WO2019085368A1

WO2019085368A1 - Wilkinson power divider

Info

Publication number: WO2019085368A1
Application number: PCT/CN2018/078914
Authority: WO
Inventors: 周海峰; 吴杰; 丁庆; 吴光胜; 李晓丛
Original assignee: 深圳市华讯方舟微电子科技有限公司; 华讯方舟科技有限公司
Priority date: 2017-10-31
Filing date: 2018-03-14
Publication date: 2019-05-09
Also published as: CN107946717A

Abstract

The present invention relates to a Wilkinson power divider, comprising a dielectric layer, a signal metal layer attached to one side of the dielectric layer, and a metal underlayer attached to the other side of the dielectric layer, wherein the signal metal layer, the dielectric layer and the metal underlayer form a microstrip line structure, and the signal metal layer comprises: microwave transmission branches for dividing one path of microwave signals into at least two paths of microwave branch signals; output ports for outputting the at least two paths of microwave branch signals, wherein the number of output ports matches the number of microwave transmission branches; and electromagnetic bandgap structures, wherein the electromagnetic bandgap structures are provided at positions of the output ports and are used for suppressing harmonics generated by the output signals of the power divider. Compared with a traditional Wilkinson power divider for carrying out out-of-band harmonic suppression by means of adding an additional harmonic suppression filter circuit, the Wilkinson power divider of the present invention effectively suppresses the higher harmonics of output signals, and greatly reduces the layout area of a circuit.

Description

Wilkinson Power Splitter

Technical field

The invention relates to the field of power dividers, and in particular to a Wilkinson power divider.

Background technique

At present, power dividers are widely used in the field of microwaves, such as power amplifiers, mixers, and frequency multipliers.

However, the traditional Wilkinson power splitter does not have the ability to suppress the out-of-band harmonics. In some practical applications, it is often necessary to add an additional harmonic suppression filter circuit for out-of-band harmonic suppression. The harmonic suppression filter is often constructed using a quarter-wavelength open microstrip line that operates at both ends of the center frequency, resulting in a large circuit area.

Summary of the invention

Based on this, it is necessary to provide a Wilkinson power divider for the problem that the Wilkinson power divider circuit with a harmonic suppression filter circuit has a large area.

A Wilkinson power divider comprising a dielectric layer, a signal metal layer attached to one side of the dielectric layer, and a metal underlayer attached to the other side of the dielectric layer, the signal metal layer, the dielectric layer, and the metal The underlayer forms a microstrip line structure, wherein the signal metal layer comprises:

Input port for inputting microwave signals;

a microwave transmission branch having at least two paths and connected to the input port, configured to divide the microwave signal into at least two microwave branch signals;

An output port, configured to output the at least two microwave branch signals, the number of the output ports is matched with the number of the microwave transmission branches, and each output port is respectively connected to one microwave transmission branch;

An electrical tape gap structure is disposed at the output port position for suppressing harmonics generated by the power splitter output signal.

In one embodiment, the electromagnetic bandgap structure is constructed by at least one of the following:

Attaching a metal patch arranged in a periodic pattern on the signal metal layer;

Forming grooves arranged in a periodic manner on the metal bottom layer;

A regular pattern arranged in a periodic pattern is engraved on the signal metal layer.

In one of these embodiments, each of the output port locations is provided with the electromagnetic bandgap structure.

In one embodiment, the method further includes an isolation resistor, and further includes an isolation resistor, and the isolation resistor is connected between the two adjacent output ports.

In one embodiment, the number of the microwave transmission branches is two, and the number of the output ports is two.

In one embodiment, the lengths of the two microwave transmission branches are equal, and the widths of the two microwave transmission branches are equal.

In one embodiment, the signal metal layer and the metal underlayer are made of copper.

In one embodiment, the dielectric layer is a RO4003C material having a dielectric constant of 3.55.

In one embodiment, the input port and the output port have a microstrip line structure impedance of 50 Ω.

In one of the embodiments, the isolation resistor has a resistance of 100 Ω.

The Wilkinson power splitter has an electromagnetic bandgap structure at the output port position compared with the conventional Wilkinson power splitter that adds an additional harmonic rejection filter circuit for out-of-band harmonic suppression. The Erjinsen power divider can effectively suppress the third harmonic and fifth harmonic of the output energy, while ensuring good insertion loss, isolation and echo index in the band. On the basis of effectively suppressing the higher harmonics of the output signal, the circuit layout area is greatly saved.

DRAWINGS

1 is a schematic structural view of a Wilkinson power divider according to an embodiment of the present invention;

2 is a waveform diagram of an input/output port reflection coefficient of a Wilkinson power divider according to an embodiment of the present invention;

3 is a waveform diagram of insertion loss of an output port of a Wilkinson power divider according to an embodiment of the present invention;

4 is a waveform diagram of isolation of an output port of a Wilkinson power divider according to an embodiment of the present invention;

5 is a waveform diagram showing reflection coefficients of an input port of an electromagnetic bandgap structure obtained by simulating an equivalent circuit of an electromagnetic bandgap structure according to an embodiment of the present invention;

6 is a waveform diagram showing insertion loss of an output port of an electromagnetic bandgap structure obtained by simulating an equivalent circuit of an electromagnetic bandgap structure according to an embodiment of the present invention.

Detailed ways

Referring to FIG. 1, FIG. 1 is a schematic structural diagram of a Wilkinson power divider in an embodiment.

In one embodiment of the invention, the Wilkinson power splitter includes a dielectric layer, a signal metal layer attached to one side of the dielectric layer, and a metal underlayer attached to the other side of the dielectric layer, signal metal The layer, the dielectric layer, and the metal underlayer form a microstrip line structure, and the signal metal layer includes an input port 10, a first shunt 11, a second shunt 12, and an isolation resistor 13.

The first branch 11 includes a first microwave transmission branch 111, a first electromagnetic bandgap structure 112, and a first output port 113.

The second branch 12 includes a second microwave transmission branch 121, a second electromagnetic bandgap structure 122, and a second output port 123.

The electrical tape gap structure is a periodic microwave structure with band resistance characteristics, slow wave characteristics, and high equivalent characteristic impedance characteristics, which can prevent electromagnetic waves from propagating in a certain direction or in all directions. A power splitter is a multi-port microwave network that splits the input signal power into equal or unequal power outputs. Power splitters are the most commonly used components in circuit systems. It can be used in antenna arrays or in microwave circuit design. The Wilkinson power splitter has become a common power splitter due to its simple circuit structure, low loss and good isolation.

The invention adds the electromagnetic band gap structure to the Wilkinson power divider circuit design, uses the band resistance characteristic to suppress the harmonic of the output signal of the Wilkinson power divider, and uses the slow wave characteristic to reduce the circuit size, and ensures the Wilkinson power splitter has the advantages of low insertion loss and high isolation.

In an embodiment of the present invention, the electromagnetic bandgap structure may be formed by attaching a periodic metal patch to the signal metal layer, forming a periodic groove on the metal underlayer or engraving on the signal metal layer. The method of making periodic rule graphics.

In an embodiment of the invention, the Wilkinson power splitter is a two-power splitter that splits the input signal energy of the input port into two energy outputs. In this embodiment, the Wilkinson power splitter has two microwave transmission branches and two output ports. In other embodiments, when the Wilkinson power splitter is a three-power splitter and a four-power splitter, the number of microwave transmission branches and output ports also changes, and the number of output ports and the microwave transmission branch road The numbers match.

In an embodiment of the invention, the Wilkinson power splitter is a halved Wilkinson power splitter that splits the input signal energy of the input port into two equal energy outputs. In this embodiment, the lengths of the first microwave transmission branch 111 and the second microwave transmission branch 121 are equal, and the widths of the first microwave transmission branch 111 and the second microwave transmission branch 121 are equal. In other embodiments, when the Wilkinson power splitter is an unequal power splitter, the length and width of the first microwave transmission branch 111 and the second microwave transmission branch 121 may be adjusted differently according to actual conditions. .

In one embodiment of the present invention, the first electromagnetic bandgap structure 112 is disposed at a position of the first output port 113, and the second electromagnetic bandgap structure 122 is disposed at a position of the second output port 123, using an electromagnetic bandgap structure The band-stop characteristic suppresses the harmonics of the output signal of the Wilkinson power divider. In the present embodiment, the electromagnetic bandgap structure suppresses the third harmonic and the fifth harmonic of the output signal. In other embodiments, the electromagnetic bandgap structure can suppress other higher harmonics by varying the specific structure and parameters of the electromagnetic bandgap structure.

In an embodiment of the invention, the electromagnetic bandgap structure is disposed at the output port position, which not only has the effects of suppressing the third harmonic and the fifth harmonic, but also has a simple structure, low insertion loss, high isolation, and reduction. The loss of microwave during transmission improves the transmission efficiency of microwave. Compared with the Wilkinson power splitter with additional harmonic rejection filter circuit for out-of-band harmonic suppression, the circuit layout area is greatly saved.

The first output port 113 and the second output port 123 are used to output the halved energy to the next circuit unit.

Referring to FIG. 2, FIG. 2 is a waveform diagram of an input/output port reflection coefficient of a Wilkinson power divider according to an embodiment of the present invention. The abscissa represents frequency, the unit is GHz, and the ordinate represents amplitude, and the unit is decibel. The waveform diagram shows the variation of the reflection coefficient of the input port and the output port of the Wilkinson power divider according to an embodiment of the present invention with frequency. . Where S(1,1) represents a waveform diagram of the reflection coefficient of the input port as a function of frequency, S(2,2) represents a waveform diagram of the reflection coefficient of the first output port as a function of frequency, and S(3,3) represents a second output. A waveform diagram of the port reflection coefficient as a function of frequency. As can be seen from the figure, the Wilkinson power splitter has a reflection coefficient S11 of less than -20 dB in the bandwidth of 2.2-2.6 GHz, and the reflection coefficient S22 of the output port is less than -20 dB. It can be seen that the Wilkinson power splitter has small reflection coefficient, small return loss, low reflection power consumption and high transmission power.

Referring to FIG. 3, FIG. 3 is a waveform diagram of the output port insertion loss of the Wilkinson power divider according to an embodiment of the present invention. The abscissa represents the frequency in GHz, and the ordinate represents the amplitude in decibels. This waveform diagram shows the insertion loss of the output port of the Wilkinson power divider in accordance with one embodiment of the present invention as a function of frequency. Where S(2,1) represents a waveform diagram of the insertion loss of the first output port as a function of frequency, and S(3,1) represents a waveform diagram of the insertion loss of the second output port as a function of frequency. As can be seen from the figure, the Wilkinson power splitter has an insertion loss S(2,1) and S(3,1) of less than 0.2 dB for the two output ports in the bandwidth of 2.2-2.6 GHz, and two The phase of the channel is basically the same, so that the two microwave branch signals obtained after the two-power split are in phase, and the power splitting effect is good. At the same time, the Wilkinson power splitter has strong suppression at the third harmonic and the fifth harmonic, with the third harmonic suppression being -30dB and the fifth harmonic suppression being -20dB.

Referring to FIG. 4, FIG. 4 is a waveform diagram of the isolation of the output port of the Wilkinson power divider according to an embodiment of the present invention. The abscissa indicates the frequency in GHz, and the ordinate indicates the amplitude in decibels. This waveform diagram shows the case where the output port isolation of the Wilkinson power divider in the embodiment of the present invention varies with frequency. Where S(3, 2) is the case where the isolation between the first output port and the second output port varies with frequency. As can be seen from the figure, the Wilkinson power splitter has an output port isolation S23 of less than -20 dB in a bandwidth of 2.2-2.6 GHz, and the interference is small.

Referring to FIG. 5 and FIG. 6, FIG. 5 and FIG. 6 are simulation results of an equivalent circuit of an electromagnetic bandgap structure according to an embodiment of the present invention. The abscissa represents the frequency in GHz, and the ordinate represents the amplitude in decibels. The waveform diagram represents the reflection coefficient of the input port of the electromagnetic bandgap structure and the insertion loss of the output port as a function of frequency in one embodiment of the present invention. Happening. Where S(1,1) represents the change of the reflection coefficient of the input port of the electromagnetic bandgap structure with frequency, and S(2,1) represents the case where the insertion loss of the output port of the electromagnetic bandgap structure changes with frequency. It can be seen from the figure that when the microstrip line is considered to be non-consumable, the equivalent circuit of the electromagnetic bandgap structure has stronger suppression ability at the third harmonic and the fifth harmonic. Therefore, the addition of the electromagnetic bandgap structure at the output of the Wilkinson power splitter can effectively suppress the third and fifth harmonics.

Specifically, the signal metal layer and the metal underlayer are made of copper, the dielectric layer is a RO4003C material having a dielectric constant of 3.55, and the input port and the output port have a microstrip line impedance of 50 Ω, and the isolation resistor is connected. Between the first output port and the second output port, the resistance is 100 Ω. In other embodiments, when the Wilkinson power splitter is multi-output, an isolation resistor is connected between every two adjacent output ports, and the resistance value is adjusted differently according to actual conditions.

The Wilkinson power splitter has an electromagnetic bandgap structure at the output port position compared with the conventional Wilkinson power splitter that adds an additional harmonic rejection filter circuit for out-of-band harmonic suppression. The Erjinsen power divider can effectively suppress the third harmonic and fifth harmonic of the output energy, while ensuring good insertion loss, isolation and echo index in the band. On the basis of effectively suppressing the output signal higher harmonics, satisfying the working bandwidth, simple structure, low insertion loss, and high isolation, the circuit layout area is greatly saved.

The above-mentioned embodiments are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but is not to be construed as limiting the scope of the invention. It should be noted that a number of variations and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be determined by the appended claims.

Claims

A Wilkinson power divider comprising a dielectric layer, a signal metal layer attached to one side of the dielectric layer, and a metal underlayer attached to the other side of the dielectric layer, the signal metal layer, the dielectric layer, and the metal The underlayer forms a microstrip line structure, wherein the signal metal layer comprises:

Input port for inputting microwave signals;

a microwave transmission branch having at least two paths and connected to the input port, configured to divide the microwave signal into at least two microwave branch signals;

An output port, configured to output the at least two microwave branch signals, the number of the output ports is matched with the number of the microwave transmission branches, and each output port is respectively connected to one microwave transmission branch;

An electrical tape gap structure is disposed at the output port position for suppressing harmonics generated by the power splitter output signal.
The Wilkinson power splitter according to claim 1, wherein the electromagnetic band gap structure is constructed by at least one of the following:

Attaching a metal patch arranged in a periodic pattern on the signal metal layer;

Forming grooves arranged in a periodic manner on the metal bottom layer;

A regular pattern arranged in a periodic pattern is engraved on the signal metal layer.
The Wilkinson power splitter of claim 1 wherein each of the output port locations is provided with the electromagnetic bandgap structure.
The Wilkinson power splitter according to claim 1, further comprising an isolation resistor, wherein said isolation resistor is connected between adjacent output ports.
The Wilkinson power splitter according to claim 4, wherein the number of the microwave transmission branch circuits is two, and the number of the output ports is two.
The Wilkinson power splitter according to claim 5, wherein the lengths of the two microwave transmission branches are equal, and the widths of the two microwave transmission branches are equal.
The Wilkinson power splitter according to claim 1, wherein the signal metal layer and the metal underlayer are made of copper.
The Wilkinson power splitter of claim 1 wherein said dielectric layer is a RO4003C material having a dielectric constant of 3.55.
The Wilkinson power splitter according to claim 1, wherein the microstrip line structure impedance of the input port and the output port portion is 50 Ω.
The Wilkinson power splitter according to claim 5, wherein the isolation resistor has a resistance of 100 Ω.