KR100714867B1 - Wideband hybrid coupler by using symmetrical multi-stage coupled lines - Google Patents

Abstract

The present invention relates to a broadband hybrid coupler using a symmetric multistage coupling line.

The present invention can design the desired bandwidth and band section by controlling the number of lines and design variables by applying a broadband technique and a tandem type coupler, and using a minimum of wire bonding (1) It offers a broadband hybrid coupler that can improve performance.

According to the present invention, it is possible to expect the effect of designing a desired bandwidth and band section by adjusting the number of lines and design variables by applying a broadband technique and a tandem type combiner.

Coupler, Hybrid, Coupler, Broadband, Multistage Coupling Line

Description

Wideband Hybrid Coupler by Using Symmetrical Multi-Stage Coupled Lines

1 is a diagram illustrating a 90 ° wide band 3 dB coupler using a conventional N-stage parallel coupling line.

2 is a diagram illustrating a broadband hybrid coupler using a symmetric multi-stage coupling line according to an embodiment of the present invention.

3 is a diagram showing the wideband theory of the microstrip directional coupler applied to the embodiment of the present invention.

4 is a plan view of a broadband hybrid coupler showing design values in accordance with a design specification according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating broadband characteristics as a result of simulating a broadband hybrid coupler according to an embodiment of the present invention. FIG.

6 is a diagram illustrating a phase difference of an output signal as a result of simulating a broadband hybrid coupler according to an embodiment of the present invention.

The present invention relates to a broadband hybrid coupler using a symmetric multi-stage coupled line. A wideband hybrid capable of designing a desired bandwidth and band section by controlling the number of stages and design variables by applying a broadband technique and a tandem type coupler. It's about a coupler.

Coupling generally refers to a phenomenon in which AC signal energy is electromagnetically transmitted between separate spaces or lines.

Interference between lines refers to the occurrence of unwanted noise signals or transmissions and disturbances due to the coupling between lines.

The coupler is an apparatus that artificially adjusts the degree of the coupling, and arbitrarily adjusts the length and spacing of the line so that the desired power is transmitted to one side.

Coupler is used to extract or distribute as much power as you want by using coupling phenomenon, and it can be used in various ways such as Branch-Line Coupler, Ring Hybrid Coupler, Wilkinson Coupler, etc. Can be configured.

However, these couplers have the advantage of ease of manufacture but are inadequate for circuits requiring broadband.

As a result, the directional coupler using the broadband characteristics of the parallel coupling line has been used, but there are limitations in the actual implementation even though there is a broadband characteristic than the branch-line or ring type.

In other words, the coupler to obtain a high coupling amount should have a large difference between the right mode and the pre-mode impedance, and to realize this, the coupling distance should be up to several tens of micrometers. However, it is not easy to realize the coupling gap of the actual coupler up to several tens of micrometers.

The solution to this problem is to use a kemp type or tandem type coupler that lengthens the microstrip line length or combines it in a wide plane in order to increase the amount of coupling. There is a disadvantage that it becomes large or uses a multilayer board.

Therefore, a method of implementing a 3dB coupler that satisfies both broadband and ease of fabrication has been proposed.

1 is a diagram illustrating a 90 ° wide band 3 dB coupler using a conventional N-stage parallel coupling line.

As shown in FIG. 1, the conventional invention uses a parallel coupling line to have a wide bandwidth, and analyzes an N-stage parallel coupling line to design a random coupling amount and a minimum coupler size, and analyzes a 4-port S-parameter. Extracted.

Conventional invention is a principle of adjusting the width and spacing of the coupler in a structure that connects the coupling lines in parallel in order to obtain the maximum coupling amount with the minimum circuit size.

In the conventional invention, when a coupler of about three stages is used, a low pre-mode impedance must be made to realize a 3dB coupler with a minimum number of stages. For this purpose, a substrate having a high dielectric constant and a high dielectric height of a substrate should be used.

For this reason, the related art shows a performance similar to that of 40%, which is the bandwidth of the Lange coupler, and has an advantage of being able to be implemented with low impedance.

However, the related art has a disadvantage in that the coupling amount of the single coupler is reduced due to the high impedance of the interdigitated shape.

In addition, in the conventional invention, when the number of stages increases, the circuit size increases proportionally, the number of wire bonding increases, and the overall performance decreases. As a result, a band limitation occurs because a λ / 4 parallel coupling line is used. There is a problem.

In order to solve this problem, the present invention is to provide a broadband hybrid coupler that can design the desired bandwidth and band section by controlling the number and design parameters of the line by applying a broadband technique and Tandem Type combiner Its purpose is.

According to one aspect of the present invention, a wideband hybrid coupler using a symmetric multi-stage coupling line according to an aspect of the present invention has an input port through which an input signal is introduced, and an isolation port for consuming leakage power on the other side. A first multistage parallel coupling line having a shape in which the width of each stage is wider as the number of stages increases; And a second multistage parallel coupling line having a coupling port configured to output a coupling signal on one side thereof, and having a width in which each stage becomes wider as the number of stages increases, wherein the second multistage parallel coupling line is wire bonded. Bonding) includes a broadband hybrid coupler characterized in that it is connected to the pass-through port outputting the pass signal provided on one side of the substrate.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, it means that it may further include other components, without excluding other components unless otherwise stated.

Now, a broadband hybrid coupler using a symmetric multistage coupling line according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a diagram illustrating a broadband hybrid coupler using a symmetric multi-stage coupling line according to an embodiment of the present invention.

The broadband hybrid coupler according to the embodiment of the present invention connects a multi-stage coupling line to a series of TEM-mode couplers so as to be manufactured and processed in a single process using a coupling structure of a microstrip coupling pattern on the substrate 250. Here, the TEM-mode refers to a transmission mode in which an electric field and a magnetic field exist only on a vertical plane in a progressing direction among the transmission modes of the electromagnetic field.

In the exemplary embodiment of the present invention, the first multi-stage parallel coupling line 260 and the second multi-stage parallel coupling line 270 form a symmetrical structure and are connected in a tandem type on the substrate 250.

One side of the first multi-stage parallel coupling line 260 forms an input port 200, one end of the other side is connected to the second multi-stage parallel coupling line 270, and the other end of the first multi-stage parallel coupling line 260 is isolated and disconnected without leakage power. It forms an isolation port 240 that consumes.

One side of the second multistage parallel coupling line 270 forms a coupling port 220 which is an output port, one end of which is connected to the first multistage parallel coupling line 260, and the other end of which is wire bonding. 230 is connected to a pass port 210 which is an output port formed on one side of the substrate 250.

In brief, the broadband hybrid coupler according to the exemplary embodiment of the present invention has a symmetrical multi-stage coupling line formed in a tandem type on a substrate 250 to form an input port 200 and an output port coupling port 220. ), A pass port 210 and an isolation port 240 which are output ports to form one input signal and two output signals.

The first multi-stage parallel coupling line 260 and the second multi-stage parallel coupling line 270 control the bandwidth by adjusting the number of stages, and control the coupling amount by adjusting the width and spacing.

In addition, when the broadband hybrid coupler supplies an input signal to the input port 200, a combined signal that is an output signal is output to the coupling port 220, and an output signal to the pass port 210 through the wire bonding 230. Phosphorus pass signal is output.

The two outputs, the combined signal and the pass signal, have a function of equally distributing half and half power, or -3 dB power, with a phase difference of 90 degrees.

The isolation port 240 of the broadband hybrid coupler is a port that is terminated by terminating resistors according to the line impedance and is not actually used for input / output.

The isolation port 240 of the broadband hybrid coupler is used for stabilizing the power of the coupler by functioning to ground it with a resistor so that leakage of the leakage power is not reflected because power is not transmitted structurally.

As described above, the broadband hybrid coupler connects the first multi-stage parallel coupling line 260 and the second multi-stage parallel coupling line 270, that is, -8.34 dB coupler and -8.34 dB coupler in two stages in series to output an output of -3 dB. This 90 degree phase difference outputs. This structure is called a tandem type coupler.

The broadband hybrid coupler has a structure that can gradually reduce the impedance of the even mode by applying a broadband technique in addition to a tandem type coupler. Hereinafter, the broadband technique is described in detail with reference to FIG. 3.

The embodiment of the present invention implements a 3dB coupler that satisfies both broadband and ease of fabrication by using a broadband technique and a tandem type coupler.

3 is a diagram showing the wideband theory of the microstrip directional coupler applied to the embodiment of the present invention.

As shown in Fig. 3, the multi-stage directional coupler is connected to a series of TEM-mode couplers. Each stage has its own electrical length.

Coupling in each stage gradually weakens from left to right. An important feature of this directional coupler is that it is a TEM-mode coupler with different characteristics.

In theory, VSWR (Voltage Standing Wave Ratio) and isolation are optimized.

Couplings are simply expressed as a function of frequency and can be synthesized and modified using Modern Network technology. Wideband coupling can be implemented with Chebyshev Equel-Ripple Function.

Coupling at each stage is defined as Z _Oe and Z _Oo , which are Even Mode and Odd Mode, respectively. Here, the impedance is normalized with respect to the input characteristic impedance, and the normalized impedance is as follows.

If the above relationship is satisfied, VSWR (Voltage Standing Wave Ratio) and isolation can be optimized.

Therefore, the coupling stage may determine the coupling value by the Even Mode which is Z _Oe .

This is because the impedance magnitude satisfies the condition of Z _Oe > Z _Oo and Z _Oe > 1. Broadband characteristics can be obtained by gradually reducing the impedance of Even Mode.

4 is a plan view of a broadband hybrid coupler showing design values in accordance with a design specification according to an embodiment of the present invention, and FIG. 5 is a diagram showing broadband characteristics as a result of simulating a broadband hybrid coupler according to an embodiment of the present invention. 6 is a diagram showing the phase difference of the output signal as a result of simulating the broadband hybrid coupler according to the embodiment of the present invention.

One embodiment of the broadband hybrid coupler was implemented with design values that match the substrate information and design specifications listed in Table 1 and the design specifications listed in Table 2 below.

W1 W2 W3 W4 W5 W6 11 12 0.4 0.9 0.9 0.9 0.9 1.16 7 2.177 13 14 15 16 s1 s2 s3 s4 2.355 4.809 One 6 0.08 0.15 0.6 1.8

As shown in FIG. 5 and FIG. 6, the embodiment of the present invention shows a broadband characteristic of 113% at approximately 1.6 GHz to 5.8 GHz as a result of designing and simulating a broadband hybrid coupler.

(1.6 GHz- > through: -3.011 dB, coupling: -3.847 dB,

5.8 GHz- > through: -3.978 dB, coupling: -3.157 dB )

The band that satisfies both the coupling and the bandwidth simultaneously forms 1.6% to 4GHz, forming 85% of the bandwidth. However, the condition is 1dB Unblance, the isolation is less than -10dB, and the phase difference is 90 ^o +/- 10.

(1.6 GHz- > through: -3.011 dB, coupling: -3.847 dB, through phase: 175.074 ^o , coupling phase: -99.821 ^o ,

4 GHz- > through: -3.661 dB, coupling: -3.386 dB, through phase: 13.838 ^o , coupling phase: -85.528 ^o )

The results shown in FIGS. 5 and 6 can be confirmed that the results are more than doubled compared to the bandwidth of 42% of the existing Tandem Type Coupler or Lange Coupler. All the processes of the above design are values considering 0.08 mm, which is the actual etchable width and spacing.

The embodiment of the present invention implements a broadband hybrid coupler having a -3dB output and a phase difference of 90 degrees using a symmetric multistage coupling line.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

According to the above-described configuration, the present invention showed excellent performance higher than the bandwidth of the Lange coupler (Range Coupler) 40% and can be expected to implement the effect that can be implemented with a low impedance compared to the implementation of the high impedance of the shape of the shell.

In addition, the present invention can be expected to overcome the difficulties of circuit design by applying a broadband technique of a parallel coupling line to break away from the existing Lange coupler design technology.

In addition, the present invention can be expected to effect the design of the desired bandwidth and band section by adjusting the number and design parameters of the line by applying a broadband technique and Tandem Type combiner.

In addition, the present invention can be expected to reduce the number of wire bonding (wire bonding) that is a difficult point of the existing Lange coupler (Lange Coupler) by minimizing the number of stages.

Claims (4)

In a broadband hybrid coupler using a symmetric multistage coupling line, A first multi-stage parallel coupling line having an input port into which an input signal flows into one side, an isolation port consuming leakage power on the other side, and a width of each stage wider as the number of stages increases; And A second multi-stage parallel coupling line having a shape in which a coupling port for outputting a coupling signal is formed at one side and the width of each stage is increased as the number of stages increases; And the second multi-stage parallel coupling line is connected to a pass port through which a pass signal provided on one side of the substrate is output by wire bonding. The method of claim 1, And said first multistage parallel coupling line and said second multistage parallel coupling line are configured as tandem type couplers and are connected in two stages in series. The method of claim 1, And the power of the combined signal and the passed signal output from the combined port and the passing port is -3 dB, respectively, and the phase difference between the combined signal and the passing signal is 90 degrees. The method of claim 1, Broadband hybrid coupler, characterized in that the bandwidth is controlled by adjusting the number of stages of the first multi-stage parallel coupling line and the second multi-stage parallel coupling line, and the coupling value by controlling the width and spacing.

Images