CN115986344B

CN115986344B - Electrically-controlled differential phase shifter

Info

Publication number: CN115986344B
Application number: CN202310272557.XA
Authority: CN
Inventors: 杨实; 施金; 任建鹏
Original assignee: Novaco Microelectronics Technologies Ltd
Current assignee: Novaco Microelectronics Technologies Ltd
Priority date: 2023-03-21
Filing date: 2023-03-21
Publication date: 2023-06-23
Anticipated expiration: 2043-03-21
Also published as: CN115986344A

Abstract

The invention discloses an electrically-controlled differential phase shifter, which comprises a central symmetry line, a first circuit and a second circuit, wherein the first circuit and the second circuit respectively comprise a first capacitor, a first inductor, a second inductor and a second capacitor which are connected in series between the positive electrode and the negative electrode of a differential port; the positive electrode of the differential port is connected with a coupling inductor I and a coupling inductor II which are connected in series, an inductor III is connected in series between the coupling inductor I and a central symmetry line, a varactor I is connected in parallel between the inductor III and the coupling inductor I, an inductor IV is connected in series between the coupling inductor II and the central symmetry line, and a varactor II is connected in parallel between the inductor IV and the coupling inductor II; a capacitor six and a capacitor seven are connected in parallel between the coupling inductor I and the coupling inductor II, and a capacitor eight is connected between the capacitor six and the capacitor seven. The invention has the advantages of compact structure, small size and easy integration.

Description

Electrically-controlled differential phase shifter

Technical Field

The invention relates to the technical field of microwave communication, in particular to an electrically-tunable differential phase shifter.

Background

Phase shifters are an indispensable component in modern wireless communication systems, widely used in phased array antennas, phased array radars and beam steering systems for providing suitable phase shifts. The phase shifter is classified into a fixed value phase shifter and an electrically tunable phase shifter according to whether the phase can be electrically tunable. The phase shift provided by the fixed value phase shifter is a fixed value, cannot be adjusted in an actual use link, and structurally needs to be divided into a main line and a reference line; the phase of the electric tuning phase shifter can be electrically tuned by adding different voltages, so that different phase shifting values can be obtained in the practical use link conveniently, a main line and a reference line with different structures are not needed, and the communication system is more flexible, convenient and high-precision. The electrically-tunable differential phase shifter not only can obtain the advantages of the electrically-tunable phase shifter, but also can realize the phase shifting function of differential mode signals and the suppression function of common mode signals, and improves the compatibility of the phase shifter in a differential system and the immunity to environmental noise. However, the design of current electrically tunable differential phase shifters remains an important challenge.

The existing design methods of the electrically-tunable differential phase shifter are mainly two. The first method is to place the periodic stub on the upper surface of the substrate with the liquid crystal sandwiched in the middle, obtain different equivalent dielectric constants by changing the voltage received by the liquid crystal layer to realize differential mode adjustable phase shift, and realize common mode suppression by the dumbbell-shaped defect grounding structure at the lower layer, but the equivalent dielectric constant change phase shift has the problems of narrow bandwidth, large phase shift fluctuation in frequency bands, and the like, and has complex overall structure and process and large size. The second is an electrically-tunable differential phase shifter realized by integrating three branch line structures which are distributed in a central symmetry way on the basis of a differential port into a coupling line which is connected with a varactor, and the differential phase shifting of a broadband is realized through the stabilizing effect of the branch line structures and the coupling line on the integral differential phase shifting. The second method has a simplified structure compared with the first method, but the overall size is further increased, which is disadvantageous for miniaturization and integration.

Therefore, it is necessary to provide a novel electrically tunable differential phase shifter, which has the characteristics of compact structure and compact form, is convenient for miniaturization and integration, maintains wideband operation characteristics in performance, and maintains stable phase shift slope and good common mode rejection level in frequency bands.

Disclosure of Invention

Aiming at the problems in the related art, the invention provides an electrically-tunable differential phase shifter, which has the characteristics of compact structure and compact form, is convenient for miniaturization and integration, keeps the broadband working characteristic in performance, keeps stable phase shifting slope in a frequency band and has better common mode rejection level.

The technical scheme of the invention is realized as follows:

an electrically-controlled differential phase shifter comprises a central symmetry line, a first circuit and a second circuit which are symmetrically connected to two sides of the central symmetry line, wherein the first circuit and the second circuit respectively comprise a first capacitor, a first inductor, a second inductor and a second capacitor which are connected in series between the positive electrode and the negative electrode of a differential port, a third capacitor is connected in parallel between the first capacitor and the first inductor, a fourth capacitor is connected in parallel between the first inductor and the second inductor, and a fifth capacitor is connected in parallel between the second inductor and the second capacitor; the positive electrode of the differential port is connected with a first coupling inductor and a second coupling inductor which are connected in series, an inductance III is connected in series between the first coupling inductor and the central symmetry line, a first varactor is connected in parallel between the inductance III and the first coupling inductor, an inductance IV is connected in series between the second coupling inductor and the central symmetry line, and a second varactor is connected in parallel between the inductance IV and the second coupling inductor; and a capacitor six and a capacitor seven are connected in parallel between the coupling inductor I and the coupling inductor II, and a capacitor eight is connected between the capacitor six and the capacitor seven.

Wherein the inductance three of the first circuit is connected in series with the inductance three of the second circuit.

Wherein the inductance four of the first circuit is connected in series with the inductance four of the second circuit.

Wherein an inner side end of the coupling inductor of the first circuit and an inner side end of the coupling inductor of the second circuit are connected in series.

The second inner side end of the coupling inductor of the first circuit is connected with the second inner side end of the coupling inductor of the second circuit in series.

And a capacitor nine and a capacitor ten are respectively connected in parallel at the connection part of the inductor III and the connection part of the inductor IV on the central symmetry line.

Wherein, the central symmetry line is provided with a voltage bias point.

The differential ports comprise a first differential port and a second differential port, the first circuit is located on the first differential port side, and the second circuit is located on the second differential port side.

The beneficial effects are that:

the invention constructs the electrically-tunable differential phase shifter by loading the coupling inductance pairs of the parallel varactors, the parallel capacitors, the bridging capacitors, the capacitance and inductance alternately distributed in the differential ports and the like, and improves the degree of freedom of bandwidth design by utilizing the multiplexing adjustment effects of components on frequency, matching, phase shifting and common mode inhibition, has the advantage of stable phase shifting of broadband in performance, and has the advantages of compact structure, small size and easy integration by adopting lumped elements for realization of the integral structure.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of an electrically tunable differential phase shifter according to an embodiment of the present invention;

FIG. 2 is an |S of an electrically tunable differential phase shifter according to an embodiment of the present invention _dd11 The difference mimics the true response graph;

FIG. 3 is an |S of an electrically tunable differential phase shifter according to an embodiment of the present invention _dd21 The difference mimics the true response graph;

FIG. 4 is a graph of a co-simulated true response of an electrically tunable differential phase shifter according to an embodiment of the present invention;

fig. 5 is a phase shift simulation response diagram of an electrically tunable differential phase shifter according to an embodiment of the present invention.

In the figure:

1. a central symmetry line; 2. a first circuit; 3. a second circuit; 4. a first capacitor; 5. an inductance I; 6. an inductance II; 7. a second capacitor; 8. a third capacitor; 9. a fourth capacitor; 10. a fifth capacitor; 11. coupling an inductor I; 12. coupling an inductance II; 13. an inductance III; 14. a first varactor; 15. an inductance IV; 16. a second varactor; 17. a capacitor six; 18. a capacitor seven; 19. a capacitor eight; 20. a capacitor nine; 21. a capacitor ten; 22. voltage bias point.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which are derived by a person skilled in the art based on the embodiments of the invention, fall within the scope of protection of the invention.

According to an embodiment of the present invention, an electrically tunable differential phase shifter is provided.

As shown in fig. 1, an electrically tunable differential phase shifter according to an embodiment of the present invention includes a central symmetry line 1, a first circuit 2 and a second circuit 3 symmetrically connected to two sides of the central symmetry line 1, where the first circuit 2 and the second circuit 3 each include a first capacitor 4, a first inductor 5, a second inductor 6 and a second capacitor 7 connected in series between the positive and negative poles of a differential port, a third capacitor 8 is connected in parallel between the first capacitor 4 and the first inductor 5, a fourth capacitor 9 is connected in parallel between the first inductor 5 and the second inductor 6, and a fifth capacitor 10 is connected in parallel between the second inductor 6 and the second capacitor 7; the positive electrode of the differential port is connected with a first coupling inductor 11 and a second coupling inductor 12 which are connected in series, an inductance III 13 is connected in series between the first coupling inductor 11 and the central symmetry line 1, a first varactor 14 is connected in parallel between the inductance III 13 and the first coupling inductor 11, an inductance IV 15 is connected in series between the second coupling inductor 12 and the central symmetry line 1, and a second varactor 16 is connected in parallel between the inductance IV 15 and the second coupling inductor 12; a capacitor six 17 and a capacitor seven 18 are connected in parallel between the coupling inductor one 11 and the coupling inductor two 12, and a capacitor eight 19 is connected between the capacitor six 17 and the capacitor seven 18; the third inductor 13 of the first circuit 2 is connected in series with the third inductor 13 of the second circuit 3; the inductance four 15 of the first circuit 2 is connected in series with the inductance four 15 of the second circuit 3. The inner side end of the coupling inductor 11 of the first circuit 2 and the inner side end of the coupling inductor 11 of the second circuit 3 are connected in series; the inner side end of the second coupling inductor 12 of the first circuit 2 and the inner side end of the second coupling inductor 12 of the second circuit 3 are connected in series; the connection part of the third inductor 13 and the fourth inductor 15 on the central symmetry line 1 are respectively connected with a capacitor nine 20 and a capacitor ten 21 in parallel, and the central symmetry line 1 is provided with a voltage bias point 22.

In a specific application, the differential ports include a first differential port and a second differential port, the first circuit 2 is located at the first differential port side, and the second circuit 3 is located at the second differential port side.

When the electrically-controlled differential phase shifter works, differential mode signals are input from differential ports 1 (ports 1 & lt+ & gt and 1 & lt- & gt), fed into a first end-connected varactor 14, a second end-connected varactor 16, a first coupling inductor 11, a second coupling inductor 12, a sixth end-connected varactor 17, a seventh end-connected varactor 18 and an eighth end-connected varactor 19 after passing through a first capacitor 4, a first inductor 5, a second inductor 6, a second capacitor 7, a third capacitor 8, a fourth capacitor 9 and a fifth capacitor 10 among the differential ports 1, and are output from differential ports 2 (ports 2 & lt+ & gt and 2 & lt- & gt) after passing through the same symmetrical circuit on the right side, stable broadband differential mode phase shifting is formed under the action of an integral circuit and bias voltage, and certain common mode inhibition is achieved.

In the working process, the first coupling inductor 11 and the second coupling inductor 12 of the diagonally-loaded

parallel varactors

14 and 16 play a main role in the differential mode phase shift reference value of the phase shifter, the reference value changes along with the change of bias voltage, and the six 17, the seven 18 and the eight 19 connected in parallel can play an auxiliary role in adjusting the differential mode phase shift reference value. Meanwhile, the first coupling inductor 11, the second coupling inductor 12 and the first and second series-connected

inductors

5 and 6 between the differential ports play a main role in controlling the phase shift stability in the matching bandwidth, and are beneficial to forming broadband differential phase shift. The working frequency of the phase shifter is mainly controlled by a first coupling inductor 11, a second coupling inductor 12, a third capacitor 8, a fourth capacitor 9 and a fifth capacitor 10 which are connected in parallel between the self-inductance of the first coupling inductor and the differential port. The capacitance and inductance alternately distributed in the differential port contribute one reflection zero point, the coupling inductance I11, the coupling inductance II 12 and the parallel, bridging capacitance II 17, capacitance seven 18 and capacitance eight 19 contribute two reflection zero points, so that the broadband differential mode matching bandwidth is integrally realized. The capacitance and inductance distributed alternately in the differential port can feed in the differential signal of the broadband and form a certain inhibition effect on the common mode signal. The third inductor 13, the fourth inductor 15, the ninth capacitor 20 and the tenth capacitor 21 are used for controlling radio frequency signals and preventing the radio frequency signals from entering the direct current bias circuit to reduce the working performance of the phase shifter.

Therefore, the components of the phase shifter realize multiplexing in the aspects of matching bandwidth, phase shift reference value, stability, common mode inhibition and the like, and the degree of freedom of regulation and control of the design is improved, so that the advantage of stable broadband differential mode phase shift can be obtained. Meanwhile, the integrated circuit is realized through lumped parameter elements such as inductance, capacitance, coupling inductance and varactors, and has obvious advantages in the aspects of size and integration compared with distributed parameter design.

In order to facilitate understanding of the above technical solution of the present invention, the present invention is further described below by means of a simulation response case.

The differential mode response is shown in fig. 2-3, the common mode response is shown in fig. 4, and the phase shift response is shown in fig. 5. The device values of the circuit are respectively as follows: the capacitance values of the capacitor III 8, the capacitor V10 are 0.54pF, the capacitance value of the capacitor V9 is 1pF, the inductance value of the inductor I5 is 2.75nH, the inductance value of the inductor II 6 is 2.4nH, the self inductance value of the coupling inductor I11, the self inductance value of the coupling inductor II 12 is 0.99nH, the mutual inductance value is 0.72nH, the capacitance values of the capacitor V17 and the capacitor V18 are 0.39pF, the capacitance value of the capacitor V19 is 0.8pF, the inductance values of the capacitor V13 and the capacitor V15 are 270nH, the capacitance values of the capacitor V20, the capacitor V21, the capacitor V4 and the capacitor V7 are 430pF, and the variation range of the capacitance values Cv of the varactor I14 and the varactor V16 is 0.4 pF-1 pF. As can be seen from fig. 2-4, the capacitance Cv of the varactor is in the range of 0.4 pf-1 pf, the intersection range of the 10-dB matching bandwidths under different phase shift values is 3.16 GHz-5.26 GHz, that is, the relative bandwidth can reach 47.2%, and the 10dB common mode rejection frequency range is 2.7 GHz-5.52 GHz. The phase shift bandwidth measured within the range of 45 degrees+/-3 degrees is 3.29 GHz-5.26 GHz, namely the relative bandwidth can reach 44.3 percent; the phase shift bandwidth measured within the range of 90 DEG + -6 DEG is 3.21 GHz-5.29 GHz, namely the relative bandwidth can reach 46.7%.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.

Claims

1. The electric-tuning differential phase shifter comprises a central symmetry line, a first circuit and a second circuit which are symmetrically connected to two sides of the central symmetry line, and is characterized in that the first circuit and the second circuit comprise a first capacitor, a first inductor, a second inductor and a second capacitor which are connected in series between the positive electrode and the negative electrode of a differential port, a third capacitor is connected in parallel between the first capacitor and the first inductor, a fourth capacitor is connected in parallel between the first inductor and the second inductor, and a fifth capacitor is connected in parallel between the second inductor and the second capacitor; the positive electrode of the differential port is connected with a first coupling inductor and a second coupling inductor which are connected in series, an inductance III is connected in series between the first coupling inductor and the central symmetry line, a first varactor is connected in parallel between the inductance III and the first coupling inductor, an inductance IV is connected in series between the second coupling inductor and the central symmetry line, and a second varactor is connected in parallel between the inductance IV and the second coupling inductor; and a capacitor six and a capacitor seven are connected in parallel between the coupling inductor I and the coupling inductor II, and a capacitor eight is connected between the capacitor six and the capacitor seven.

2. The electrically tunable differential phase shifter of claim 1, wherein the inductance three of the first circuit is connected in series with the inductance three of the second circuit.

3. The electrically tunable differential phase shifter of claim 2, wherein the inductance four of the first circuit is connected in series with the inductance four of the second circuit.

4. The electrically tunable differential phase shifter of claim 3, wherein an inner side of the coupling inductance of the first circuit and an inner side of the coupling inductance of the second circuit are connected in series.

5. The electrically tunable differential phase shifter of claim 4, wherein the two inner ends of the coupling inductance of the first circuit and the two inner ends of the coupling inductance of the second circuit are connected in series.

6. The electrically tunable differential phase shifter according to claim 5, wherein a ninth capacitor and a tenth capacitor are connected in parallel to the junction of the third inductor and the fourth inductor, respectively, on the central symmetry line.

7. The electrically tunable differential phase shifter of claim 6, wherein the center symmetry line has a voltage bias point disposed thereon.

8. The electrically tunable differential phase shifter of any one of claims 1-7, wherein the differential ports comprise a first differential port and a second differential port, the first circuit being located on the first differential port side and the second circuit being located on the second differential port side.