JP2016116124A - Distributed array antenna device and side lobe suppression method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress power in a side lobe direction while increasing power in a main lobe direction generated by in-phase synthesis.SOLUTION: A distributed array antenna device comprises: a plurality of antenna devices each including an orientation direction tracking mechanism and disposed in an array shape; and orientation direction error compensation means which controls a phase and an amplitude of a transmission signal that is transmitted from each of antennas, compensates for an orientation direction error after an orientation direction of each of the antenna is adjusted, and performs control in such a manner that the in-phase synthesis is performed on phases in a predetermined direction. In a path of a signal transmitted from at least one of the plurality of antenna devices, a structure is disposed which has such properties that a signal in a specific frequency band is permeated by a structure in which metals or dielectrics are periodically arrayed, and that a radiation phase of the permeated signal is made different in accordance with an incident angle of the signal. The orientation direction error is compensated by the orientation direction error compensation means, such that in-phase synthesis is performed in the main lobe direction and that power synthesis is performed with different phases in the side lobe direction.SELECTED DRAWING: Figure 1

Description

  The present invention suppresses sidelobe power in a distributed array antenna apparatus in which a plurality of antenna apparatuses are arranged in an array and the phase and amplitude of a transmission signal are controlled so as to be in-phase combined in a predetermined direction (receiving end). The present invention relates to a distributed array antenna apparatus and a sidelobe suppression method.

  In response to the broadbandization of satellite communication systems, it is necessary to increase the gain of antenna devices to be used. Although a high gain antenna device can be realized by increasing the size, an increase in installation location and cost due to the increase in size of the antenna device becomes a problem. As a method for solving this problem, a distributed array antenna apparatus has been proposed in which a plurality of antennas are arranged in an array and the phase and amplitude of a transmission signal are controlled so as to achieve in-phase synthesis at the receiving end (Patent Document 1). .

  In such a distributed array antenna device, a high gain of the antenna device can be realized by combining a plurality of existing small antennas without using a large antenna device. Furthermore, by combining a plurality of antenna devices, redundancy is ensured and fault tolerance is very high.

FIG. 4 shows a configuration example of a conventional distributed array antenna apparatus.
4, the distributed array antenna apparatus includes a plurality of antenna apparatuses 11-1 to 11-N, a modulator / demodulator 12 that processes transmission signals and reception signals, and a plurality of antenna apparatuses 11-1 to 11-N. And a signal synthesizer / distributor 13 that synthesizes the received signals of the plurality of antenna devices 11-1 to 11-N and outputs them to the modem 12, and a phase / amplitude setting unit that sets the phase and amplitude of the transmission signal 14-1 to 14-N, and error detection / phase amplitude for detecting the directivity direction error of each antenna and controlling each phase / amplitude setting unit so as to compensate for the directivity direction error and achieve in-phase synthesis at the receiving end. And a control unit 15.

  Note that means for detecting the directivity direction error of each antenna in the error detection / phase amplitude control unit 15 is omitted in the drawing. Specifically, the phase and amplitude are controlled so that in-phase synthesis is performed at the receiving end as follows. First, each antenna device has a directivity direction tracking mechanism, and mechanically tracks and captures a directivity direction corresponding to a desired receiving end. The error detection / phase amplitude control unit 15 changes the phase and amplitude of the transmission signal in a state where the directivity direction of each antenna device is directed to the receiving end, and corrects the path length and the phase difference from each antenna device to the receiving end. , While obtaining the amplitude and phase amount (error compensation amount) that maximizes the received signal (return signal) to be observed, and by controlling each phase / amplitude setting unit based on the error compensation amount, To achieve in-phase synthesis.

JP 2012-045596 A

Y. Kawakami, T. Hori, M. Fujimoto, R. Yamaguchi, and K. Cho, “Low-Profile Design of Metasurface Considering FSS Filtering Characteristics,” IEICE Trans. Commun., Vol.E95-B, no.2, pp.477-483, Feb. 2012. Y. Lee, X. Lu, Y. Hao, S. Yang, R. Ubic, JRG Evans, and CG Parini, “Rapid prototyping of ceramic millimeterwave metamaterials: simulations and experiments,” Microw. And Opt. Tech. Lett., vol.49, no.9, pp.2090-2093, Sept. 2007.

  In the conventional distributed array antenna apparatus shown in FIG. 4, it is possible to increase the power in the main lobe direction by controlling the phase and amplitude of the transmission signal so that in-phase combining is performed at the receiving end. However, since the power in the side lobe direction is also in-phase combined in the same manner as in the main lobe direction, the power equivalent to the power increase amount in the main lobe also increases in the side lobe direction. When another antenna device using the same frequency band exists in the increased side lobe direction, the interference given to the antenna device increases due to an increase in power in the side lobe direction.

  An object of the present invention is to provide a distributed array antenna apparatus and a side lobe suppression method capable of suppressing the power in the side lobe direction while increasing the power in the main lobe direction by in-phase synthesis.

  The first invention includes a directivity direction tracking mechanism that adjusts the directivity direction of an antenna to a predetermined direction, and controls a plurality of antenna devices arranged in an array and the phase and amplitude of a transmission signal transmitted from each antenna. In a distributed array antenna apparatus comprising a directivity direction error compensation means that compensates a directivity direction error after adjusting a directivity direction of each antenna and controls a phase in a predetermined direction to be in-phase combined, a plurality of antenna devices A characteristic in which a signal of a specific frequency band is transmitted through a path of a signal transmitted from at least one antenna device in a structure in which metals or dielectrics are periodically arranged, and the radiation phase of the transmitted signal varies depending on the incident angle of the signal The main lobe direction is in-phase combined by compensating the pointing direction error by the pointing direction error compensation means, and the side lobe method It is configured to perform power combining in different phases.

  In the distributed array antenna device of the first invention, the structure is arranged in the vicinity of the opening surface of the primary radiator of the antenna device, in the vicinity of the reflecting surface or opening surface of the antenna reflector, or in the radome that covers the antenna device. .

  The second invention includes a directivity direction tracking mechanism that adjusts the directivity direction of the antenna to a predetermined direction, and controls a plurality of antenna devices arranged in an array and the phase and amplitude of a transmission signal transmitted from each antenna. In the sidelobe suppression method of the distributed array antenna apparatus comprising the directivity direction error compensation means for compensating the directivity direction error after adjustment of the directivity direction of each antenna and controlling the phase of the predetermined direction to be in-phase synthesis, A signal in a specific frequency band is transmitted through a path of a signal transmitted from at least one antenna device of a plurality of antenna devices in a structure in which metals or dielectrics are periodically arranged, and the transmitted signal is transmitted according to the incident angle of the signal. Structures with different radiation phases are arranged, and the main lobe direction is in-phase combined by compensating the pointing direction error by the pointing direction error compensation means. And side lobe direction performs power combining in different phases.

  The present invention compensates the directivity direction error so that in-phase synthesis is performed in a predetermined direction (reception end) in a state where at least one of signals transmitted from a plurality of antenna devices passes through the structure, and thereby the main lobe direction However, the side lobe directions are combined with each other according to the function of the structure, so that the side lobes can be suppressed. Therefore, the interference given to the antenna device in the side lobe direction can be reduced.

It is a figure which shows the Example structure of the distributed array antenna apparatus of this invention. It is a figure which shows the structural example of the structure 23, and a radiation phase characteristic. It is a figure which shows the radiation pattern by the distributed array antenna apparatus of this invention. It is a figure which shows the structural example of the conventional distributed array antenna apparatus.

FIG. 1 shows an embodiment of a distributed array antenna apparatus according to the present invention.
In FIG. 1, a plurality of antenna devices 11-1 to 11-N, a modulator / demodulator 12, a signal synthesizer / distributor 13, a phase / amplitude setting unit 14-1 to 14-N, and an error detection / phase amplitude control unit 15 are The configuration is the same as that of the conventional distributed array antenna apparatus shown in FIG. 4, and the same processing is performed for each.

  A feature of the distributed array antenna apparatus of the present invention is that a structure 23 in which metals or dielectrics are periodically arranged is arranged in a path of a signal transmitted from at least one of the antenna apparatuses 11-1 to 11-N. By the way. The structure 23 has a characteristic that a signal in a specific frequency band is transmitted and the radiation phase of the transmitted signal is different depending on the incident angle of the signal.

As a specific arrangement position of the structure 23, any of the following may be used.
(1) Near the opening surface of the primary radiator 21 of at least one antenna device.
(2) Near the reflection surface of the antenna reflector 22 of at least one antenna device.
(3) Near the opening surface of the antenna reflector 22 of at least one antenna device (between the primary radiator 21 and the antenna reflector 22 and including the back surface of the primary radiator 21).
(4) A radome formed on the surface of the radome or the structure 23 covering the entire at least one antenna device.
In the case where the antenna device has a structure using a plurality of antenna reflectors 22, it may be intermediate between the plurality of antenna reflectors 22.

FIG. 2 shows a structural example of the structure 23 and a radiation phase characteristic.
The structure 23 has a structure such as a frequency selection plate (Non-patent Document 1) in which a plurality of elements (slots and patches) as shown in FIG. Woodpile-type metamaterials (Non-patent Document 2) and the like. Note that one side of the loop-type slot is about ¼ of the wavelength of the transmitted frequency band.

  FIG. 2 (2) shows the relationship of the radiation phase difference with respect to the incident angle when electromagnetic waves are incident on the structure 23 shown in FIG. 2 (1) from the vertical direction of the drawing. It can be seen that the radiation phase difference changes greatly as the incident angle increases.

  In a state where such a structure 23 is arranged in either the radiation direction of the primary radiator 21 or the reflection direction of the antenna reflector 22 of the antenna devices 11-1 to 11-N, the error detection / phase amplitude control unit 15 Implement control.

  First, each antenna device mechanically tracks and captures a directivity direction corresponding to a desired receiving end by a directivity direction tracking mechanism. The error detection / phase amplitude control unit 15 changes the phase and amplitude of the transmission signal in a state where the directivity direction of each antenna device is directed to the receiving end, and corrects the path length and the phase difference from each antenna device to the receiving end. , While obtaining the amplitude and phase amount (error compensation amount) that maximizes the received signal (return signal) to be observed, and by controlling each phase / amplitude setting unit based on the error compensation amount, To achieve in-phase synthesis.

  Here, the error detection / phase amplitude control unit 15 controls the phase in a predetermined direction to be in-phase synthesis in a state where the transmission signal passes through the structure 23. At this time, the phase other than the predetermined direction Since the phase rotation amount for each antenna device is different depending on the function 23, in-phase synthesis is not performed during synthesis. That is, while the phases in the main lobe direction are combined in phase, the side lobes are combined in power in different phases, so that side lobes are suppressed.

FIG. 3 shows a radiation pattern by the distributed array antenna apparatus of the present invention.
Here, two antenna devices are used. A broken line is the characteristic by the conventional method which does not use the structure 23. FIG. A solid line is a characteristic according to the proposed method of the present invention using the structure 23. The main lobe has no difference between the conventional method and the proposed method due to the effect of in-phase synthesis, but the side lobe has been confirmed to be improved by 2 dB by the proposed method.

11-1 to 11-N antenna apparatus 12 modem / demodulator 13 signal synthesizer / distributor 14-1 to 14-N phase / amplitude setting unit 15 error detection / phase amplitude control unit 21 primary radiator 22 antenna reflector 23 structure

Claims (3)

A plurality of antenna devices arranged in an array, each including a directivity direction tracking mechanism for adjusting the directivity direction of the antenna to a predetermined direction;
A directivity direction error that controls the phase and amplitude of a transmission signal transmitted from each antenna, compensates for the directivity error after adjustment of the directivity direction of each antenna, and controls the phase in the predetermined direction to be in-phase combined. In a distributed array antenna device comprising compensation means,
A signal of a specific frequency band is transmitted through a path of a signal transmitted from at least one antenna device of the plurality of antenna devices with a structure in which metals or dielectrics are periodically arranged, and a signal after transmission depending on an incident angle of the signal Structure having different characteristics of radiation phases of the main lobe direction by in-phase synthesis and side lobe direction by power synthesis by compensation of the directivity direction error by the directivity direction error compensation means A distributed array antenna device, characterized in that The distributed array antenna apparatus according to claim 1,
The structure is disposed in the vicinity of the opening surface of the primary radiator of the antenna device, or in the vicinity of the reflection surface or opening surface of the antenna reflector, or in a radome that covers the antenna device. apparatus. A plurality of antenna devices arranged in an array, each including a directivity direction tracking mechanism for adjusting the directivity direction of the antenna to a predetermined direction;
A directivity direction error that controls the phase and amplitude of a transmission signal transmitted from each antenna, compensates for the directivity error after adjustment of the directivity direction of each antenna, and controls the phase in the predetermined direction to be in-phase combined. In a sidelobe suppression method for a distributed array antenna device comprising compensation means,
A signal of a specific frequency band is transmitted through a path of a signal transmitted from at least one antenna device of the plurality of antenna devices with a structure in which metals or dielectrics are periodically arranged, and a signal after transmission depending on an incident angle of the signal Arrange structures with different radiation phases,
A side lobe suppression method, wherein the main lobe direction is in-phase combined and the side lobe direction is different in phase by compensation of the pointing direction error by the pointing direction error compensating means.

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