodiment over the wide bandwidth.

[0106] Example 2: A wideband 180° phase shifter based on a Type II structure (inductively coupled)

[0107] like Figure 4 As shown, this embodiment... Figure 1 The matching network in the paper is further concretized in another form, namely, by adopting a Type II matching structure:

[0108] • The first series matching unit A is specifically the first matching inductor Lma;

[0109] • The second series matching unit B is specifically the second matching inductor Lmb;

[0110] • The parallel matching unit C is specifically the common capacitor Cg.

[0111] The specific circuit connection is as follows:

[0112] A first capacitor C1 and a first inductor L1 are connected in parallel between the RF input terminal P1 and ground. The first inductor L1 serves as the input coil of the magnetically coupled structure. The magnetically coupled path switchable network includes a second inductor L2a with positive magnetic coupling to the first inductor L1 and a third inductor L2b with negative magnetic coupling. One end of the second inductor L2a is directly grounded, and its other end is connected to the first conducting terminal of the first transistor M1 and one end of the first matching inductor Lma. One end of the third inductor L2b is directly grounded, and its other end is connected to the first conducting terminal of the second transistor M2 and one end of the second matching inductor Lmb. In the output matching stage, the other ends of the first matching inductor Lma and the second matching inductor Lmb are combined and connected to the RF output terminal P2, and a common capacitor Cg is connected in parallel between the RF output terminal P2 and ground.

[0113] Working principle and parasitic parameter reuse mechanism:

[0114] This embodiment utilizes the symmetry of the circuit to construct a third-order bandpass filter response with completely consistent physical mechanisms in both the reference state and the phase-shifted state by controlling the conduction and cutoff of the transistor. Unlike the Type I structure, this embodiment uses an inductor as a series matching unit and a capacitor as a parallel matching unit, forming an interstage coupling mode dominated by magnetic coupling.

[0115] 1) Reference State: Selects the negative magnetic coupling path.

[0116] When the first control voltage terminal K1 is at a high level and the second control voltage terminal K2 is at a low level, the first transistor M1 is turned on and the second transistor M2 is turned off.

[0117] Transistor Characteristics and Path Selection: The first conducting transistor M1 utilizes its low-impedance characteristic to ground one end of the first matching inductor Lma connected to its first conducting terminal, making it multiplexed as a ground inductor connected in parallel to the RF output terminal P2. At this time, the parasitic capacitance of the second transistor M2, which is turned off, resonates with the third inductor L2b in the same branch, and the signal is transmitted through the third inductor L2b and the second matching inductor Lmb, which is a series element.

[0118] Construction of a third-order resonator (parasitic parameter reuse):

[0119] First resonator: The first capacitor C1 and the first inductor L1 are connected in parallel and resonate to form the input stage resonator.

[0120] Second resonator: The parasitic capacitance Coff of the cut-off second transistor M2 resonates in parallel with the third inductor L2b, forming an intermediate stage resonator.

[0121] Third resonator: When M1 is turned on, one end of the first matching inductor Lma is grounded. Lma is reused as the parallel grounding inductor of the output terminal, and together with the common capacitor Cg, they are tuned to form the third resonator.

[0122] Interstage coupling: The second matching inductor Lmb acts as the interstage coupling element between the second and third resonators. This is magnetic coupling.

[0123] 2) Phase-Shifting State: Selects the forward magnetic coupling path.

[0124] When the first control voltage terminal K1 is at a low level and the second control voltage terminal K2 is at a high level, the first transistor M1 is turned off and the second transistor M2 is turned on.

[0125] Transistor Characteristics and Path Selection: The conducting second transistor M2 grounds the second matching inductor Lmb, multiplexing it as a parallel inductor. The parasitic capacitance of the cut-off first transistor M1 resonates with the second inductor L2a. The signal is transmitted via the second inductor L2a and the first matching inductor Lma, which is a series element. Unlike the Type I structure, this structure uses a matching network in the form of a series inductor and a parallel capacitor, resulting in a steeper stopband attenuation characteristic at high frequencies.

[0126] Construction of a third-order resonator (parasitic parameter reuse):

[0127] First resonator: The first capacitor C1 and the first inductor L1 of the RF input terminal P1 are connected in parallel to form the input stage resonator.

[0128] Second resonator: The parasitic capacitance Coff of the cut-off first transistor M1 resonates in parallel with the second inductor L2a.

[0129] Third resonator: When M2 is turned on, one end of the second matching inductor Lmb is grounded. Lmb is reused as the parallel grounding inductor of the output terminal, and together with the common capacitor Cg, they form the third resonator.

[0130] Interstage coupling: The first matching inductor Lma acts as the interstage coupling element between the second and third resonators. This is magnetic coupling.

[0131] 4) Simulation result verification: Figure 5 The simulation curves of amplitude and phase response based on the Type II structure provided in Embodiment 2 of this application are shown. Figure 5 As shown, the Type II structure also achieves excellent broadband performance. Simulation results show that its phase error is approximately 179.1 ± 0.8 dB, and its gain error (GE) is less than 0.16 dB. Furthermore, the S21 curve of this structure exhibits a faster roll-off in the high-frequency range, demonstrating its superior high-frequency harmonic suppression capability.

[0132] It should be noted that the circuit architecture proposed in this application has good frequency portability. Although the above embodiments mainly demonstrate performance in the Ka band (approximately 20-35 GHz), the technical solution of this application is not limited to this frequency band. By scaling the parameter values ​​of inductors and capacitors proportionally, the circuit structure of this application can be easily migrated to other frequency bands (such as X band, Ku band, V band, or W band, etc.) while maintaining the same wideband 180° phase shift characteristics, low loss, and compact chip size.

[0133] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0134] The terms "first," "second," "third," "fourth," etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0135] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A broadband filtering 180° phase shifter based on magnetically coupled path switching, characterized in that, include: RF input terminal (P1) and RF output terminal (P2); First control voltage terminal (K1) and second control voltage terminal (K2); A magnetically coupled path switchable network has its input connected to the radio frequency input (P1). A matching network is connected between the magnetically coupled path switchable network and the radio frequency output (P2); The magnetically coupled path switchable network includes: The first inductor (L1) has its first end connected to the radio frequency input terminal (P1) and its second end grounded; The second inductor (L2a) and the third inductor (L2b) are both magnetically coupled to the first inductor (L1), and the magnetic coupling polarity between the second inductor (L2a) and the first inductor (L1) is opposite to that between the third inductor (L2b) and the first inductor (L1). The first transistor (M1) has its first conducting terminal connected to the non-grounded terminal of the second inductor (L2a), its second conducting terminal grounded, and its control terminal connected to the first control voltage terminal (K1). The second transistor (M2) has its first conducting terminal connected to the non-grounded terminal of the third inductor (L2b), its second conducting terminal grounded, and its control terminal connected to the second control voltage terminal (K2). The matching network is connected to the first conducting terminal of the first transistor (M1), the first conducting terminal of the second transistor (M2), and the radio frequency output terminal (P2), respectively. The first control voltage terminal (K1) and the second control voltage terminal (K2) are configured to receive complementary control signals, such that the first transistor (M1) and the second transistor (M2) are in complementary on and off states, thereby selectively selecting the positive magnetic coupling path constructed by the first inductor (L1) and the second inductor (L2a), or the negative magnetic coupling path constructed by the first inductor (L1) and the third inductor (L2b), and transmitting the signal to the RF output terminal (P2) through the matching network, thereby realizing the switching of the signal transmission path between magnetic coupling paths of different polarities.

2. The broadband filtering 180° phase shifter according to claim 1, characterized in that, The phase shifter has structural symmetry to ensure the consistency of its amplitude and phase characteristics in the reference state and the phase-shifted state. The structural symmetry includes: the first transistor (M1) and the second transistor (M2) have the same size and electrical characteristics; the second inductor (L2a) and the third inductor (L2b) have the same inductance value and geometry; the magnetic coupling coefficient between the first inductor (L1) and the second inductor (L2a) is equal in magnitude to the magnetic coupling coefficient between the first inductor (L1) and the third inductor (L2b); the matching network has a symmetrical structure, and the matching units connected to the positive magnetic coupling path and the matching units connected to the negative magnetic coupling path have the same parameter values.

3. The broadband filtering 180° phase shifter according to claim 1, characterized in that, It also includes a first capacitor (C1) connected between the RF input terminal (P1) and ground; the phase shifter is configured to exhibit a completely consistent third-order bandpass filter response in both the reference state and the phase-shifted state by using a matching network with multiplexed transistor parasitic parameters: the first capacitor (C1) and the first inductor (L1) constitute a first resonator; the transistor in the off state resonates with the second inductor (L2a) or the third inductor (L2b) connected to its first conducting terminal using its parasitic capacitance to form a second resonator; the transistor in the conducting state grounds the series matching unit connected to its first conducting terminal through its on-resistance and resonates with the parallel matching unit in the matching network to form a third resonator; and the matching network is also configured to provide interstage coupling between the second resonator and the third resonator.

4. The broadband filtering 180° phase shifter according to claim 3, characterized in that, The matching network includes a first series matching unit (A), a second series matching unit (B), and a parallel matching unit (C). The first series matching unit (A) is connected between the first conducting terminal of the first transistor (M1) and the radio frequency output terminal (P2); The second series matching unit (B) is connected between the first conducting terminal of the second transistor (M2) and the radio frequency output terminal (P2); The other ends of the first series matching unit (A) and the second series matching unit (B) are connected to the radio frequency output terminal (P2). The parallel matching unit (C) is connected between the RF output terminal (P2) and ground.

5. The broadband filtering 180° phase shifter according to claim 4, characterized in that, The matching network is a first-class structure, wherein: Both the first series matching unit (A) and the second series matching unit (B) are capacitors with equal capacitance values; The parallel matching unit (C) is an inductor; The first type of structure is configured to construct the third resonator and provide electrical coupling between the second resonator and the third resonator.

6. The broadband filtering 180° phase shifter according to claim 4, characterized in that, The matching network is a second type of structure, wherein: Both the first series matching unit (A) and the second series matching unit (B) are inductors with equal inductance values; The parallel matching unit (C) is a capacitor; The second type of structure is configured to construct the third resonator and provide magnetic coupling between the second resonator and the third resonator.

7. The broadband filtering 180° phase shifter according to any one of claims 1 to 6, characterized in that, Corresponding to the two complementary conduction states of the first transistor (M1) and the second transistor (M2), the phase shifter is configured to operate in the reference state and the phase-shifted state, respectively. In the reference state and the phase-shifted state, there is a 180° phase difference between the output signals of the phase shifter, and within the preset operating frequency band, both the reference state and the phase-shifted state exhibit a bandpass filter response with three transmission poles.

8. A monolithic microwave integrated circuit chip, characterized in that, Includes a broadband filter-type 180° phase shifter as described in any one of claims 1 to 7.

9. A communication device, characterized in that, It includes the monolithic microwave integrated circuit chip as described in claim 8, or the broadband filter-type 180° phase shifter as described in any one of claims 1 to 7; the communication device is a phased array radar system, a satellite communication terminal, or a broadband wireless communication base station.

Images