Wind observation device, wind observation method, and wind observation system

Abstract

A wind observation device (3) is configured in a manner comprising: a reception signal acquisition unit (31) that acquires, from a conical scan type sensor (1) that radiates laser beams repeatedly toward a wind observation region and receives scattered beams of the laser beams scattered due to aerosol present in the wind observation region, reception signals of the scattered beams; and a signal integration unit (32) that shifts the frequencies of the reception signals acquired by the reception signal acquisition unit (31), by using a frequency shift amount corresponding to each of a plurality of different wind vectors, and integrates the spectra of the plurality of frequency-shifted reception signals for the wind vectors. Further, the wind observation device (3) comprises a wind vector selection unit (33) for selecting a wind vector corresponding to the wind vector in the wind observation region from among the plurality of wind vectors on the basis of the spectrum of the reception signals resulting from integration by the signal integration unit (32) for the wind vectors.

Description

Wind observation device, wind observation method, and wind observation system

[0001] The present disclosure relates to a wind observation device, a wind observation method, and a wind observation system.

[0002] There is a wind observation device that observes wind vectors in a wind observation area. For example, Non-Patent Document 1 discloses a wind observation device that acquires multiple received signals from a conical scan sensor and calculates wind vectors in the wind observation area based on the multiple received signals. The conical scan method switches the direction of laser light irradiation so that the irradiation position of the laser light on the wind observation area changes over time. The irradiation position of the laser light changes to surround the center of the wind observation area. A conical scan sensor repeatedly emits laser light toward the wind observation area and receives scattered light from each laser light scattered by aerosols present in the wind observation area. The sensor then outputs a received signal of each scattered light to the wind observation device.

[0003] Browning KA, Wexler R. “The Determination of Kinematic Properties of a Wind Field Using Doppler Radar”, Journal of Applied Meteorology, Vol.7, No.1, pp.105-113, 1968.

[0004] The received signal of light scattered by aerosols generally has a low signal-to-noise ratio (hereinafter referred to as "SNR"). The wind observation device disclosed in Non-Patent Document 1 has a problem in that the calculation accuracy of the wind vector may deteriorate if the SNR of each received signal is low. If the irradiation positions of multiple laser beams are the same, the SNR may be improved by integrating the multiple received signals. However, with the conical scanning method, the irradiation positions of multiple laser beams relative to the wind observation area are different from each other, and therefore the Doppler frequencies of the multiple scattered lights may differ from each other. Therefore, integrating the received signals of multiple scattered lights does not necessarily improve the SNR.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to obtain a wind observation device that can increase the SNR of the received signal more than the wind observation device disclosed in Non-Patent Document 1, thereby preventing deterioration in the accuracy of wind vector calculation.

[0006] The wind observation device according to the present disclosure includes a received signal acquisition unit that acquires received signals of each scattered light from a conical scan sensor that repeatedly emits laser light toward a wind observation area and receives scattered light of each laser light scattered by aerosols present in the wind observation area, and a signal integration unit that shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each of a plurality of different wind vectors and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector. The wind observation device also includes a wind vector selection unit that selects a wind vector corresponding to the wind vector of the wind observation area from among the plurality of wind vectors based on the spectrum of the received signal integrated by the signal integration unit for each wind vector.

[0007] According to the present disclosure, the SNR of the received signal can be increased compared to the wind observation device disclosed in Non-Patent Document 1, and deterioration of the calculation accuracy of the wind vector can be prevented.

[0008] 5A is an explanatory diagram showing the irradiation direction of the transmitted light when the sensor 1 and the wind observation area are respectively viewed from the side, and FIG. 5B is an explanatory diagram showing the irradiation direction of the transmitted light when the sensor 1 and the wind observation area are respectively viewed from above. An explanatory diagram showing the wind vector at the irradiation position of the transmitted light. An explanatory diagram showing the spectrum of the received data S(AZ(n), Rb) whose frequency has not been shifted by the first shift processing unit 32a. An explanatory diagram showing the spectrum of the received data S(AZ(n), Rb) whose frequency has been shifted by the first shift processing unit 32a. An explanatory diagram showing the spectrum of the received data S(AZ(n), Rb) whose frequency has been shifted by the first shift processing unit 32a. ｒｅｖFIG. 10 is an explanatory diagram showing the spectrum SPC(H(i), W(j), θ(k), n, Rb) of (H(i), W(j), θ(k), n, Rb). FIG. 11 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 2. FIG. 12 is a hardware configuration diagram showing the hardware of a wind observation device 3 according to embodiment 2. FIG. 13 is a hardware configuration diagram showing the hardware of a wind observation device 3 according to embodiment 3. FIG. 14 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 4. FIG. 15 is a hardware configuration diagram showing the hardware of a wind observation device 3 according to embodiment 4.

[0009] In order to explain the present disclosure in more detail, embodiments of the present disclosure will be described below with reference to the accompanying drawings.

[0010] Embodiment 1. Fig. 1 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 1. Fig. 2 is a hardware configuration diagram showing the hardware of the wind observation device 3 according to embodiment 1. The wind observation system shown in Fig. 1 comprises a sensor 1, an A / D converter (Analog to Digital converter) 2, and the wind observation device 3.

[0011] The sensor 1 includes an optical oscillator 11, a coupler 12, an optical modulator 13, an optical amplifier 14, an optical circulator 15, an optical antenna 16, a scanner 17, a scanner driver 18, a multiplexing coupler 19, and an optical receiver 20. The sensor 1 is a conical scan type sensor. The sensor 1 repeatedly emits, as laser light, for example, pulsed light toward a wind observation area. The sensor 1 receives scattered light of each pulsed light scattered by aerosols present in the wind observation area. The sensor 1 then outputs a received signal of each scattered light to a wind observation device 3 via an A / D converter 2. In the wind observation system shown in FIG. 1 , the sensor 1 emits, as laser light, pulsed light toward the wind observation area. However, this is merely an example, and the sensor 1 may also emit, as laser light, for example, continuous light toward the wind observation area.

[0012] The optical oscillator 11 is realized by, for example, a semiconductor laser or a solid-state laser. The optical oscillator 11 oscillates laser light such as pulsed light and outputs the laser light to the coupler 12. The coupler 12 is realized by, for example, a fused fiber coupler or a filter-type coupler using a dielectric multilayer filter. The coupler 12 splits the laser light output from the optical oscillator 11 into transmission light and local light. The coupler 12 outputs the transmission light to the optical modulator 13 and outputs the local light to the multiplexing coupler 19.

[0013] The optical modulator 13 is realized by, for example, an AO frequency shifter (Acoustic Optical Frequency Shifter) or an optical phase modulator. The optical modulator 13 shifts the frequency of the transmission light by performing phase modulation or frequency modulation on the transmission light output from the coupler 12. Furthermore, the optical modulator 13 performs intensity modulation on the frequency-shifted transmission light at the timing when a trigger signal is received from the wind observation device 3. The optical modulator 13 outputs the intensity-modulated transmission light to the optical amplifier 14.

[0014] The optical amplifier 14 amplifies the transmission light output from the optical modulator 13 and outputs the amplified transmission light to the optical circulator 15. The optical circulator 15 is realized by, for example, a wave plate and a beam splitter. The optical circulator 15 outputs the transmission light output from the optical amplifier 14 to the optical antenna 16 and outputs the scattered light output from the optical antenna 16 to the multiplexing coupler 19.

[0015] The optical antenna 16 is realized by, for example, an optical telescope or a camera lens. The optical antenna 16 emits the transmitted light output from the optical circulator 15. The optical antenna 16 receives scattered light of the transmitted light scattered by aerosols present in the wind observation area. The optical antenna 16 outputs the scattered light to the optical circulator 15.

[0016] The scanner 17 is realized by, for example, a motor scanner or a wedge scanner that controls the optical antenna 16 along two axes. The scanner 17 controls the direction of the transmitted light emitted from the optical antenna 16 in accordance with a control signal output from the scanner driver 18 so that the irradiation position of the transmitted light relative to the wind observation area changes over time. The irradiation position of the transmitted light changes to surround the center of the wind observation area. The scanner driver 18 acquires angle information (AZ, φ) related to the irradiation direction of the transmitted light from the wind observation device 3. AZ is the azimuth angle, and φ is the zenith angle (see FIG. 5 ). The scanner driver 18 outputs a control signal to the scanner 17 to control the scanner 17 so that the irradiation direction of the transmitted light emitted from the optical antenna 16 is the irradiation direction indicated by the angle information (AZ, φ).

[0017] The multiplexing coupler 19 is realized by, for example, a fused fiber coupler or a filter-type coupler using a dielectric multilayer filter. The multiplexing coupler 19 multiplexes the local light output from the coupler 12 and the scattered light output from the optical circulator 15, and outputs the multiplexed light of the local light and the scattered light to the optical receiver 20. The optical receiver 20 is realized by, for example, a balanced receiver. The optical receiver 20 performs heterodyne detection on the multiplexed light output from the multiplexing coupler 19. The optical receiver 20 converts an optical signal indicating the detection result of the heterodyne detection into an electrical signal, and outputs the electrical signal to the A / D converter 2.

[0018] The A / D converter 2 is realized by, for example, a double integral type A / D converter, a successive approximation type A / D converter, or a parallel comparison type A / D converter. The A / D converter 2 converts an analog signal, which is an electrical signal output from the optical receiver 20, into a digital signal. The A / D converter 2 outputs the received data, which is a digital signal, to the wind observation device 3. In the wind observation system shown in FIG. 1 , the A / D converter 2 is provided separately from each of the sensor 1 and the wind observation device 3. However, this is merely an example, and the A / D converter 2 may be built into either the sensor 1 or the wind observation device 3.

[0019] The wind observation device 3 includes a received signal acquisition unit 31, a signal integrator 32, and a wind vector selector 33. The received signal acquisition unit 31 is realized, for example, by a received signal acquisition circuit 41 shown in FIG. 2. The received signal acquisition unit 31 acquires received data output from the A / D converter 2 as received signals of scattered light of each laser beam scattered by aerosols present in the wind observation area. The received signal acquisition unit 31 outputs the received data to the signal integrator 32.

[0020] The signal integrator 32 is realized by, for example, the signal integrator circuit 42 shown in FIG. 2 . The signal integrator 32 includes a first shift processor 32 a and a first signal integration processor 32 b. The signal integrator 32 shifts the frequency of each received signal acquired by the received signal acquirer 31 using a frequency shift amount corresponding to each of a plurality of different wind vectors. The signal integrator 32 integrates the spectrum of the plurality of frequency-shifted received signals for each wind vector. Each of the plurality of wind vectors includes three elements: a horizontal wind speed value H, a vertical wind speed value W, and a wind direction θ. Each wind vector differs from the other wind vectors in one or more of the three elements.

[0021] The first shift processing unit 32a acquires received data as received signals of each scattered light from the received signal acquisition unit 31. The first shift processing unit 32a shifts the frequency of each received data by using a frequency shift amount corresponding to each of the multiple wind vectors. The frequency shift by the first shift processing unit 32a is a shift in the time domain. The first shift processing unit 32a outputs the frequency-shifted received data for each wind vector to the first signal integration processing unit 32b.

[0022] The first signal integration processing unit 32b acquires each of the frequency-shifted reception data for each wind vector from the first shift processing unit 32a. The first signal integration processing unit 32b calculates the spectrum of each of the frequency-shifted reception data for each wind vector. The first signal integration processing unit 32b integrates the spectra of the multiple reception data for each wind vector. The first signal integration processing unit 32b outputs the spectrum of the integrated reception data for each wind vector to the wind vector selection unit 33.

[0023] The wind vector selection unit 33 is realized, for example, by the wind vector selection circuit 43 shown in FIG. 2 . The wind vector selection unit 33 acquires the spectrum of the integrated received data for each wind vector from the signal integrator 32. The wind vector selection unit 33 selects, from among the multiple wind vectors, a wind vector corresponding to the wind vector of the wind observation area based on the spectrum of the integrated received data for each wind vector. Specifically, the wind vector selection unit 33 identifies the peak value contained in the spectrum of each wind vector after integration by the signal integrator 32. The wind vector selection unit 33 then compares the peak values ​​for the multiple wind vectors with each other. The wind vector selection unit 33 then selects, from among the multiple wind vectors, a wind vector corresponding to the wind vector of the wind observation area based on the comparison of the peak values. The wind vector selection unit 33 outputs the wind vector of the wind observation area to, for example, a display device (not shown).

[0024] In Fig. 1, it is assumed that each of the components of the wind observation device 3, the received signal acquisition unit 31, the signal integration unit 32, and the wind vector selection unit 33, is realized by dedicated hardware as shown in Fig. 2. That is, it is assumed that the wind observation device 3 is realized by a received signal acquisition circuit 41, a signal integration circuit 42, and a wind vector selection circuit 43. Each of the received signal acquisition circuit 41, the signal integration circuit 42, and the wind vector selection circuit 43 is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination of these.

[0025] The components of the wind observation device 3 are not limited to those realized by dedicated hardware, and the wind observation device 3 may be realized by software, firmware, or a combination of software and firmware. Software or firmware is stored as a program in the memory of a computer. A computer refers to hardware that executes a program, and includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, a processor, or a DSP (Digital Signal Processor).

[0026] 3 is a hardware configuration diagram of a computer when the wind observation device 3 is realized by software, firmware, etc. When the wind observation device 3 is realized by software, firmware, etc., a program for causing a computer to execute the respective processing procedures of the received signal acquisition unit 31, the signal integration unit 32, and the wind vector selection unit 33 is stored in a memory 51. Then, a processor 52 of the computer executes the program stored in the memory 51.

[0027] 2 shows an example in which each of the components of the wind observation device 3 is realized by dedicated hardware, while Fig. 3 shows an example in which the wind observation device 3 is realized by software, firmware, etc. However, this is only one example, and some of the components in the wind observation device 3 may be realized by dedicated hardware, and the remaining components may be realized by software, firmware, etc.

[0028] Next, the operation of the wind observation system shown in Fig. 1 will be described. Fig. 4 is a flowchart showing a wind observation method, which is the processing procedure of the wind observation device 3. The optical oscillator 11 oscillates laser light such as pulsed light and outputs the laser light to the coupler 12. The coupler 12 acquires the laser light from the optical oscillator 11. The coupler 12 splits the laser light into transmission light and local light. The coupler 12 outputs the transmission light to the optical modulator 13 and outputs the local light to the multiplexing coupler 19.

[0029] The optical modulator 13 receives the transmission light from the coupler 12. The optical modulator 13 performs phase modulation or frequency modulation on the transmission light to shift the frequency of the transmission light. The optical modulator 13 also performs intensity modulation on the frequency-shifted transmission light at the timing when a trigger signal is received from the wind observation device 3. The optical modulator 13 then outputs the intensity-modulated transmission light to the optical amplifier 14. The optical amplifier 14 amplifies the transmission light output from the optical modulator 13 and outputs the amplified transmission light to the optical circulator 15.

[0030] When the optical circulator 15 receives the transmission light from the optical amplifier 14, it outputs the transmission light to the optical antenna 16. The optical antenna 16 radiates the transmission light output from the optical circulator 15.

[0031] The scanning speed and scanning angle range of the scanner 17 are set in advance in the received signal acquisition unit 31 of the wind observation device 3. The scanning speed is set by the user within a speed range in which the scanner 17 can scan. The scanning angle range is set by the user within an angle range in which the scanner 17 can scan. For example, 10 [deg / sec] is set as the scanning speed, and 0 to 359 [deg] is set as the scanning angle range. The received signal acquisition unit 31 outputs angle information (AZ, φ) relating to the irradiation direction of the transmitted light to the scanner driver 18. The angle information (AZ, φ) is determined by the scanning speed and the scanning angle range. The scanner driver 18 outputs a control signal to the scanner 17 to control the scanner 17 so that the irradiation direction of the transmitted light radiated from the optical antenna 16 is the irradiation direction indicated by the angle information (AZ, φ). As shown in Figure 5, the scanner 17 controls the direction of irradiation of the transmitted light from the optical antenna 16 in accordance with the control signal output from the scanner driver 18 so that the irradiation position of the transmitted light on the wind observation area surrounds the center of the wind observation area.

[0032] FIG. 5 is an explanatory diagram showing the irradiation direction of the transmitted light from the optical antenna 16. FIG. 5A is an explanatory diagram showing the irradiation direction of the transmitted light when the sensor 1 and the wind observation area are viewed from the side. FIG. 5B is an explanatory diagram showing the irradiation direction of the transmitted light when the sensor 1 and the wind observation area are viewed from above. In FIG. 5, AZ is the azimuth angle, φ is the zenith angle, and the irradiation direction of the transmitted light is determined by the azimuth angle AZ and the zenith angle φ. θ is the wind direction in the wind observation area. The wind observation area shown in FIG. 5 indicates the wind observation area in one of range bins Rb (Rb = 1, 2, ..., RB) out of the R B range bins described below. FIG. 6 is an explanatory diagram showing the wind vector at the irradiation position of the transmitted light. In FIG. 6, the horizontal axis represents the azimuth angle AZ, and the vertical axis represents the wind vector at the irradiation position of the transmitted light. The wind vector includes three elements: the horizontal wind speed value H, the vertical wind speed value W, and the wind direction θ. The wind speed value of the horizontal wind H is the horizontal component of the wind in the wind observation area, and the wind speed value of the vertical wind W is the vertical component of the wind in the wind observation area. Since the irradiation direction of the transmitted light is controlled so that the irradiation positions of the transmitted light with respect to the wind observation area surround the center of the wind observation area, the multiple irradiation positions are generally represented by a cosine function waveform.

[0033] The optical antenna 16 receives scattered light of the transmitted light scattered by aerosols present in the wind observation area. Specifically, the optical antenna 16 receives scattered light of the transmitted light scattered by aerosols at each irradiation position. The optical antenna 16 outputs each scattered light to the optical circulator 15.

[0034] Upon receiving the respective scattered lights from the optical antenna 16, the optical circulator 15 outputs the respective scattered lights to the multiplexing coupler 19. The multiplexing coupler 19 multiplexes the local light output from the coupler 12 and the respective scattered lights output from the optical circulator 15. The multiplexing coupler 19 outputs the multiplexed light of the local light and the respective scattered lights to the optical receiver 20.

[0035] The optical receiver 20 receives each multiplexed light from the multiplexing coupler 19. The optical receiver 20 heterodyne detects each multiplexed light and converts an optical signal indicating the result of the heterodyne detection into an electrical signal. The optical receiver 20 outputs each electrical signal to the A / D converter 2. The A / D converter 2 receives each electrical signal from the optical receiver 20. The A / D converter 2 converts each analog electrical signal into received data S(AZ(n)), which is a digital signal. n is a variable indicating the order of the transmitted light emitted from the sensor 1, and n = 1, ..., N. AZ(n) indicates the azimuth angle related to the emission direction of the nth transmitted light. N is an integer equal to or greater than 1. The wind observation system shown in FIG. 1 illustrates an example in which the zenith angle φ is fixed. Therefore, the received data S(AZ(n)) omits the variable for the zenith angle φ. When the zenith angle φ changes, the received data is expressed as, for example, S(AZ(n), φ(n)). The A / D converter 2 outputs each received data S(AZ(n)) to the wind observation device 3.

[0036] The received signal acquisition unit 31 acquires each piece of received data S(AZ(n)) from the A / D converter 2 (step ST1 in FIG. 4 ). The received signal acquisition unit 31 outputs each piece of received data S(AZ(n)) to the signal accumulator 32.

[0037] The first shift processing unit 32a of the signal integrating unit 32 acquires each piece of received data S(AZ(n)) from the received signal acquiring unit 31. A distance resolution is set in advance in the first shift processing unit 32a. The first shift processing unit 32a divides each piece of received data S(AZ(n)) into time intervals corresponding to the distance resolution. If the distance resolution is, for example, 30 [m], the time interval corresponding to the distance resolution is 200 [ns] (= 2 × R ｒｅｓ / c), and the received data S(AZ(n)) is separated at intervals of 200 [ns]. c is the speed of light, R ｒｅｓis the distance resolution. The first shift processing unit 32a stores the received data S(AZ(n), Rb) divided by a time width corresponding to the distance resolution. Rb is a variable indicating the range bin, and Rb=1, 2, ..., RB. RB is the total number of range bins.

[0038] The internal memory of the first shift processing unit 32a stores (I×J×K) wind vectors (H(i), W(j), θ(k)). Each of I, J, and K is an integer equal to or greater than 1. i=1,...,I, j=1,...,J, and k=1,...,K. H(i) is the minimum value H of the wind speed value of the horizontal wind H. ｍｉｎ The maximum value of the horizontal wind speed H ｍａｘ The wind speed value H(i) of the horizontal wind H is, for example, 0 (=minimum value H ｍｉｎ ) [m / s] to 10 (= maximum value H ｍａｘ ) [m / s] in increments of 1 [m / s] can be used. W(j) is the minimum value W of the vertical wind speed W. ｍｉｎ The maximum wind speed value of vertical wind W ｍａｘ The wind speed value W(j) of the vertical wind W is, for example, -5 (=minimum value W ｍｉｎ ) [m / s] to 5 (= maximum value W ｍａｘ ) [m / s] in increments of 1 [m / s] can be used. ｍｉｎ From θ ｍａｘ The wind direction θ(k) is any one of K wind directions from 0 (=θ ｍｉｎ ) [deg] ~ 359 (=θ ｍａｘ ) [deg] in increments of 1 [deg] can be used.

[0039] The first shift processing unit 32a calculates a frequency shift amount f corresponding to the wind vector (H(i), W(j), θ(k)) (i=1, . . . , I; j=1, . . . , J; k=1, . . . , K) for each range bin Rb (Rb=1, 2, . . . , RB) as shown in the following equation (1). ｄ Calculate (H(i), W(j), θ(k), AZ(n), Rb).

[0040] In equation (1), λ is the wavelength of the transmitted light.

[0041] The first shift processing unit 32a calculates the frequency shift amount f for each range bin Rb (Rb=1, 2, . . . , RB) as shown in the following equation (2). ｄ Using (H(i), W(j), θ(k), AZ(n), Rb) (i=1,...,I; j=1,...,J; k=1,...,K), the frequency of the received data S(AZ(n), Rb) is shifted in the time domain (step ST2 in FIG. 4). The first shift processing unit 32a shifts the frequency of the received data S(AZ(n), Rb) in the time domain for each range bin Rb (Rb=1,2,...,RB). ｒｅｖ (H(i), W(j), θ(k), n, Rb) (i=1,...,I; j=1,...,J; k=1,...,K) is output to the first signal integration processing unit 32b.

[0042]

[0043] The first signal integration processing unit 32b receives the frequency-shifted reception data S for each range bin Rb (Rb=1, 2, . . . , RB) from the first shift processing unit 32a. ｒｅｖ (H(i), W(j), θ(k), n, Rb) (i=1,...,I; j=1,...,J; k=1,...,K). The first signal integration processing unit 32b obtains the frequency-shifted received data S ｒｅｖ By performing FFT (Fast Fourier Transform) on (H(i), W(j), θ(k), n, Rb), the frequency-shifted received data S ｒｅｖ The spectrum SPC(H(i), W(j), θ(k), n, Rb) of (H(i), W(j), θ(k), n, Rb) is calculated (step ST3 in FIG. 4).

[0044]

[0045] FIG. 7 is an explanatory diagram showing the spectrum of the received data S(AZ(n), Rb) whose frequency has not been shifted by the first shift processing unit 32a. The FFT bins on the horizontal axis of FIG. 7 correspond to range bins. When the sensor 1 is a conical scan type sensor, the range bin corresponding to the largest spectral component among the multiple spectral components contained in the received data S(AZ(n), Rb) corresponding to each azimuth angle AZ is roughly expressed by a waveform of a cosine function. FIG. 8 is an explanatory diagram showing the spectrum of the received data S(AZ(n), Rb) whose frequency has not been shifted by the first shift processing unit 32a. ｒｅｖ FIG. 8 is an explanatory diagram showing the spectrum SPC(H(i), W(j), θ(k), n, Rb) of (H(i), W(j), θ(k), n, Rb). The FFT bins on the horizontal axis of FIG. 8 correspond to range bins. Even if sensor 1 is a conical scan type sensor, if H(i), W(j), and θ(k) in the spectrum SPC(H(i), W(j), θ(k)) are close to the three elements contained in the wind vector corresponding to the wind vector in the wind observation area, the range bin corresponding to the largest spectral component will hardly change.

[0046] The first signal integration processing unit 32b integrates N spectra SPC(H(i), W(j), θ(k), 1, Rb) to SPC(H(i), W(j), θ(k), N, Rb) for each wind vector (H(i), W(j), θ(k)) for each range bin Rb (Rb=1, 2, ..., RB) as shown in the following equation (4) (step ST4 in FIG. 4). The first signal integration processing unit 32b integrates N spectra SPC(H(i), W(j), θ(k), 1, Rb) to SPC(H(i), W(j), θ(k), N, Rb) for each range bin Rb (Rb=1, 2, ..., RB) after integration ｉｎｔ (H(i), W(j), θ(k), Rb) is output to the wind vector selection unit 33.

[0047]

[0048] The wind vector selection unit 33 receives the integrated spectrum SPC for each range bin Rb (Rb=1, 2, . . . , RB) from the first signal integration processing unit 32b. ｉｎｔ(H(i), W(j), θ(k), Rb). The wind vector selector 33 obtains the integrated spectrum SPC for each range bin Rb (Rb=1, 2, ..., RB). ｉｎｔ Among the multiple spectral components contained in (H(i), W(j), θ(k), Rb), the maximum spectral component is extracted as a peak value P(H(i), W(j), θ(k), Rb). The wind vector selection unit 33 compares the (I×J×K) peak values ​​P(H(i), W(j), θ(k), Rb) with each other for each range bin Rb (Rb=1, 2, ..., RB), and thereby extracts the maximum peak value P(H(i), W(j), θ(k), Rb) among the (I×J×K) peak values ​​P(H(i), W(j), θ(k), Rb). ｍａｘ The wind vector selection unit 33 selects the wind vector (H, W, θ) corresponding to the wind vector of the wind observation area from among the (I×J×K) wind vectors (H(i), W(j), θ(k)), and selects the wind vector (H, W, θ) with the maximum peak value P ｍａｘ The wind vector corresponding to (Rb) is selected (step ST5 in FIG. 4).

[0049] Maximum peak value P ｍａｘ The wind vector corresponding to (Rb) has a maximum peak value P ｍａｘ The integrated spectrum SPC containing (Rb) ｉｎｔ (H(i), W(j), θ(k), Rb) is the wind vector (H(i), W(j), θ(k)). That is, the maximum peak value P ｍａｘ The wind vector corresponding to (Rb) has a maximum peak value P ｍａｘ The integrated spectrum SPC containing (Rb) ｉｎｔ The frequency shift amount f used to calculate (H(i), W(j), θ(k), Rb) ｄ The wind vector (H(i), W(j), θ(k)) corresponds to (H(i), W(j), θ(k), AZ(n), Rb).

[0050] The wind vector selection unit 33 selects the maximum peak value P ｍａｘ(Rb) is compared with a threshold value Th. The threshold value Th may be stored in the internal memory of the wind vector selection unit 33, or may be provided from outside the wind observation device 3. For example, the maximum noise amount in the wind observation system, or a value obtained by adding a margin to the maximum noise amount, may be used as the threshold value Th. In addition, for example, the maximum peak value P ｍａｘ (Rb). The wind vector selection unit 33 may select the maximum peak value P ｍａｘ If (Rb) is greater than the threshold value Th, the maximum peak value P ｍａｘ The wind vector selection unit 33 outputs the wind vector corresponding to the maximum peak value P ｍａｘ The wind vector selection unit 33 outputs the wind speed value of the horizontal wind H, the wind speed value of the vertical wind W, and the wind direction θ as three elements included in the wind vector corresponding to (Rb) to, for example, a display device (not shown). ｍａｘ If (Rb) is equal to or less than the threshold value Th, the maximum peak value P ｍａｘ The wind vector corresponding to (Rb) is not output because it is determined that the wind vector is not an appropriate wind vector.

[0051] In the wind observation device 3 shown in FIG. ｍａｘ Only when (Rb) is greater than the threshold value Th, the wind vector selection unit 33 selects the maximum peak value P ｍａｘ (Rb). However, this is only an example, and the maximum peak value P ｍａｘ Regardless of whether (Rb) is greater than the threshold value Th, the wind vector selection unit 33 selects the maximum peak value P ｍａｘ In the wind observation device 3 shown in FIG. 1, the wind vector selection unit 33 selects the maximum peak value P ｍａｘ The wind vector corresponding to (Rb) is output to a display device (not shown). ｍａｘ The output destination of the wind vector corresponding to (Rb) is not limited to a display device, but may be, for example, output to a weather observation site (not shown).

[0052] In the first embodiment described above, the wind observation device 3 is configured to include a received signal acquisition unit 31 that acquires received signals of each scattered light from a conical scan sensor 1 that repeatedly emits laser light toward a wind observation area and receives scattered light of each laser light scattered by aerosols present in the wind observation area, and a signal integration unit 32 that shifts the frequency of each received signal acquired by the received signal acquisition unit 31 using frequency shift amounts corresponding to each of a plurality of different wind vectors and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector. The wind observation device 3 also includes a wind vector selection unit 33 that selects, from among the plurality of wind vectors, a wind vector corresponding to the wind vector in the wind observation area based on the spectrum of the received signal integrated by the signal integration unit 32 for each wind vector. Therefore, the wind observation device 3 can increase the SNR of the received signal compared to the wind observation device disclosed in Non-Patent Document 1, thereby preventing deterioration in the calculation accuracy of the wind vector.

[0053] Second Embodiment In a second embodiment, a wind observation device 3 will be described, in which a signal integrator 34 calculates the spectrum of each received signal acquired by a received signal acquirer 31, and includes a second shift processor 34a that shifts the frequency of the spectrum of each received signal using a frequency shift amount corresponding to each wind vector.

[0054] Figure 9 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 2. In Figure 9, the same reference numerals as in Figure 1 indicate the same or corresponding parts, and detailed explanations will be omitted. Figure 10 is a hardware configuration diagram showing the hardware of the wind observation device 3 according to embodiment 2. In Figure 10, the same reference numerals as in Figure 2 indicate the same or corresponding parts, and detailed explanations will be omitted. The wind observation system shown in Figure 9 includes a sensor 1, an A / D converter 2, and a wind observation device 3.

[0055] The wind observation device 3 includes a received signal acquisition unit 31, a signal integrator 34, and a wind vector selector 33. The signal integrator 34 is realized, for example, by a signal integration circuit 44 shown in FIG. 10. The signal integrator 34 includes a second shift processor 34a and a second signal integration processor 34b. The signal integrator 34 shifts the frequency of each received signal acquired by the received signal acquisition unit 31 using frequency shift amounts corresponding to each of a plurality of different wind vectors, and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector.

[0056] The second shift processing unit 34a acquires received data as received signals of scattered light of each laser beam from the received signal acquisition unit 31. The second shift processing unit 34a calculates the spectrum of each received data by performing FFT on each received data. The second shift processing unit 34a shifts the frequency of the spectrum of each received data using a frequency shift amount corresponding to each wind vector. The frequency shift by the second shift processing unit 34a is a shift in the frequency domain. The second shift processing unit 34a outputs the frequency-shifted spectrum for each wind vector to the second signal integration processing unit 34b.

[0057] The second signal integration processing unit 34b acquires the frequency-shifted spectrum for each wind vector from the second shift processing unit 34a. The second signal integration processing unit 34b integrates the multiple spectra for each wind vector. The second signal integration processing unit 34b outputs the integrated spectrum for each wind vector to the wind vector selection unit 33.

[0058] 9, it is assumed that the received signal acquisition unit 31, the signal integration unit 34, and the wind vector selection unit 33, which are components of the wind observation device 3, are each realized by dedicated hardware as shown in Fig. 10. That is, it is assumed that the wind observation device 3 is realized by a received signal acquisition circuit 41, a signal integration circuit 44, and a wind vector selection circuit 43. Each of the received signal acquisition circuit 41, the signal integration circuit 44, and the wind vector selection circuit 43 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination of these.

[0059] The components of the wind observation device 3 are not limited to those realized by dedicated hardware, and the wind observation device 3 may be realized by software, firmware, or a combination of software and firmware. When the wind observation device 3 is realized by software, firmware, or the like, a program for causing a computer to execute the respective processing procedures of the received signal acquisition unit 31, the signal integration unit 34, and the wind vector selection unit 33 is stored in a memory 51 shown in Fig. 3. Then, a processor 52 shown in Fig. 3 executes the program stored in the memory 51.

[0060] 10 shows an example in which each of the components of the wind observation device 3 is realized by dedicated hardware, while Fig. 3 shows an example in which the wind observation device 3 is realized by software, firmware, etc. However, this is only one example, and some of the components in the wind observation device 3 may be realized by dedicated hardware, and the remaining components may be realized by software, firmware, etc.

[0061] Next, the operation of the wind observation system shown in Fig. 9 will be described. However, apart from the signal integrator 34, the system is the same as the wind observation system shown in Fig. 1. Therefore, only the operation of the signal integrator 34 will be described here.

[0062] The second shift processing unit 34a of the signal integrator 34 acquires each piece of received data S(AZ(n)) from the received signal acquirer 31. A distance resolution is set in advance in the second shift processing unit 34a. Similar to the first shift processing unit 32a shown in FIG. 1, the second shift processing unit 34a divides each piece of received data S(AZ(n)) into time intervals corresponding to the distance resolution. The second shift processing unit 34a saves the received data S(AZ(n), Rb) divided into time intervals corresponding to the distance resolution.

[0063] The internal memory of the second shift processing unit 34a stores (I×J×K) wind vectors (H(i), W(j), θ(k)). Similar to the first shift processing unit 32a shown in FIG. 1, the second shift processing unit 34a calculates a frequency shift amount f corresponding to the wind vector (H(i), W(j), θ(k)) (i=1, . . . , I; j=1, . . . , J; k=1, . . . , K) for each range bin Rb (Rb=1, 2, . . . , RB). ｄ Calculate (H(i), W(j), θ(k), AZ(n), Rb).

[0064] The second shift processing unit 34a calculates the spectrum SPC(AZ(n), Rb) of each received data S(AZ(n), Rb) by performing an FFT on each received data S(AZ(n), Rb), as shown in the following equation (5).

[0065]

[0066] The second shift processing unit 34a calculates a frequency shift amount f for each range bin Rb (Rb=1, 2, . . . , RB) as shown in the following equation (6). ｄ Based on (H(i), W(j), θ(k), AZ(n), Rb) (i = 1, ..., I; j = 1, ..., J; k = 1, ..., K), a bin shift amount Bin for shifting the frequency bin of the spectrum SPC(AZ(n, Rb)) is calculated. ｓｈｉｆｔ Calculate (H(i), W(j), θ(k), AZ(n), Rb).

[0067] In equation (6), df is the frequency resolution.

[0068] The second shift processing unit 34a calculates a frequency shift amount f for each range bin Rb (Rb=1, 2, . . . , RB). ｄ Bin shift amount Bin corresponding to (H(i), W(j), θ(k), AZ(n), Rb) ｓｈｉｆｔ The frequency bins of the spectrum SPC(AZ(n), Rb) are shifted using (H(i), W(j), θ(k), AZ(n)) (i = 1, ..., I; j = 1, ..., J; k = 1, ..., K). Note that when the number of spectral points of the spectrum SPC(AZ(n), Rb) is M and the frequency bins are to be shifted in the positive direction by, for example, G points, the second shift processing unit 34a shifts the frequency bins of the spectrum SPC(AZ(n), Rb) by G points and then embeds "0" in the first to Gth frequency bins. The second shift processing unit 34a outputs the spectrum SPC'(H(i), W(j), θ(k), n, Rb) (i = 1, ..., I; j = 1, ..., J; k = 1, ..., K) after frequency bin shifting for each range bin Rb (Rb = 1, 2, ..., RB) to the second signal integration processing unit 34b.

[0069] The second signal integration processing unit 34b acquires the spectrum SPC '(H (i), W (j), θ (k), n, Rb) (i = 1, ..., I; j = 1, ..., J; k = 1, ..., K) after frequency shifting for each range bin Rb (Rb = 1, 2, ..., RB) from the second shift processing unit 34a. The second signal integration processing unit 34b integrates N spectra SPC '(H (i), W (j), θ (k), 1, Rb) to SPC '(H (i), W (j), θ (k), N, Rb) for each wind vector (H (i), W (j), θ (k)) for each range bin Rb (Rb = 1, 2, ..., RB), as shown in the following equation (7). The second signal integration processing unit 34b outputs the integrated spectrum SPC for each range bin Rb (Rb=1, 2, . . . , RB). ｉｎｔ (H(i), W(j), θ(k), Rb) is output to the wind vector selection unit 33.

[0070]

[0071] In the second embodiment described above, the wind observation device 3 is configured so that the signal integrator 34 includes a second shift processor 34a that calculates the spectrum of each received signal acquired by the received signal acquirer 31 and shifts the frequency of the spectrum of each received signal using a frequency shift amount corresponding to each wind vector, and a second signal integration processor 34b that integrates multiple spectra for each wind vector after frequency shifting by the second shift processor 34a. Therefore, the wind observation device 3 can increase the SNR of the received signal more than the wind observation device disclosed in Non-Patent Document 1, and prevent deterioration in the calculation accuracy of the wind vector.

[0072] Third Embodiment In a third embodiment, a wind observation device 3 will be described in which a signal integrator 35 integrates the spectra of a plurality of frequency-shifted received signals and corrects the spectrum of the integrated received signals using the spectrum of the received signals when no noise floor exists.

[0073] Figure 11 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 3. In Figure 11, the same reference numerals as in Figures 1 and 9 indicate the same or corresponding parts, and detailed explanations will be omitted. Figure 12 is a hardware configuration diagram showing the hardware of the wind observation device 3 according to embodiment 3. In Figure 12, the same reference numerals as in Figures 2 and 10 indicate the same or corresponding parts, and detailed explanations will be omitted. The wind observation system shown in Figure 11 includes a sensor 1, an A / D converter 2, and a wind observation device 3.

[0074] The wind observation device 3 includes a received signal acquisition unit 31, a signal integrator 35, and a wind vector selector 33. The signal integrator 35 is realized, for example, by a signal integrator circuit 45 shown in FIG. 12 . Similar to either the signal integrator 32 shown in FIG. 1 or the signal integrator 34 shown in FIG. 9 , the signal integrator 35 shifts the frequency of each received signal acquired by the received signal acquisition unit 31 using frequency shift amounts corresponding to each of multiple different wind vectors, and integrates the spectra of the multiple frequency-shifted received signals for each wind vector. The signal integrator 35 also corrects the spectrum of the integrated received signal using the spectrum of the received signal when no noise floor exists. The signal integrator 35 outputs the corrected spectrum to the wind vector selector 33.

[0075] 11, it is assumed that the received signal acquisition unit 31, signal integration unit 35, and wind vector selection unit 33, which are components of the wind observation device 3, are each realized by dedicated hardware as shown in Fig. 12. That is, it is assumed that the wind observation device 3 is realized by a received signal acquisition circuit 41, a signal integration circuit 45, and a wind vector selection circuit 43. Each of the received signal acquisition circuit 41, the signal integration circuit 45, and the wind vector selection circuit 43 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination of these.

[0076] The components of the wind observation device 3 are not limited to those realized by dedicated hardware, and the wind observation device 3 may be realized by software, firmware, or a combination of software and firmware. When the wind observation device 3 is realized by software, firmware, or the like, a program for causing a computer to execute the processing procedures of the received signal acquisition unit 31, the signal integration unit 35, and the wind vector selection unit 33 is stored in a memory 51 shown in Fig. 3. Then, a processor 52 shown in Fig. 3 executes the program stored in the memory 51.

[0077] 12 shows an example in which each of the components of the wind observation device 3 is realized by dedicated hardware, while Fig. 3 shows an example in which the wind observation device 3 is realized by software, firmware, etc. However, this is only one example, and some of the components in the wind observation device 3 may be realized by dedicated hardware, and the remaining components may be realized by software, firmware, etc.

[0078] Next, the operation of the wind observation system shown in Fig. 11 will be described. However, apart from the signal integrator 35, the wind observation system is the same as the wind observation system shown in Fig. 1 or the wind observation system shown in Fig. 9. Therefore, only the operation of the signal integrator 35 will be described here.

[0079] The signal integrator 35, like the signal integrator 32 shown in FIG. 1, integrates N spectra SPC(H(i), W(j), θ(k), 1, Rb) to SPC(H(i), W(j), θ(k), N, Rb) for each wind vector (H(i), W(j), θ(k)), to obtain the integrated spectrum SPC ｉｎｔ The signal integrator 35 calculates (H(i), W(j), θ(k), Rb) as the received data S(j, Rb) when there is no noise floor. For example, the signal integrator 35 calculates the received data S(j, Rb) output from the received signal acquirer 31 when the optical amplifier 14 is OFF or the optical antenna 16 is shielded from light. ｎｏｉｓｅ (j, Rb). The noise floor includes, for example, colored noise. The signal integrator 35 obtains the received data S ｎｏｉｓｅ By performing FFT on (j, Rb), the noise spectrum SPC corresponding to the power of the noise floor is obtained. ｎｏｉｓｅ (N ｆｌ , Rb) are calculated. ｆｌ is the number of shots when acquiring the noise spectrum. ｆｌ suppresses noise variability and performs noise spectrum SPC ｎｏｉｓｅ (N ｆｌ , Rb) is set to a value such that the received data S(AZ(n), Rb) contains only the offset component of the received data S(AZ(n), Rb). For example, ｆｌ = 100,000.

[0080]

[0081] The signal integrator 35 calculates the integrated spectrum SPC as shown in the following equation (9): ｉｎｔ (H(i), W(j), θ(k), Rb) is the noise spectrum SPC ｎｏｉｓｅ (N ｆｌ , Rb) to remove the influence of the noise floor. ｉｎｔ (H(i), W(j), θ(k), Rb) as SPC ｉｎｔ '(H(i), W(j), θ(k), Rb) is output to the wind vector selection unit 33.

[0082]

[0083] Here, the signal integrator 35 calculates the spectrum SPC calculated by the above equation (4). ｉｎｔ (H(i), W(j), θ(k), Rb) is the spectral SPC ｎｏｉｓｅ (N ｆｌ , Rb) to remove the influence of the noise floor. However, this is only an example, and the signal integrator 35 uses the spectrum SPC calculated by the above equation (7) ｉｎｔ (H(i), W(j), θ(k), Rb) is the noise spectrum SPC ｎｏｉｓｅ (N ｆｌ , Rb) to remove the effect of the noise floor.

[0084] In the third embodiment described above, the wind observation device 3 is configured so that the signal integrator 35 integrates the spectra of multiple frequency-shifted received signals and corrects the spectrum of the integrated received signal using the spectrum of the received signal when no noise floor exists. Therefore, the wind observation device 3 can increase the SNR of the received signal more than the wind observation device disclosed in Non-Patent Document 1, preventing deterioration in the calculation accuracy of the wind vector, and can also remove the influence of the noise floor to improve the calculation accuracy of the wind vector.

[0085] Fourth Embodiment In a fourth embodiment, a wind observation device 3 in which the signal integrator 36 sets a plurality of wind vectors based on the wind vector previously selected by the wind vector selector 33 will be described.

[0086] Figure 13 is a configuration diagram showing a wind observation system including a wind observation device 3 according to embodiment 4. In Figure 13, the same reference numerals as in Figures 1, 9, and 11 indicate the same or corresponding parts, and detailed descriptions thereof will be omitted. Figure 14 is a hardware configuration diagram showing the hardware of the wind observation device 3 according to embodiment 4. In Figure 14, the same reference numerals as in Figures 2, 10, and 12 indicate the same or corresponding parts, and detailed descriptions thereof will be omitted. The wind observation system shown in Figure 13 includes a sensor 1, an A / D converter 2, and a wind observation device 3.

[0087] The wind observation device 3 includes a received signal acquisition unit 31, a signal integrator 36, and a wind vector selector 33. The signal integrator 36 is realized by, for example, a signal integrator circuit 46 shown in FIG. 14. Similar to the signal integrator 32 shown in FIG. 1, the signal integrator 34 shown in FIG. 9, or the signal integrator 35 shown in FIG. 11, the signal integrator 36 integrates the spectrum of a plurality of frequency-shifted received signals for each wind vector. However, unlike the signal integrators 32, 34, and 35, the signal integrator 36 sets (I' x J' x K') wind vectors (H(i), W(j), θ(k)) based on the wind vector previously selected by the wind vector selector 33, where 1≦I' ≦ I, 1≦J' ≦ J, and 1≦K' ≦ K. The signal accumulation unit 36 ​​shifts the frequency of each received signal acquired by the received signal acquisition unit 31 using a frequency shift amount corresponding to each of the (I' x J' x K') wind vectors (H(i), W(j), θ(k)), and accumulates the spectra of the multiple received signals after frequency shift for each wind vector.

[0088] In Fig. 13, it is assumed that the received signal acquisition unit 31, signal integration unit 36, and wind vector selection unit 33, which are components of the wind observation device 3, are each realized by dedicated hardware as shown in Fig. 14. In other words, it is assumed that the wind observation device 3 is realized by a received signal acquisition circuit 41, a signal integration circuit 46, and a wind vector selection circuit 43. Each of the received signal acquisition circuit 41, the signal integration circuit 46, and the wind vector selection circuit 43 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination of these.

[0089] The components of the wind observation device 3 are not limited to those realized by dedicated hardware, and the wind observation device 3 may be realized by software, firmware, or a combination of software and firmware. When the wind observation device 3 is realized by software or firmware, a program for causing a computer to execute the processing procedures of the received signal acquisition unit 31, the signal integration unit 36, and the wind vector selection unit 33 is stored in a memory 51 shown in Fig. 3. Then, a processor 52 shown in Fig. 3 executes the program stored in the memory 51.

[0090] 14 shows an example in which each of the components of the wind observation device 3 is realized by dedicated hardware, while Fig. 3 shows an example in which the wind observation device 3 is realized by software, firmware, etc. However, this is only one example, and some of the components in the wind observation device 3 may be realized by dedicated hardware, and the remaining components may be realized by software, firmware, etc.

[0091] Next, the operation of the wind observation system shown in Fig. 13 will be described. However, apart from the signal integrator 36, the wind observation system is the same as the wind observation system shown in Fig. 1, the wind observation system shown in Fig. 9, or the wind observation system shown in Fig. 11. Therefore, only the operation of the signal integrator 36 will be described here. The first wind observation process in the wind observation system shown in Fig. 13 is the same as the first wind observation process in the wind observation system shown in Fig. 1, the wind observation system shown in Fig. 9, or the wind observation system shown in Fig. 11.

[0092] In the second and subsequent wind observation processes in the wind observation system shown in FIG. 13, the signal integrator 36 uses the maximum peak value P ｍａｘ The signal integrator 36 obtains the wind vector corresponding to the maximum peak value P ｍａｘ Based on the wind vector corresponding to (Rb), (I' x J' x K') wind vectors (H(i), W(j), θ(k)) are set.

[0093] Specifically, the signal integrator 36 calculates the maximum peak value P ｍａｘ The wind speed value of the horizontal wind H included in the wind vector corresponding to (Rb) is used as the reference, and the wind speed value ±□□ of the reference wind speed value is set as H(i). ｍａｘ For example, if the wind speed value of the horizontal wind H included in the wind vector corresponding to (Rb) is 6 [m / s] and □□ is 2 [m / s], the signal integrator 36 sets 4, 5, 6, 7, and 8 [m / s] to H(i). In this example, I′=5. The signal integrator 36 calculates the maximum peak value P ｍａｘ The wind speed value of the vertical wind W included in the wind vector corresponding to (Rb) is used as the reference, and the wind speed value ±△△ of the reference wind speed value is set as W(j). ｍａｘ For example, if the wind speed value of the vertical wind W included in the wind vector corresponding to (Rb) is 3 [m / s] and △△ is 1 [m / s], the signal integrator 36 sets 2, 3, and 4 m / s to W(j). In this example, J'=3. The signal integrator 36 calculates the maximum peak value P ｍａｘThe wind direction θ included in the wind vector corresponding to (Rb) is used as the reference, and the wind direction ±00 of the reference wind direction θ is set to θ(k). ｍａｘ If the wind direction θ included in the wind vector corresponding to (Rb) is, for example, 240 degrees and XX is 90 degrees, the signal integrator 36 sets θ(k) to a value in increments of, for example, 5 degrees within the range of 150 to 330 degrees. In this example, K'=37.

[0094] The signal integrator 36 shifts the frequency of each received signal acquired by the received signal acquirer 31 using a frequency shift amount corresponding to each of the (I' x J' x K') wind vectors (H(i), W(j), θ(k)), and integrates the spectra of the multiple received signals after frequency shifting for each wind vector. The process of integrating the spectra by the signal integrator 36 is similar to the process of integrating the spectra by the signal integrator 32 shown in Figure 1, the process of integrating the spectra by the signal integrator 34 shown in Figure 9, or the process of integrating the spectra by the signal integrator 35 shown in Figure 11, and therefore a detailed description thereof will be omitted.

[0095] In the fourth embodiment described above, the signal integrator 36 sets multiple wind vectors based on the wind vector previously selected by the wind vector selector 33. The signal integrator 36 then shifts the frequency of each received signal acquired by the received signal acquirer 31 using a frequency shift amount corresponding to each of the multiple set wind vectors, and integrates the spectra of the multiple frequency-shifted received signals for each wind vector. Therefore, like the wind observation device 3 shown in FIG. 1 , the wind observation device 3 shown in FIG. 13 can increase the SNR of the received signal compared to the wind observation device disclosed in Non-Patent Document 1, preventing deterioration in wind vector calculation accuracy, and can also reduce the processing load compared to the wind observation device 3 shown in FIG. 1.

[0096] In the first to fourth embodiments, the signal integrators 32, 34, 35, and 36 calculate all of the frequency shift amounts corresponding to each of the multiple wind vectors that are different from each other before shifting the frequency of each piece of reception data acquired by the reception signal acquisition unit 31. Then, the signal integrator 32 etc. shifts the frequency of each piece of reception data using each frequency shift amount, and integrates the spectrum of the multiple pieces of reception data after frequency shift for each wind vector. However, this is merely an example, and the signal integrator 32 etc. may first calculate the frequency shift amount corresponding to each of any two of the multiple wind vectors, shift the frequency of each piece of reception data using each frequency shift amount, and integrate the spectrum of the multiple pieces of reception data after frequency shift for each wind vector. In this case, the wind vector selector 33 selects the maximum peak value P based on the spectrum of the reception data after integration for each of the two wind vectors. ｍａｘ (Rb) to find the wind vector corresponding to the maximum peak value P ｍａｘ The process of searching for the wind vector corresponding to (Rb) is a process of extracting the maximum spectral component as a peak value from among the multiple spectral components contained in each integrated spectrum, and searching for the peak value that is the maximum value among the multiple extracted peak values. Normally, if there are only two wind vectors, it is not possible to search for the peak value that is the maximum value. The signal integration unit 32 etc. selects the maximum peak value P by the wind vector selection unit 33. ｍａｘ If a wind vector corresponding to (Rb) has not been found, the wind vector selector 33 calculates a frequency shift amount corresponding to a wind vector that has not yet been used among the multiple wind vectors, shifts the frequency of the received data using the frequency shift amount, and integrates the spectra of the multiple received data after frequency shift. The wind vector selector 33 calculates the maximum peak value P ｍａｘ The signal integrator 32 and the wind vector selector 33 search for the wind vector corresponding to the maximum peak value P ｍａｘThe wind vector selection unit 33 repeats the same process until it can find the wind vector corresponding to the maximum peak value P ｍａｘ If a wind vector corresponding to (Rb) can be found, this wind vector is selected as the wind vector corresponding to the wind vector of the wind observation area.

[0097] In addition, the present disclosure allows for free combination of the respective embodiments, modification of any of the components of the respective embodiments, or omission of any of the components of the respective embodiments.

[0098] The present disclosure is suitable for a wind observation device, a wind observation method, and a wind observation system.

[0099] REFERENCE SIGNS LIST 1 Sensor, 2 A / D converter, 3 Wind observation device, 11 Optical oscillator, 12 Coupler, 13 Optical modulator, 14 Optical amplifier, 15 Optical circulator, 16 Optical antenna, 17 Scanner, 18 Scanner driver, 19 Wave-combining coupler, 20 Optical receiver, 31 Received signal acquisition unit, 32 Signal integration unit, 32a First shift processing unit, 32b First signal integration processing unit, 33 Wind vector selection unit, 34 Signal integration unit, 34a Second shift processing unit, 34b Second signal integration processing unit, 35 Signal integration unit, 36 Signal integration unit, 41 Received signal acquisition circuit, 42 Signal integration circuit, 43 Wind vector selection circuit, 44 Signal integration circuit, 45 Signal integration circuit, 46 Signal integration circuit, 51 Memory, 52 Processor.

Claims

1. A wind observation device comprising: a received signal acquisition unit that acquires received signals of each scattered light from a conical scan type sensor that repeatedly emits laser light toward a wind observation area and receives scattered light of each laser light scattered by aerosols present in the wind observation area; a signal integration unit that shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each of a plurality of different wind vectors and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector; and a wind vector selection unit that selects from the plurality of wind vectors a wind vector that corresponds to the wind vector of the wind observation area based on the spectrum of the received signal after integration by the signal integration unit for each wind vector.

2. A wind observation device as claimed in claim 1, characterized in that the signal integration unit uses each wind vector to calculate the amount of frequency shift corresponding to each wind vector.

3. The wind observation device according to claim 1, characterized in that the signal integration unit comprises: a first shift processing unit that shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each wind vector; and a first signal integration processing unit that calculates the spectrum of each received signal after the frequency shift by the first shift processing unit and integrates a plurality of spectra for each wind vector.

4. The wind observation device according to claim 1, characterized in that the signal integration unit comprises: a second shift processing unit that calculates the spectrum of each received signal acquired by the received signal acquisition unit and shifts the frequency of the spectrum of each received signal using a frequency shift amount corresponding to each wind vector; and a second signal integration processing unit that integrates multiple spectra after frequency shifting by the second shift processing unit for each wind vector.

5. The wind observation device described in claim 1, characterized in that the wind vector selection unit identifies the peak value contained in the spectrum of the received signal after integration by the signal integration unit for each wind vector, compares the peak values ​​for the multiple wind vectors with each other, and selects from the multiple wind vectors a wind vector that corresponds to the wind vector of the wind observation area based on the comparison result of the peak values.

6. The wind observation device described in claim 1, characterized in that each of the multiple wind vectors includes three elements: horizontal wind speed value, vertical wind speed value, and wind direction, and each wind vector has one or more of the three elements that differ from the other wind vectors, and the wind vector selection unit outputs the three elements included in the wind vector of the wind observation area.

7. A wind observation device as described in claim 1, characterized in that the signal accumulation unit accumulates the spectra of multiple received signals after frequency shifting, and corrects the spectrum of the accumulated received signal using the spectrum of the received signal when no noise floor exists.

8. The wind observation device described in claim 1, characterized in that the signal integration unit sets the multiple wind vectors based on the wind vector previously selected by the wind vector selection unit, shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each of the multiple set wind vectors, and integrates the spectra of the multiple received signals after frequency shifting for each wind vector.

9. A wind observation method, in which a laser light is repeatedly emitted toward a wind observation area, and a received signal acquisition unit acquires received signals of each scattered light from a conical scan type sensor that receives scattered light of each laser light scattered by aerosols present in the wind observation area, a signal integration unit shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each of a plurality of different wind vectors, and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector, and a wind vector selection unit selects a wind vector that corresponds to the wind vector of the wind observation area from among the plurality of wind vectors based on the spectrum of the received signal after integration by the signal integration unit for each wind vector.

10. A wind observation system comprising: a conical scan type sensor that repeatedly emits laser light toward a wind observation area and receives scattered light of each laser light scattered by aerosols present in the wind observation area; a received signal acquisition unit that acquires a received signal of each scattered light from the sensor; a signal integration unit that shifts the frequency of each received signal acquired by the received signal acquisition unit using a frequency shift amount corresponding to each of a plurality of different wind vectors and integrates the spectra of the plurality of frequency-shifted received signals for each wind vector; and a wind vector selection unit that selects from the plurality of wind vectors a wind vector that corresponds to the wind vector of the wind observation area based on the spectrum of the received signal after integration by the signal integration unit for each wind vector.

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