KR101559933B1 - Aircraft Compatibility Evaluating Method of an Antenna - Google Patents

Abstract

The present invention relates to a method for evaluating installation compatibility of an antenna with an aircraft. The method for evaluating installation compatibility of an antenna with an aircraft comprises: (a) a step of considering an operating frequency of the antenna to determine a diameter of a ground of the antenna; (b) a step of evaluating matching performance of the antenna; (c) a step of considering a flying condition of the aircraft on which the antenna is to be installed to determine a main communication domain; and (d) a step of considering the flying condition and the main communication domain to evaluate gain performance of the antenna. Accordingly, the performance of the antenna required during a real flight can be systematically and accurately evaluated in steps.

Description

[0001] The present invention relates to an Aircraft Compatibility Evaluation Method of an Antenna,

The present invention relates to a method of evaluating the suitability of an antenna for mounting on an aircraft, and more particularly, to an evaluation process capable of accurately and systematically evaluating the performance of an antenna mounted on an aircraft.

Recently, in consideration of aerodynamic characteristics and durability, many communication antennas in the form of a blade have been introduced and used. However, when the blade antenna is mounted on an aircraft, performance degradation such as gain reduction or pattern distortion may be seen due to diffraction and reflection from the structure of the aircraft. In particular, when the aircraft is operated, .

Antenna performance evaluation should be done to solve these problems. For example, when determining the antenna ground, use the infinite ground or use the self-ground of the antenna separately, or observe the change in matching performance and radiation pattern when mounting the aircraft, The suitability of the blade antenna for mounting the aircraft is being evaluated.

From this antenna performance evaluation, problems caused by the blade antenna mounted on the aircraft can be reduced.

Japanese Patent Application Laid-Open No. 1999-068640 (Jan.

However, the blade antenna evaluation method has difficulty in measuring the antenna performance by using the infinite ground when determining the antenna ground or using the own ground of the antenna. Moreover, not only is the blade antenna evaluation method not systematic, but it is impossible to accurately determine the performance of the antenna by merely arranging the antenna as far as possible to the peripheral antenna and the protruding structure, or evaluating the matching performance and the radiation gain of the antenna.

In this way, evaluating only the specific performance of the antenna and evaluating the suitability of the aircraft for installation can not predict the performance change and problems of the antenna during actual operation. In particular, The interference evaluation method can not necessarily reflect the conditions necessary for actual equipment operation.

Therefore, there is a demand for a performance evaluation process that can more accurately and systematically evaluate the performance of an aircraft-mounted antenna.

In view of the above, the present invention aims to provide a systematic and comprehensive evaluation process for evaluating aircraft mounting performance of an antenna in consideration of aircraft operating conditions, thereby achieving a systematic and comprehensive evaluation process .

In addition, the present invention, taking the above points into consideration, determines the main communication area in consideration of the flight conditions of the airplane, and determines the performance required for the airborne antenna such as the minimum gain required for the operation of the airplane, A method of evaluating the fit of an antenna to an aircraft that provides an accurate and systematic evaluation process.

Further, when evaluating the degree of interference of a plurality of antennas mounted on an aircraft, the present invention evaluates the received power of the receiving antenna reflecting the input power and the coupling coefficient between the antennas according to the frequency of the transmitting antenna with the minimum receiving sensitivity of the equipment The purpose of this study is to evaluate the feasibility of mounting an antenna on an aircraft.

According to another aspect of the present invention, there is provided a method of evaluating an aircraft mounting fitness of an antenna, the method comprising the steps of: (a) determining a diameter of a ground of the antenna in consideration of an operating frequency of the antenna; (b) evaluating a matching performance of the antenna; (c) determining a main communication area of the antenna in consideration of a flight condition of the aircraft on which the antenna is to be mounted; (d) evaluating the gain performance of the antenna in consideration of the navigation condition and the main communication area.

In addition, the method of evaluating the onboard suitability of the antenna may further include: (e) determining the aircraft mount position of the antenna; And (f) evaluating the mounting performance of the antenna at the mounting position.

In addition, the method of evaluating the onboard suitability of the antenna may further include (g) evaluating a coupling performance between the antennas mounted on the aircraft.

In addition, the step (c) may include the step of evaluating the antenna by adjusting the main communication area according to the mounting position of the antenna and the radiation direction of the antenna.

Meanwhile, the step (d) may evaluate an average copy gain of the antenna in the main communication area.

In the step (d), deriving a required minimum radiant gain for each operating frequency band so as to prevent a communication link with the base station on the ground from being broken in the operating frequency band of the antenna, .

Further, the step (g) may include a step of comparing the input power of the transmitting antenna with a value including the coupling coefficient between the antennas and the minimum perceptual power of the receiving antenna to evaluate the inter-antenna interference level.

In addition, the airline operating conditions may include the operating course, altitude, and turning angle information of the aircraft.

According to the evaluation method of the aircraft mounting suitability of the blade antenna according to the present invention, the performance of the blade antenna required in actual aircraft operation is evaluated systematically, accurately, and step by step by considering the flight conditions of the aircraft.

In addition, in the method of evaluating the fitting performance of an aircraft with a blade antenna according to the present invention, performance evaluation of the antenna alone and mounting performance according to the installation position of the aircraft are evaluated step by step, so that not only performance verification as an antenna single unit, There are exactly predictable effects.

In addition, in the evaluation method of the aircraft mounted suitability of the blade antenna according to the present invention, the minimum radiant gain of the antenna is considered in consideration of the antenna transmission model, so that the actual evaluation criteria in the actual aircraft operating area can be provided, A substantial quantitative evaluation standard can be provided.

In addition, according to the evaluation method of the aircraft mounted fitness of the blade antenna according to the present invention, it is possible to evaluate the degree of inter-equipment interference more accurately by reflecting the necessary conditions for operation of the actual equipment in the evaluation of interference between the aircraft mounted antennas.

FIG. 1 is a flow chart for evaluating the performance of a single piece of a blade antenna in a method of evaluating the suitability of an antenna according to the present invention, FIG. 2 is an example of determining an antenna ground in a method of evaluating the suitability of an aircraft for a blade antenna according to the present invention FIG. 3 is a side view of a single blade antenna designed for the method of evaluating aircraft mounting fitness according to the present invention, FIG. 4 is an individual reflection coefficient of an antenna capable of evaluating carrier matching performance of the designed blade antenna of FIG. 3, FIG. 6 is a main communication area of an aircraft in which the operating scenario of FIG. 5 is considered, and FIG. 7 is an example of a main communication area of the aircraft in FIG. In the invention, it is assumed that the aircraft is operating at a speed of -100 dB m is an example of a reception antenna minimum gain curve for maintaining the reception power of m or more, Fig. 8 is an example of a 3D radiation pattern appearing at 500 MHz of the designed blade antenna of Fig. 4, and Fig. FIG. 10 is a flowchart showing the first to fifth blade antennas mounted on an aircraft according to the present invention, FIG. 11 is a view showing a state where the first to fifth blades And the first blade antenna of the antenna is an antenna radiation pattern at 500 MHz.

Embodiments of the present invention will now be described in detail with reference to the accompanying exemplary drawings.

FIGS. 1 and 9 illustrate a method for evaluating the suitability of an aircraft for mounting a blade antenna according to the present invention. From this, And loading performance evaluation (Figs. 9 to 11).

Hereinafter, a method for evaluating the performance of a single component of the antenna, which is performed through steps S10 to S17 of FIG. 1, will be described with reference to FIGS. 2 to 8. FIG.

The individual antenna design is performed first as in S10. This antenna design is accomplished through a blade antenna design and modeling program. Then, as in S11, the ground of the individual antenna is determined on the individual antenna designed in consideration of the operating frequency band.

Fig. 2 shows an example of the designed antenna 10 and the ground 11, which shows a circular ground 11 having a circular shape with a diameter of 1.2 m considering the operating frequency of the designed antenna 10. In this case, by considering the operating frequency of the antenna 10 and determining the ground 11, it is possible to accurately evaluate the performance of the designed antenna 10 separately. Therefore, in the antenna 10 having the circular ground 11, it is possible to solve the difficulty of measuring the antenna performance of the antenna evaluation method in which the antenna ground is determined by using the infinite ground or using the self ground of the single antenna have. FIG. 3 shows an example in which the antenna 10 of FIG. 2 and the feeder 10a having a circular ground 11 of 1.2 meters in diameter are disposed downwardly and composed of a single piece.

Then, the single-piece matching performance is evaluated for the antenna 10 and the ground 11 determined as S12. 4 is a reflection coefficient diagram of an individual antenna applied to the single piece product matching performance evaluation of the antenna 10, the ground 11, and the feed part 10a. As a result of the matching performance analysis, the VHF-UHF band 100 It is confirmed that it can be used as an aircraft blade antenna at about -5 dB or less at MHz ~ 500 MHz.

On the other hand, if the result of the matching performance evaluation in step S13 does not satisfy the criterion, the performance of the antenna 10 is tuned or optimized by adjusting to the standard by entering S14.

On the other hand, if the matching performance is satisfied from the result of the matching performance evaluation of the individual products made in S13, the main communication area is determined in consideration of the operating condition of the aircraft 1 on which the antenna 10 is mounted by entering S15. In this case, the antenna 10 in the main communication area, which includes information on the navigation course (distance, position, direction, etc.), altitude, turning angle, Of the aircraft. Therefore, the performance and the problems of the antenna 10 occurring during actual flight operation, which is impossible in the conventional method of evaluating the fitting fitness of the antenna 10 by observing only the matching performance and the radiation pattern change when the aircraft 1 is mounted, The invention can be more accurately predicted.

Fig. 5 shows an example of a navigation scenario for determining the main communication area of the antenna 10. Fig. As shown in the figure, the aircraft 1 starts communication with the base station at a distance D = 20 km after takeoff, and the altitude H of the aircraft ₁ is assumed to be about h ₁ . It is assumed that the maximum operating range of the aircraft (1) is within about 200 km, the turn is about 15 ° at the return point, and then returns to the base station.

6 shows an example in which the main communication area is determined to be -45 DEG to -15 DEG since the minimum elevation angle [ theta] _{EL, L} is -45 DEG and the maximum elevation angle [ theta] _{EL, H} is 15 DEG. The reason for this is that the aircraft 1 having a navigation scenario considering the navigation course, altitude, turning angle, etc. starts communication at a distance of 20 km and the line of sight of the aircraft 1 and the base station at a distance of 20 km Consideration is given to having an altitude angle of 30 °, reflecting the turning angle 15 ° of the aircraft (1). The minimum elevation angle? _{EL, L of the} communication line of sight is determined as ? _{EL, L} = - (30 + 15)? = -45 占 and at the turning point of 200 km, the line of sight between the aircraft 1 and the base station Since the angle approaches 0 DEG, the maximum elevation angle [ theta] _{EL, H} can be determined to be 15 DEG.

Next, the gain performance of the antenna 10 is evaluated in the main communication area determined as S16. In this case, the actual aerial scenario for evaluating the radiative gain performance of the antenna 10 at the time of loading the aircraft is used to set the antenna 10 minimum radiative gain which can maintain the communication link with the ground. Therefore, a more quantitative evaluation can be made by reflecting the actual evaluation criteria in the real aircraft operating area, which was impossible in the conventional method of determining the minimum radiation gain of the antenna 10 without considering the radio wave transmission model and applying it to the evaluation of the antenna 10 It can be possible.

On the other hand, the minimum radiation gain is determined by the following equation (1).

&Quot; (1) "

According to Equation (1) above, the required minimum radiation gain of the aircraft-mounted antenna 10 is the minimum radiation gain curve indicated by the dotted line in Fig. The minimum radiation gain curve of FIG. 7 shows that the antenna 10 of the base station on the ground is mounted at a height of 20 m from the ground, and the effective isotropic radiated power (EIRP) is 46 dBm. ) Can maintain a received power of -100 dBm or more from the base station up to 200 km, the maximum operating area.

From this, the evaluation criterion of the aircraft blade antenna can be defined as the minimum radiation gain curve (solid line) with a margin of + 10dB in the minimum radiation gain curve (dotted line). The reason for this is that the performance of the antenna changes depending on manufacturing errors, temperature, and humidity that can occur in the manufacturing process of the antenna, which is compensated for by a margin of 10 dB. Therefore, in the main communication area (Fig. 6) determined from -45 DEG to 15 DEG, the average gain satisfies _{Gmin.VHF, Gmin.UHF} (minimum radiation gain) as evaluation criterion of the minimum radiation gain curve (solid line) It can be evaluated that stable transmission and reception with the base station on the ground is possible.

Then, the antenna gain performance evaluation result is checked as in S17. 8 shows the antenna 3D radiation pattern of the blade antenna (FIG. 3) at 500 MHz, and the average gain, the maximum gain, the minimum gain, and the deviation of such antenna radiation pattern are specified in Table 1 below.

Max. gain (dBi) Min. gain (dBi) Avg. gain (dBi) Dev. (DBi) 3D-pattern
(simu.) -0.51 -42.64 -11.81 42.13

From Table 1, it can be seen that the blade antenna has an average gain of about -11.81 dBi or more in the main communication area, which is about 3.3 dB higher than the minimum radiation gain (G _{min . UHF} ) in the UHF band.

As a result of the check in step S17, the antenna performance is tuned or optimized as in step S14 when the evaluation reference is not satisfied, and then fed back to step S10 to perform the performance evaluation of the single component again (S11 to S17).

Here, when the main communication area is determined, the main communication area may be adjusted according to the mounting position and radiation direction of the antenna 10 to perform evaluation several times. For example, when there are a plurality of expected operating scenarios, it is possible to set a plurality of main communication areas according to a plurality of operating scenarios and evaluate whether the performance characteristics required for the antenna 10 in each of the plurality of main communication areas are satisfied .

On the other hand, as a result of the check in S17, the performance evaluation of the antenna alone, which is one embodiment of the method of evaluating the onboard suitability at the time of passing the evaluation standard, is completed.

Then, an aircraft loading performance evaluation is performed in an embodiment of the aircraft mounted fitness evaluation method of the present invention.

Hereinafter, an aircraft loading performance evaluation method performed through steps S20 to S24 of FIG. 9 will be described with reference to FIGS. 10 and 11. FIG.

As shown in S20, the positions of the individual blade antennas on the aircraft are determined. FIG. 10 shows respective positions where a plurality of blade antennas composed of the first to fifth antennas Ant1 to Ant5 are mounted on the aircraft 1. In FIG.

Then, the antenna performance at the mounting position is evaluated as in S21. FIG. 11 shows antenna radiation patterns of the first antenna Ant1 at 500 MHz, and antenna performance evaluation is performed for a plurality of blade antennas by applying Equation (2) under these conditions.

&Quot; (2) "

 The results of Table 2 are obtained from the antenna gain calculation formula of the above-mentioned equation (2).

Max. gain (dBi) Min. gain (dBi) Avg. gain (dBi) Dev. (dBi) 3D-pattern
(simu.) 1.86 -50.63 -11.32 52.49

Referring to Table 2, it can be seen that the gain in the lower end direction is higher than the gain in the upper direction due to the influence of the aircraft structure. At 500 MHz in the UHF band, the gain performance is higher than the minimum radiation gain (Gmin.UHF) by more than -11.32 dBi, which is more than 2.8 dB higher than the average radiation gain.

Then, the result of the antenna performance evaluation is checked as in S22, and if the result is not passed, the feedback is made to S20 so that the mounting position of the blade antenna with respect to the aircraft 1 is readjusted. On the other hand, when the antenna performance evaluation is passed, the coupling performance between the first antenna Ant1 that has passed the performance and the second antenna Ant2 adjacent thereto is evaluated by going into S23. When evaluating the degree of interference of a plurality of blade antennas composed of the first to fifth antennas (Ant1 to Ant5) mounted on the airplane 1 in the evaluation of the coupling performance, the input power according to the frequency of the transmitting antenna and the coupling The interference power between the antennas is evaluated by comparing the reception power of the reception antenna reflecting the ring coefficient to the minimum reception sensitivity of the equipment. Therefore, by evaluating only the coupling coefficient between antennas for evaluating the interference between the antennas on the aircraft, the necessary conditions for the operation of the actual equipment, which was not reflected in the existing evaluation method for evaluating interference between the mounting devices, are reflected, Can be evaluated.

The following equation (3) is used to calculate inter-device interference in the coupling performance calculation.

&Quot; (3) "

The coupling performance between the first antenna Ant1 and the second antenna Ant2 is calculated using the power P _in applied to the transmitting antenna and the coupling coefficient S ₂₁ between the transmitting and receiving antennas, do. The results are shown in Table 3, which shows the calculated values for inter-device interference.

Classification Ant.1 (transmission) Coupling between antennas Ant.2 Receive power


@ 400MHz Lowest reception sensitivity Interference Transmit signal strength (@ 400MHz) -72dBm -68.6dB -140.6dBm -103dBm No interference Remarks 57.3dBm
@ 1030MHz -72 dBm + (-68.6 dB) = -140.6 dBm

Table 3 shows the case where the first antenna Ant1 operates at 1030 MHz, has a transmission power of 57.3 dBm at 1030 MHz, and has a spurious wave of -72 dBm at an operating frequency of 400 MHz. In this case, the coupling between the first antenna Ant1 and the second antenna Ant2 becomes 68.6 dB, and at 400 MHz, the second antenna Ant2 has a reception power of -140.6 dBm. Therefore, since the second antenna Ant2 is lower than the minimum reception power of -103 dBm, it can be seen that no interference occurs between the on-board devices.

<Table 4>

In Table 4, if the power applied to the receiving antenna is equal to or higher than the minimum power receiving level, the separation distance is adjusted and reassessed. If it is lower than the minimum power receiving level, On the other hand, in Table 4, the bold portion indicates that the interference between the antennas 10 is not satisfied because the received power is higher than the minimum received power of -105 dBm at 400 MHz.

If the coupling performance between the first antenna Ant1 and the second antenna Ant2 does not satisfy the criterion, the feedback is fed back to the step S20. As a result, After the mounting position of the antenna is readjusted, the performance is evaluated again in S21 to S23. On the other hand, if the coupling performance between the first antenna Ant1 and the second antenna Ant2 satisfies the criterion, it is terminated.

As described above, in the evaluation method of the aircraft mounting fitness of the antenna 10 according to the present invention, unlike the conventional method in which only the specific performance of the antenna 10 is evaluated to evaluate the fitting performance of the aircraft, all the considerations A systematic and comprehensive evaluation process can be built up in stages.

Particularly, the method of evaluating the onboard suitability of the antenna 10 according to the present invention may be implemented by a software algorithm consisting of a series of control codes, or a storage medium on which a software algorithm is recorded.

In addition, the user can input the parameters of each antenna 10 and verify the singularity performance and the mount performance of the antenna 10 according to the sequence of the above-described aircraft mounting fitness evaluation method.

Although a few embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention. There will be. The scope of the invention will be determined by the appended claims and their equivalents.

1: Aircraft 10: Antenna
10a: power supply portion 11: ground

Claims (8)

A method for evaluating an aircraft mounting fitness of an antenna,
(a) determining a diameter of a ground of the antenna in consideration of an operating frequency of the antenna;
(b) evaluating a matching performance of the antenna;
(c) determining a main communication area of the antenna in consideration of a flight condition of the aircraft on which the antenna is to be mounted;
(d) evaluating the gain performance of the antenna in consideration of the navigation condition and the main communication area;
Wherein the method comprises the steps of:
The method according to claim 1,
(E) determining the aircraft mounting position of the antenna; And (f) evaluating the mounting performance of the antenna at the mounting position;
Further comprising the step of evaluating the suitability of an antenna for mounting on an aircraft.
3. The method of claim 2,
(G) evaluating a coupling performance of each of the antennas mounted on the aircraft when the plurality of antennas are mounted on the aircraft;
Further comprising the step of evaluating the suitability of an antenna for mounting on an aircraft.
The method of claim 3,
(G) comparing the input power of the transmitting antenna with the minimum perceptual power of the receiving antenna, the value including the coupling coefficient for each of the antennas, and evaluating the degree of interference for each of the antennas;
Wherein the method comprises the steps of:
4. The method according to any one of claims 1 to 3,
Wherein the step (c) includes the step of evaluating the antenna by adjusting the main communication area according to the mounting position of the antenna and the radiation direction of the antenna.
4. The method according to any one of claims 1 to 3,
Wherein the step (d) evaluates an average radiated gain of the antenna in the main communication area.
The method according to claim 6,
Wherein the step (d) includes deriving a required minimum RF gain for each operating frequency band so as to prevent a communication link with the base station on the ground from being broken in an operating frequency band of the antenna, The method comprising the steps of:
4. The method according to any one of claims 1 to 3,
Wherein the operating condition includes a flight course, altitude, and turning angle information of the aircraft.

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