JP2008048007A - Array antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an array antenna system which is less in power consumption and computational complexity than a conventional technique. <P>SOLUTION: In the array antenna system, a controller 7 turns off a switch 3a and also turns off a control signal to be applied to a phase shifter 2a to judge whether or not a reception signal arrives from the reception power level of a radio signal received by an antenna element 1a. When judging that the reception signal arrives, the controller 7 turns on the switch 3a and outputs the control signal to the phase shifter 2a to control the phase shifter 2a to direct a main beam of an array antenna comprising antenna elements 1a and 1b in the direction of the arriving reception signal based upon the radio signal of the array antenna. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an array antenna device used in a radio communication system of a microwave band, a quasi-millimeter wave band, or a millimeter wave band.

  Conventionally, an array antenna apparatus (hereinafter, referred to as a plurality of DC voltage control type phase shifters) that includes a plurality of antenna elements and a plurality of DC voltage control type phase shifters for shifting a radio signal received by each antenna element by a predetermined phase shift amount. In an array antenna device according to the prior art), the direction of a received signal that arrives based on the directivity and the received signal level of the array antenna device is estimated by a MUSIC (Multiple Signal Classification) method or the like, and each phase shifter is An algorithm for controlling the amount of phase shift so as to be directed to the direction of the received signal from which the main beam of the array antenna apparatus arrives is used. By configuring the array antenna device in this way, the thermal noise component received together with the desired wave signal, the same channel interference wave of the same frequency from the adjacent base station, and the desired wave arrived via a large path Therefore, it is possible to suppress a delayed wave that causes a delay in time and to receive a desired wave signal with high gain.

JP 2000-101328 A. JP 2000-196328 A.

  However, the array antenna device according to the prior art has a problem that power consumption is large because a control voltage is always applied to each phase shifter regardless of whether or not a received signal has arrived. In addition, since the direction of arrival estimation processing by the MUSIC method or the like has a large amount of computation, when the array antenna device according to the related art is mounted on a wireless device using a computing device with a low computation speed, the load on the wireless device is large. There was a problem.

  An object of the present invention is to solve the above-described problems and provide an array antenna apparatus that consumes less power and has a smaller amount of calculation than the prior art.

The array antenna apparatus according to the present invention is
In an array antenna device in which at least one first antenna element and at least one second antenna element are juxtaposed in a predetermined arrangement shape,
At least one switch means connected between the first antenna element and the second antenna element;
A phase shifter that shifts a radio signal received by the second antenna element by a predetermined phase shift amount based on an applied control signal;
When the switch means is on, the first received power level of the radio signal received by the first antenna element is detected, and a first detection signal indicating the first received power level is generated and output. When the switch means is off, the radio signal received by the first antenna element and the radio signal output from the phase shifter are combined, and the second radio signal of the combined array antenna is synthesized. Detecting means for detecting a received power level of the second and generating and outputting a second detection signal indicating the second received power level;
The switch means is turned off and the control signal applied to the phase shifter is turned off. Based on the first detection signal, it is determined whether a received signal has arrived, and it is determined that the received signal has arrived. Then, the switch means is turned on and a control signal is output to the phase shifter, and the phase shift is performed so that the main beam of the array antenna is directed to the direction of the received signal based on the radio signal of the array antenna. And a control means for controlling the device.

In the array antenna device,
A plurality of second antenna elements;
A plurality of phase shifters inserted between feed points of the second antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna The phase shifters are controlled so as to be suitable for the above.

In the array antenna device,
A plurality of first antenna elements;
A plurality of phase shifters inserted between the feed points of the first antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna The phase shifters are controlled so as to be suitable for the above.

Furthermore, in the array antenna device,
A plurality of first antenna elements;
A plurality of second antenna elements;
A plurality of phase shifters inserted between the feed points of the first antenna elements adjacent to each other;
A plurality of phase shifters inserted between feed points of the second antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna The phase shifters are controlled so as to be suitable for the above.

In the array antenna device,
When the control means determines that the received signal has arrived, it turns on the switch means and outputs a control signal to each phase shifter, so that the second received power level of the radio signal of the array antenna is substantially equal. Each of the phase shifters is controlled so as to be a maximum value and to be directed to the direction of the received signal from which the main beam of the array antenna arrives.

Furthermore, in the array antenna device,
When it is determined that the received signal has arrived, the control means turns on the switch means and outputs a control signal to each phase shifter, and the carrier-to-noise and interference wave power ratio of the radio signal of the array antenna Each phase shifter is controlled so that becomes substantially the maximum value and faces the direction of the received signal from which the main beam of the array antenna arrives.

Furthermore, in the array antenna device,
Each of the first antenna elements and each of the second antenna elements are juxtaposed at half-wave intervals of the radio signal.

  According to the array antenna apparatus of the present invention, the detection means detects the first reception power level of the radio signal received by the first antenna element when the switch means is on, and detects the first reception power. A first detection signal indicating a level is generated and output, and when the switch means is off, the wireless signal received by the first antenna element and the wireless signal output from the phase shifter are combined and combined Detecting the second received power level of the radio signal of the array antenna generated and generating and outputting a second detection signal indicating the second received power level, the control means turns off the switch means and The control signal applied to the phase shifter is turned off, and it is determined whether or not a received signal has arrived based on the first detection signal. When it is determined that the received signal has arrived, the switch means is turned on and shifted. Output control signal to phase shifter , Controls the phase shifter to face the direction of the reception signal main beam of the array antenna arrives based on the radio signal of the array antenna. Therefore, the power consumption is small and the calculation amount is small as compared with the prior art.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same component.

First embodiment.
FIG. 1 is a block diagram showing a configuration of the array antenna apparatus according to the first embodiment, and FIG. 2 is a flowchart showing a radio signal reception process executed by the controller 7 of FIG. 1, the array antenna apparatus according to the first embodiment includes antenna elements 1a and 1b, a phase shifter 2a, a switch 3a, a combiner 81, a directional coupler 4, and a power detection circuit 5. The wireless reception circuit 6, the controller 7 including the reception power memory 7 m, and the output terminal 8 are configured.

  In FIG. 1, the array antenna apparatus according to this embodiment includes a switch 3a connected between an antenna element 1a and an antenna element 1b, and a radio signal received by the antenna element 1b based on an applied control signal. When the switch 3a is on, the first received power level of the radio signal received by the antenna element 1a is detected to detect the first received power level. Is generated and output, and when the switch 3a is OFF, the radio signal received by the antenna element 1a and the radio signal output from the phase shifter 2a are synthesized and synthesized. The power detection circuit 5 that detects the second reception power level of the radio signal of the array antenna and generates and outputs the second detection signal indicating the second reception power level, and the switch 3a are turned off. The control signal applied to the phase shifter 2a is turned off, it is determined whether or not a received signal has arrived based on the first detection signal, and when it is determined that the received signal has arrived, the switch 3a is turned on and A controller 7 that outputs a control signal to the phase shifter 2a and controls the phase shifter 2a so that the main beam of the array antenna is directed in the direction of the received signal that arrives based on the radio signal of the array antenna. Features.

  In FIG. 1, antenna elements 1a and 1b are patch antennas having the same directivity characteristics, and are juxtaposed at intervals of half wavelengths of radio signals received by the array antenna apparatus of FIG. The phase shifter 2a is a direct current voltage control type phase shifter. When a control voltage V, which is a control signal, is applied from the controller 7, a radio signal received by the antenna element 1b is converted into a predetermined phase shift amount. The phase is shifted by δ and output. A synthesizer 81, which is an adder, synthesizes a radio signal received by the antenna element 1a and a radio signal input from the phase shifter 2a via the switch 3a, and the power detection circuit via the directional coupler 4. 5 and the radio reception circuit 6. The power detection circuit 5 detects the received power level of the input radio signal and outputs a detection signal indicating the detected received power level to the controller 7. The radio reception circuit 6 includes a high-frequency circuit such as a high-frequency filter that separates frequencies, a high-frequency amplifier that amplifies the radio signal, and a mixer that converts the radio signal into an intermediate-frequency signal having a predetermined intermediate frequency. An intermediate frequency circuit such as an intermediate frequency filter, a demodulation circuit that demodulates the intermediate frequency signal into a baseband signal, and a signal processing circuit that extracts data from the baseband signal. In response to the data reception start signal from the controller 7, the wireless reception circuit 6 performs predetermined high frequency filter processing and high frequency amplification processing on the input wireless signal, and the processed wireless signal is processed at a predetermined intermediate frequency. After the low frequency conversion to the intermediate frequency signal, intermediate frequency filter processing is performed on the intermediate frequency signal, the intermediate frequency signal is demodulated into a baseband signal, data is extracted from the baseband signal, and is output to the output terminal 8. Further, when the data reception ends, the wireless reception circuit 6 generates a data reception end signal and outputs it to the controller 7.

  In the radio signal reception process of FIG. 2, first, in step S1, the switch 3a is turned off and the application of the control voltage V to the phase shifter 2a is turned off. Next, in step S2, based on the detection signal from the power detection circuit 5, it is determined whether or not the received power P of the radio signal received by the antenna element 1a is equal to or greater than a predetermined threshold value. If YES, the process proceeds to step S3. If NO, the process of step S2 is repeated. Here, the predetermined threshold value is compared with a noise level that is a reception power level of a radio signal received by the antenna element 1a when a reception signal has not arrived (hereinafter referred to as a reception signal non-arrival). Thus, it is a large value, and preferably a value twice the noise level.

  In step S3, the switch 3a is turned on and the control voltage V is applied to the phase shifter 2a, so that a two-element linear array antenna is constituted by the array elements 1a and 1b. Further, in step S4, the control voltage V is increased linearly, for example, discretely with respect to time, and the data of each received power P for each control voltage V is stored in the received power memory 7m. Here, by increasing the control voltage V linearly with respect to time, the phase shift amount δ of the phase shifter 2a increases linearly between −90 degrees and 90 degrees, and the main beam of the two-element linear array antenna The azimuth angle varies linearly between -90 degrees and 90 degrees. Therefore, the data stored in the received power memory 7m in step S4 is data indicating the relationship between each control voltage V corresponding to each azimuth of the main beam of the two-element linear array antenna and each received power P. In this specification, the azimuth angle is measured clockwise from a direction perpendicular to the longitudinal direction of the linear array antenna on a plane on which a planar antenna element such as a patch antenna element constituting the linear array antenna is formed. Angle.

  Next, in step S5, based on the received power P data stored in step S4, a control voltage Vmax when the received power is substantially maximum is calculated, and in step S6, the phase shifter 2a is calculated. By applying the control voltage Vmax, the main beam of the two-element linear array antenna is directed in the direction of the incoming received signal, which is the azimuth angle at which the received power is substantially maximum. In step S7, a data reception start signal is generated and transmitted to the wireless reception circuit 6. In step S8, it is determined whether or not a data reception end signal has been received from the wireless reception circuit 6. If YES, the process returns to step S1, while if NO, the process of step S8 is repeated.

  In the array antenna apparatus of FIG. 1, the antenna elements 1a and 1b are formed on a substrate having a relative dielectric constant of 2.2 and a thickness of 0.5 mm, respectively, and a square patch having a patch of 1.28 mm × 1.28 mm. A simulation result of directivity when the antenna is used, the frequency of the radio signal is 60 GHz, and the interval between the antenna elements 1a and 1b is a half wavelength of the radio signal is shown below. 4 is a directivity characteristic diagram of the antenna element 1a alone in FIG. 1, and FIG. 5 is a two-element linear when the switch 3a is turned on in FIG. 1 and the phase shift amount δ of the phase shifter 2a is 0 degree. FIG. 6 is a directional characteristic diagram of the two-element linear array antenna when the switch 3a is turned on in FIG. 1 and the phase shift amount δ of the phase shifter 2a is 75 degrees. As can be seen from FIGS. 4 and 5, the half width of the main beam of the antenna element 1a alone is about 80 degrees, but by using a two-element linear array antenna, the half width of the main beam is about half and Gain is rising. Further, as apparent from FIGS. 5 and 6, by changing the phase shift amount δ of the phase shifter 2a from 0 degree to 75 degrees, the azimuth angle of the main beam changes by about 20 degrees. That is, by turning on the switch 3a, the width of the main beam of the array antenna apparatus of FIG. 1 can be narrowed and the gain can be increased as compared to when the switch 3a is turned off. By changing it, the azimuth angle of the main beam of the array antenna apparatus of FIG. 1 can be changed.

  According to the array antenna apparatus configured as described above, when the received signal has not arrived, the switch 3a is turned off and the application of the control voltage V to the phase shifter 2a is turned off to receive the antenna element 1a alone. Since it is determined whether or not a received signal has arrived based on the received power level of the radio signal, the power consumption is smaller than that of the prior art. Further, when it is determined that the received signal has arrived (hereinafter referred to as the received signal), the switch 3a is turned on and the control voltage V is applied to the phase shifter 2a, and the antenna elements 1a and 1b are configured. Since a high-gain two-element linear array antenna is used as compared with the antenna element 1a, the received power is larger and the communication quality is higher than when the received signal does not arrive. Furthermore, when the received signal arrives, the control voltage V applied to the phase shifter 2a is increased linearly with respect to time, so that the phase shifter 2a is controlled based on the radio signal received by the two-element linear array antenna. Since the phase shift amount δ is changed linearly and the phase shifter 2a is controlled so that the main beam of the linear array antenna faces the direction of the received signal, the amount of calculation is less than that of the prior art.

  In the above embodiment, the antenna elements 1a and 1b are patch antennas. However, the present invention is not limited to this and may be other planar antennas.

Modification of the first embodiment.
FIG. 3 is a block diagram showing a configuration of an array antenna apparatus according to a modification of the first embodiment. The array antenna apparatus according to the modified example of the first embodiment of FIG. 3 includes a radio reception circuit 6A and a controller 7A instead of the radio reception circuit 6 and the controller 7 as compared with the array antenna apparatus of FIG. The direction of the incoming received signal is estimated based on a bit error rate (hereinafter referred to as BER) which is the signal quality of the later baseband signal. Hereinafter, differences from the first embodiment will be described in detail. The characteristic configuration of the modified example of the first embodiment can be applied to other embodiments described later.

  In FIG. 3, the radio reception circuit 6 </ b> A is characterized by including a signal quality measuring device 61 as compared with the radio reception circuit 6 of FIG. 1. The signal quality measuring device 61 measures the BER, which is the signal quality of the demodulated baseband signal, and outputs a signal indicating the measured BER to the controller 7A. Here, in the radio signals received by the antenna elements 1a and 1b, a thermal noise component is usually received together with the desired wave signal. Furthermore, a co-channel interference wave of the same frequency from an adjacent base station or a delayed wave that is a desired wave but has a time delay due to arrival through a large path may be received. In analog radio communication systems such as television broadcasting and radio broadcasting, the delayed wave deteriorates the quality of screen display as a ghost displayed on, for example, a television receiver. On the other hand, in a digital wireless communication system, thermal noise, co-channel interference waves and delayed waves all affect as bit errors and directly degrade signal quality. Here, if the desired wave carrier power is C, the thermal noise power is N, and the interference wave power including the co-channel interference wave and the delayed wave is I, the controller 7A in FIG. 3 preferably improves the signal quality. Therefore, in order to substantially maximize the carrier-to-noise and interference wave power ratio C / (N + I), the main beam of the two-element array antenna is directed in the direction in which the BER is minimized.

  As described above, according to the modification of the first embodiment, in addition to the operation and effect of the first embodiment, reception that arrives in a direction in which the carrier-to-noise and interference wave power ratio is substantially maximized. By setting the signal direction, the communication quality is higher than that of the first embodiment even when an interference wave exists.

  In the above modification, in order to substantially maximize the carrier-to-noise and interference wave power ratio C / (N + I), the direction in which the BER is the minimum is the direction of the incoming received signal. However, the direction of the received signal may be a direction in which the packet error rate (Packet Error Rate; hereinafter referred to as PER) is minimized.

Second embodiment.
FIG. 7 is a block diagram showing a configuration of the array antenna apparatus according to the second embodiment. The array antenna apparatus according to the modification of the second embodiment of FIG. 7 includes a controller 7B instead of the controller 7 as compared with the array antenna apparatus of FIG. 1, and includes antenna elements 1b to 1e and a phase shifter 2b. To 2e and adders 82 to 84 that are adders, and based on a radio signal received by a five-element linear array antenna configured to include array elements 1a to 1e when a received signal arrives, The phase shifters 2a to 2e are controlled so that the main beam of the 5-element linear array antenna is directed to the direction of the received signal. Hereinafter, differences from the first embodiment will be described in detail.

  In FIG. 7, antenna elements 1a to 1e are patch antennas having the same directivity characteristics, and are juxtaposed on the same straight line at intervals of half wavelengths of radio signals received by the array antenna apparatus of FIG. Further, each of the phase shifters 2a to 2d is a DC voltage control type phase shifter, and when the same control voltage V is applied from the controller 7B, the phase of the input signal is changed to a predetermined same phase shift. Change by an amount δ. The radio signal received by the antenna 1e is output to the combiner via the phase shifter 2d, and the adder 84 combines the radio signal from the phase shifter 2d and the radio signal received by the antenna 1d. The data is output to the synthesizer 83 via the phase shifter 2c. Furthermore, the synthesizer 83 synthesizes the radio signal from the phase shifter 2c and the radio signal received by the antenna 1c and outputs the synthesized signal to the synthesizer 82 via the phase shifter 2b. Furthermore, the synthesizer 82 synthesizes the radio signal from the phase shifter 2b and the radio signal received by the antenna 1b and outputs the synthesized signal to the synthesizer 81 via the phase shifter 2a and the switch 3a. Then, the synthesizer 81 synthesizes the radio signal input via the switch 3a and the radio signal received by the antenna element 1a, and the power detection circuit 5 and the radio reception circuit 6 via the directional coupler 4. Output to.

  Similarly to the first embodiment, the controller 7B turns off the switch 3a when the received signal does not arrive and turns off the application of the control voltage V to the phase shifters 2a to 2d, and is received by the antenna element 1a. It is determined whether a received signal has arrived based on the received power level of the radio signal. On the other hand, when the received signal arrives, the switch 3a is turned on and the control voltage V is applied to the phase shifters 2a to 2d, and the received power level of the radio signal received by the 5-element linear array antenna comprising the array elements 1a to 1e. As in the first embodiment, the phase shifters 2a to 2d are controlled so that the main beam of the 5-element linear array antenna faces the direction of the received signal.

  In the array antenna apparatus of FIG. 7, each of the antenna elements 1a to 1e is formed on a substrate having a relative dielectric constant of 2.2 and a thickness of 0.5 mm, and the patch has a square patch of 1.28 mm × 1.28 mm. A simulation result of directivity when the antenna is used, the frequency of the radio signal is 60 GHz, and the interval between the antenna elements 1a and 1b is a half wavelength of the radio signal is shown below. FIG. 8 is a directional characteristic diagram of the 5-element linear array antenna when the switch 3a is turned on in FIG. 7 and the phase shift amounts δ of the phase shifters 2a to 2d are set to 0 degrees. 5 is a directional characteristic diagram of the 5-element linear array antenna when the switch 3a is turned on and the phase shift amounts δ of the phase shifters 2a to 2d are set to 45 degrees. As apparent from FIGS. 5 and 8, the main beam of the five-element linear array antenna has a narrower half-value width and a higher relative gain than the main beam of the two-element linear array antenna of the first embodiment. Yes. Further, as is clear from FIGS. 8 and 9, by changing the phase shift amounts δ of the phase shifters 2a to 2d from 0 degrees to 45 degrees, the half width and relative width of the main beam of the 5-element linear array antenna are changed. The gain does not change and the azimuth angle changes by 25 degrees. That is, the azimuth angle of the main beam of the array antenna apparatus of FIG. 7 can be changed by changing the phase shift amounts δ of the phase shifters 2a to 2e.

  As described above, according to the second embodiment, in addition to the effects of the first embodiment, the radio signal received by the five-element linear array antenna including the array elements 1a to 1e when the received signal arrives. As in the first embodiment, the phase shifters 2a to 2d are controlled so that the main beam of the five-element linear array antenna is directed to the direction of the received signal based on the received power level. The communication quality is higher than that of the array antenna apparatus of the embodiment. Although the number of phase shifters is increased as compared with the first embodiment, the application of the control voltage V to all the phase shifters 2a to 2d is turned off when the received signal has not arrived. And power consumption is small.

Third embodiment.
FIG. 10 is a block diagram showing a configuration of a narrow beam detection type array antenna apparatus according to the third embodiment. The array antenna apparatus according to the modification of the third embodiment of FIG. 10 includes a controller 7C instead of the controller 7B and a phase shift with the antenna element 1b instead of the switch 3a, as compared with the array antenna apparatus of FIG. Whether or not the received signal has arrived using a two-element linear array antenna comprising the antenna elements 1a and 1b when the received signal has not yet arrived. It is characterized by having been judged. Hereinafter, differences from the second embodiment will be described in detail.

  The controller 7C turns off the switch 3b when the received signal does not arrive and turns off the application of the control voltage V to the phase shifters 2b to 2d, turns on the switch 3b when the received signal arrives, and performs the second implementation. The control voltage V is applied to the phase shifters 2a to 2d as in the embodiment. Here, when the received signal does not arrive, the radio signal received by the two-element linear array antenna composed of the array elements 1a and 1b is transmitted to the directional coupler, as in the case of the received signal in the first embodiment. 4 to the power detection circuit 5 and the wireless reception circuit 6. On the other hand, when the received signal arrives, similarly to the time when the received signal arrives in the second embodiment, the radio signal received by the five-element linear array antenna including the array elements 1a to 1e passes through the directional coupler 4. Via the power detection circuit 5 and the wireless reception circuit 6.

  By configuring the array antenna apparatus as described above, it is determined whether or not the received signal has arrived based on the received power level of the radio signal received by the two-element linear array antenna when the received signal has not yet arrived. Compared to the first embodiment using one antenna element 1a, the relative gain is high when the received signal has not yet arrived (see FIGS. 5 and 8), and the received signal from a farther transmitting station is received. It can be detected by the power detection circuit 5. The array antenna apparatus of FIG. 10 is useful when the direction of the incoming received signal is within a predetermined range and the half width of the main beam may be relatively narrow when the received signal has not arrived.

  Further, since the application of the control voltage V to the phase shifter 2a is not turned off when the received signal has not arrived, the power consumption is larger than that of the second embodiment, but the control to the phase shifters 2b to 2d is performed. Since the application of the voltage V is turned off, the power consumption is small as compared with the prior art.

Fourth embodiment.
FIG. 11 is a block diagram showing a configuration of a grating lobe detection type array antenna apparatus according to the fourth embodiment. An array antenna apparatus according to a modification of the fourth embodiment of FIG. 11 includes a controller 7D instead of the controller 7C and an antenna element 1a and an antenna instead of the switch 3b, as compared with the array antenna apparatus of FIG. A switch 3c for directly connecting the antenna element 1e farthest from the element 1a and a switch 3d inserted between the antenna element 1e and the phase shifter 2d are received by the antenna 1a. A two-element device including a combiner that combines a wireless signal and a wireless signal received by the antenna 1e and outputs the combined signal to the directional coupler 4, and includes the array elements 1a and 1e when no received signal arrives. It is characterized by determining whether or not a received signal has arrived using a linear array antenna. Hereinafter, differences from the third embodiment will be described in detail.

  The controller 7D turns off the switches 3a and 3d and turns on the switch 3c when no received signal arrives, turns off the application of the control voltage V to the phase shifters 2a to 2d, and turns off the switches 3a and 3d when the received signal arrives. 3d is turned on and the switch 3c is turned off, and the control voltage V is applied to the phase shifters 2a to 2d as in the third embodiment. Here, when the reception signal has not arrived, the radio signal received by the two-element linear array antenna including the array elements 1 a and 1 e is output to the power detection circuit 5 and the radio reception circuit 6 via the directional coupler 4. Is done. On the other hand, when the received signal arrives, similarly to the time when the received signal arrives in the third embodiment, the radio signal received by the five-element linear array antenna including the array elements 1a to 1e passes through the directional coupler 4. Via the power detection circuit 5 and the wireless reception circuit 6.

  By configuring the array antenna apparatus as described above, the antenna element interval of the two-element linear array antenna used when the received signal has not arrived is longer than that of the third embodiment, and thus has a narrow band characteristic. It becomes an array antenna device. Further, since the application of the control voltage V to the phase shifters 2a to 2d is turned off when the received signal has not arrived, the power consumption is small compared to the prior art.

  In each of the second to fourth embodiments described above, the antenna elements 1a to 1e are configured by the antenna elements 1a to 1e when the received signal arrives. However, the present invention is not limited to this, and the antenna elements 1a to 1e are not limited thereto. The intervals may not be equal. In this case, the phase shift amounts of the phase shifters 2a to 2d are different values based on the distance between the antenna elements 1a to 1e.

Fifth embodiment.
FIG. 12 is a block diagram showing a configuration of a two-dimensional array antenna apparatus according to the fifth embodiment. An array antenna apparatus according to a modification of the fourth embodiment in FIG. 11 includes a controller 7E instead of the controller 7 as compared with the array antenna apparatus in FIG. 1, and a two-dimensional array antenna is provided when a received signal arrives. It is used. Hereinafter, differences from the first embodiment will be described in detail.

  12, the array antenna apparatus according to the fifth embodiment includes 25 antenna elements 11 to 15, 21 to 25, 31 to 35, 41 to 45, and 51 to 55, and 24 phase shifters 11a to 11a. 14a, 21a-25a, 31a-35a, 41a-45a and 51a-55a, switches 71 and 72, directional coupler 4, power detection circuit 5, wireless reception circuit 6, controller 7E, and output terminal 8 and is configured. In FIG. 12, the sushi of the combiner that combines the radio signal received by each antenna element and the radio signal from each phase shifter is omitted.

  In FIG. 12, antenna elements 11 to 15, 21 to 25, 31 to 35, 41 to 45, and 51 to 55 each have the same directivity characteristic, and are half wavelengths of radio signals received by the array antenna apparatus of FIG. Are juxtaposed in a two-dimensional matrix shape having two axes orthogonal to each other. Moreover, the phase shifters 11a-14a, 21a-25a, 31a-35a, 41a-45a, and 51a-55a are connected in series between each adjacent antenna element, as shown in FIG. Here, each of the phase shifters 11a to 14a is a DC voltage control type phase shifter, and when the controller 7 is applied with the control voltage V1, the phase of the input signal is set by a predetermined phase shift amount δ1. The phase shifters 21a to 25a, 31a to 35a, 41a to 45a, and 51a to 55a are DC voltage control type phase shifters, and are input by applying a control voltage V2 from the controller 7. The phase of the signal is changed by a predetermined phase shift amount δ2. Further, the switch 71 is inserted between the antenna element 11 and the antenna element 12, and the switch 72 is inserted between the antenna element 11 and the antenna element 21. Here, the switches 71 and 72 are interlocked.

  In FIG. 12, the controller 7E turns off the switches 71 and 72 when the received signal has not arrived, and the control voltages to all the phase shifters 11a to 14a, 21a to 25a, 31a to 35a, 41a to 45a, and 51a to 55a. When the application of V1 or V2 is turned off and the received signal arrives, the switches 71 and 72 are turned on, and the control voltage V1 or V2 is applied to the phase shifters 11a to 14a, 21a to 25a, 31a to 35a, 41a to 45a, and 51a to 55a. Apply. Here, when the switches 71 and 72 are off, the radio signal received by the antenna element 11 is output to the power detection circuit 5 and the radio reception circuit 6 via the directional coupler 4. On the other hand, when the switches 71 and 72 are on, the radio signals received by the two-dimensional array antenna including the antenna elements 11 to 15, 21 to 25, 31 to 35, 41 to 45, and 51 to 55 are directional coupled. The power is output to the power detection circuit 5 and the wireless reception circuit 6 via the device 4.

  In FIG. 12, the controller 7E estimates the direction of the received signal that arrives in a three-dimensional manner by the following method when the received signal arrives. First, the control voltage V1 applied to the phase shifters 11a to 14a is increased, for example, discretely and linearly with respect to time, and data of each received power P for each control voltage V1 is stored in the received power memory 7m. Next, based on the stored data of received power P, a control voltage V1max when the received power is substantially maximum is calculated, and the control voltage V1max is applied to the phase shifters 11a to 14a. Further, the control voltage V2 applied to the phase shifters 21a to 25a, 31a to 35a, 41a to 45a, and 51a to 55a is increased linearly with respect to time with the control voltage V1max applied to the phase shifters 11a to 14a. Then, the data of each received power P for each control voltage V2 is stored in the received power memory 7m. Then, based on the stored data of received power P, a control voltage V2max when the received power is substantially maximum is calculated, and the control voltage V2max is converted into phase shifters 21a-25a, 31a-35a, 41a- Apply to 45a and 51a-55a. As a result, the main beam of the two-dimensional array antenna is directed in the direction of the incoming received signal.

  As described above, according to the fifth embodiment, in addition to the effects of the first embodiment, the direction of the received signal that arrives using the two-dimensional array antenna when the received signal arrives is estimated in three dimensions. As a result, the communication quality is higher than that of the array antenna apparatus of the first embodiment. Further, although the number of phase shifters is increased as compared with the first embodiment, all of the phase shifters 11a to 14a, 21a to 25a, 31a to 35a, 41a to 45a, and 51a to 55a are received when the received signal does not arrive. Since the control voltage V1 or V2 is turned off, the power consumption is smaller than that of the prior art.

  In the above embodiment, it is determined whether or not a received signal has arrived based on the power level of the radio signal received by one or two antenna elements. However, the present invention is not limited to this, and the array is not limited to this. A part of the antenna elements constituting the entire antenna device may be used, and the number of antenna elements used may be three or more. In the above embodiment, an array antenna including two, five, or twenty-five antenna elements is used when a received signal arrives. However, the present invention is not limited to this, and other numbers of antenna elements are used. An array antenna may be configured. Furthermore, in the above embodiment, the antenna elements constituting the array antenna apparatus are juxtaposed in a linear or two-dimensional matrix shape. However, the present invention is not limited to this, and a circumferential shape, a triangular shape, a cylindrical shape, etc. It may be juxtaposed in other shapes.

  As described in detail above, according to the array antenna device of the present invention, in the array antenna device in which at least one first antenna element and at least one antenna element are juxtaposed in a predetermined arrangement shape, Based on at least one switch means connected between the antenna element and the second antenna element and the applied control signal, a radio signal received by the second antenna element is transmitted by a predetermined phase shift amount. A phase shifter for phase shifting, a detection unit, and a control unit, wherein the detection unit detects a first received power level of a radio signal received by the first antenna element when the switch unit is on; A first detection signal indicating the first received power level is generated and output. When the switch means is off, a radio signal received by the first antenna element and a phase shifter are output. Combining the radio signal, detecting the second received power level of the synthesized array antenna radio signal, generating and outputting a second detection signal indicating the second received power level, and the control means When the switch means is turned off and the control signal applied to the phase shifter is turned off, it is determined whether the received signal has arrived based on the first detection signal, and when it is determined that the received signal has arrived, Since the switch means is turned on and a control signal is output to the phase shifter, the phase shifter is controlled based on the radio signal of the array antenna so that the main beam of the array antenna is directed to the incoming signal. Power consumption is small compared to, and the amount of calculation is small.

It is a block diagram which shows the structure of the array antenna apparatus which concerns on 1st Embodiment. It is a flowchart which shows the radio signal reception process performed by the controller 7 of FIG. It is a block diagram which shows the structure of the array antenna apparatus which concerns on the modification of 1st Embodiment. FIG. 2 is a directional characteristic diagram of a single antenna element 1a in FIG. FIG. 3 is a directional characteristic diagram of a two-element linear array antenna when a switch 3a is turned on in FIG. 1 and a phase shift amount δ of the phase shifter 2a is 0 degree. FIG. 3 is a directional characteristic diagram of a two-element linear array antenna when a switch 3a is turned on in FIG. 1 and a phase shift amount δ of the phase shifter 2a is 75 degrees. It is a block diagram which shows the structure of the array antenna apparatus which concerns on 2nd Embodiment. FIG. 8 is a directional characteristic diagram of a 5-element linear array antenna when a switch 3a is turned on in FIG. 7 and each phase shift amount δ of the phase shifters 2a to 2d is set to 0 degree. FIG. 8 is a directional characteristic diagram of a 5-element linear array antenna when a switch 3a is turned on in FIG. 7 and each phase shift amount δ of the phase shifters 2a to 2d is 45 degrees. It is a block diagram which shows the structure of the narrow beam detection type | mold array antenna apparatus which concerns on 3rd Embodiment. It is a block diagram which shows the structure of the grating lobe detection type | mold array antenna apparatus which concerns on 4th Embodiment. It is a block diagram which shows the structure of the two-dimensional array antenna apparatus which concerns on 5th Embodiment.

Explanation of symbols

1a to 1e ... antenna element,
2a to 2d ... phase shifter,
3a to 3d ... switch,
4 ... Directional coupler,
5 ... Power detection circuit,
6, 6A ... wireless receiving circuit,
7, 7A-7E ... controller,
7m ... Received power memory,
8: Output terminal,
11-15, 21-25, 31-35, 41-45, 51-55 ... antenna elements,
11a-14a, 21a-25a, 31a-35a, 41a-45a, 51a-55a ... phase shifter,
71, 72 ... switches,
81-85 ... Synthesizer.

Claims (7)

In an array antenna device in which at least one first antenna element and at least one second antenna element are juxtaposed in a predetermined arrangement shape,
At least one switch means connected between the first antenna element and the second antenna element;
A phase shifter that shifts a radio signal received by the second antenna element by a predetermined phase shift amount based on an applied control signal;
When the switch means is on, the first received power level of the radio signal received by the first antenna element is detected, and a first detection signal indicating the first received power level is generated and output. When the switch means is off, the radio signal received by the first antenna element and the radio signal output from the phase shifter are combined, and the second radio signal of the combined array antenna is synthesized. Detecting means for detecting a received power level of the second and generating and outputting a second detection signal indicating the second received power level;
The switch means is turned off and the control signal applied to the phase shifter is turned off. Based on the first detection signal, it is determined whether a received signal has arrived, and it is determined that the received signal has arrived. Then, the switch means is turned on and a control signal is output to the phase shifter, and the phase shift is performed so that the main beam of the array antenna is directed to the direction of the received signal based on the radio signal of the array antenna. An array antenna apparatus comprising control means for controlling the detector. A plurality of second antenna elements;
A plurality of phase shifters inserted between feed points of the second antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna 2. The array antenna apparatus according to claim 1, wherein each of the phase shifters is controlled so as to be oriented toward the center. A plurality of first antenna elements;
A plurality of phase shifters inserted between the feed points of the first antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna 2. The array antenna apparatus according to claim 1, wherein each of the phase shifters is controlled so as to be oriented toward the center. A plurality of first antenna elements;
A plurality of second antenna elements;
A plurality of phase shifters inserted between the feed points of the first antenna elements adjacent to each other;
A plurality of phase shifters inserted between feed points of the second antenna elements adjacent to each other;
The control means turns off the switch means and turns off a control signal applied to each phase shifter, determines whether or not a received signal has arrived based on the first detection signal, and receives the received signal. When it is determined that a signal has arrived, the switch means is turned on and a control signal is output to each phase shifter, and the direction of the received signal from which the main beam of the array antenna arrives based on the radio signal of the array antenna 2. The array antenna apparatus according to claim 1, wherein each of the phase shifters is controlled so as to be oriented toward the center.   When the control means determines that the received signal has arrived, it turns on the switch means and outputs a control signal to each phase shifter, so that the second received power level of the radio signal of the array antenna is substantially equal. 5. Each of the phase shifters is controlled so as to be a maximum value and to be directed in a direction of a received signal from which the main beam of the array antenna arrives. The array antenna apparatus described.   When it is determined that the received signal has arrived, the control means turns on the switch means and outputs a control signal to each phase shifter, and the carrier-to-noise and interference wave power ratio of the radio signal of the array antenna 5. Each of the phase shifters is controlled so that becomes substantially the maximum value and is directed to the direction of the received signal from which the main beam of the array antenna arrives. Array antenna device according to claim 1. The array according to any one of claims 1 to 6, wherein each of the first antenna elements and each of the second antenna elements are juxtaposed at a half wavelength interval of the radio signal. Antenna device.

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