A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument

Abstract

This invention discloses a radiating antenna for testing the directional function of an ultra-shortwave directional instrument. It includes a metal outer shell, a metal inner shell, an upper dielectric substrate, a lower dielectric substrate, a directional radiating antenna, a handle, and an antenna control switch. The metal inner shell is housed within the metal outer shell. The upper and lower dielectric substrates are arranged along the upper edge of the inner shell. Eight annular metal strips are evenly distributed within the dielectric substrate interlayer. A metal feed line is connected to the same side of each annular metal strip. Each annular metal strip and its connected metal feed line constitute a directional radiating antenna. The eight directional radiating antennas provide radio frequency azimuth signals in eight directions: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°. A handle is located on the side of the metal outer shell. This invention achieves the output of radio frequency signals in eight azimuth angles by accessing signals from different feed lines, enabling close-range testing of the directional function of the ultra-shortwave directional instrument antenna, while simultaneously optimizing the frequency band performance of the radiating antenna.

Description

Technical Field

[0001] This invention relates to the field of aircraft testing technology, and in particular to a radiating antenna for testing the directional function of a VHF directional instrument. It can be used with general-purpose instruments such as standard signal generators to achieve close-range testing and verification of the directional function of a VHF directional instrument. Background Technology

[0002] To verify the directional performance of the VHF / UHF directional instrument, testing personnel must perform functional checks, performance index verification, and troubleshooting before installation. The directional performance test of the instrument is a quantitative test of its directional accuracy, equivalent sensitivity, blocking level, and other performance indicators. It is a crucial measurement method for ensuring the stable and normal operation of the VHF / UHF directional instrument. In previous airborne VHF / UHF directional function checks, to improve measurement accuracy and ensure the accuracy of the results, the instrument's signal reception required that it meet the requirements of long-distance space waves in the external field; that is, the transmitted signal was tested using a long-distance feed method. However, in actual testing environments, using long-distance space feed measurements has certain drawbacks and uncertainties, specifically:

[0003] (1) The accuracy of the test is difficult to guarantee. There are many interference factors in the open space environment. Clutter and interference signals will place high demands on the receiving power and receiver sensitivity of the directional instrument, resulting in high uncertainty of the test results.

[0004] (2) The measurement efficiency is low, and the layout and selection of the field site will take up most of the test process time;

[0005] (3) During indirect measurement, when electromagnetic radiation is measured using a space antenna radiation method, the electromagnetic radiation will be completely exposed to the space, and electromagnetic radiation leakage and personnel injury are unavoidable.

[0006] With the continuous development of airborne testing technology, miniaturization, lightweighting, and modularization have become the development direction of airborne equipment testing technology. This means that the testing methods that previously relied on long-distance space wave radiation measurement directional instruments need to be improved. Given the shortcomings of the above testing technologies, a short-range testing device needs to be designed. This device should possess short-range directional instrument testing capabilities and should feature high efficiency, high precision, high compatibility, high reliability, small footprint, easy installation, and portability. Its core component, the radiating antenna, should exhibit short-range multi-azimuth radiation characteristics, meeting the requirements of small antenna design, and possess a cardioid radiation pattern. Summary of the Invention

[0007] To address the aforementioned issues, this invention provides a radiating antenna for testing the directional function of a direction finder. Using the radiating antenna as its core component reduces the design complexity of the RF front-end of the testing device, provides short-range testing capabilities, eliminates the need for an outdoor testing environment, and incorporates an impedance matching device at one end of the feed line to ensure RF transmission characteristics. This reduces the harm to testing personnel from leaked electromagnetic radiation and guarantees transmission performance.

[0008] A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument includes a metal outer shell, a metal inner shell, an upper dielectric substrate, a lower dielectric substrate, a directional radiating antenna, a handle, and an antenna control switch. A circular opening is formed on the upper surface of the metal outer shell, within which a basin-shaped metal inner shell is housed. A step difference is established between the upper surfaces of the metal outer shell and the metal inner shell. The upper and lower dielectric substrates are positioned along the upper edge of the metal inner shell. Eight annular metal strips are evenly distributed along the outer edge of the dielectric substrate within the interlayer between the upper and lower dielectric substrates. Each annular metal strip is connected to the same side... It is equipped with a metal feed line that passes through the gap between the double-layer dielectric substrate and the metal inner shell. The metal feed line is connected to the antenna control switch located at the bottom of the metal inner shell along the outer surface of the metal inner shell. Each ring-shaped metal strip and the metal feed line connected to it form a directional radiation antenna. The eight directional radiation antennas provide radio frequency azimuth signals in eight directions: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°. A handle is provided on the side of the metal outer shell. Power cable passage holes and test instrument cable passage holes are provided at the bottom of both sides of the metal outer shell.

[0009] The inner and outer surfaces of the metal casing are flat and smooth. The metal casing is equipped with metal support columns inside, and the inner casing is connected and fixed to the metal support columns by screws. The metal casing is connected to the power supply and external test instruments through power cable through holes and test instrument cable through holes to realize power supply and control.

[0010] The joint between the inner and outer metal shells is uniform and flat, and the inner and outer walls of the cavity are flat and smooth. The upper surface has screw holes for connection and fixation with the outer metal shell.

[0011] The upper and lower dielectric substrates are made of white FR-4 epoxy resin boards, and an annular metal strip is etched on the lower dielectric substrate.

[0012] The metal feed line is a parallel double-conductor copper wire with a characteristic impedance of 50 ohms and an outer layer of insulating material. One end of the metal feed line is connected to the annular metal strip by solder through holes on the side of the metal inner shell and the gap of the dielectric substrate. The other end of the metal feed line is connected to the antenna control switch.

[0013] Beneficial effects of the invention: This invention relates to a method and a radiating antenna structure for close-range inspection of the directional function of an ultra-shortwave directional instrument antenna. Using the radiating antenna as the core component reduces the design complexity of the RF front-end of the testing device, provides close-range testing capabilities, eliminates the need for an outdoor testing environment, and reduces the harm to testing personnel from electromagnetic radiation leakage. This device features high efficiency, high precision, high compatibility, high reliability, small footprint, easy installation, and portability. Its core component, the directional radiating antenna, meets transmission impedance matching conditions and exhibits close-range multi-azimuth radiation characteristics. The antenna is an array radiating antenna placed at the cavity opening of a metal inner shell structure. Through the control of the excitation source and antenna control switch, different azimuth radiating signals are simulated to radiate test signals at different angles during the directional function testing of the ultra-shortwave directional instrument. These test signals are received by the directional antenna of the ultra-shortwave directional instrument, processed, and the azimuth angle is displayed. Readings are measured in each direction, thereby obtaining the main technical indicators such as the directional accuracy of the ultra-shortwave directional instrument. Attached Figure Description

[0014] Figure 1 Overall outline of a radiating antenna for testing the directional function of an ultra-shortwave directional instrument. Figure 2 Internal structure diagram of a radiating antenna used for directional function testing of an ultra-shortwave directional instrument Figure 3 Top view of the internal structure of a radiating antenna for detecting the directional function of an ultra-shortwave directional instrument.

[0015] Figure 4 Left view of the internal structure of a radiating antenna used for directional function testing of an ultra-shortwave directional instrument.

[0016] The numbers in the diagram are explained as follows: 1. Metal inner shell; 2. Upper dielectric plate; 3. Annular metal strip; 4. Metal feeder; 5. Metal outer shell; 6. Lower dielectric plate; 7. Handle; 8. Power through hole; 9. Cable through hole; 10. Metal support column. Detailed Implementation

[0017] The directional radiation antenna in this invention is the core component of the testing equipment. It is mainly used to radiate radio frequency signals in different directions. It can provide radio frequency directional signals in eight directions: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°.

[0018] like Figure 1-4As shown, a radiating antenna for detecting the directional function of an ultra-shortwave directional instrument includes a metal outer shell 5, a metal inner shell 1, an upper dielectric substrate 2, a lower dielectric substrate 6, a directional radiating antenna, a handle 7, and an antenna control switch. A circular opening is formed on the upper surface of the metal outer shell 6, and a basin-shaped metal inner shell 1 is disposed within the circular opening. A step difference is provided between the upper surfaces of the metal outer shell 6 and the metal inner shell 1. The upper dielectric substrate 2 and the lower dielectric substrate 6 are disposed along the upper edge of the metal inner shell 1. Eight annular metal strips 3 are evenly distributed along the outer edge of the dielectric substrate within the interlayer between the upper and lower dielectric substrates 2 and 6. Each annular metal strip 3... A metal feed line 4 is connected to one side. The metal feed line 4 passes through the gap between the double-layer dielectric plates and the metal inner shell 1. It is connected to the antenna control switch at the bottom of the metal inner shell 1 along the outer surface of the metal inner shell 1. Each ring-shaped metal strip 3 and the metal feed line 4 connected to it form a directional radiation antenna. The eight directional radiation antennas provide radio frequency directional signals in eight directions: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°. A handle 7 is provided on the side of the metal outer shell 5. Power cable passage holes 8 and test instrument cable passage holes 9 are provided at the bottom of both sides of the metal outer shell 5.

[0019] The inner and outer surfaces of the metal outer casing 5 are flat and smooth. A metal support column 10 is installed inside the metal outer casing 5. The metal inner casing 1 is connected and fixed to the metal support column 10 by screws. The metal outer casing 6 is connected to the power supply and external test instruments through the power cable through hole 8 and the cable through hole 9 of the test instrument to realize power supply and control.

[0020] The joint between the inner metal shell 1 and the outer metal shell is uniform and flat. The inner and outer surfaces of the cavity are flat and smooth. The upper surface has screw holes for connecting and fixing with the outer metal shell 5.

[0021] The upper dielectric substrate 2 and the lower dielectric substrate 6 are made of white FR-4 epoxy resin boards, and an annular metal strip is etched on the lower dielectric substrate.

[0022] The metal feed line 4 is a parallel double-wire copper metal wire with a characteristic impedance of 50 ohms and an outer layer of insulating material. One end of the metal feed line 4 is connected to the directional radiation antenna by solder through the holes on the side of the metal inner shell 5 and the gap of the dielectric board. The other end of the metal feed line 4 is connected to the antenna control switch.

[0023] A directional radiating antenna, composed of a metal feed line and a ring-shaped metal strip, is a key component of testing equipment. When the transmitted signal and characteristic impedance are fed to two radially symmetrical points on the antenna, its radiation pattern approximates a heart shape. Eight directional radiating antennas, evenly distributed at 45° intervals, are controlled by an electronic switch activated by a feed command. This allows each antenna to radiate radio frequency (RF) signals from different azimuths. These signals are received by the directional antenna of an ultra-shortwave directional instrument positioned 15cm above the antenna, processed internally by the instrument, and the azimuth angle is displayed, completing the measurement task. This test antenna significantly reduces the testing distance. The azimuth selection switch controls the internal RF signal radiation, effectively reducing environmental and electromagnetic leakage. Its simple structure and portability allow for close-range testing, overcoming the limitations of field testing. Furthermore, a special resistor loading method achieves both high-performance antenna design and miniaturization requirements.

[0024] This invention achieves the output of radio frequency signals in eight azimuth angles by accessing different feeder signals. At the same time, a resistor access structure is designed to optimize the antenna band performance of the radiating antenna in the UHF band, with an in-band VSWR of <2.0.

Claims

1. A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument, characterized in that... The system includes a metal outer shell, a metal inner shell, an upper dielectric substrate, a lower dielectric substrate, a directional radiating antenna, a handle, and an antenna control switch. A circular opening is formed on the upper surface of the metal outer shell, within which a basin-shaped metal inner shell is housed. A step difference exists between the upper surfaces of the metal outer shell and the metal inner shell. The upper and lower dielectric substrates are positioned along the upper edge of the metal inner shell. Eight annular metal strips are evenly distributed along the outer edge of the dielectric substrates within the interlayer between the upper and lower dielectric substrates. A metal feed line is connected to the same side of each annular metal strip. The metal feed line passes through the gap between the two dielectric substrates and the metal inner shell, and connects to the antenna control switch located at the bottom of the metal inner shell along its outer surface. Each annular... A metal strip and its connected metal feed line form a directional radiating antenna. Eight directional radiating antennas provide radio frequency directional signals in eight directions: 0º, 45º, 90º, 135º, 180º, 225º, 270º, and 315º. A handle is provided on the side of the metal housing. Power cable passage holes and test instrument cable passage holes are provided on the bottom of both sides of the metal housing. The inner and outer surfaces of the metal housing are flat and smooth. A metal support column is set inside the metal housing. The inner housing is connected and fixed to the metal support column by screws. The metal housing is connected to the power supply and external test instruments through the power cable passage holes and test instrument cable passage holes to realize power supply and control.

2. A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument according to claim 1, characterized in that... The joint between the inner and outer metal shells is uniform and flat, and the inner and outer walls of the cavity are flat and smooth. The upper surface has screw holes for connection and fixation with the outer metal shell.

3. A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument according to claim 1, characterized in that... The upper and lower dielectric substrates are made of white FR-4 epoxy resin boards, and an annular metal strip is etched on the lower dielectric substrate.

4. A radiating antenna for detecting the directional function of an ultra-shortwave directional instrument according to claim 1, characterized in that... The metal feed line is a parallel double-conductor copper wire with a characteristic impedance of 50 ohms and an outer layer of insulating material. One end of the metal feed line is connected to the annular metal strip by solder through holes on the side of the metal inner shell and the gap of the dielectric substrate. The other end of the metal feed line is connected to the antenna control switch.

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