KR20100005617A - Single transmission line for plurality of antenna - Google Patents

Abstract

PURPOSE: A single transmission line for feeding a plurality of antennas is provided to feed a signal to the antennas by alternatively forming a plurality of ground patterns and a plurality of signal patterns on a single board. CONSTITUTION: A plurality of signal patterns(204,208) are formed on a flexible printed circuit board(200). An RF(Radio Frequency) signal is applied to a plurality of signal patterns. A plurality of ground patterns(202,206) are formed on the flexible printed circuit board. The plurality of ground patterns are electrically connected to the ground in a terminal. The plurality of signal patterns and ground patterns are alternatively formed on the flexible printed circuit board. The plurality of signal patterns supply an RF signal to different antennas.

Description

Single transmission line for multi-antenna power supply {Single Transmission Line for Plurality of Antenna}

The present invention relates to an RF transmission line, and more particularly to a single transmission line for feeding a plurality of antennas.

Transmission line is a device used to transmit an RF signal, the RF signal output from the transmitter output terminal is provided to the antenna through the transmission line and the antenna radiates it to the outside.

Transmission lines include various types of transmission lines, such as coaxial cables, micro strip lines, through tips, and coplanar transmission lines.

On the other hand, in recent years, the demand for convergence (convergence) terminal that provides a variety of communication services in one terminal is increasing. With the development of communication technology, various types of services such as Bluetooth, WLAN, GPS, and DMB are provided in addition to general CDMA / GSM communication, and the demand for convergence terminals that accommodate such services in one terminal is expected to increase in the future. .

1 is a diagram illustrating a transmission line structure for feeding power to a plurality of antennas in a conventional convergence terminal.

1 illustrates a structure for transmitting an RF signal using a coaxial cable among various transmission lines.

As shown in FIG. 1, when the terminal provides mobile communication (GSM / CDMA), Bluetooth, and GPS communication services, there are coaxial cables for providing mobile communication (GSM / CDMA), Bluetooth, and GPS signals, respectively. .

The first coaxial cable 500 is a coaxial cable for feeding a Bluetooth signal and is connected to the Bluetooth antenna 110, and the second coaxial cable 502 is a coaxial cable for feeding a GPS signal and is electrically connected to the GPS antenna 112. The third coaxial cable 504 is a coaxial cable for feeding mobile communication signals (GSM / CDMA).

As illustrated in FIG. 1, there has been a conventional problem in that a plurality of transmission lines are provided for transmission of respective communication signals.

As such, when a plurality of transmission lines is provided, the transmission lines have to occupy a lot of space in the terminal, and thus there is a problem that the miniaturization of the terminal is prevented. In addition, as the terminal becomes smaller, elements such as batteries or speakers of the terminal frequently interfere with the path of the transmission line, and transitions are made several times in order to avoid path interruption of the speaker or battery and the grounded element. There was this.

In the present invention, to solve the problems of the prior art as described above, it is proposed a single transmission line for a multi-antenna feed that can provide a signal for a plurality of antennas by a single structure.

Another object of the present invention is to propose a single transmission line for a multi-antenna power supply suitable for implementing a terminal in a small size.

Other objects of the present invention may be derived by those skilled in the art through the following examples.

In order to achieve the above object, in accordance with an aspect of the present invention, a flexible PCB; A plurality of signal patterns formed on the flexible PCB and to which an RF signal is applied; And a plurality of ground patterns formed on the flexible PCB and electrically connected to ground, wherein the plurality of signal patterns and ground patterns are alternately formed in parallel, and the plurality of signal patterns respectively supply RF signals to different antennas. A single transmission line for multiple antenna feeding is provided.

 The plurality of ground patterns may be formed at left and right sides of each of the plurality of signal patterns.

According to another aspect of the present invention, a plurality of ground patterns and signal patterns formed on the same plane-the plurality of signal patterns and ground patterns are formed alternately in parallel and the plurality of signal patterns are each RF signal to a different antenna Feeder-; An upper ground pattern disposed on an upper portion of the plurality of signal patterns and the ground pattern, the upper ground pattern being electrically connected to the ground; And a lower ground pattern disposed below and spaced apart from the plurality of signal patterns and the ground pattern by a predetermined distance and electrically connected to the ground.

The plurality of ground patterns may be formed at left and right sides of each of the plurality of signal patterns.

The above-described transmission line includes: a first substrate on which the lower ground pattern is formed; A second substrate stacked on the first substrate and having the plurality of signal patterns and side ground patterns formed thereon; And a third substrate stacked on the second substrate and having the upper ground pattern formed thereon.

Preferably, the first to third substrates are flexible PCBs.

The plurality of signal patterns, side ground patterns, upper ground patterns, and lower ground patterns may be formed on a flexible multilayer PCB having a plurality of layers.

The lower ground pattern is formed on a predetermined first layer of the flexible multilayer PCB, and the plurality of signal patterns and ground patterns are formed on a predetermined second layer existing on the first layer, and the upper ground is formed. The pattern may be formed on a predetermined third layer existing on the second layer.

The present invention can provide a signal for a plurality of antennas by a single structure, and there is an advantage suitable for implementing a terminal in a small size.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of a single transmission line for a multi-antenna power supply according to the present invention in detail.

2 is a diagram illustrating a plan view of a single transmission line for multiple antennas according to an embodiment of the present invention.

2, a single transmission line for a multi-antenna power supply according to an exemplary embodiment of the present invention may include a substrate 200, a first ground pattern 202, a first signal pattern 204, and a second ground pattern 206. The second signal pattern 208 and the third ground pattern 210 may be included.

The substrate 200 is a dielectric material and functions as a body of a transmission line. Various dielectric materials may be applied, and for example, a Teflon substrate, a ceramic substrate, a glass epoxy substrate, or the like may be used. According to a preferred embodiment of the present invention, the substrate 200 is preferably a flexible PCB.

As portable terminals become smaller and smaller, spaces in which transmission lines can be installed in a straight line are often not secured. For example, a transmission line directed to a certain direction may be blocked by large elements such as a battery and a speaker. Therefore, it is preferable to use a flexible PCB to solve such a problem.

The first ground pattern 202 and the second ground pattern 206 are electrically connected to the ground in the terminal and are coplanar with the first signal pattern 204 and the second signal pattern 208.

The first ground pattern 202 and the second ground pattern 206 are ground patterns for guiding the RF signal provided to the first signal pattern 204 and the first signal pattern 204 and the first ground pattern 202. And the second ground pattern 206 has the form of the same planar transmission line (CPW).

A first RF signal having a first frequency may be applied to the first signal pattern 204, and for example, a Bluetooth signal may be applied to the first signal pattern 204. The first signal pattern proceeds in a direction parallel to the first ground pattern 202 and the second ground pattern 204 and is bent to be electrically coupled with the Bluetooth antenna at a predetermined point.

Since the first signal pattern 204 is bent at a predetermined point for coupling with the Bluetooth antenna, the first ground pattern 202 is formed shorter than the first signal pattern 204.

Of course, when the location of the Bluetooth antenna is not the side portion of the substrate 200 as shown in FIG. 2, the first signal pattern 204 may be formed to be straight without being bent like the second signal pattern 208.

The third ground pattern 210 is for an RF signal applied to the second signal pattern 208 together with the second ground pattern 206.

A second RF signal having a second frequency may be applied to the second signal pattern 208. For example, a CDMA mobile communication signal may be applied to the second signal pattern 208. The end of the second signal pattern is coupled with the CDMA antenna.

That is, according to the present invention, a plurality of signal patterns and ground patterns may be alternately formed on a single substrate, and thus power may be supplied to the plurality of antennas by a transmission line formed on the single substrate.

FIG. 2 illustrates a case in which two signal patterns and three ground patterns are formed so that feeding of two antennas is performed by a single transmission line, but the ground pattern and the signal pattern are alternately formed on the same plane. It will be apparent to those skilled in the art that the transmission line can be designed to enable feeding of three or more antennas accordingly.

3 is a diagram illustrating a cross-sectional view when a single transmission line for multiple antennas is mounted in a terminal according to an embodiment of the present invention.

As described above, the substrate 300 of the single transmission line according to the embodiment of the present invention is preferably implemented as a flexible PCB. As shown in FIG. 3, when a plurality of signal patterns and ground patterns are formed on the flexible PCB, the flexible PCB can be bent even if the transmission direction of the transmission line is blocked by the battery, thereby enabling stable without having a transition even in a small terminal. Feeding is possible.

4 is a diagram illustrating a cross-sectional view of a single transmission line for a multi-antenna power supply according to another embodiment of the present invention, and FIG. 5 is an exploded perspective view of the single transmission line for a multi-antenna power supply shown in FIG. 4.

4 and 5, the single transmission line for the multi-antenna power supply according to another embodiment of the present invention is formed on the first substrate 450, the lower ground pattern 410 formed on the first substrate 450, and the first transmission line. A plurality of ground patterns 400, 404, 408 and signal patterns 402, 406, a third substrate 454, and a third substrate formed on the second substrate 452 and the second substrate 452. The upper ground pattern 412 may be included.

 4 and 5 illustrate a structure in which the ground pattern is additionally provided on the upper and lower portions of the planar transmission line shown in FIG. 2.

4 and 5 is a structure for minimizing the loss of the transmission line compared to the embodiment shown in FIG.

The first to third substrates 450, 452, and 454 on which the conductive patterns are formed are preferably flexible PCBs.

According to an embodiment of the present invention, the first to third substrates may be a single layer flexible PCB, and may be implemented in a form in which the single layer flexible PCBs are stacked.

According to another embodiment of the present invention, the first substrate to the third substrate may be a multilayer flexible PCB, and the first substrate to the third substrate may be a specific layer of the multilayer flexible PCB.

Since the second substrate 452, the signal patterns 402 and 406 and the ground patterns 400, 404 and 408 formed on the second substrate are the same as those of the embodiment of FIG. 2, a detailed description thereof will be omitted. do.

The transmission line of the second substrate is an extension of the CPW transmission line. Since the transmission line of this structure is a structure in which some of the RF signals can escape upward and downward, relatively large radiation loss may occur, and in the high frequency band Return loss can also occur.

4 and 5, the upper and lower ground patterns 412 and the lower ground patterns may be spaced apart from the signal pattern 400 by a predetermined distance on the upper and lower portions of the second substrate 452 to solve this problem. 410 is additionally provided.

4 and 5 illustrate a structure in which a ground pattern is provided at both the upper and lower portions of the signal pattern, but a structure in which the ground pattern is formed at only one of the upper and lower portions may also be included in the scope of the present invention.

According to a more preferred embodiment of the present invention, a multilayer flexible PCB may be used to implement the transmission line of the multilayer structure shown in FIGS. 4 and 5.

The multi-layer flexible PCB is a PCB formed by stacking a plurality of sub layers, and is manufactured by stacking and stacking a single substrate. Multi-layer PCB is mainly used to enlarge the wiring area, and the connection between the wires formed in each layer is made through via holes. Since multi-layer PCB has a structure of stacking multiple layers, matching to align each layer in place is important, and matching methods include pin matching and mass matching.

Such a multi-layer flexible PCB can be effectively used to implement the transmission line of the present invention, and does not require via connection because there is no electrical connection between the patterns formed in each layer. Can be implemented.

For example, when a flexible multilayer PCB including seven layers is used, a lower ground pattern 410 may be formed on the first layer at the bottom of the flexible multilayer PCB. In addition, signal patterns 402 and 406 and side ground patterns 400, 404 and 408 may be formed in a fourth layer of the flexible multilayer PCB. The upper ground pattern 412 is a flexible multilayer to equalize the separation distance between the lower ground pattern 412 and the signal patterns 402 and 404 and the separation distance between the upper ground pattern 410 and the signal patterns 402 and 406. It may be formed on the seventh layer of the PCB.

When implementing the transmission line of the present invention using a flexible multilayer PCB, the separation distance between the signal patterns 402 and 406 and the upper and lower ground patterns 410 and 412 can be adjusted by appropriately selecting the layer on which the pattern is formed. have.

In the above, an embodiment of implementing a transmission line having a multi-layer structure using a plurality of substrates or a multilayer PCB has been described. However, the present invention is not limited thereto, and the embodiment illustrated in FIGS. 4 and 5 will be described using various elements. It will be understood by those skilled in the art that they can be implemented.

FIG. 6 is a diagram illustrating a single transmission line structure for feeding power to three antennas.

2, 4, and 5 show a pattern structure for feeding two antennas, whereas FIG. 6 shows a structure in which a signal pattern and a ground pattern are additionally provided for the pattern structure of three antennas. .

As in the above-described embodiments, the ground patterns 600, 604, 608, and 612 and the signal patterns 602, 606, and 610 are alternately formed.

As shown in FIG. 6, three additional antennas may be fed when the third signal pattern 610 and the third ground pattern 612 are formed, and three additional signal patterns and the ground pattern may be provided. Power supply to the above antenna is possible.

 Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the present invention without departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that it can be changed.

1 is a diagram illustrating a structure of a transmission line for feeding power to a plurality of antennas in a conventional convergence terminal.

2 is a plan view of a single transmission line for a multi-antenna power supply according to an embodiment of the present invention.

3 is a cross-sectional view when a single transmission line for a multi-antenna power supply is mounted to a terminal according to an embodiment of the present invention.

4 is a cross-sectional view of a single transmission line for multiple antennas according to another embodiment of the present invention.

FIG. 5 is an exploded perspective view of a single transmission line for multiple antenna feeding shown in FIG. 4; FIG.

FIG. 6 illustrates a structure of a single transmission line for feeding three antennas. FIG.

Claims (8)

Flexible PCB; And A plurality of signal patterns formed on the flexible PCB and to which an RF signal is applied; Includes a plurality of ground patterns formed on the flexible PCB and electrically connected to the ground, And the plurality of signal patterns and ground patterns are alternately formed in parallel, and the plurality of signal patterns respectively feed RF signals to different antennas. The method of claim 1, The plurality of ground patterns are formed on the left and right of each of the plurality of signal patterns, a single transmission line for multiple antennas. A plurality of ground patterns and signal patterns formed on the same plane, wherein the plurality of signal patterns and ground patterns are alternately formed in parallel and the plurality of signal patterns respectively feed RF signals to different antennas; An upper ground pattern disposed on an upper portion of the plurality of signal patterns and the ground pattern, the upper ground pattern being electrically connected to the ground; And a lower ground pattern disposed below and spaced apart from the plurality of signal patterns and the ground pattern by a predetermined distance and electrically connected to the ground. The method of claim 3, The plurality of ground patterns are formed on the left and right of each of the plurality of signal patterns, a single transmission line for multiple antennas. The method of claim 3, A first substrate on which the lower ground pattern is formed; A second substrate stacked on the first substrate and having the plurality of signal patterns and side ground patterns formed thereon; And And a third substrate stacked on the second substrate and having the upper ground pattern formed thereon. The method of claim 5, The first substrate to the third substrate is a flexible PCB, characterized in that the flexible PCB. The method of claim 5, And the plurality of signal patterns, side ground patterns, upper ground patterns, and lower ground patterns are formed on a flexible multilayer PCB having a plurality of layers. The method of claim 7, wherein The lower ground pattern is formed on a predetermined first layer of the flexible multilayer PCB, and the plurality of signal patterns and ground patterns are formed on a predetermined second layer existing on the first layer, and the upper ground is formed. And a pattern is formed on the predetermined third layer existing on the second layer.

Images