CN200976581Y

CN200976581Y - Directional coupler

Info

Publication number: CN200976581Y
Application number: CN 200620160096
Authority: CN
Inventors: 田涛; 陈建军; 沈俭; 巨刚; 崔亚楠
Original assignee: Huawei Technologies Co Ltd
Current assignee: Shenzhen Huawei Agisson Electric Co Ltd
Priority date: 2006-11-28
Filing date: 2006-11-28
Publication date: 2007-11-14
Anticipated expiration: 2016-11-28

Abstract

The utility model discloses a directive coupler, comprising a cavity, two metal-bars, and four terminals. The two metal-bars are in parallel arranged at the cavity and insulated with the cavity; the four terminals are connected with the four electric terminals of the two metal-bars and are penetrated to the cavity insulated; the utility model also comprises at least a metal protrusion, which is arranged between the metal-bars and is connected with the bottom of the cavity. The utility model augments self-capacitance and minimizes mutual-capacitance between metal-bars by adding metal protrusion between metal-bars, which makes the proportion of an electric component and a magnetic component stable, and makes the odd module phase velocity and the even module phase velocity tend to equal; therefore, the directivity is improved; the request of high-power, low insertion loss and good cross modulation index of the co-axle coupler is preserved.

Description

Directional coupler

Technical field

The utility model relates to wireless communication technology field, especially refers to a kind of directional coupler.

Background technology

Directional coupler is the network that microwave signal is carried out according to a certain percentage power division, it is one of the most frequently used element of microwave technical field, and concrete effect is microwave to be coupled out a certain proportion of microwave energy enter secondary transmission line and propagate along a direction in secondary transmission line from main transmission line.

Directivity is directional coupler is distinguished incident wave and reflected wave ability in an emission system a module.The directivity of directional coupler is defined as the difference of the coupler isolation and the degree of coupling, four port network schematic diagrames with directional coupler in the prior art shown in Figure 1 are example, in illustrated four port networks, definition P1 is the input port of feed-in power, then P2 and P3 are for extracting the coupling aperture of coupled power, and P4 is an isolated port.Then,

The coupling coefficient of port 3: C=-10log (P3/P1)

The isolation of port 4: I=-10log (P4/P1)

The directivity of directional coupler is: D=I-C

Therefore, when the degree of coupling was determined, isolation was high more, and then directivity is good more.

By the characteristic of directional coupler as can be known, its directivity depends on electric field component and the magnetic-field component in the coupling circuit, and directivity was best when the component that produces when these two sources was balanced.And the value of electromagnetic field component depends on coupling capacitance, inductance on the coupling plate.Desirable Directivity of Directional Coupler is infinitely great, but in fact untenable.Coupler performance will degenerate, frequency band narrows down and directivity reduces because the error of process and assemble, the realization of coaxial impedance all will cause.Implementation with two kinds of directional couplers in the prior art is that example is set forth characteristics separately below.

Fig. 2 is the internal structure schematic diagram of coaxial type directional coupler in the prior art, and as shown in the figure, it adopts the coaxial line of metal structure to realize coupling.Though this structure can satisfy powerful requirement, also can satisfy the intermodulation index, Insertion Loss is also little, and the directivity index can't reach more than the 28dB, generally all about 18dB, can not satisfy the needs of extensive use.Fig. 3 is the internal structure schematic diagram of microstrip type directional coupler in the prior art, and as shown in the figure, it adopts microstrip line construction to realize coupling.Because microstrip line cloth onboard, so structure is flexible relatively, can be by changing microstrip line construction, realize high directivity, it is not high that but the shortcoming of this structure is a power capacity, and the intermodulation index is also bad, even use PCB (the Printed Circuit Board of low intermodulation, printed circuit board (PCB)) solve the intermodulation problem, the problem that the high-power and Insertion Loss of little band plate is big still can't solve.

The utility model content

The purpose of this utility model provides a kind of directional coupler, with the high directivity and the high power capacity that solve directional coupler in the prior art, hang down the defective that intermodulation and little Insertion Loss can not be realized simultaneously.

For achieving the above object, the utility model proposes a kind of directional coupler, comprise cavity, two Metallic rod and four terminals, described two Metallic rod are arranged in parallel in described cavity, and insulate with described cavity; Described four terminals electrically connect with four ends of described two Metallic rod respectively, and insulation penetrate described cavity; Also comprise at least one metal ridge, described metal ridge is arranged between described two Metallic rod, and is connected with cavity bottom.

Above-mentioned directional coupler is by setting up one or more metal ridges on the cavity between two coupling Metallic rod, the electric field component of mutual coupling between the Metallic rod and the ratio of magnetic-field component are tended to balance, also make strange mould phase velocity and even mould phase velocity be tending towards equal, thereby improve the directivity of directional coupler; Simultaneously keep the coaxial type directional coupler again and satisfied high-power requirement, Insertion Loss is little and the intermodulation index is good characteristic.

Description of drawings

Fig. 1 is four port network schematic diagrames of directional coupler in the prior art;

Fig. 2 is the internal structure schematic diagram of coaxial type directional coupler in the prior art;

Fig. 3 is the internal structure schematic diagram of microstrip type directional coupler in the prior art;

Fig. 4 is the utility model directional coupler first embodiment internal structure schematic diagram;

Fig. 5 is the profile of the utility model directional coupler first example structure among Fig. 4;

Fig. 6 is the utility model directional coupler second embodiment internal structure schematic diagram;

Fig. 7 is the profile of the utility model directional coupler second example structure among Fig. 6.

Embodiment

In conjunction with the accompanying drawings the utility model is further set forth with specific embodiment below.

Fig. 4 is the utility model directional coupler first embodiment internal structure schematic diagram.As shown in Figure 4,421,422 and four terminals 431,432,433 and 434 of two Metallic rod that directional coupler comprises cavity 410, is parallel to each other, wherein Metallic rod 421,422 is supported in the cavity 410 by four terminals 431～434 that insulation is inserted in cavity 410 bottoms.The directional coupler of present embodiment also comprises two screws 441,442, and it is located at the cavity bottom between the Metallic rod 421,422.Wherein, cavity 410 is a conductor, is particularly made by metal material, and screw 441,442 can pass through cavity 410 ground connection thus.Fig. 5 is that the present embodiment directional coupler has shown the state that is provided with of Metallic rod through the profile of Metallic rod 422 axis among Fig. 4.In addition, terminal 431～434 electrically connect with four ends of Metallic rod 421,422 respectively and insulation penetrate cavity 410, with importing and the derivation of carrying out microwave, it specifically can be realized by the conductor that covers insulating material outward, as shown in Figure 5, terminal 433 promptly comprises conductor cores 4331 and outer insulating layer coating 4332.

Among above-mentioned first embodiment, screw 441,442 set up the self-capacitance that can increase between the Metallic rod 421,422, simultaneously reduced the mutual capacitance between two Metallic rod again, the electric field component of mutual coupling between the Metallic rod 421,422 and the ratio of magnetic-field component are tended to balance, also make strange mould phase velocity and even mould phase velocity be tending towards equal, thereby improve the directivity of directional coupler.In the design of directional coupler, position that can be by mobile screw 441,442, the perhaps height of adjustment screw 441,442 changes the electric capacity between the Metallic rod 421,422 of coupling, thereby realizes the adjusting of directivity, to satisfy different application.Simultaneously because the characteristic that screw connects, its with cavity 410 between can flexibly connect, so in the application after directional coupler is made, can realize adjusting by the height of adjustment screw equally to Directivity of Directional Coupler.

In addition, the directional coupler of finished product also should comprise the loam cake of cavity 410, and it is not essential features of the present utility model place, and illustrated cut-away view is failed to show, also do not given unnecessary details in present embodiment and following second embodiment.

Fig. 6 is the utility model directional coupler second embodiment internal structure schematic diagram.As shown in Figure 6,621,622 and four terminals 631～634 of two Metallic rod and four insulation stents 641～644 that directional coupler comprises cavity 610, is parallel to each other, wherein Metallic rod 621,622 is supported in the cavity 610 by the insulation stent 641～644 that insulation is fixed on cavity 610 bottoms.In the present embodiment, directional coupler also comprises two thin rectangular build metallic walls 651,652, and the cavity bottom that it is located between the Metallic rod 621,622 is grounded by cavity 610.

Fig. 7 is that the present embodiment directional coupler has shown the state that is provided with that Metallic rod 622 supports by insulation stent 643,644 through the cutaway view of Metallic rod 622 axis among Fig. 6.In addition, terminal 631～634 is arranged at the sidewall of cavity 610, its electrically connect with four ends of Metallic rod 621,622 respectively and insulation penetrate cavity 610, as shown in Figure 7, terminal 633 comprises conductor cores 6331 and outer insulating layer coating 6332, utilizes this structure to realize the importing and the derivation of microwave.Because Metallic rod 622 is also can be only fixing by terminal 633,634, so supporter 643,644 can save, but supporter 643,644 is set can fix this Metallic rod 622 better, to increase stability.And acting as of outer insulating layer coating 6332 makes Metallic rod 622 and terminal 633 and cavity 610 insulation, so it can only be arranged on the adjacent part of terminal 633 and cavity 610.In conjunction with above-mentioned first and second embodiment as can be known, the position of terminal or insulation stent can be provided with arbitrarily according to different application needs in the utility model directional coupler, it is provided with form, and also to be not limited to above two embodiment described, only need to guarantee that insulation setting and normally the importing and exporting of microwave signal of Metallic rod in cavity gets final product, those variations are not essential features of the present utility model place, are no longer to be given unnecessary details.

Identical with above-mentioned the utility model first embodiment principle, metallic walls 651,652 set up the self-capacitance that can increase between the Metallic rod 621,622, simultaneously reduced the mutual capacitance between two Metallic rod again, the electric field component of mutual coupling between the Metallic rod 621,622 and the ratio of magnetic-field component are tended to balance, also make strange mould phase velocity and even mould phase velocity be tending towards equal, thereby improve the directivity of directional coupler.In like manner, in the design of directional coupler, can change the electric capacity between the Metallic rod 621,622 of coupling by height, thickness, length and the position of control metallic walls 651,652, thereby realize adjusting, to satisfy different application to Directivity of Directional Coupler.

Elaboration by above two specific embodiments, adopt the structure of the utility model directional coupler, each parameter index all has surplus, when design, have the bigger degree of freedom, and can by adjustment screw or the size that changes metallic walls eliminate because the situation that the directivity that rigging error, structure tolerance are brought worsens, and regulative mode is simple, is beneficial to debugging, and production efficiency is higher.In addition, the metal ridge that the utility model directional coupler is set up is not limited to the screw or the metallic walls of the foregoing description, can also be other shape, as the cylinder type metallic pin, is not technical characterictic of the present utility model place herein, is no longer given unnecessary details.

More than disclosed only be several specific embodiment of the present utility model, still, the utility model is not limited thereto, any those skilled in the art can think variation all should fall into protection range of the present utility model.

Claims

1, a kind of directional coupler comprises cavity, two Metallic rod and four terminals, and described two Metallic rod are arranged in parallel in described cavity, and insulate with described cavity; Described four terminals electrically connect with four ends of described two Metallic rod respectively, and insulation penetrate described cavity; It is characterized in that, also comprise at least one metal ridge, described metal ridge is arranged between described two Metallic rod, and is connected with cavity bottom.

2, directional coupler according to claim 1 is characterized in that described metal ridge is a screw.

3, as directional coupler as described in the claim 2, it is characterized in that, between described screw and the cavity for flexibly connecting or fixedlying connected.

4, directional coupler according to claim 1 is characterized in that described metal ridge is rectangular build metallic walls.

5, directional coupler according to claim 1 is characterized in that described metal ridge is the cylinder type metallic pin.

6, directional coupler according to claim 1 is characterized in that described four terminals are arranged at the bottom of described cavity.

7, directional coupler according to claim 1 is characterized in that described four terminals are arranged at the sidewall of described cavity.

8, as directional coupler as described in claim 1 or 6 or 7, it is characterized in that also comprise insulation stent, described insulation stent is arranged in the described cavity, support the setting of in described cavity, insulating of described two Metallic rod.

9, as directional coupler as described in the claim 8, it is characterized in that described insulation stent vertically is inserted in the bottom of described cavity.