JP4925949B2 - Optically controlled phased array antenna device - Google Patents

Description

  The present invention relates to an optically controlled phased array antenna device for controlling a microwave beam radiated from an array antenna by light waves.

  The first beam light and the second beam light whose frequency is detuned by the frequency of the microwave are radiated, the intensity distribution is given by an image mask using the first beam light as a signal light beam, and then by a Fourier transform lens. The power is supplied to each antenna element of the array antenna and converted into amplitude and phase distribution. Further, the second light beam is used as a local light beam, the signal light beam and the local light beam are spatially superimposed and spatially sampled, and the sampling light is demodulated into microwaves by heterodyne detection using a photoelectric conversion element. After that, it is radiated to the space using an array antenna (for example, see Patent Document 1).

JP-A-3-44202

  However, in such a light control type phased array antenna device, the wavefront of the light wave fluctuates due to, for example, a lens position shift, a beam synthesizer, a mirror, etc. due to temperature change and vibration of the environment where the device is placed, There is a problem that the direction and shape of the microwave beam emitted from the array antenna varies.

  An object of the present invention is to provide an optically controlled phased array antenna device that controls a microwave beam radiated from an array antenna in a desired direction even when an optical system fluctuates due to temperature, vibration, or the like.

The light control type phased array antenna device according to the present invention emits a first signal light beam and a first local light beam detuned from the first signal light beam by a frequency of a first microwave. A first microwave-light output device that emits to a space different from the space from which the first signal light beam is emitted; and a second signal light in a space different from the space from which the first signal light beam is emitted. while emitting a beam, the second second local light beam the second signal light beams from the signal beam to detuning by the frequency of said first microwave frequency and a different second microwave is A second microwave-light output device that emits to a space different from the emitted space, and a spatial light intensity change that modulates the intensity of the first signal light beam and the spatial intensity distribution of the second signal light beam. A Fourier transform lens that spatially Fourier transforms the first signal light beam and the second signal light beam modulated by the spatial light intensity modulator, the first local light beam, and the second A first beam combiner that spatially combines a local light beam into a combined local light beam, and the Fourier-transformed first signal light beam and second signal light beam are combined with the combined local light beam and space. A second beam synthesizer that is combined into a combined light beam, an optical sampling array composed of a plurality of fibers that spatially sample the combined light beam, and the first micro-beam from each output of the fiber. A plurality of first demodulation means for demodulating the wave, and an array antenna for radiating the first microwave demodulated by the plurality of first demodulation means to space. In the control-type phased array antenna apparatus, the second microwave is demodulated from two phase monitor fibers for sampling the combined light beam at two positions separated on a straight line, and outputs of the phase monitor fibers. From two second demodulating means, a phase comparator for outputting a phase difference between the second microwaves demodulated by the two second demodulating means as a DC electrical signal, and a DC electrical signal of the phase comparator A computing device that computes a difference in inclination of one wavefront of the second signal light beam and the second local light beam on one line; and the second signal light beam based on a computation result of the computing device; The first signal light beam and the second signal light beam or the second signal light beam or the second local light beam so that a difference in inclination on one line of the wavefront with the second local light beam converges to a predetermined value. Wavefront correction means for controlling the combined local light beam.

  The effect of the optically controlled phased array antenna device according to the present invention is that the two second microwaves are demodulated from the combined light beam received by the phase monitoring fiber, and the phase difference between the demodulated two second microwaves is Since the first local light beam and the second local light beam are phase-modulated in the direction opposite to the phase fluctuation direction so as to converge to a predetermined value, the desired direction can be obtained even if the optical system fluctuates due to temperature, vibration, etc. The beam can be controlled.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of an optically controlled phased array antenna device according to Embodiment 1 of the present invention.
As shown in FIG. 1, the optically controlled phased array antenna device according to the first embodiment of the present invention is detuned by the frequency of the first microwave input from the first microwave input terminal 2. Of the first microwave-light output device 1 for emitting the signal light beam 3 and the first local light beam 4 to the free space, and the second microwave input from the second microwave input terminal 7. A second microwave-light output device 6 that emits the second signal light beam 8 and the second local light beam 9 detuned by the frequency to free space is provided.

  If a Mach-Zehnder type optical modulator is used as the first microwave-light output device 1 and the second microwave-light output device 6, the frequency is equal to the frequency of the microwave input by externally modulating the laser light. Can be easily generated, and each light beam can be easily formed by an optical system such as a lens.

The optical control type phased array antenna device according to Embodiment 1 of the present invention is
A spatial light intensity modulation device (hereinafter referred to as “A-SLM”) that receives the first signal light beam 3 and the second signal light beam 8 and modulates the intensity of the spatial intensity distribution by the input first control signal. 10, a spatial light intensity modulation device driver 11 that outputs a first control signal to the A-SLM 10, the first signal light beam 3 and the second signal light beam that are intensity-modulated by the A-SLM 10. The Fourier transform lens 15 that Fourier transforms 8, the first local light beam 4 emitted from the first microwave-light output device 1 and the optical path of which is adjusted by a mirror or the like, and the second microwave-light output device 6 A first beam combiner 17 that spatially combines the second local light beam 9 that has been emitted and whose optical path has been adjusted by a mirror or the like into a combined local light beam 18, and a combined local light beam Spatial light phase modulator for performing phase modulation on the spatial phase distribution of the beam 18 (hereinafter, abbreviated as "P-SLM") a 12.

The optical control type phased array antenna device according to Embodiment 1 of the present invention is
A second beam combiner 16 that combines the Fourier-transformed first signal light beam 3 and second signal light beam 8 with a combined local light beam 18 to form a combined light beam 19, and a second beam combiner 16 includes an optical sampling array 20 on which the combined light beam 19 combined at 16 is incident on the light receiving surface.

  The exit surfaces of the first signal light beam 3 and the second signal light beam 8 of the A-SLM 10 are the front focal plane of the Fourier transform lens 15, and the light receiving surface of the optical sampling array 20 is the rear focal plane of the Fourier transform lens 15. Install in. When installed in this manner, a Fourier transform relationship is established between the exit surface of the A-SLM 10 and the light receiving surface of the optical sampling array 20. Therefore, a Fourier transform image of the first signal light beam 3 and the second signal light beam 8 intensity-modulated by the A-SLM 10 is formed on the light receiving surface of the optical sampling array 20.

The second beam combiner 16 spatially superimposes the first signal light beam 3 and the combined local light beam 18, and the second signal light beam 8 and the combined local light beam 18.
The optical sampling array 20 has a plurality of fibers, and samples the combined light beam 19 incident on the light receiving surface of each fiber.

  Further, the optically controlled phased array antenna device according to Embodiment 1 of the present invention is a photoelectric conversion element 21 that converts the combined light beam 19 received by the light receiving surface of each fiber of the optical sampling array 20 into a microwave by heterodyne detection. Of the first microwave and the second microwave output from each photoelectric conversion element 21, the first microwave filter 22 that transmits only the first microwave, the first power fed to the antenna element An array antenna 23 that radiates microwaves to space is provided. The photoelectric conversion element 21 and the first microwave filter 22 are collectively referred to as first demodulation means.

  Further, the optically controlled phased array antenna device according to the first embodiment of the present invention includes two fibers in the optical sampling array 20 (hereinafter, phase monitoring fibers 50a and 50b in order to distinguish them from other fibers). Of the first microwave and the second microwave generated in the photoelectric conversion element 21 (hereinafter, referred to as 51a and 51b to be distinguished from other photoelectric conversion elements 21) connected to A DC electric signal corresponding to the phase difference between the two second microwaves transmitted through the second microwave filters 52a and 52b and the second microwave filters 52a and 52b that transmit only the second microwave is output. Difference in inclination on the wavefront line between the second signal light beam 8 and the second local light beam 9 from the DC electric signals of the phase comparison device 53 and the phase comparison device 53 An arithmetic device 55 for calculating, and a control signal for phase-modulating the spatial phase distribution of the first local light beam 4 and the second local light beam 9 so that the difference in inclination on the wavefront line converges to a predetermined value Is provided to the P-SLM 12. The photoelectric conversion elements 51a and 51b and the second microwave filters 52a and 52b are collectively referred to as second demodulation means. The P-SLM 12 and the spatial phase controller 13 are collectively referred to as wavefront correction means.

  As the phase monitoring fibers 50a and 50b, two fibers on both sides in the vertical direction in the elements of the optical sampling array 20 are selected. By selecting in this way, the measurement resolution of the wavefront variation can be increased. Two fibers on both sides in the horizontal direction may be selected, or two fibers at arbitrary positions may be used.

The phase comparison device 53 can be realized by, for example, a double balanced mixer. When a microwave having the same frequency is input to the RF input port and the local input port of the double balance mixer, a DC corresponding to the phase difference between the two microwaves from the IF port. An electrical signal is output.
At this time, by superimposing a predetermined phase difference in advance between the RF input port and the local input port, the DC electric signal is output as 0 at the initial phase difference, that is, at the time of convergence, and the DC electric signal is output as positive or negative depending on whether the phase difference is positive or negative. You can also As a result, the target value 0 of the DC electrical signal does not depend on the RF and local input intensity, so that it can be applied even if intensity fluctuation occurs.

Next, the reason why the light control type phased array antenna device according to the first embodiment of the present invention can control the beam in a desired direction even if the optical system fluctuates due to temperature, vibration or the like will be described.
Four waves of the first signal light, the first local light, the second signal light, and the second local light received by each fiber of the optical sampling array 20 are respectively transmitted to the photoelectric conversion element 21 and subjected to heterodyne detection. Converted to microwaves.
Here, the intensity I _S1 (i) of the first signal light received by the fiber i of the optical sampling array 20 is expressed by Expression (1), the intensity I _L1 (i) of the first local light is expressed by Expression (2), The intensity I _S2 (i) of the signal light 2 is _expressed by Equation (3) and the intensity I _L2 (i) of the second local light is expressed by Equation (4).

I _S1 (i) = A ₁ (i) cos (ω _a1 t + φ _a1 (i)) (1)
I _L1 (i) = B ₁ (i) cos (ω _b1 t + φ _b1 (i)) (2)
I _S2 (i) = A ₂ (i) cos (ω _a2 t + φ _a2 (i)) (3)
I _L2 (i) = B ₂ (i) cos (ω _b2 t + φ _b2 (i)) (4)

Where A ₁ (i) and B ₁ (i) are the intensities of the first signal light and the first local light received by the fiber i, respectively, and ω _a1 and ω _b1 are the first signal light and the first local light, respectively. The angular frequency of light, φ _a1 (i), φ _b1 (i) is the phase of the first signal light and the first local light. Similarly, A ₂ (i) and B ₂ (i) are the intensities of the second signal light and the second local light received by the fiber i, respectively, and ω _a2 and ω _b2 are the second signal light and the second signal light, respectively. The angular frequencies of local light, φ _a2 (i), φ _b2 (i) are the phases of the second signal light and the second local light.

In each photoelectric conversion element 21, a difference component and a sum component of four waves of the first signal light, the first local light, the second signal light, and the second local light are generated. Here, the difference between the frequency of the first signal light and the first local light and the frequency of the second signal light and the second local light is sufficiently increased with respect to the response band of the photoelectric conversion element 21. For example, when detuning is several hundred GHz or more, the first signal light, the second signal light, the first signal light, the second local light, the first local light, the second signal light, The difference frequency components of the local light and the second local light are not responded by the photoelectric conversion element 21, but the first signal light, the second signal light, the first signal light, and the second local light are not received. The sum components of the first local light, the second signal light, and the first local light and the second local light are also not responded by the photoelectric conversion element 21.
As a result, as a signal in the microwave frequency band, the first microwave expressed by the formula (5) from the first signal light and the first local light, the second signal light, and the second local light are used. Two waves of the second microwave expressed by the formula (6) are generated from the light. In addition, in Formula (5) and Formula (6), constant terms such as the quantum efficiency of the photoelectric conversion element 21 are omitted.

A ₁ (i) · B ₁ (i) cos ((ω _a1 −ω _b1 ) t + (φ _a1 (i) −φ _b1 (i)) (5)
A ₂ (i) · B ₂ (i) cos ((ω _a2 −ω _b2 ) t + (φ _a2 (i) −φ _b2 (i)) (6)

Then, of the first microwave and the second microwave generated in each photoelectric conversion element 21, only the first microwave is arrayed by the first microwave filter 22 that transmits only the first microwave. Electric power is supplied to each antenna element of the antenna 23 and radiated to the space.
There is a Fourier transform relationship between the excitation amplitude / phase distribution to each element of the array antenna 23 and the antenna radiation pattern (far field). Here, if the element arrangement on the light receiving surface of the optical sampling array 20 and the antenna element arrangement of the array antenna 23 are similar, and the first local light beam 4 has an equiphase distribution, the microwaves that excite the antenna elements The phase distribution is equal to the phase distribution of the first signal light beam 3 on the light receiving surface of the optical sampling array 20.
Since there is a Fourier transform relationship between the light receiving surface of the optical sampling array 20 and the exit surface of the A-SLM 10, the intensity distribution of the first signal light beam 3 on the exit surface of the A-SLM 10 is an array antenna. The radiation pattern from 23 is obtained.

  However, when the wave front of the first signal light beam 3 or the first local light beam 4 is tilted on the light receiving surface of the optical sampling array 20 due to distortion of the optical system due to disturbance such as temperature fluctuation or vibration, positional deviation, etc. The beam radiated from the array antenna 23 is also tilted.

  Therefore, the light is received by the two phase monitoring fibers 50a and 50b, the first microwave and the second microwave are generated by the photoelectric conversion elements 51a and 51b, and the second microwave filters 52a and 52b are used to generate the second microwave. Only the microwave is transmitted, the phase comparison device 53 obtains the phase difference between the two second microwaves, and the computing device 55 calculates the wavefront inclination of the second signal light beam 8 and the second local light beam 9 from the phase difference. The difference is calculated, and the phase difference in the spatial phase distribution of the second local light beam 9 is calculated so that the difference in wavefront inclination between the second signal light beam 8 and the second local light beam 9 becomes a predetermined value by the P-SLM 12. Modulate.

Here, when the intensity distribution of the second signal light beam 8 by the A-SLM 10 is fixed, the phase difference of the second microwave from the light received by the phase monitoring fibers 50a and 50b becomes a constant value. The phase difference from the phase comparator 53 is also constant.
On the other hand, when the second signal light beam 8 or the second local light beam 9 is inclined on the light receiving surface of the optical sampling array 20 due to distortion or positional deviation in the optical system due to disturbance such as temperature fluctuation or vibration, each beam Microwave phase fluctuations equal to the phase difference of. By obtaining the fluctuation of the phase difference of the microwaves received and demodulated by the phase monitoring fibers 50a and 50b by the phase comparator 53, the difference in the wavefront inclination between the second signal light beam 8 and the second local light beam 9 is obtained. Fluctuations can be obtained.
Accordingly, the P-SLM 12 causes the first local light beam 4 so that the phase difference between the second signal light beam 8 and the second local light beam 9 obtained by the phase comparator 53 is converged to a predetermined value. The phase distribution of the second local light beam 9 is phase-modulated in the direction opposite to the fluctuation direction of the phase difference between each signal light beam and the local light beam, so that the optical system fluctuates due to temperature, vibration, etc. Can also control the beam in the desired direction.

  Thus, the light received by the two fibers designated for phase monitoring in the optical sampling array 20 is converted into two second microwaves, and the phase difference between the two converted second microwaves is a predetermined value. Since the phase modulation is performed in the direction opposite to the phase fluctuation direction of the first local light beam 4 and the second local light beam 9 so as to converge to the value, even if the optical system fluctuates due to temperature, vibration, etc., the desired direction The beam can be controlled.

Note that elements connected to the array antenna 23 may be used as the phase monitoring fibers 50a and 50b. In this case, the signal may be branched for antenna feeding and phase monitoring before or after the photoelectric conversion element 21.
In the first embodiment, the transmissive A-SLM 10 and the P-SLM 12 are used. However, both may be formed of a reflective A-SLM and a P-SLM.

Embodiment 2. FIG.
FIG. 2 is a diagram showing a configuration of an optically controlled phased array antenna device according to Embodiment 2 of the present invention.
The light control type phased array antenna device according to the second embodiment of the present invention includes the light control type phased array antenna device according to the first embodiment, the first microwave-light output device 1B, and the second microwave-light output. The difference is that the device 6B has a first optical filter 25 and second optical filters 56a and 56b instead of the first microwave filter 22 and the second microwave filters 52a and 52b. Other than that, the same reference numerals are attached to the same parts, and the description thereof is omitted.

The first microwave-light output device 1B and the second microwave-light output device 6B emit the first signal light beam 3 and the second signal light beam 8 having wavelengths set in different bands. .
Further, the first microwave-light output device 1B and the second microwave-light output device 6B have a frequency difference between the first signal light beam 3 and the first local light beam 4, that is, the first microwave. And the frequency difference between the second signal light beam 8 and the second local light beam 9, that is, the frequency of the second microwave are set in the same band.

The first optical filter 25 receives light received by each element of the optical sampling array 20, transmits part of the input light, and inputs the light to the photoelectric conversion element 21.
The first optical filter 25 transmits light in a band in which the first signal light beam 3 and the first local light beam 4 are set, and the second signal light beam 8 and the second local light beam. 9 blocks light in the set band. The photoelectric conversion element 21 and the first optical filter 25 are collectively referred to as first demodulation means.

The second optical filters 56a and 56b receive the light received by the phase monitoring fibers 50a and 50b of the optical sampling array 20, and transmit a part of the input light to input to the photoelectric conversion elements 51a and 51b. .
The second optical filters 56a and 56b block the light in the band in which the first signal light beam 3 and the first local light beam 4 are set, and the second signal light beam 8 and the second local light beam 4b. The light beam 9 transmits light in the set band. The photoelectric conversion elements 51a and 51b and the second optical filters 56a and 56b are collectively referred to as second demodulation means.

  The light received by each fiber of the optical sampling array 20 excluding the two phase monitoring fibers 50a and 50b passes only the first signal light and the first local light through the first optical filter 25, and is photoelectrically converted. The element 21 demodulates the first signal light and the first local light into the first microwave. This first microwave is fed to the antenna element of the array antenna 23 and radiated to the space.

  On the other hand, the light received by the two phase monitoring fibers 50a and 50b passes only the second signal light and the second local light through the second optical filters 56a and 56b, and passes through the photoelectric conversion elements 51a and 51b. Demodulate the second signal light and the second local light into the second microwave. The demodulated two second microwaves are input to the phase comparator 53 as in the first embodiment.

  Thus, the light received by the two fibers designated for phase monitoring in the optical sampling array 20 is converted into the second microwave so that the phase difference between the two converted second microwaves becomes constant. In addition, since phase modulation is performed in the direction opposite to the phase fluctuation direction of the first local light beam 4 and the second local light beam 9, the beam is controlled in a desired direction even if the optical system fluctuates due to temperature, vibration, or the like. be able to.

  Moreover, since the frequency bands of the first microwave and the second microwave are the same, the frequency dependence of the microwave component can be eliminated.

Embodiment 3 FIG.
FIG. 3 is a diagram showing a configuration of an optically controlled foods array antenna device according to Embodiment 3 of the present invention.
The optically controlled phased array antenna apparatus according to the third embodiment of the present invention can vary the inclination of the combined local light beam 18 incident on the optically controlled phased array antenna apparatus and the second beam combiner 16 according to the first embodiment. The mirror device 14 to be added is added and the P-SLM 12 is omitted, and the other parts are the same. Therefore, the same parts are denoted by the same reference numerals and the description thereof is omitted.

  The combined local light beam 18 is incident on the mirror device 14 so that the difference in wavefront inclination between the second signal light beam 8 and the second local light beam 9 calculated by the calculation device 55 converges to a predetermined value. It is controlled by the spatial phase controller 13.

Thus, the light received by the two fibers designated for phase monitoring in the optical sampling array 20 is converted into the second microwave so that the phase difference between the two converted second microwaves becomes constant. In addition, since the inclinations of the first local light beam 4 and the second local light beam 9 are adjusted, the beam can be controlled in a desired direction even if the optical system fluctuates due to temperature, vibration or the like.
Further, since the mirror device 14 controls the inclination of the wavefronts of the first local light beam 4 and the second local light beam 9, it is easy to increase the dynamic range of the inclination amount.

Embodiment 4 FIG.
FIG. 4 is a diagram showing a configuration of an optically controlled foods array antenna apparatus according to Embodiment 4 of the present invention.
In the optical control type phased array antenna device according to the first embodiment of the present invention, the local light beam is adjusted. However, in the optical control type phased array antenna device according to the fourth embodiment of the present invention, the signal light beam is adjusted. .
For this reason, the spatial light intensity modulation device 10 is controlled so that the difference between the slopes of the wavefronts of the second signal light beam 8 and the second local light beam 9 calculated by the calculation device 55 converges to a predetermined value. The intensity distribution of the first signal light beam 3 and the second signal light beam 8 is intensity-modulated.

  Thus, the light received by the two fibers designated for phase monitoring in the optical sampling array 20 is converted into the second microwave, and the phase difference between the two converted second microwaves becomes a predetermined value. Since the inclination of the wave front of the first signal light beam 3 and the second signal light beam 8 is adjusted so as to converge, the beam can be controlled in a desired direction even if the optical system fluctuates due to temperature, vibration, or the like. it can.

  In the fourth embodiment described above, the desired microwave is separated from the microwave demodulated by the photoelectric conversion element 21 by the microwave filter. However, as in the second embodiment, the desired light is emitted from the optical filter. You may demodulate to a microwave, after isolate | separating.

Embodiment 5 FIG.
FIG. 5 is a diagram showing a configuration of an optically controlled foods array antenna apparatus according to Embodiment 5 of the present invention.
In the optical control type phased array antenna device according to the first to fourth embodiments described above, two fibers are selected as the phase monitoring fibers 50a and 50b from the fibers of the optical sampling array 20, and the second signal light beam 8 and the second signal light beam 8 are used. The difference in wavefront inclination between the two local light beams 9 is calculated, and the calculated wavefront inclination is an inclination on one line of the wavefront.

On the other hand, the optically controlled food array antenna apparatus according to the fifth embodiment of the present invention uses four fibers selected from the fibers of the optical sampling array 20 as phase monitoring fibers 50a, 50b, 60a, 60b. ing. The fibers of the optical sampling array 20 are arranged on a plane.
The phase monitoring fibers 50a and 50b select fibers located on the upper and lower sides on the vertical line passing through the center of the optical sampling array 20, and the phase monitoring fibers 60a and 60b are on the horizontal line passing through the center of the optical sampling array 20. Select the fibers located on both the left and right sides.

  The optically controlled food array antenna apparatus according to the fifth embodiment of the present invention includes the first micro-signal generated in the photoelectric conversion elements 51a and 51b and the photoelectric conversion elements 51a and 51b connected to the phase monitoring fibers 50a and 50b. Of the microwave and the second microwave, the positions of the two second microwaves that have passed through the second microwave filters 52a and 52b that pass only the second microwave and the second microwave filters 52a and 52b. A vertical phase comparator 53b that outputs a DC electric signal corresponding to the phase difference is provided.

  Further, the optical control type food array antenna apparatus according to the fifth embodiment of the present invention is the first generated in the photoelectric conversion elements 61a and 61b and the photoelectric conversion elements 61a and 61b connected to the phase monitoring fibers 60a and 60b. Among the second microwave and the second microwave, the second microwave filters 62a and 62b that transmit only the second microwave and the two second microwaves that transmit through the second microwave filters 62a and 62b The horizontal phase comparison device 63 that outputs a DC electric signal corresponding to the phase difference is provided.

  Further, in the optical control type foos array antenna apparatus according to Embodiment 5 of the present invention, the wave fronts of the second signal light beam 8 and the second local light beam 9 from the DC electric signal of the vertical phase comparator 53b. An arithmetic unit that calculates the difference in inclination in the vertical direction and the difference in inclination in the horizontal direction of the wavefronts of the second signal light beam 8 and the second local light beam 9 from the DC electric signal of the horizontal phase comparator 63. 55.

  In this way, light received by a total of four fibers, that is, two fibers separated in the vertical direction of the optical sampling array 20 and two fibers separated in the horizontal direction, is converted into a second microwave, and each of the two converted fibers is converted. Since the slopes of the wavefronts of the first local light beam 4 and the second local light beam 9 are adjusted both in the vertical direction and in the horizontal direction so that the phase difference of the second microwave converges to a predetermined value, 2 The present invention can also be applied to a two-dimensional array antenna in which antenna elements are arranged in a dimension.

In Embodiment 5 described above, the desired microwave is separated by the microwave filter from the microwave demodulated by the photoelectric conversion element, but the desired light is separated by the optical filter as in Embodiment 2 described above. Then, it may be demodulated into microwaves.
In the above-described fifth embodiment, the spatial phase distribution of the combined local light beam is phase-modulated by the spatial light phase modulator. The angle of incidence on the beam combiner may be varied.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the optical control type phased array antenna apparatus by Embodiment 1 which concerns on this invention. It is a block diagram of the optical control type phased array antenna apparatus by Embodiment 2 which concerns on this invention. It is a block diagram of the optical control type phased array antenna apparatus by Embodiment 3 which concerns on this invention. It is a block diagram of the optical control type phased array antenna apparatus by Embodiment 4 which concerns on this invention. It is a block diagram of the optical control type phased array antenna apparatus by Embodiment 5 which concerns on this invention.

Explanation of symbols

  1, 1B 1st microwave-light output device, 2, 7 microwave input terminal, 3 1st signal light beam, 4 1st local light beam, 6, 6B 2nd microwave-light output device, 8 Second signal light beam, 9 Second local light beam, 10 Spatial light intensity modulator (A-SLM), 11 Spatial light intensity modulator driver, 12 Spatial light phase modulator (P-SLM), 13 Spatial phase controller, 14 mirror device, 15 Fourier transform lens, 16 second beam synthesizer, 17 first beam synthesizer, 18 synthesized local light beam, 19 synthesized light beam, 20 optical sampling array, 21 photoelectric conversion element , 22 1st microwave filter, 23 array antenna, 25 1st optical filter, 50a, 50b, 60a, 60b Phase monitor fiber, 51a, 5 1b, 61a, 61b photoelectric conversion element, 52a, 52b, 62a, 62b second microwave filter, 53 phase comparator, 53a vertical phase comparator, 55 arithmetic unit, 56a, 56b second optical filter, 63 horizontal phase Comparison device.

Claims (8)

While emitting a first signal light beam, and the first signal light beam first local light beam said first signal light beam to detuning by the frequency of the first microwave from being emitting space A first microwave-light output device that emits into a different space;
A second signal light beam is emitted to a space different from the space from which the first signal light beam is emitted, and a second microwave having a frequency different from that of the first microwave is emitted from the second signal light beam. A second microwave-light output device that emits a second local light beam that is detuned by a frequency different from the space from which the second signal light beam is emitted;
A spatial light intensity modulator that modulates the spatial intensity distribution of the first signal light beam and the second signal light beam;
A Fourier transform lens that spatially Fourier transforms the first signal light beam and the second signal light beam modulated by the spatial light intensity modulator;
A first beam combiner that spatially combines the first local light beam and the second local light beam into a combined local light beam;
A second beam combiner that spatially combines the Fourier-transformed first signal light beam and second signal light beam with the combined local light beam to form a combined light beam;
An optical sampling array composed of a plurality of fibers for spatially sampling the combined light beam;
A plurality of first demodulation means for demodulating the first microwave from each output of the fiber;
An array antenna that radiates the first microwave demodulated by the plurality of first demodulation means into space;
In the optically controlled phased array antenna device comprising:
Two phase monitoring fibers for sampling the combined light beam at two positions spaced apart on a straight line;
Two second demodulating means for demodulating the second microwave from each output of the phase monitoring fiber;
A phase comparison device that outputs a phase difference between the second microwaves demodulated by the two second demodulation means as a DC electric signal;
An arithmetic unit that calculates a difference in inclination on one line of the wavefront of the second signal light beam and the second local light beam from the DC electric signal of the phase comparator;
Based on the calculation result of the calculation device, the first signal light so that a difference in inclination on one line of the wavefront between the second signal light beam and the second local light beam converges to a predetermined value. Wavefront correction means for controlling the beam and the second signal light beam or the combined local light beam;
An optically controlled phased array antenna device comprising: While emitting a first signal light beam, and the first signal light beam first local light beam said first signal light beam to detuning by the frequency of the first microwave from being emitting space A first microwave-light output device that emits into a different space;
The second signal light beam is emitted to a space different from the wavelength band of the first signal light beam and different from the space from which the first signal light beam was emitted, and the second signal light beam is A second microwave-light output device that emits a second local light beam detuned by the frequency of the microwave to a space different from the space from which the second signal light beam was emitted;
A spatial light intensity modulator that modulates the spatial intensity distribution of the first signal light beam and the second signal light beam;
A Fourier transform lens that spatially Fourier transforms the first signal light beam and the second signal light beam modulated by the spatial light intensity modulator;
A first beam combiner that spatially combines the first local light beam and the second local light beam into a combined local light beam;
A second beam combiner that spatially combines the Fourier-transformed first signal light beam and second signal light beam with the combined local light beam to form a combined light beam;
An optical sampling array composed of a plurality of fibers for spatially sampling the combined light beam;
A plurality of first demodulation means for demodulating the first microwave from each output of the fiber;
An array antenna that radiates the first microwave demodulated by the plurality of first demodulation means into space;
In the optically controlled phased array antenna device comprising:
Two phase monitoring fibers for sampling the combined light beam at two positions spaced apart on a straight line;
Two second demodulating means for demodulating the second microwave from each output of the phase monitoring fiber;
A phase comparison device that outputs a phase difference between the second microwaves demodulated by the two second demodulation means as a DC electric signal;
An arithmetic unit that calculates a difference in inclination on one line of the wavefront of the second signal light beam and the second local light beam from the DC electric signal of the phase comparator;
Based on the calculation result of the calculation device, the first signal light so that a difference in inclination on one line of the wavefront between the second signal light beam and the second local light beam converges to a predetermined value. Wavefront correction means for controlling the beam and the second signal light beam or the combined local light beam;
An optically controlled phased array antenna device comprising: The first demodulating means includes a photoelectric conversion element that heterodyne-detects the output from the fiber and demodulates the output to the first microwave and the second microwave, and a first demodulated by the photoelectric conversion element. A first microwave filter that transmits only microwaves;
The second demodulating means performs a heterodyne detection on the output from the phase monitoring fiber and demodulates the output into the first microwave and the second microwave, and is demodulated by the photoelectric conversion element. A second microwave filter that transmits only the second microwave;
The optically controlled phased array antenna device according to claim 1, comprising: The frequency of the first microwave and the second microwave are the same;
The first demodulating means includes: a first optical filter that transmits only the first signal light and the first local light from the output of the fiber; a first signal light that transmits the first optical filter; A photoelectric conversion element for heterodyne detection of the first local light and demodulating the first microwave;
The second demodulating means includes a second optical filter that transmits only the second signal light and the second local light from the output of the phase monitoring fiber, and a second optical filter that transmits the second optical filter. A photoelectric conversion element for heterodyne detection of signal light and second local light to demodulate the second microwave;
The optically controlled phased array antenna device according to claim 2, comprising: Two other phase monitoring fibers for sampling the combined light beam at two positions spaced apart on another straight line intersecting the straight line;
Two other second demodulation means for demodulating the second microwave from each output of the other phase monitoring fiber;
Another phase comparison device that outputs the phase difference of the second microwave demodulated by the two other second demodulation means as a DC electric signal;
With
The arithmetic device calculates a difference in inclination on the other line of the wave front of the second signal light beam and the second local light beam from the DC electric signal of the other phase comparison device,
The wavefront correction unit is configured so that a difference in inclination between two wavefronts of the second signal light beam and the second local light beam converges to a predetermined value based on a calculation result of the calculation device. The light control type phased array according to any one of claims 1 to 4, wherein the first signal light beam and the second signal light beam or the combined local light beam are controlled. Antenna device. The wavefront correction means converges a difference in inclination on one or two lines of the wavefronts of the second signal light beam and the second local light beam to a predetermined value based on a calculation result of the calculation device. The optically controlled phased array antenna according to claim 1, further comprising a spatial phase modulator that performs phase modulation on a spatial phase distribution of the combined local light beam. apparatus. The wavefront correction means converges a difference in inclination on one or two lines of the wavefronts of the second signal light beam and the second local light beam to a predetermined value based on a calculation result of the calculation device. The light control according to claim 1, further comprising a mirror device that varies an incident angle of the combined local light beam to the second beam combiner. Type phased array antenna device. The wavefront correction means converges a difference in inclination on one or two lines of the wavefronts of the second signal light beam and the second local light beam to a predetermined value based on a calculation result of the calculation device. The light control type phased array antenna device according to claim 1, further comprising a driver that controls the spatial light intensity modulator.

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