KR101421141B1 - Printed circuit board for log-periodic dipole array antenna and integrated system for the same - Google Patents

Abstract

The present invention provides a printed circuit board for an airborne periodic dipole array (LPDA) antenna and an integrated system for an LPDA antenna comprising the same. In particular, the printed circuit board for the LPDA antenna comprises a first terminal and a second terminal respectively connected to the LPDA antenna; An RF transformer for impedance matching of the LPDA antenna; And a plurality of passive elements including a first capacitor connected between one side of the RF transformer and the first terminal and a second capacitor connected between one side of the RF transformer and the second terminal, Each of the second terminals is connected to a first line body and a second line body of the LPDA antenna arranged at a predetermined interval and the other end of the RF transformer is connected to a signal analyzing part for analyzing a signal radiated from the LPDA antenna And the ground terminal.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a printed circuit board (PCB) and an integrated system for a logarithmic periodic dipole array (LPDA)

The present invention relates to a printed circuit board and an integrated system for a logarithmic periodic dipole array (LPDA) antenna, and more particularly to a printed circuit board for a logarithmic periodic dipole array (LPDA) antenna installed at an airport and an integrated system therefor will be.

The localizer (LLZ) is a device that sends a signal about the position azimuth angle to the aircraft side so that the aircraft can maintain horizontal position with respect to the center line of the runway in the airport. Generally, 90Hz and 150Hz modulated signals are transmitted to the center line of the runway And radiates through the directional antenna as shown in Figs. 1 and 2 in the lateral direction. FIGS. 1 and 2 are diagrams for explaining a modulation signal radiated from an azimuth angle localizer. FIG.

At this time, since the amplitude of the modulated signal radiated in the left and right direction is equal to each other, the aircraft can check the left and right inclination state of the aircraft by comparing the magnitudes of the received modulated signals.

The LLZ antenna is a directional VHF antenna interlocked with the above-mentioned azimuth angle device, and mainly uses a log-periodic dipole array (LPDA) type antenna. 3 is a diagram showing the outer shape of an algebraic periodic dipole array (LPDA) antenna. The LPDA antenna 100 is a broadband antenna having a structure in which the impedance and the radiation characteristic with respect to frequency are periodically repeated with respect to the logarithmic value of the frequency. That is, there is almost no change in characteristics of the antenna between the operating frequency bands.

In addition, the length and spacing of the multiple dipole elements 120 forming the LPDA antenna 100 are generally increased at a constant rate, and the phase difference between the dipole elements 120 is 180 degrees. The impedance of the LPDA antenna 100 can be determined by the impedance of the feed line and the thickness of the dipole, and is generally designed to be 50 ohms. The radiation pattern of the LPDA antenna 100 is designed to eliminate and minimize mutual coupling between the dipole elements 120. [ In addition, the LPDA antenna 100 includes a first line body 110a and a second line body 110b arranged in parallel with each other at a predetermined interval, and the first line body 110a and the second line body 110b, A plurality of dipole elements 120 are formed on the two-line body 110b.

In this regard, Korean Patent Laid-Open Publication No. 2008-0044788 entitled " Algebraic Periodic Dipole Array (LPDA) Antenna (LPDA) Antenna and Method of Manufacturing the Same) " includes a first antenna element, a second antenna element and a pair of transmission line structures Discloses a structure of an LPDA antenna and a method of manufacturing the same.

Meanwhile, an LPDA antenna used for an instrument landing system (ILS) at an airport generally forms a balanced (balun to unbalanced) antenna using an RF cable 10 as shown in FIG. 4 is a view for explaining a balun formed with an RF cable.

Specifically, the balun converts a balanced signal to an unbalanced signal or an unbalanced signal to a balanced signal. For example, if each signal is transmitted through two parallel metals in a balanced state, then one of the two metals is grounded and the signal carrying all the information is transmitted through the other, have. In monitoring the signal radiated from the LPDA antenna, the RF cable 10 is used as a balun having a phase of about 180 degrees as shown in FIG. 4, and one coupling output port (Couple output) And a signal analyzing unit 600 may be connected. That is, the RF cable 10 operates as a balun and performs an operation for impedance matching. For reference, A shown in FIG. 4 is a portion in which the power feed terminal 510 shown in FIG. 7 is disposed.

However, if the balun is constructed in such a manner, the coupling output port is impedance mismatched with the RF cable 10 or the signal analyzer 600, which is a 50? System, so that not only a loss occurs in the line, The quality of the signal for monitoring transmitted to the analyzer 600 may be degraded.

Meanwhile, FIG. 5 is a view showing a component that is soldered for feeding the LPDA antenna. Conventionally, the parts are directly soldered to the feed line connection parts as shown in FIG. 5 to adjust impedance and adjust the phase. This causes inconvenience, time consumption and instability.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the conventional art described above, and it is an object of the present invention to provide an impedance matching method and an impedance matching method in which a circuit constituting a balun is mounted on a printed circuit board in advance, And an object of the present invention is to provide a printed circuit board for an LPDA antenna installed at an airport that can improve system performance.

It is to be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

According to an aspect of the present invention, there is provided a printed circuit board for an LPDA antenna installed at an airport, comprising: a first terminal connected to an LPDA antenna; Two terminals; An RF transformer for impedance matching of the LPDA antenna; And a plurality of passive elements including a first capacitor connected between one side of the RF transformer and the first terminal and a second capacitor connected between one side of the RF transformer and the second terminal, Each of the second terminals is connected to a first line body and a second line body of the LPDA antenna arranged at a predetermined interval and the other end of the RF transformer is connected to a signal analyzing part for analyzing a signal radiated from the LPDA antenna And the ground terminal.

Further, an integrated system for a logarithmic periodic dipole array (LPDA) antenna installed at an airport according to another embodiment of the present invention includes an LPDA including a first line body and a second line body disposed in parallel at predetermined intervals, A printed circuit board connected to the antenna; A coupling bar connected to the printed circuit board to transmit a signal radiated from the LPDA antenna; A wave distribution unit connected to the LPDA antenna to supply a radio wave; And a signal analyzer for monitoring and analyzing signals received from the coupling bar, wherein the printed circuit board includes a first terminal and a second terminal respectively connected to the first line body and the second line body; An RF transformer for impedance matching of the LPDA antenna; And a plurality of passive elements including a first capacitor connected between one side of the RF transformer and the first terminal and a second capacitor connected between one side of the RF transformer and the second terminal, Is connected to the signal analysis unit and the ground terminal, respectively.

According to the above-mentioned object of the present invention, a balun is constructed by mounting and connecting components including a first terminal, a second terminal, an RF transformer, and a plurality of passive elements having a previously designed connection relationship, The impedance matching can be easily performed at the same time, and the performance of the overall system can be improved.

According to the above-mentioned object of the present invention, it is possible to secure the accuracy and convenience of impedance matching, to transmit a signal radiated from the LPDA antenna to a signal analysis unit in a high quality state, Can be made more precisely.

FIGS. 1 and 2 are diagrams for explaining a modulation signal radiated from an azimuth angle localizer. FIG.
3 is a diagram showing the outer shape of an algebraic periodic dipole array (LPDA) antenna.
4 is a view for explaining a balun formed with an RF cable.
FIG. 5 is a view showing a component in which soldering is performed for feeding the LPDA antenna. FIG.
FIG. 6 is a block diagram of an integrated system for an LPDA antenna according to an embodiment of the present invention. Referring to FIG.
FIG. 7 is an enlarged view of the panel 400 shown in FIG.
FIG. 8 is a block diagram specifically illustrating a printed circuit board for an LPDA antenna according to an embodiment of the present invention. Referring to FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

FIG. 6 is a block diagram of an integrated system for an LPDA antenna according to an embodiment of the present invention. Referring to FIG.

Referring to FIG. 6, an integrated system for an LPDA antenna according to an embodiment of the present invention includes an LPDA antenna 100, a printed circuit board 200, a coupling bar 300, a panel 400, And a control / processing system including an Antenna Distribution Unit (ADU) 500 and a Combining & Monitoring Unit (CMU) 600.

The LPDA antenna 100 should be capable of being applied to an instrument landing system (ILS) used primarily at airports and should be able to help guide the landing of an airplane. The LPDA antenna 100 includes a first line body 110a and a second line body 110b which are arranged in parallel with each other at a predetermined interval as described above and the first line body 110a and the second line body 110b, A plurality of dipole elements 120 are formed on the two-line body 110b. Here, the arrangement, the length, and the like of the dipole element 120 are not particularly limited.

The printed circuit board 200 includes a side connected to the LPDA antenna 100 and a side connected to a coupling bar 300 to be described later, which will be described later.

The coupling bar 300 is disposed on both sides of the LPDA antenna 100 in the longitudinal direction of the LPDA antenna 100 and outputs a power sampled signal of signals radiated from the LPDA antenna 100 to a signal analysis Unit 600 as shown in FIG. One end of the coupling bar 300 is connected to the printed circuit board 200 and the other end of the coupling bar 300 is connected to the signal analyzer 600. The other end of the coupling bar 300 is connected to the coupling bar 300 by the RF cable 310 have. Although the coupling bar 300 is shown as a long bar in FIG. 6, the coupling bar 300 is not particularly limited as long as it can effectively transmit a signal radiated from the LPDA antenna 100 or a part of the signal.

A panel 400 as shown in FIG. 7 may be disposed outside the control / processing system. FIG. 7 is an enlarged view of the panel 400 shown in FIG. A power feeding terminal 510 used for feeding a radio wave to the LPDA antenna 100 on the panel 400 and a monitoring terminal 610 used for monitoring a signal radiated from the LPDA antenna 100 . That is, the power feed terminal 510 can transmit a radio wave received from the radio wave distributor 500 to the LPDA antenna 100, and the monitoring terminal 610 can perform signal analysis on the signal transmitted through the coupling bar 300 Unit 600 as shown in FIG.

The radio frequency distribution unit 500 is connected to the LPDA antenna 100 to feed the radio wave through the power supply terminal 510. It is necessary to transmit radio waves having different phases and amplitudes to the respective LPDA antennas 100 because the number of the LPDA antennas 100 installed at the airport may be 20 or more and the number of the respective dipole elements may be different. The radio frequency distribution unit 500 can distribute the four modulated amplified signals to the respective antennas according to predetermined amplitudes and phases. At this time, the four modulated amplified signals may be a Course CSB signal, a Course SBO signal, a Clearance CSB signal, and a Clearance SBO signal . In addition, the radio wave distribution section 500 may perform a cable fault monitoring function.

The signal analyzer 600 monitors and analyzes the coupled signal after passing through the coupling bar 300 and the monitoring terminal 610. Specifically, the signal analyzer 600 may combine the received signals and generate three signals from the combined signals. These signals may be a Course Line, a Course Sector, or a Clearance. The signal analyzer 600 can adjust the phase of the combined signal as needed.

Meanwhile, each of the components shown in FIG. 6 may be configured as a 'module'. The term 'module' refers to a hardware component such as software or a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), and the module performs certain roles. However, a module is not limited to software or hardware. A module may be configured to reside on an addressable storage medium and may be configured to execute one or more processors. The functionality provided by the components and modules may be combined into a smaller number of components and modules or further separated into additional components and modules.

Hereinafter, the printed circuit board 200 will be described with reference to FIG. FIG. 8 is a block diagram specifically illustrating a printed circuit board for an LPDA antenna according to an embodiment of the present invention. Referring to FIG.

The printed circuit board 200 for the LPDA antenna according to an embodiment of the present invention can be used only for the LPDA antenna 100 installed at an airport and includes a first terminal 211, a second terminal 212, an RF A transformer 220, and a component including a plurality of passive elements.

The first terminal 211 is connected to the first line body 110a of the LPDA antenna 100 and the second terminal 212 is connected to the second line body 110b of the LPDA antenna 100. [ As described above, the LPDA antenna 100 includes a first line body 110a and a second line body 110b. At this time, each of the first terminal 211 and the second terminal 212 can receive a coupling signal from the LPDA antenna.

The RF transformer 220 performs impedance matching of the LPDA antenna 100. One side of the RF transformer 220 is connected to the first terminal 211 and the second terminal 212 and the other side of the RF transformer 220 is connected to a signal analyzer 600 and the ground terminal, respectively.

8, a first capacitor 231 is connected between one side of the RF transformer 220 and the first terminal 211, and a first capacitor 231 is connected between one side of the RF transformer 220 and the second terminal 212. In other words, And a third capacitor 233 may be connected between the other side of the RF transformer 220 and the signal analyzer 600. [ The third capacitor 233 may be connected to the monitoring terminal 610 disposed on the coupling bar 300 or the panel 400 described above.

Further, a large number of windings may be wound on the other side of the RF transformer 220 than one side of the RF transformer 220. That is, the number of windings on one side of the RF transformer 220 may be smaller than that on the other side of the RF transformer 220. For example, the ratio of the primary and secondary windings of the RF transformer 220 may be 1: 4. The characteristic impedance of the coupling bar side (load side) of the LPDA antenna 100 is measured to be about 1.7 + j2.4, and can be expressed by Equation 1 below.

Therefore, based on equation (2), the output side can achieve impedance matching with a 50 ohm system, and the ambient influence can be minimized by using passive elements such as R (resistance), L (coil), and C (capacitor).

In other words, the plurality of passive elements are mounted on the printed circuit board 200 with a pre-designed connection relationship. For example, the passive elements may include the first, second, and third capacitors 231, 232, and 233 described above.

The printed circuit board for the logarithmic periodic dipole array (LPDA) antenna described above is installed at an airport and mounts a component including a first terminal, a second terminal, an RF transformer and a plurality of passive elements, As shown in FIG. With this configuration, it is possible to easily perform the impedance matching while configuring the balun and improve the performance of the overall system.

In addition, the integrated system for LPDA antennas can ensure the accuracy and convenience of impedance matching, and can transmit the signal emitted from the LPDA antenna to the signal analysis section in high quality state, and perform the second processing and analysis more precisely can do.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

200: printed circuit board 211: first terminal
212: second terminal 220: RF transformer
231: first capacitor 232: second capacitor
233: third capacitor

Claims (6)

A printed circuit board for an airborne periodic dipole array (LPDA) antenna installed at an airport,
A first terminal and a second terminal respectively connected to the LPDA antenna;
An RF transformer for impedance matching of the LPDA antenna; And
A plurality of passive elements including a first capacitor connected between one side of the RF transformer and the first terminal, and a second capacitor connected between one side of the RF transformer and the second terminal,
Wherein the first terminal and the second terminal are connected to a first line body and a second line body of the LPDA antenna arranged at a predetermined interval,
And the other side of the RF transformer is connected to a signal analyzer and a ground terminal for analyzing signals emitted from the LPDA antenna.
The method according to claim 1,
And a third capacitor connected between the other side of the RF transformer and the signal analysis unit.
The method according to claim 1,
Wherein the number of windings on one side of the RF transformer is less than the number of turns on the other side of the RF transformer.
An integrated system for an algebraic periodic dipole array (LPDA) antenna installed at an airport,
A printed circuit board connected to an LPDA antenna including a first line body and a second line body disposed in parallel at predetermined intervals;
A coupling bar connected to the printed circuit board to transmit a signal radiated from the LPDA antenna;
A wave distribution unit connected to the LPDA antenna to supply a radio wave; And
And a signal analyzer for monitoring and analyzing signals received from the coupling bar,
The printed circuit board
A first terminal and a second terminal respectively connected to the first line body and the second line body;
An RF transformer for impedance matching of the LPDA antenna; And
A plurality of passive elements including a first capacitor connected between one side of the RF transformer and the first terminal, and a second capacitor connected between one side of the RF transformer and the second terminal,
And the other end of the RF transformer is connected to the signal analyzer and the ground terminal, respectively.
5. The method of claim 4,
The printed circuit board
And a third capacitor connected between the other side of the RF transformer and the signal analysis unit.
5. The method of claim 4,
Wherein the number of windings on one side of the RF transformer is less than the number of turns on the other side of the RF transformer.

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