CN201134493Y

CN201134493Y - Novel directional coupler

Info

Publication number: CN201134493Y
Application number: CNU2007200774099U
Authority: CN
Inventors: 边登峰; 梁晓鹏; 张潇云; 史作毅; 韩元清
Original assignee: Allrizon Tongguang Communications Equipment Shanghai Co Ltd
Current assignee: Allrizon Tongguang Communications Equipment Shanghai Co Ltd
Priority date: 2007-12-27
Filing date: 2007-12-27
Publication date: 2008-10-15
Anticipated expiration: 2017-12-27

Abstract

The utility model relates to a novel directional coupler, which comprises a coaxial transmission line as a coupling main line and a coupler body having a coupling sub-line. The novel directional coupler is characterized in that the coupler body comprises a coupler seat, a printed circuit board, an adjustable screw and a MCX receptacle, wherein the reverse side of the coupler seat is provided with a groove with stepped internal wall, the front side is provided with a screw hole communicated with the groove bottom and a MCX receptacle extends to the stepped internal wall of the groove, the printed circuit board is fixed on the stepped internal wall of the coupler seat by fastening bolts, the front side of the printed circuit board is provided with matched load, and the reverse side is equipped with a micro-strip line as a coupling sub-line, the adjustable screw is fixed inside the screw hole by a nut, the MCX receptacle is disposed inside a MCX receptacle hole, a PIN of the MCX receptacle is soldered on the printed circuit board, and the coaxial transmission line is fixed rightly below the coupler body and forms an include angle with the micro-strip line on the printed circuit board. The novel directional coupler has small space occupation, convenient debug, simple structure, convenient installation and simple process, which is adapted for mass production.

Description

A kind of novel directional coupler

Technical field

The utility model relates to coupler, particularly relates to a kind of novel directional coupler.

Background technology

Along with developing rapidly of microwave communication, the requirement of communicator is more and more thinner, in order to extract useful signal and to remove unwanted signal from wide and assorted frequency spectrum, filter need be set at the front end of communicator; And, just directional coupler need be set in order to confirm the signal energy situation of filter.

Directional coupler is used for from being provided to input port and extracting sampling in radio or microwave signal that output port receives.Through suitable design, directional coupler can be distinguished signal that is provided to input port and the signal that is provided to output port.This specific character can independently be monitored it and is transmitted and from the signal of mismatch antenna-reflected.

Basic directional coupler is linear, four passive port networks.It comprises 2 parallel coupled transmission lines.Main line is between input port and direct output port, and by-pass is between coupling port and isolated port.The signal that is applied to input port transmits along main line, and causes coupled signal on by-pass.

Can make the degree of coupling of directional coupler by choose reasonable coupled structure and coupling size, isolation, technical indicators such as directivity reach necessary requirement.

The degree of coupling is meant the power output Pc of coupled end and the ratio of the input power Pi of input, is designated as Kc, and unit uses dB always and represents, i.e. formula (1):

Kc＝101g(Pc/Pi) (dB) (1)

Isolation is meant the power output Ps of isolation end and the ratio of the input power Pi of input, is designated as Ks, and unit uses dB always and represents, i.e. formula (2):

Ks＝101g(Ps/Pi) (dB) (2)

Directivity is meant the power output Ps of isolation end and the ratio of the power output Pc of coupled end, is designated as Kd, and unit uses dB always and represents, i.e. formula (3):

Kd＝101g(Ps/Pc) (dB) (3)

From formula (1), (2), (3) as can be known, three's pass is: the directivity=isolation-degree of coupling

Wherein, degree of coupling index is in different application scenarios, and the client has different requirements.But directivity is high more, shows that then the ability of two opposite transmission signals of coupler separation is just strong more, and the performance of coupler is just good more.

Coupler has different implementations in the different field of radio frequency.Coupler in passive cavity filter is generally realized in conjunction with the coupling by-pass of different modes with the main line of coaxial transmission line form.Coupling by-pass form commonly used has: lead resistance is rotatable, two copper rod Air Coupling formulas etc.Because the restriction of structure, exist usually to take up room greatly, with cavity body filter assembling inconvenience, the directivity index was relatively poor when the degree of coupling was very strong, debugging shortcoming such as need repeatedly do over again.

Summary of the invention

Technical problem to be solved in the utility model is exactly to provide for the defective that overcomes above-mentioned prior art existence

The purpose of this utility model can be achieved through the following technical solutions: a kind of novel directional coupler, comprise coaxial transmission line as the coupling main line, the coupler main body that contains the by-pass that is coupled, it is characterized in that, described coupler main body comprises the coupler seat, pcb board, transfer spiral shell, the MCX socket, the reverse side of described coupler seat is provided with inwall and is step-like groove, its front is provided with a screwed hole that is through to bottom land, an and MCX socket aperture that extends to step-like inwall, described pcb board is fixed on the step-like inwall of coupler seat by trip bolt, its front is provided with matched load, reverse side is provided with the microstrip line as the coupling by-pass, described accent spiral shell is fixed in the screwed hole by nut, described MCX socket is located in the MCX socket aperture, and its PIN pin is welded on the pcb board; Described coaxial transmission line be fixed in the coupler main body under, the microstrip line on itself and the pcb board has angle.

Described matched load is two 100ohm Chip-Rs parallel with one another, and these two Chip-Rs are welded on the pcb board by lead-free soldering wire.

Described accent spiral shell adopts M3 to transfer spiral shell.

Described coaxial transmission line is a copper rod.

Compared with prior art, the utlity model has following advantage:

At first, the utility model is only fixed a pcb board on the coupler seat can realize the by-pass that is coupled, compare with other coupler take up room littler;

The second, simple in structure, easy for installation, step is simple, be fit to very much produce in enormous quantities.

The 3rd, debugging is convenient, only need to transfer the spacing of integrally-regulated coupler seat of spiral shell and main line by a M3, can satisfy degree of coupling index, M3 transfers between spiral shell and the matched load and can form additional distributed capacitance again in addition, so that further optimize the directivity index, all debug process will coupler seat integral body not taken out;

The 4th, no matter degree of coupling index request is very strong or very weak, and the utility model all can be realized directivity preferably.

Description of drawings

Fig. 1 is a coupler agent structure schematic diagram of the present utility model;

Fig. 2 is the front schematic view of pcb board of the present utility model;

Fig. 3 is the reverse side schematic diagram of pcb board of the present utility model;

Fig. 4 is the utility model installation diagram;

Fig. 5 is installed on schematic diagram on the filter for the utility model;

Fig. 6 is the upward view of Fig. 5.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

Shown in Fig. 1～6, a kind of novel directional coupler, comprise coaxial transmission line 1 as the coupling main line, the coupler main body 2 that contains the by-pass that is coupled, described coupler main body 2 comprises coupler seat 21, pcb board 22, transfer spiral shell 23, MCX socket 24, the reverse side of described coupler seat 21 is provided with inwall and is step-like groove, its front is provided with a screwed hole that is through to bottom land, an and MCX socket aperture that extends to step-like inwall, described pcb board 22 is fixed on the step-like inwall of coupler seat by trip bolt, its front is provided with matched load 221, reverse side is provided with the microstrip line 222 as the coupling by-pass, described accent spiral shell 23 is fixed in the screwed hole by nut, described MCX socket 24 is located in the MCX socket aperture, and its PIN pin is welded on the pcb board 22; Described coaxial transmission line 1 be fixed in coupler main body 2 under, the microstrip line on itself and the pcb board has angle.

Described matched load is two 100ohm Chip-Rs parallel with one another, and these two Chip-Rs are welded on the pcb board by lead-free soldering wire; Described accent spiral shell adopts M3 to transfer spiral shell; Described coaxial transmission line is a copper rod.

The two ends of main line are to link to each other with connector or other devices by welding manner; By-pass partly is will be fixed on the cavity with its coupler seat that is assembled together by screw after the coupler debugging is finished.

Assembling process of the present utility model is simple, is very suitable for pipelining:

The first step: Chip-R is welded on the pcb board with lead-free soldering wire.

Second step: will put into the coupler seat inwardly with the one side of Chip-R, the pin pin of MCX socket is aimed at the welding hole on the pcb board, and be fixed on the coupler seat with the pan head screw of M1.6*4.

The 3rd step: the pin pin that will pass with lead-free soldering wire on the MCX socket of pcb board welds.

The 4th step: transfer spiral shell to be contained on the coupler seat and M3 and fix with nut.

The 5th step: MCX cable 3 is screwed into MCX socket on the coupler, coupler is put into the cavity groove.

Operation principle: the main line of whole coupler is the transmission copper rod, and one section microstrip line on the pcb board is as the coupling by-pass, and the coupling port of coupler is drawn by the MCX socket on the coupler seat.Can regulate the degree of coupling by moving up and down the coupler seat, if move to the main line direction, the by-pass that then is coupled is nearer with the main line spacing, and the degree of coupling is stronger; If to moving in the other direction, the by-pass that then is coupled becomes big with the main line spacing, and the degree of coupling dies down.The 50ohm matched load that forms in parallel of two 100ohm Chip-Rs on the pcb board.The directivity index is to realize by the coupling by-pass on the adjusting pcb board and the angle of main line.The center of coupler seat is adorned a M3 and is transferred spiral shell, has both made things convenient for coupler is moved up and down to satisfy the degree of coupling, and M3 transfers between spiral shell and the matched load and can form additional distributed capacitance again simultaneously, so that further optimize the directivity index.

The utility model can be suitable for different degree of coupling indexs, is exemplified below:

The utility model is applied to the 800MHz band pass filter, and during work, radiofrequency signal has energy simultaneously and is coupled on the pcb board by the transmission of main line transmission copper rod.Because the degree of coupling of product requirement is very high, reach-10dB, so in the design PCB to go up the coupling by-pass longer relatively, the distance between the coupling by-pass on need further when debugging simultaneously transmission copper rod and the PCB is to satisfy the close coupling requirement.The adding of transferring spiral shell is in order to form additional distributed capacitance, to reach the purpose of optimizing directivity.Debugging is when finishing, and both can realize-the close coupling degree requirement of 10dB that directivity also can reach 22dB～25dB.

The utility model is applied to the 900MHz band pass filter, and during work, radiofrequency signal has energy simultaneously and is coupled on the pcb board by the transmission of main line transmission copper rod.Because the degree of coupling of product requirement is very weak, need-40dB only, so in the design PCB to go up the coupling by-pass shorter relatively, need widen distance between the coupling by-pass on transmission copper rod and the PCB when debugging simultaneously with the satisfied requirement that is coupled.The adding of transferring spiral shell is in order to form additional distributed capacitance, to reach the purpose of optimizing directivity.Debugging is when finishing, and both can realize-the weak coupling degree requirement of 40dB that directivity also can reach 25dB～30dB.

Claims

1. novel directional coupler, comprise coaxial transmission line as the coupling main line, the coupler main body that contains the by-pass that is coupled, it is characterized in that, described coupler main body comprises the coupler seat, pcb board, transfer spiral shell, the MCX socket, the reverse side of described coupler seat is provided with inwall and is step-like groove, its front is provided with a screwed hole that is through to bottom land, an and MCX socket aperture that extends to step-like inwall, described pcb board is fixed on the step-like inwall of coupler seat by trip bolt, its front is provided with matched load, reverse side is provided with the microstrip line as the coupling by-pass, described accent spiral shell is fixed in the screwed hole by nut, described MCX socket is located in the MCX socket aperture, and its PIN pin is welded on the pcb board; Described coaxial transmission line be fixed in the coupler main body under, the microstrip line on itself and the pcb board has angle.

2. a kind of novel directional coupler according to claim 1 is characterized in that, described matched load is two 100ohm Chip-Rs parallel with one another, and these two Chip-Rs are welded on the pcb board by lead-free soldering wire.

3. a kind of novel directional coupler according to claim 1 is characterized in that, described accent spiral shell adopts M3 to transfer spiral shell.

4. a kind of novel directional coupler according to claim 1 is characterized in that described coaxial transmission line is a copper rod.