CN110247147B

CN110247147B - Microstrip band-pass power divider

Info

Publication number: CN110247147B
Application number: CN201910614119.0A
Authority: CN
Inventors: 肖飞; 袁斌; 王余成
Original assignee: University of Electronic Science and Technology of China
Current assignee: University of Electronic Science and Technology of China
Priority date: 2019-07-09
Filing date: 2019-07-09
Publication date: 2021-06-08
Anticipated expiration: 2039-07-09
Also published as: CN110247147A

Abstract

The invention provides a microstrip band-pass power divider which simultaneously realizes the functions of filtering and power division, thereby effectively reducing the size of elements. The microstrip band-pass power divider realizes a fourth-order band-pass frequency response, has a transmission zero at the limited frequency on the right side of the passband, and can improve the frequency selectivity on the right side of the passband; in addition, the output port can obtain higher isolation in a wider frequency range. The microstrip band-pass power divider has the advantages of superior performance, simple design process and the like.

Description

Microstrip band-pass power divider

Technical Field

The invention belongs to the technical field of communication, and particularly relates to a microstrip power divider with band-pass frequency response.

Background

In higher frequency bands such as radio frequency/microwave/optical frequency and the like, the microstrip line has the advantages of small volume, light weight, wide use frequency band, high reliability, low manufacturing cost and the like, and is a transmission line with wide application. The microstrip line has a distributed parameter effect, and the electrical characteristics of the microstrip line are closely related to the structural size. The power divider is called a power divider, and is an important device in a communication or radar system. The device divides one path of input signal energy into two paths or multiple paths of input signal energy which are output with equal or unequal energy, and can also synthesize the multiple paths of signal energy into one path of output in turn, and at the moment, the device can also be called a combiner. Since the power divider can be used in reverse as a combiner, the following discussion takes the power divider as an example. Certain isolation degree should be guaranteed between output ports of one power divider. In addition, the filter is another microwave device, and functions to allow signals of a certain frequency to pass through smoothly, and allow signals of another frequency to be greatly suppressed. Conventional filters and power splitters are two separate components that assume different functions.

Disclosure of Invention

In order to overcome the defect that the traditional power divider and a filter belong to two elements and have larger sizes, the invention provides a novel micro-strip power divider which can simultaneously realize the functions of band-pass filtering and power division and has the advantages of good frequency selectivity, good isolation, small size, easy design and the like. Hereinafter referred to as microstrip bandpass power divider.

The structure of a typical microstrip is shown in fig. 1 and mainly comprises three layers. The first layer is a metal upper cladding layer, the second layer is a dielectric substrate, and the third layer is a metal lower cladding layer. The microstrip band-pass power divider disclosed by the invention is shown in figure 2, and is arranged in a metal upper cladding (I), and is characterized in that: a first Port (Port #1) is connected to the left end of the middle section of the parallel coupled three-wire structure (1); the right end of a lateral line section on the parallel coupling three-line structure (1) is connected to a first terminal open-circuit branch section (21) and is simultaneously connected to a first transmission line section (22) of a middle loading short-circuit branch section; a first transmission line section (22) of the middle loading short-circuit branch section is connected to a second terminal open-circuit branch section (23) and is simultaneously connected to the right side of a first parallel coupling two-wire structure (24); the left side of the first parallel-coupled two-wire structure (24) is connected to a second Port (Port # 2); the right end of the lower side wire section of the parallel coupling three-wire structure (1) is connected to a third terminal open-circuit branch section (31) and is simultaneously connected to a second transmission wire section (32) of the middle loading short-circuit branch section; a second transmission line section (32) of the middle loading short-circuit branch section is connected to a fourth terminal open-circuit branch section (33) and is simultaneously connected to the right side of a second parallel coupling two-wire structure (34); the left side of the second parallel-coupled two-wire structure (34) is connected to a third Port (Port # 3); the first resistor (R1) is bridged at the outer side wire joint at the left end of the parallel coupling three-wire structure (1), and the second resistor (R2) is welded between the first transmission line joint (22) of the middle loading short-circuit branch joint and the second transmission line joint (32) of the middle loading short-circuit branch joint; the short circuit is realized by a metallized via.

Furthermore, the microstrip bandpass power divider can realize a fourth-order bandpass frequency response, has a transmission zero at the limited frequency on the right side of the passband, and can improve the frequency selectivity on the right side of the passband.

The microstrip band-pass power divider has the beneficial effects that: one path of input signals can be divided into two paths to be output, and on the contrary, the two paths of input signals can be combined into one path to be output; the power divider has band-pass frequency response, and the right side of the pass band is provided with a transmission zero point, so that the frequency selectivity is greatly improved; the isolation between the output ports is high; the size is less, the design process is simple, and the debugging is easy.

Drawings

FIG. 1: a schematic structural diagram of a microstrip line;

FIG. 2: a schematic diagram of a microstrip band-pass power divider;

FIG. 3: marking a schematic diagram of structural parameters of the microstrip band-pass power divider;

FIG. 4: example | S₂₁I and I S₁₁A | test result graph;

FIG. 5: examples of the invention|S₃₂And | testing result graph.

Detailed Description

In order to embody the inventive and novel aspects of the present invention, the following description is made with reference to the accompanying drawings and specific examples, but the embodiments of the present invention are not limited thereto. Without loss of generality, the embodiment selects a common microstrip substrate with a relative dielectric constant of 3.66 and a substrate thickness of 0.508 mm.

Structural parameters of the embodiment are labeled as shown in FIG. 3₁、l₂、l₃And l₄Denotes the length, w₁、w₂、w₃、w₄、w₅And w₆Represents the line width, s₁And s₂Indicating the slot width and d the metalized via diameter. The specific values are (unit: mm): l₁＝14.9,l₂＝12.07,l₃＝1.55,l₄＝1.41,w₁＝0.12,w₂＝0.64,w₃＝0.66,w₄＝0.55,w₅＝0.53,w₆＝0.35,s₁＝0.17,s₂0.13 and d 0.4. Furthermore, R₁＝820Ω,R₂330 Ω. Electromagnetic simulation and processing were performed on the examples, and the simulation and test results are shown in fig. 4 and 5. The microstrip band-pass power divider can realize a fourth-order band-pass frequency response, and has a transmission zero at 4.0GHz on the right side of a passband, so that the frequency selectivity is effectively improved. The center frequency of the band-pass frequency response is located at 2.92GHz, the 3dB relative bandwidth is 57.3%, the insertion loss at the center frequency is 0.17dB, the in-band return loss is greater than 12dB, the rejection in the frequency range from 4.0GHz to 7.3GHz is greater than 28dB, and the isolation in the frequency range from direct current to 8.0GHz is greater than 21 dB. The dimensions of the examples are 0.341 lambda_g×0.154λ_gWherein λ is_gIs the corresponding waveguide wavelength at the center frequency.

The embodiments listed above fully demonstrate that the microstrip bandpass power divider of the present invention has the advantages of good frequency response, small size, simple design process, etc., and has significant technical progress. It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.

Claims

1. A microstrip band-pass power divider is characterized in that: a first Port (Port #1) is connected to the left end of the middle section of the parallel coupled three-wire structure (1); the right end of a lateral line section on the parallel coupling three-line structure (1) is connected to a first terminal open-circuit branch section (21) and is simultaneously connected to a first transmission line section (22) of a middle loading short-circuit branch section; a first transmission line section (22) of the middle loading short-circuit branch section is connected to a second terminal open-circuit branch section (23) and is simultaneously connected to the right side of a first parallel coupling two-wire structure (24); the left side of the first parallel-coupled two-wire structure (24) is connected to a second Port (Port # 2); the right end of the lower side wire section of the parallel coupling three-wire structure (1) is connected to a third terminal open-circuit branch section (31) and is simultaneously connected to a second transmission wire section (32) of the middle loading short-circuit branch section; a second transmission line section (32) of the middle loading short-circuit branch section is connected to a fourth terminal open-circuit branch section (33) and is simultaneously connected to the right side of a second parallel coupling two-wire structure (34); the left side of the second parallel-coupled two-wire structure (34) is connected to a third Port (Port # 3); the first resistor R1 is bridged at the outer side wire joint at the left end of the parallel coupling three-wire structure (1), and the second resistor R2 is welded between the first transmission line joint (22) of the middle loading short-circuit branch joint and the second transmission line joint (32) of the middle loading short-circuit branch joint; short circuiting is achieved through the metallized via holes; the microstrip band-pass power divider realizes a fourth-order band-pass frequency response and has a transmission zero at a limited frequency on the right side of a passband.

2. The microstrip bandpass power divider according to claim 1, based on a microstrip substrate, having a relative dielectric constant of 3.66 and a substrate thickness of 0.508 mm; l₁、l₂、l₃And l₄Denotes the length, w₁、w₂、w₃、w₄、w₅And w₆Indicating line width，s₁And s₂Representing the slot width, d represents the metalized via diameter; selecting parameters: l₁＝14.9mm,l₂＝12.07mm,l₃＝1.55mm,l₄＝1.41mm,w₁＝0.12mm,w₂＝0.64mm,w₃＝0.66mm,w₄＝0.55mm,w₅＝0.53mm,w₆＝0.35mm,s₁＝0.17mm,s₂＝0.13mm，d＝0.4mm，R₁＝820Ω,R₂330 Ω; the center frequency of the achieved fourth-order band-pass frequency response is located at 2.92GHz, the 3dB relative bandwidth is 57.3%, the rejection in the frequency range from 4.0GHz to 7.3GHz is over 28dB, and the isolation in the frequency range from direct current to 8.0GHz is over 21 dB.