CN105552485A - Microwave phase shifter - Google Patents

Abstract

The invention discloses a phase shifter. The phase shifter is a novel circuit structure which realizes a phase shifting function by adopting a composite right and left handed transmission line unit structure. The phase shifter comprises an input stage amplifier, one or multiple composite right and left handed transmission line unit structures, and an output stage amplifier. The input stage amplifier matches an impedance at an input end with an impedance of each composite right and left handed transmission line unit structure and amplifies an signal; each right and left handed transmission line unit structure plays a role of signal phase shifting; and the output stage amplifier matches the impedance at the output end with the impedance of each composite right and left handed transmission line unit structure and amplifies the signal.

Description

A microwave phase shifter

technical field

The invention relates to the field of integrated circuits, in particular to a microwave phase shifter circuit

Background technique

Microwave phase shifter is a very common device in the field of microwave and millimeter wave, and has a wide range of applications in communication, radar, space positioning and other systems.

Common microwave phase shifters are mostly implemented with transmission line structures such as waveguides and microstrip lines. Usually, the structure is complex and the volume is large, so it is difficult to achieve intensification and miniaturization. Many restrictions.

Contents of the invention

The invention provides a phase shifter, which can realize a wide phase adjustment range, and can realize good gain consistency in each phase state.

A phase shifter proposed by the present invention includes an input stage amplifier, N composite left and right hand phase shifting units (N≥1), and an output stage amplifier. The input stage amplifier and the output stage amplifier provide signal amplification, the effect of input and output matching, and the input and output amplifier stages used compensate the loss of the phase shifting unit to the signal amplitude; the N composite left and right hand phase shifting units ( N≥1) to complete the signal phase adjustment function.

The composite left and right hand phase shifting unit is a phase shifting unit realized based on the composite left and right hand transmission line unit structure.

The composite left and right hand transmission line unit can realize the continuous change of positive phase shift, negative phase shift and zero phase shift in different frequency bands; by adjusting (tuning) the position of the zero phase shift frequency point of the composite left and right hand phase shifting unit, so that in the same frequency band The phase adjustment function of positive phase shift, negative phase shift and zero phase shift can be realized inside.

The composite left and right hand phase shifting unit includes a series resonator part (L _S -C _S ) and a parallel resonator part (L _P -C _P ).

The structure of the composite left-handed phase-shifting unit includes single-ended and differential serial-parallel-series (T-type) structures, serial-parallel or parallel-series (L-type) structures, parallel-series-parallel (π-type) )structure.

The adjustment (tuning) of the zero-phase-shift frequency point of the composite left-handed phase-shifting unit is accomplished by tuning one or more of the capacitive and inductive devices in the series resonator part and the parallel resonator part.

Further, the tuning of capacitive devices is based on variable capacitive devices, including varactor diodes, switched capacitor arrays, and digitally controlled artificial dielectric materials (DiCAD); the tuning of inductive devices is based on variable inductance devices, including adjustable inductance structures based on transformer coupling.

Description of drawings

Fig. 1 is a general structural block diagram of the phase shifter of the present invention.

Fig. 2 is an overall block diagram of the present invention in Fig. 1 and realizes the single-ended parallel-serial-parallel (π-type) structure of the composite left-handed phase-shifting unit.

Fig. 3(a) is the single-ended series-parallel (L-type) structure realization form of the compound left-handed phase-shifting unit in Fig. 1, which is an overall block diagram of the present invention.

Fig. 3(b) is the single-ended parallel-serial (L-type) structure realization form of the composite left-handed and left-handed phase-shifting unit in Fig. 1, the overall block diagram of the present invention.

Fig. 4 is an overall block diagram of the present invention in Fig. 1 and realizes the single-ended serial-parallel-serial (T-type) structure of the composite left-handed phase-shifting unit.

Fig. 5 is a schematic diagram of an embodiment of the principle of the present invention, wherein a differential Π-type composite left and right phase-shifting unit is used to realize, and the input stage and the output stage amplifier are realized by a differential form fixed gain amplifier. This embodiment tunes the zero phase shift frequency band position by tuning the capacitor in the parallel resonator. Among them, capacitors are implemented based on varactor diodes.

FIG. 6 is a simulation result of the variation of the S ₂₁ phase with frequency at different voltages of the varactor diode in the embodiment of the present invention.

FIG. 7 is a simulation result of the variation of the S parameter of the varactor diode with frequency under different voltages in the embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiment is only a possible implementation of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The invention provides a phase shifter, which can realize a wide phase adjustment range, and can realize good gain consistency in each phase state.

The overall structural block diagram of the present invention is as shown in Figure 1, including an input stage amplifier, N composite left and right hand phase shifting units, and an output stage amplifier. The input stage amplifier and the output stage amplifier provide signal amplification, input and output matching, and the input and output amplifier stages used to compensate the loss of signal amplitude by the passive phase shifting unit; the N composite left and right hand phase shifting The unit completes the signal phase adjustment function.

Referring to Fig. 2, it is the single-ended π-type network realization form of the composite hand-hand-hand phase-shifting unit in the present invention.

Referring to Fig. 3 (a) (b), it is the single-ended L-shaped network realization form of the composite hand-hand-right phase-shifting unit in the present invention.

Referring to FIG. 4 , it is a single-ended T-type network implementation form of the compound-hand-right-hand phase-shifting unit in the present invention.

The structure of an embodiment of the phase shifter of the present invention will be described in detail below in conjunction with FIGS. 5-6 .

In the embodiment of the present invention, referring to FIG. 5 , the input and output stage amplifiers adopt a differential structure and a constant gain amplifier structure, and are composed of transistors Q1, Q2, Q3, and Q4.

In the embodiment of the present invention, referring to FIG. 5 , the number of composite left and right hand phase shifting units is 1, and a differential serial-parallel-serial (π-type) structure is adopted to realize the form.

In an embodiment of the present invention, referring to FIG. 5 , the phase of the compound left-handed phase-shifting unit is realized by tuning the capacitive device in the series resonator structure. The tunable capacitive device is implemented based on the use of varactor diodes C _VAR1 , C _VAR2 , C _VAR3 , and C _VAR4 .

Referring to FIG. 6 , it is a simulation result of the phase shifter structure of the embodiment of the present invention. This embodiment is designed to work at a frequency of 38 GHz. Fig. 6 shows the variation of the phase of the phase shifter S21 under different control voltages of the varactor diode. Within the tuning range of the varactor diode, the adjustment range of the phase can reach 100 degrees.

Referring to FIG. 7 , it is a simulation result of the phase shifter structure of the embodiment of the present invention. This embodiment is designed to work at a frequency of 38 GHz. Figure 6 shows the amplitude values of the varactor diodes, S21 and port matching (S11 and S22) under different control voltages. Within the phase adjustment range of 100 degrees, the phase shifter in the embodiment can realize the amplitude floating range within 5dB , and keep the input and output ports matched.

Claims (10)

1. A microwave phase shifter, characterized in that the phase shifter includes: an input stage amplifier, a composite left and right hand phase shifter unit and an output stage amplifier. The input stage amplifier amplifies the input signal, and then inputs the signal to the composite left and right hand phase shifting unit, completes the phase adjustment of the signal through one or more stages of composite left and right hand phase shifting unit, and finally outputs the signal to the subsequent circuit through the output stage amplifier. 2. The microwave phase shifter according to claim 1, characterized in that the three parts of the input stage amplifier part, the composite left and right hand phase shifting unit part and the output stage amplifier part are cascaded. 3. microwave phase shifter according to claim 1, input stage amplifier and output stage amplifier can be single-ended amplifier, also can be differential amplifier, and input stage amplifier and output stage amplifier can be fixed gain amplifier, also can be variable gain amplifier. 4. The microwave phase shifter according to claim 1, wherein the number of composite left and right hand phase shifting units can be N (N≥1). 5. The microwave phase shifter according to claim 1, wherein the compound left-handed phase-shifting unit structure comprises series resonators (L _S -C _S ) and parallel resonators (L _P -C _P ). The structure of the composite left-handed phase-shifting unit includes single-ended and differential serial-parallel or parallel-serial (L-type) structures, parallel-serial-parallel (π-type) structures, and serial-parallel-serial (T-type) structures. 6. The capacitive device and the inductive device in the series resonant unit and the parallel resonant unit of the compound left and right hand unit according to claim 5 can be made of capacitance value fixed capacitive device and inductive device, also can be made of variable capacitive device and variable inductive device constitute. 7. The variable capacitance device according to claim 6, comprising a varactor diode, a switched capacitor array and a numerically controlled artificial dielectric material. 8. The variable inductance device according to claim 6, comprising a transformer-coupled tunable inductance structure. 9. The microwave phase shifter according to claim 1, the zero phase shift point of the composite left and right hand phase shifting unit is adjustable. 10. The composite left and right hand phase shifting unit according to claim 6, the adjustment of the phase can be realized by adjusting the variable capacitance device and (or) the variable inductance device.