Frequency detection device, frequency detection method, and frequency detection circuit

Abstract

Provided is a frequency detection device (8) comprising: a frequency / phase calculation unit (11) that calculates the frequency of first quantized data and the phase of the first quantized data of a signal to be measured; and a phase difference calculation unit (12) that calculates the phase of second quantized data, which is data delayed from the first quantized data, and calculates the phase difference between the phase of the first quantized data and the phase of the second quantized data. The frequency detection device (8) comprises: a phase difference calibration unit (13) that acquires calibration data corresponding to the phase difference calculated by the phase difference calculation unit 12 and calibrates the phase difference according to the calibration data; a folding order calculation unit (14) that calculates the Nyquist folding order of the first quantized data on the basis of the phase difference after calibration by the phase difference calibration unit (13); and a frequency calculation unit 15 that calculates the frequency of the signal to be measured using the frequency calculated by the frequency / phase calculation unit (11) and the Nyquist folding order calculated by the folding order calculation unit (14).

Description

Frequency detection device, frequency detection method, and frequency detection circuit

[0001] This disclosure relates to a frequency detection device, a frequency detection method, and a frequency detection circuit.

[0002] There is a frequency detection circuit that calculates the frequency of a signal to be measured. As such a frequency detection circuit, for example, Patent Document 1 discloses a frequency detection circuit comprising a first sample-and-hold circuit, a second sample-and-hold circuit, and a frequency calculation circuit. The first sample-and-hold circuit undersamples the signal to be measured using a first clock signal and outputs the signal to be measured after undersampling. The second sample-and-hold circuit undersamples the signal to be measured using a second clock signal that has the same frequency as the first clock signal but a different phase from the first clock signal, and outputs the signal to be measured after undersampling. The frequency calculation circuit comprises a first quantizer that quantizes the output signal of the first sample-and-hold circuit and outputs first quantized data, which is the signal after quantization, and a second quantizer that quantizes the output signal of the second sample-and-hold circuit and outputs second quantized data, which is the signal after quantization. The frequency calculation circuit calculates the frequency of the first quantized data, calculates the order of undersampling for the signal under test from the phase difference between the phase of the first quantized data and the phase of the second quantized data, and calculates the frequency of the signal under test from the frequency of the first quantized data and the order of undersampling.

[0003] International Publication No. 2020-152764

[0004] The frequency detection circuit disclosed in Patent Document 1 had the problem that it required the implementation of a first sample-and-hold circuit and a second sample-and-hold circuit before the frequency calculation circuit.

[0005] This disclosure was made to solve the above-mentioned problems, and aims to provide a frequency detection device that can calculate the frequency of a signal under measurement without implementing two sample-and-hold circuits.

[0006] The frequency detection device according to this disclosure includes a frequency-phase calculation unit that calculates the frequency and phase of a first quantized data, which is a quantized signal of the signal to be measured; and a phase difference calculation unit that calculates the phase of a second quantized data, which is delayed compared to the first quantized data, and calculates the phase difference between the phase of the first quantized data and the phase of the second quantized data. The frequency detection device also includes a phase difference calibration unit that acquires calibration data corresponding to the phase difference calculated by the phase difference calculation unit and calibrates the phase difference according to the calibration data; an aliasing order calculation unit that calculates the Nyquist aliasing order of the first quantized data based on the phase difference after calibration by the phase difference calibration unit; and a frequency calculation unit that calculates the frequency of the signal to be measured using the frequency calculated by the frequency-phase calculation unit and the Nyquist aliasing order calculated by the aliasing order calculation unit.

[0007] According to this disclosure, the frequency of the signal under test can be calculated without implementing two sample-and-hold circuits.

[0008] This is a configuration diagram showing a frequency detection circuit including a frequency detection device 8 according to Embodiment 1. This is a hardware configuration diagram showing the hardware of the frequency detection device 8 according to Embodiment 1. This is a hardware configuration diagram of a computer when the frequency detection device 8 is implemented by software or firmware, etc. This is a flowchart showing the frequency detection method, which is the processing procedure of the frequency detection device 8. This is an explanatory diagram showing the frequency of the clock signal, the Nyquist frequency, and the Nyquist zone. Calibration data θ ｃａｌ (f ｏｕｔ ) and phase difference Δθ ｃｌｋ This is an explanatory diagram illustrating an example. Calibration data θ for each phase difference Δθ. ｃａｌ (f ｏｕｔ ) and phase difference Δθ ｃｌｋ This is an explanatory diagram showing the following. This is a configuration diagram showing a frequency detection circuit including the frequency detection device 8 according to Embodiment 2. This is a hardware configuration diagram showing the hardware of the frequency detection device 8 according to Embodiment 2. Frequency f ｏｕｔｍ The first phase difference Δθ of (m = 1, ..., M) １，ｍ This is an explanatory diagram showing the linear interpolation result for frequency f.ｏｕｔｍ The second phase difference Δθ for (m = 1, ···, M) ２，ｍ It is an explanatory diagram showing the linear interpolation result of. It is a block diagram showing a frequency detection circuit including a frequency detection device 8 according to Embodiment 3.

[0009] Hereinafter, in order to explain the present disclosure in more detail, embodiments for implementing the present disclosure will be described with reference to the accompanying drawings.

[0010] Embodiment 1. FIG. 1 is a block diagram showing a frequency detection circuit including a frequency detection device 8 according to Embodiment 1. FIG. 2 is a hardware configuration diagram showing the hardware of the frequency detection device 8 according to Embodiment 1. The frequency detection circuit shown in FIG. 1 includes a clock signal source 1, a distributor 2, a quantization unit 3, and a frequency detection device 8. The quantization unit 3 includes delay circuits 4 and 5 and quantizers 6 and 7.

[0011] The clock signal source 1 is realized by, for example, a voltage-controlled oscillator, a crystal oscillator, or a general-purpose signal generator. The clock signal source 1 oscillates a clock signal with a frequency f ｃｌｋ and outputs the clock signal to the quantization unit 3. The distributor 2 divides the measurement signal, which is the signal to be frequency-detected, into two. The distributor 2 outputs one of the measurement signals after distribution to the delay circuit 4 of the quantization unit 3, and outputs the other measurement signal after distribution to the delay circuit 5 of the quantization unit 3.

[0012] The quantization unit 3 quantizes one of the measurement signals after distribution and outputs the first quantization data, which is the measurement signal after quantization, to the frequency detection device 8. The quantization unit 3 quantizes the other measurement signal after distribution and outputs the second quantization data, which is the measurement signal after quantization, to the frequency detection device 8. The second quantization data is data that is delayed from the first quantization data.

[0013] The delay circuit 4 delays one of the measurement signals after distribution by a delay time τ １ and outputs the delayed measurement signal to the quantizer 6. The delay circuit 5 delays the other measurement signal after distribution by a delay time τ ２ and outputs the delayed measurement signal to the quantizer 7. The delay time τ ２is the delay time τ １ It is longer than the line length L. The delay circuit 4 is longer than the line length L. １ This is realized by the track, and the delay circuit 5 is the track length L ２ If implemented by the railway line, the track length L ２ The track length L １ Longer than, delay time τ １ and delay time τ ２ The delay time difference Δτ is (L ２ -L １ It is expressed as ) / v, where v is the propagation speed of the signal under test in the delay circuits 4 and 5. In the frequency detection circuit shown in Figure 1, the quantization unit 3 is equipped with two delay circuits 4 and 5. However, this is just one example, and the quantization unit 3 may be equipped with a delay circuit 5 instead of a delay circuit 4. In this case, the delay time difference Δτ is L ２ It is represented by / v.

[0014] Quantizers 6 and 7 are implemented, for example, by an ADC (Analog to Digital Converter). Quantizer 6 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the signal under test after delay by the delay circuit 4. The quantizer 6 outputs the first quantized data, which is the signal under test after quantization, to the frequency detection device 8. The quantizer 7 uses the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the signal under test after delay by the delay circuit 5. The quantizer 7 outputs the second quantized data, which is the signal under test after quantization, to the frequency detection device 8.

[0015] The frequency detection device 8 includes a frequency phase calculation unit 11, a phase difference calculation unit 12, a phase difference calibration unit 13, an aliasing order calculation unit 14, a frequency calculation unit 15, and a calibration data storage unit 16. The frequency phase calculation unit 11 is implemented, for example, by the frequency phase calculation circuit 21 shown in Figure 2. The frequency phase calculation unit 11 acquires first quantized data from the quantizer 6. The frequency phase calculation unit 11 calculates the frequency f of the first quantized data. ｏｕｔ and the phase θ of the first quantized data ｏｕｔ１Each of these is calculated. Specifically, the frequency phase calculation unit 11 converts the first quantized data into a signal in the frequency domain, and calculates the frequency f of the first quantized data from the frequency bin of the peak frequency component in the signal in the frequency domain. ｏｕｔ and the phase θ of the first quantized data ｏｕｔ１ Each of these is identified. The frequency phase calculation unit 11 determines the frequency f of the first quantized data. ｏｕｔ The frequency calculation unit 15 outputs information indicating the phase θ of the first quantized data. ｏｕｔ１ Information indicating this is output to the phase difference calculation unit 12.

[0016] The phase difference calculation unit 12 is implemented, for example, by the phase difference calculation circuit 22 shown in Figure 2. The phase difference calculation unit 12 acquires second quantization data from the quantizer 7 and the phase θ of the first quantization data from the frequency phase calculation unit 11. ｏｕｔ１ Information indicating this is obtained. The phase difference calculation unit 12 calculates the phase θ of the second quantized data. ｏｕｔ２ Specifically, the phase difference calculation unit 12 converts the second quantized data into a frequency domain signal and calculates the phase θ of the second quantized data from the frequency bin of the peak frequency component in the frequency domain signal. ｏｕｔ２ The phase difference calculation unit 12 determines the phase θ of the first quantized data. ｏｕｔ１ and the phase θ of the second quantized data ｏｕｔ２ The phase difference Δθ is calculated. The phase difference calculation unit 12 outputs information indicating the phase difference Δθ to the phase difference calibration unit 13.

[0017] The phase difference calibration unit 13 is implemented, for example, by the phase difference calibration circuit 23 shown in Figure 2. The phase difference calibration unit 13 acquires information indicating the phase difference Δθ from the phase difference calculation unit 12. The phase difference calibration unit 13 acquires calibration data θ corresponding to the phase difference Δθ from the calibration data storage unit 16. ｃａｌ (f ｏｕｔ The phase difference calibration unit 13 obtains the calibration data θ. ｃａｌ (f ｏｕｔ The phase difference Δθ is calibrated according to the following. The phase difference calibration unit 13 calibrates the phase difference Δθ after calibration. ｃａｌ Information indicating this is output to the loopback order calculation unit 14.

[0018] The aliasing order calculation unit 14 is implemented, for example, by the aliasing order calculation circuit 24 shown in Figure 2. The aliasing order calculation unit 14 receives the phase difference Δθ after calibration from the phase difference calibration unit 13. ｃａｌ Information indicating the phase difference Δθ is obtained from the calibration data storage unit 16. ｃｌｋ Information indicating the phase difference Δθ is obtained. ｃｌｋ Δθ is the phase difference between the phase of a first calibration signal having a frequency in the first-order Nyquist region and the phase of an nth calibration signal having a frequency in the nth-order Nyquist region. n is an integer greater than or equal to 2. The frequencies of the first calibration signal and the nth calibration signal are the same. The aliasing order calculation unit 14 calculates the phase difference Δθ after calibration by the phase difference calibration unit 13. ｃａｌ Based on this, the Nyquist aliasing order Fo of the first quantized data is calculated and the Nyquist aliasing order Fo is output to the frequency calculation unit 15. Specifically, the aliasing order calculation unit 14 calculates the phase difference Δθ ｃｌｋ Phase difference Δθ ｃｌｋ The function is divided by , and the result of that division is output to the frequency calculation unit 15 as the Nyquist aliasing order Fo.

[0019] The frequency calculation unit 15 is implemented, for example, by the frequency calculation circuit 25 shown in Figure 2. The frequency calculation unit 15 receives the frequency f of the first quantized data from the frequency phase calculation unit 11. ｏｕｔ Information indicating this is obtained, and the Nyquist aliasing order Fo is obtained from the aliasing order calculation unit 14. The frequency calculation unit 15 obtains the frequency f of the first quantized data. ｏｕｔ Using the Nyquist aliasing order Fo, the frequency f of the signal under measurement is used. ＲＦ Calculate.

[0020] The calibration data storage unit 16 is implemented, for example, by the calibration data storage circuit 26 shown in Figure 2. The calibration data storage unit 16 stores calibration data θ corresponding to the phase difference Δθ. ｃａｌ (f ｏｕｔ ) and the phase difference Δθ ｃｌｋ It stores the following. The frequency detection device 8 shown in Figure 1 has a built-in calibration data storage unit 16. However, this is just one example, and the calibration data storage unit 16 may be provided outside the frequency detection device 8.

[0021] In Figure 1, it is assumed that the frequency detection device 8's components—the frequency phase calculation unit 11, the phase difference calculation unit 12, the phase difference calibration unit 13, the aliasing order calculation unit 14, the frequency calculation unit 15, and the calibration data storage unit 16—are each implemented by dedicated hardware as shown in Figure 2. Specifically, it is assumed that the frequency detection device 8 is implemented by a frequency phase calculation circuit 21, a phase difference calculation circuit 22, a phase difference calibration circuit 23, an aliasing order calculation circuit 24, a frequency calculation circuit 25, and a calibration data storage circuit 26.

[0022] The calibration data storage circuit 26 may include, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), magnetic disks, flexible disks, optical disks, compact disks, minidiscs, or DVDs (Digital Versatile Discs). Furthermore, each of the frequency-phase calculation circuit 21, phase difference calculation circuit 22, phase difference calibration circuit 23, aliasing order calculation circuit 24, and frequency calculation circuit 25 can be, 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 thereof.

[0023] The components of the frequency detection device 8 are not limited to those implemented by dedicated hardware; the frequency detection device 8 may also be implemented by software, firmware, or a combination of software and firmware. The software or firmware is stored as a program in the computer's memory. A computer refers to hardware that executes programs, and includes, for example, a CPU (Central Processing Unit), GPU (Graphics Processing Unit), central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, or DSP (Digital Signal Processor).

[0024] Figure 3 is a hardware configuration diagram of a computer when the frequency detection device 8 is implemented by software or firmware. When the frequency detection device 8 is implemented by software or firmware, the calibration data storage unit 16 is configured on the computer's memory 31. Programs that cause the computer to execute the respective processing procedures in the frequency phase calculation unit 11, phase difference calculation unit 12, phase difference calibration unit 13, aliasing order calculation unit 14, and frequency calculation unit 15 are stored in the memory 31. The computer's processor 32 then executes the programs stored in the memory 31.

[0025] Furthermore, Figure 2 shows an example in which each component of the frequency detection device 8 is implemented by dedicated hardware, and Figure 3 shows an example in which the frequency detection device 8 is implemented by software or firmware, etc. However, this is merely one example, and some components of the frequency detection device 8 may be implemented by dedicated hardware, while the remaining components may be implemented by software or firmware, etc.

[0026] Next, the operation of the frequency detection circuit shown in Figure 1 will be explained. Figure 4 is a flowchart of the frequency detection method, which is the processing procedure of the frequency detection device 8. When the distributor 2 receives the signal to be measured as the signal to be frequency detected, it divides the signal to be measured into two. The distributor 2 outputs one of the divided signals to be measured to the delay circuit 4 of the quantization unit 3, and outputs the other divided signal to be measured to the delay circuit 5 of the quantization unit 3.

[0027] The delay circuit 4 delays one of the measured signals after distribution by a delay time τ １ The signal under test is delayed by a certain amount of time, and the delayed signal is output to the quantizer 6. The delay circuit 5 delays the other signal under test, which has been distributed, by a delay time τ. ２ The signal is delayed by a certain amount, and the delayed signal is output to the quantizer 7. Delay time τ １ and delay time τ ２ The delay time difference Δτ is, as described above, (L ２ -L １ It is expressed as ) / v.

[0028] The quantizer 6 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the signal under test after delay by the delay circuit 4. The quantizer 6 outputs the first quantized data, which is the signal under test after quantization, to the frequency phase calculation unit 11. At this time, the frequency f of the signal under test ＲＦ However, frequency f ｃｌｋ The Nyquist frequency f is half the frequency of f. ｃｌｋ If it is higher than / 2, a phenomenon called aliasing occurs. As a result, the frequency f of the first quantized data calculated by the frequency phase calculation unit 11 ｏｕｔ The calculation result is the Nyquist frequency f ｃｌｋ This indicates frequencies that exist in the first Nyquist zone, which is lower than / 2.

[0029] Figure 5 is an explanatory diagram showing the frequency, Nyquist frequency, and Nyquist zone of the clock signal. In the example of Figure 5, the frequency of the clock signal f ｃｌｋ Since is α [MHz], the Nyquist frequency f ｃｌｋ / 2 is α / 2 [MHz]. The first Nyquist zone is the bandwidth from DC (direct current) to α / 2 [MHz], the second Nyquist zone is the bandwidth from α / 2 [MHz] to α [MHz], the third Nyquist zone is the bandwidth from α [MHz] to 3α / 2 [MHz], the fourth Nyquist zone is the bandwidth from 3α / 2 [MHz] to 2α [MHz], and the fifth Nyquist zone is the bandwidth from 2α [MHz] to 5α / 2 [MHz]. The frequency f of the signal under measurement. ＲＦ However, if the frequency is in the second to fifth Nyquist zones, the frequency f of the first quantized data calculated by the frequency phase calculation unit 11 ｏｕｔ The calculation result indicates the frequencies present in the first Nyquist zone.

[0030] The quantizer 7 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the signal under test after delay by the delay circuit 5. The quantizer 7 outputs the second quantized data, which is the signal under test after quantization, to the frequency detection device 8. The second quantized data is delayed compared to the first quantized data.

[0031] The frequency phase calculation unit 11 acquires first quantized data from the quantizer 6. The frequency phase calculation unit 11 converts the first quantized data into a frequency domain signal, for example, by performing an FFT (Fast Fourier Transform) on the first quantized data. The frequency phase calculation unit 11 calculates the frequency f of the first quantized data from the frequency bins of the frequency components of the peaks in the frequency domain signal. ｏｕｔ and the phase θ of the first quantized data ｏｕｔ１ Identify each of them (step ST1 in Figure 4). From the frequency bins of the peak frequency components, the frequency f of the first quantized data ｏｕｔ and the phase θ of the first quantized data ｏｕｔ１ The process of identifying each of these is a well-known technique, so a detailed explanation will be omitted. The frequency phase calculation unit 11 calculates the frequency f of the first quantized data. ｏｕｔ The frequency calculation unit 15 outputs information indicating the phase θ of the first quantized data. ｏｕｔ１ Information indicating this is output to the phase difference calculation unit 12.

[0032] The phase difference calculation unit 12 acquires the second quantization data from the quantizer 7, and acquires information indicating the phase θ of the first quantization data from the frequency phase calculation unit 11. ｏｕｔ１ For example, the phase difference calculation unit 12 converts the second quantization data into a signal in the frequency domain by performing FFT on the second quantization data. The phase difference calculation unit 12 determines the phase θ of the second quantization data from the frequency bin of the frequency component of the peak in the signal in the frequency domain. ｏｕｔ２ The process of determining the phase θ of the second quantization data from the frequency bin of the frequency component of the peak is a known technique, and thus detailed description thereof is omitted. The phase difference calculation unit 12 calculates the phase difference Δθ between the phase θ of the first quantization data and the phase θ of the second quantization data as shown in the following formula (1) (step ST2 in FIG. 4). Δθ = θ ｏｕｔ２ - θout1 (1) The phase difference calculation unit 12 outputs information indicating the phase difference Δθ to the phase difference correction unit 13. ｏｕｔ１ and the phase θ of the second quantization data ｏｕｔ２ (step ST2 in FIG. 4). Δθ = θ ｏｕｔ２ - θout1 (1) The phase difference calculation unit 12 outputs information indicating the phase difference Δθ to the phase difference correction unit 13.

[0033] In the calibration data storage unit 16, calibration data θ ｃａｌ (f ｏｕｔ ) and the phase difference Δθ ｃｌｋ are stored. FIG. 6 is an explanatory diagram showing an example of the calibration data θ ｃａｌ (f ｏｕｔ ) and the phase difference Δθ ｃｌｋ . In FIG. 6, the horizontal axis represents the frequency f ｏｕｔ of the first quantization data, and the vertical axis represents the phase difference Δθ between the phase θ ｏｕｔ１ of the first quantization data and the phase θ ｏｕｔ２ of the second quantization data. FIG. 6 shows the phase difference Δθ with respect to the frequency f ｏｕｔ of the first quantization data when a calibration signal in which the frequency f ｏｕｔ exists in the first Nyquist zone is given to the distributor 2 as a measurement signal. When the frequency f ｏｕｔ of the first quantization data is, for example, f １ ​​​ｃａｌ (f ｏｕｔ ) can be expressed as shown in equation (2) below.

[0034] As shown in Figure 7, the calibration data storage unit 16 stores calibration data θ corresponding to each of a plurality of different phase differences Δθ. ｃａｌ (f ｏｕｔ ) is stored. Figure 7 shows the calibration data θ for each phase difference Δθ. ｃａｌ (f ｏｕｔ ) and phase difference Δθ ｃｌｋ This is an explanatory diagram illustrating the concept.

[0035] Furthermore, Figure 6 shows the frequency f ｏｕｔ It exists in the secondary Nyquist zone, and the aliasing frequency is frequency f １ When a calibration signal with the same frequency as the first quantized data is supplied to the distributor 2 as the signal to be measured, the frequency f of the first quantized data is... ｏｕｔ The phase difference Δθ is shown. The frequency f of the first quantized data. ｏｕｔ However, for example f １ The phase difference Δθ in this case is Δθ ２ Furthermore, Figure 6 shows the phase difference Δθ. １ and phase difference Δθ ２ The difference between these two is the phase difference Δθ. ｃｌｋ This is represented by the phase difference Δθ. ｃｌｋ This corresponds to the sampling phase difference between quantizer 6 and quantizer 7. As shown in Figure 7, the calibration data storage unit 16 stores the phase difference Δθ corresponding to each of a plurality of different phase differences Δθ. ｃｌｋ It is remembered.

[0036] The phase difference calibration unit 13 acquires information indicating the phase difference Δθ from the phase difference calculation unit 12. The phase difference calibration unit 13 acquires calibration data θ corresponding to the phase difference Δθ from the calibration data storage unit 16. ｃａｌ (f ｏｕｔ ) is obtained. The phase difference Δθ is, for example, Δθ １ If so, Δθ １ Corresponding calibration data θ ｃａｌ (f ｏｕｔ ) １ The following is obtained, and the phase difference Δθ is, for example, Δθ ２ If so, Δθ２ Corresponding calibration data θ ｃａｌ (f ｏｕｔ ) ２ The following is obtained. The phase difference calibration unit 13 obtains calibration data θ as shown in the following equation (3). ｃａｌ (f ｏｕｔ The phase difference Δθ is calibrated according to (step ST3 in Figure 4). The phase difference calibration unit 13 then calibrates the phase difference Δθ after calibration. ｃａｌ Information indicating this is output to the loopback order calculation unit 14.

[0037]

[0038] The folding order calculation unit 14 receives the phase difference Δθ after calibration from the phase difference calibration unit 13. ｃａｌ Information indicating the following is obtained. The folding order calculation unit 14 calculates the phase difference Δθ corresponding to the phase difference Δθ. ｃｌｋ Information indicating this is obtained. The folding order calculation unit 14 calculates the phase difference Δθ as shown in the following equation (4). ｃａｌ Phase difference Δθ ｃｌｋ The Nyquist aliasing order Fo is calculated by dividing by (step ST4 in Figure 4). The aliasing order calculation unit 14 outputs the Nyquist aliasing order Fo to the frequency calculation unit 15.

[0039]

[0040] The frequency calculation unit 15 receives the frequency f of the first quantized data from the frequency phase calculation unit 11. ｏｕｔ Information indicating the frequency is obtained. The frequency calculation unit 15 obtains the Nyquist aliasing order Fo from the aliasing order calculation unit 14. The frequency f of the clock signal oscillated by the clock signal source 1 ｃｌｋ Information indicating this is stored, for example, in the internal memory of the frequency calculation unit 15. Alternatively, the frequency f ｃｌｋ Information indicating this is provided to the frequency calculation unit 15 from outside the frequency detection device 8, for example.

[0041] If the Nyquist aliasing order Fo is 0 or greater (in step ST5: YES in Figure 4), the frequency calculation unit 15 calculates the frequency f of the clock signal as shown in the following equation (5): the Nyquist aliasing order Fo and the frequency f of the clock signal. ｃｌｋThe frequency f of the first quantized data is obtained by multiplying the result of the first quantization. ｏｕｔ By adding this, the frequency f of the signal under measurement is obtained. ＲＦ The frequency calculation unit 15 calculates the frequency f of the clock signal, as shown in equation (6) below, if the Nyquist aliasing order Fo is negative (step ST5 in Figure 4: NO). ｃｌｋ From the result of multiplication, the frequency f of the first quantized data is obtained. ｏｕｔ By subtracting the frequency f of the signal under measurement, ＲＦ The frequency f of the signal under test is calculated (step ST7 in Figure 4). ＲＦ Information indicating this is provided, for example, to a signal processing device (not shown) or a display device (not shown).

[0042]

[0043] In the above embodiment 1, the frequency detection device 8 is configured to include a frequency-phase calculation unit 11 that calculates the frequency and phase of a first quantized data, which is a quantized signal of the signal to be measured, and a phase difference calculation unit 12 that calculates the phase of a second quantized data, which is data delayed compared to the first quantized data, and calculates the phase difference between the phase of the first quantized data and the phase of the second quantized data. The frequency detection device 8 also includes a phase difference calibration unit 13 that acquires calibration data corresponding to the phase difference calculated by the phase difference calculation unit 12 and calibrates the phase difference according to the calibration data, an aliasing order calculation unit 14 that calculates the Nyquist aliasing order of the first quantized data based on the phase difference after calibration by the phase difference calibration unit 13, and a frequency calculation unit 15 that calculates the frequency of the signal to be measured using the frequency calculated by the frequency-phase calculation unit 11 and the Nyquist aliasing order calculated by the aliasing order calculation unit 14.Therefore, the frequency detection device 8 can calculate the frequency of the signal to be measured without implementing two sample-and-hold circuits.

[0044] Embodiment 2. Embodiment 2 describes a frequency detection device 8 that includes a calibration data calculation unit 17 for calculating calibration data.

[0045] Figure 8 is a configuration diagram showing a frequency detection circuit including a frequency detection device 8 according to Embodiment 2. In Figure 8, the same reference numerals as in Figure 1 indicate the same or corresponding parts, so a detailed explanation is omitted. Figure 9 is a hardware configuration diagram showing the hardware of the frequency detection device 8 according to Embodiment 2. In Figure 9, the same reference numerals as in Figure 2 indicate the same or corresponding parts, so a detailed explanation is omitted. The frequency detection device 8 shown in Figure 8 includes a frequency phase calculation unit 11, a phase difference calculation unit 12, a phase difference calibration unit 13, an aliasing order calculation unit 14, a frequency calculation unit 15, a calibration data storage unit 16, and a calibration data calculation unit 17.

[0046] In the frequency detection circuit shown in Figure 8, a first calibration signal and an nth calibration signal are sequentially supplied to the distributor 2 before the signal to be measured is supplied to the distributor 2. n is an integer of 2 or greater. The first calibration signal is a calibration signal having a frequency in the first-order Nyquist region, and the nth calibration signal is a calibration signal having a frequency in the nth-order Nyquist region. The first calibration signal and the nth calibration signal are signals supplied to calculate calibration data to be stored in the calibration data storage unit 16.

[0047] The calibration data calculation unit 17 is implemented, for example, by the calibration data calculation circuit 27 shown in Figure 9. The calibration data calculation unit 17 calculates the phase difference calculated by the phase difference calculation unit 12 when, instead of the signal under measurement, the first calibration signal is provided to the distributor 2, thereby providing the first calibration quantized data, which is a signal obtained by quantizing the first calibration signal, to the frequency phase calculation unit 11, and when, instead of the second quantized data, the second calibration quantized data, which is data delayed compared to the first calibration quantized data, is provided to the phase difference calculation unit 12, the calibration data θ ｃａｌ (f ｏｕｔ ) is calculated as follows. Specifically, the calibration data calculation unit 17 calculates the frequency f from among M first calibration quantization data with different frequencies. ｏｕｔｍ The first calibration quantization data (m = 1, ..., M) is given to the frequency phase calculation unit 11, and among the M second calibration quantization data with different frequencies, frequency f ｏｕｔｍWhen the second calibration quantization data is provided to the phase difference calculation unit 12, the phase difference calculated by the phase difference calculation unit 12 is the calibration data θ ｃａｌ (f ｏｕｔ ) ｍ It is calculated as follows: M is an integer greater than or equal to 2.

[0048] The calibration data calculation unit 17 calculates the calibration data θ ｃａｌ (f ｏｕｔ ) ｍ In addition to calculating the above, the phase difference between the calibration signals, which is the difference between the first phase difference and the second phase difference, is calculated. The first phase difference is the phase difference between the phase of the first calibration quantized data and the phase of the data that is delayed compared to the first calibration quantized data. The second phase difference is the phase difference between the phase of the nth calibration quantized data, which is the signal in which the nth calibration signal has been quantized, and the phase of the data that is delayed compared to the nth calibration quantized data. The phase difference between the calibration signals is the phase difference between the phase of the first calibration signal and the phase of the nth calibration signal, that is, the phase difference Δθ, which is the difference between the first phase difference and the second phase difference. ｃｌｋｍ This corresponds to the following. Specifically, the calibration data calculation unit 17 calculates the frequency f of the M first calibration signals, which have different frequencies from each other. ｏｕｔｍ When a first calibration signal (m = 1, ..., M) is supplied to the distributor 2, the frequency phase calculation unit 11 obtains information indicating the phase of the first calibration quantization data. The calibration data calculation unit 17 selects from among the M nth calibration signals, each with a different frequency, the frequency f ｏｕｔｍ When the nth calibration signal (m=1, ..., M) is supplied to the distributor 2, the frequency phase calculation unit 11 obtains information indicating the phase of the nth calibration quantization data. Then, the calibration data calculation unit 17 calculates the frequency f ｏｕｔｍ Phase and frequency f of the first calibration quantization data ｏｕｔｍ The first phase difference is the phase difference between the phase of the data that is delayed compared to the first calibration quantization data, and the frequency f ｏｕｔｍ Phase and frequency f of the nth calibration quantization data ｏｕｔｍ The difference between the second phase difference, which is the phase difference between the phase of the data that is delayed compared to the nth calibration quantization data, and the frequency f is defined as the difference between the second phase difference and the nth calibration quantization data. ｏｕｔｍ Phase difference Δθ ｃｌｋｍThe calibration data calculation unit 17 calculates the calibration data θ. ｃａｌ (f ｏｕｔ ) ｍ (m = 1, ..., M) and phase difference Δθ ｃｌｋｍ Each of these is output to the calibration data storage unit 16.

[0049] In Figure 8, it is assumed that the frequency detection device 8's components—the frequency phase calculation unit 11, the phase difference calculation unit 12, the phase difference calibration unit 13, the aliasing order calculation unit 14, the frequency calculation unit 15, the calibration data storage unit 16, and the calibration data calculation unit 17—are each implemented by dedicated hardware as shown in Figure 9. Specifically, it is assumed that the frequency detection device 8 is implemented by a frequency phase calculation circuit 21, a phase difference calculation circuit 22, a phase difference calibration circuit 23, an aliasing order calculation circuit 24, a frequency calculation circuit 25, a calibration data storage circuit 26, and a calibration data calculation circuit 27. Each of the frequency phase calculation circuit 21, the phase difference calculation circuit 22, the phase difference calibration circuit 23, the aliasing order calculation circuit 24, the frequency calculation circuit 25, and the calibration data calculation circuit 27 can be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof.

[0050] The components of the frequency detection device 8 are not limited to those implemented by dedicated hardware; the frequency detection device 8 may also be implemented by software, firmware, or a combination of software and firmware. When the frequency detection device 8 is implemented by software or firmware, the calibration data storage unit 16 is configured on the memory 31 shown in Figure 3. Programs for causing a computer to execute the respective processing procedures in the frequency phase calculation unit 11, phase difference calculation unit 12, phase difference calibration unit 13, aliasing order calculation unit 14, frequency calculation unit 15, and calibration data calculation unit 17 are stored in the memory 31. Then, the processor 32 shown in Figure 3 executes the programs stored in the memory 31.

[0051] Furthermore, Figure 9 shows an example in which each component of the frequency detection device 8 is implemented by dedicated hardware, while Figure 3 shows an example in which the frequency detection device 8 is implemented by software or firmware. However, this is merely one example, and some components of the frequency detection device 8 may be implemented by dedicated hardware, while the remaining components may be implemented by software or firmware.

[0052] Next, the operation of the frequency detection circuit shown in Figure 8 will be explained. The frequency f of the signal under measurement ＲＦ The process for detecting the frequency is the same as that of the frequency detection circuit shown in Figure 1. The frequency detection circuit shown in Figure 8 differs from the frequency detection circuit shown in Figure 1 in that it includes a process for calculating calibration data, etc.

[0053] The frequency detection device 8 detects the frequency f of the signal under measurement. ＲＦ Before detecting the frequency f, in order to calculate calibration data, etc., first, M first calibration signals with different frequencies are sequentially supplied to the distributor 2. ｏｕｔｍ When a first calibration signal (m=1, ..., M) is given, the frequency f ｏｕｔｍ The first calibration signal is split into two. The splitter 2 outputs one of the split first calibration signals to the delay circuit 4, and outputs the other split first calibration signal to the delay circuit 5.

[0054] The delay circuit 4 delays one of the first calibration signals after distribution by a delay time τ １ The first calibration signal is delayed by a certain amount of time, and the delayed first calibration signal is output to the quantizer 6. The delay circuit 5 delays the other first calibration signal after distribution by a delay time τ. ２ The signal is delayed by a certain amount, and the first calibration signal after the delay is output to the quantizer 7.

[0055] The quantizer 6 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the first calibration signal after delay by the delay circuit 4. The quantizer 6 outputs the first calibration quantization data, which is the first calibration signal after quantization, to the frequency phase calculation unit 11. The quantizer 7 uses the frequency f output from the clock signal source 1. ｃｌｋThe clock signal is used to quantize the first calibration signal after the delay by the delay circuit 5. The quantizer 7 outputs the first' calibration quantization data, which is the first calibration signal after quantization, to the phase difference calculation unit 12.

[0056] The frequency-phase calculation unit 11 acquires first calibration quantization data from the quantizer 6. The frequency-phase calculation unit 11 converts the first calibration quantization data into a frequency domain signal, for example, by performing an FFT on the first calibration quantization data. The frequency-phase calculation unit 11 calculates the phase θ of the first calibration quantization data from the frequency bins of the frequency components of the peaks in the frequency domain signal. ｏｕｔｍ The values ​​(m = 1, ..., M) are determined. The frequency phase calculation unit 11 calculates the phase θ of the first calibration quantization data. ｏｕｔｍ Information indicating this is output to the phase difference calculation unit 12 and the calibration data calculation unit 17, respectively.

[0057] The phase difference calculation unit 12 acquires the first' calibration quantization data from the quantizer 7, and the frequency phase calculation unit 11 calculates the phase θ of the first calibration quantization data. ｏｕｔｍ Information indicating (m = 1, ..., M) is obtained. The phase difference calculation unit 12 converts the first' calibration quantization data into a frequency domain signal by, for example, performing an FFT on the first' calibration quantization data. The phase difference calculation unit 12 obtains the phase θ of the first' calibration quantization data from the frequency bins of the frequency components of the peaks in the frequency domain signal. ｏｕｔｍ The phase difference calculation unit 12 determines the phase θ of the first calibration quantization data, as shown in equation (7) below. ｏｕｔｍ and the phase θ of the 1' calibration quantization data ｏｕｔｍ The first phase difference Δθ is the phase difference with ' １，ｍ Calculate Δθ. １，ｍ = θ ｏｕｔｍ '-θoutm (7) The phase difference calculation unit 12 calculates the first phase difference Δθ １，ｍ The calibration data calculation unit 17 outputs information indicating this.

[0058] Next, M nth calibration signals with different frequencies are sequentially supplied to the distributor 2. The distributor 2 receives frequency f ｏｕｔｍGiven the nth calibration signal (m=1, ..., M), the frequency f ｏｕｔｍ The nth calibration signal is split into two. Distributor 2 outputs one of the nth calibration signals after splitting to delay circuit 4, and outputs the other nth calibration signal after splitting to delay circuit 5.

[0059] The delay circuit 4 delays one of the nth calibration signals after distribution by time τ １ The nth calibration signal is delayed by a certain amount of time, and the nth calibration signal after the delay is output to the quantizer 6. The delay circuit 5 delays the other nth calibration signal after distribution by a delay time τ. ２ The signal is delayed by a certain amount, and the nth calibration signal after the delay is output to the quantizer 7. The quantizer 6 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the nth calibration signal after delay by the delay circuit 4. The quantizer 6 outputs the nth calibration quantized data, which is the nth calibration signal after quantization, to the frequency phase calculation unit 11. The quantizer 7 uses the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is used to quantize the nth calibration signal after the delay circuit 5. The quantizer 7 outputs the n'th calibration quantization data, which is the nth calibration signal after quantization, to the phase difference calculation unit 12.

[0060] The frequency-phase calculation unit 11 acquires the nth calibration quantization data from the quantizer 6. The frequency-phase calculation unit 11 converts the nth calibration quantization data into a frequency domain signal by, for example, performing an FFT on the nth calibration quantization data. The frequency-phase calculation unit 11 calculates the phase θ of the nth calibration quantization data from the frequency bins of the peak frequency components in the frequency domain signal. ｏｕｔｍ The values ​​(m = 1, ..., M) are determined. The frequency phase calculation unit 11 determines the phase θ of the nth calibration quantization data. ｏｕｔｍ Information indicating this is output to the phase difference calculation unit 12 and the calibration data calculation unit 17, respectively.

[0061] The phase difference calculation unit 12 obtains the n'th calibration quantization data from the quantizer 7, and the frequency phase calculation unit 11 calculates the phase θ of the nth calibration quantization data. ｏｕｔｍInformation indicating (m = 1, ..., M) is obtained. The phase difference calculation unit 12 converts the n'th calibration quantization data into a frequency domain signal by, for example, performing an FFT on the n'th calibration quantization data. The phase difference calculation unit 12 calculates the phase θ of the n'th calibration quantization data from the frequency bins of the peak frequency components in the frequency domain signal. ｏｕｔｍ The phase difference calculation unit 12 determines the phase θ of the nth calibration quantization data, as shown in equation (8) below. ｏｕｔｍ and the phase θ of the n'th calibration quantization data ｏｕｔｍ The second phase difference Δθ is the phase difference with ' ２，ｍ Calculate Δθ. ２，ｍ = θ ｏｕｔｍ '-θoutm (8) The phase difference calculation unit 12 calculates the second phase difference Δθ ２，ｍ The calibration data calculation unit 17 outputs information indicating this.

[0062] The calibration data calculation unit 17 receives the first phase difference Δθ from the phase difference calculation unit 12. １，ｍ Information indicating and the second phase difference Δθ ２，ｍ Information indicating the above is obtained. The calibration data calculation unit 17 calculates the first phase difference Δθ as shown in the following equation (9). １，ｍ and the second phase difference Δθ ２，ｍ The difference between these is the phase difference Δθ ｃｌｋｍ It is calculated as follows: Δθ ｃｌｋｍ = Δθ １，ｍ -Δθ2,m (9)

[0063] The calibration data calculation unit 17 calculates the frequency f from among M first calibration quantization data with different frequencies. ｏｕｔｍ The first calibration quantization data (m = 1, ..., M) is given to the frequency phase calculation unit 11, and among the M second calibration quantization data with different frequencies, frequency f ｏｕｔｍ When the second calibration quantization data is provided to the phase difference calculation unit 12, the phase difference calculated by the phase difference calculation unit 12 is the calibration data θ ｃａｌ (f ｏｕｔ ) ｍ It is calculated as follows.

[0064] The calibration data calculation unit 17 calculates the calibration data θｃａｌ (f ｏｕｔ ) ｍ Information indicating (m=1, ..., M) and the phase difference Δθ ｃｌｋｍ Information indicating the phase difference Δθ is output to the calibration data storage unit 16. ｍ Calibration data θ corresponding to (m = 1, ..., M) ｃａｌ (f ｏｕｔ ) ｍ And, the phase difference Δθ ｍ The corresponding phase difference Δθ ｃｌｋｍ This is remembered.

[0065] In the above embodiment 2, the frequency detection device 8 is configured such that when a first calibration quantized data, which is a signal obtained by quantizing a first calibration signal having a frequency in the first-order Nyquist region instead of the first quantized data, is provided to the frequency phase calculation unit 11, and when a second calibration quantized data, which is data delayed more than the first calibration quantized data, is provided to the phase difference calculation unit 12 instead of the second quantized data, the calibration data calculation unit 17 calculates the phase difference calculated by the phase difference calculation unit 12 as calibration data, the frequency detection device 8 is configured such that when the first quantized data is provided to the frequency phase calculation unit 11 and the second quantized data is provided to the phase difference calculation unit 12, the phase difference calibration unit 13 calibrates the phase difference calculated by the phase difference calculation unit 12 according to the calibration data calculated by the calibration data calculation unit 17.

[0066] In Embodiment 2, the frequency detection device 8 is configured such that, in addition to calculating calibration data, the calibration data calculation unit 17 calculates the difference between a first phase difference, which is the phase difference between the phase of the first calibration quantization data and the phase of data delayed more than the first calibration quantization data, and a second phase difference, which is the phase difference between the phase of the nth calibration quantization data and the phase of data delayed more than the nth calibration quantization data, as the phase difference between the phase of the first calibration signal and the phase of the nth calibration signal. Therefore, the frequency detection device 8 can calculate the frequency of the signal under test without implementing two sample-and-hold circuits, and can also calculate the phase difference between the phase of the first calibration quantization data and the phase of the nth calibration quantization data before calculating the frequency of the signal under test.

[0067] In the frequency detection device 8 shown in Figure 8, the phase difference calculation unit 12 calculates the frequency f ｏｕｔｍ Phase θ of the first calibration quantized data (m=1, ..., M) ｏｕｔｍ and frequency f ｏｕｔｍ Phase θ of the first' calibration quantization data ｏｕｔｍ The first phase difference Δθ is the phase difference with ' １，ｍ The phase difference calculation unit 12 calculates the frequency f ｏｕｔｍ The phase θ of the nth calibration quantization data ｏｕｔｍ and frequency f ｏｕｔｍ Phase θ of the n'th calibration quantization data ｏｕｔｍ The second phase difference Δθ is the phase difference with ' ２，ｍ The calibration data calculation unit 17 calculates the frequency f ｏｕｔｍ The first phase difference Δθ of (m = 1, ..., M) １，ｍ By linear interpolating, the frequency f ｏｕｔｍ The first phase difference Δθ with respect to frequencies different from (m = 1, ..., M) １，ｍ The calibration data calculation unit 17 calculates the frequency f. ｏｕｔｍ The second phase difference Δθ of (m=1, ..., M) ２，ｍ By linear interpolating, the frequency f ｏｕｔｍ (m=1, ..., M) and the second phase difference Δθ related to different frequencies ２，ｍThe calibration data calculation unit 17 then calculates the frequency f ｏｕｔｍ The first phase difference Δθ with respect to frequencies different from (m = 1, ..., M) １，ｍ and frequency f ｏｕｔｍ (m=1, ..., M) and the second phase difference Δθ related to different frequencies ２，ｍ The difference between this and the frequency f ｏｕｔｍ The calculation may also be performed as the phase difference between calibration signals with different frequencies (m = 1, ..., M).

[0068] frequency f ｏｕｔｍ The phase difference between the phase of the first calibration quantization data having a different frequency and the phase of the first' calibration quantization data is, for example, as shown in Figure 10, frequency f ｏｕｔｍ and frequency f ｏｕｔｍ＋１ This is the phase difference corresponding to the frequency between [the specified frequency] and [the specified frequency]. ｏｕｔｍ The phase difference between the phase of the nth calibration quantization data having a different frequency and the phase of the n'th calibration quantization data is, for example, as shown in Figure 11, frequency f ｏｕｔｍ and frequency f ｏｕｔｍ＋１ This is the phase difference corresponding to the frequency between [the specified point] and [the specified point]. Figure 10 shows the frequency f. ｏｕｔｍ The first phase difference Δθ of (m = 1, ..., M) １，ｍ This is an explanatory diagram showing the linear interpolation result for frequency f. ｏｕｔｍ The second phase difference Δθ of (m=1, ..., M) ２，ｍ This is an explanatory diagram showing the linear interpolation results. In Figures 10 and 11, the horizontal axis represents the frequency of the calibration signal, and the vertical axis represents the phase difference of the calibration signal.

[0069] Embodiment 3. The frequency detection circuits according to Embodiments 1 and 2 include a quantization unit 3 in which delay circuits 4 and 5 are implemented before the quantizers 6 and 7. Embodiment 3 describes a frequency detection circuit that includes a quantization unit 3 in which the delay circuits 4 and 5 are not implemented before the quantizers 6 and 7, but a delay circuit 9 is implemented between the clock signal source 1 and the quantizer 7.

[0070] Figure 12 is a configuration diagram showing a frequency detection circuit including a frequency detection device 8 according to Embodiment 3. In Figure 12, the same reference numerals as in Figures 1 and 8 indicate the same or corresponding parts, so a detailed explanation is omitted. The delay circuit 9 receives the frequency f output from the clock signal source 1. ｃｌｋ The clock signal is delayed by a delay time τ, and the delayed clock signal is output to the quantizer 7. The second quantized data output from the quantizer 7 is delayed by a delay time τ compared to the first quantized data output from the quantizer 6. The frequency detection device 8 shown in Figure 12 operates in the same manner as the frequency detection device 8 shown in Figure 1.

[0071] The frequency detection circuit shown in Figure 12 is an example in which the delay circuit 9 is applied to the frequency detection circuit shown in Figure 1. However, this is merely one example, and the delay circuit 9 may also be applied to the frequency detection circuit shown in Figure 8.

[0072] Furthermore, this disclosure allows for free combination of each embodiment, modification of any component in each embodiment, or omission of any component in each embodiment.

[0073] This disclosure is suitable for use in, for example, a frequency detection device for detecting the frequency of a signal under test, a frequency detection method for detecting the frequency of a signal under test, and a frequency detection circuit for detecting the frequency of a signal under test, because it can calculate the frequency of a signal under test without implementing two sample-and-hold circuits.

[0074] 1 Clock signal source, 2 Distributor, 3 Quantization unit, 4, 5, 9 Delay circuits, 6, 7 Quantizer, 8 Frequency detection device, 11 Frequency phase calculation unit, 12 Phase difference calculation unit, 13 Phase difference calibration unit, 14 Alias ​​order calculation unit, 15 Frequency calculation unit, 16 Calibration data storage unit, 17 Calibration data calculation unit, 21 Frequency phase calculation circuit, 22 Phase difference calculation circuit, 23 Phase difference calibration circuit, 24 Alias ​​order calculation circuit, 25 Frequency calculation circuit, 26 Calibration data storage circuit, 27 Calibration data calculation circuit, 31 Memory, 32 Processor.

Claims

1. A frequency detection device comprising: a frequency-phase calculation unit that calculates the frequency and phase of a first quantized data, which is a quantized signal of the signal to be measured; a phase difference calculation unit that calculates the phase of a second quantized data, which is data delayed compared to the first quantized data, and calculates the phase difference between the phase of the first quantized data and the phase of the second quantized data; a phase difference calibration unit that acquires calibration data corresponding to the phase difference calculated by the phase difference calculation unit and calibrates the phase difference according to the calibration data; an aliasing order calculation unit that calculates the Nyquist aliasing order of the first quantized data based on the phase difference after calibration by the phase difference calibration unit; and a frequency calculation unit that calculates the frequency of the signal to be measured using the frequency calculated by the frequency-phase calculation unit and the Nyquist aliasing order calculated by the aliasing order calculation unit.

2. The frequency detection device according to claim 1, wherein, when a first calibration quantized data is provided to the frequency phase calculation unit, which is a signal obtained by quantizing a first calibration signal having a frequency in the first-order Nyquist region instead of the first quantized data, and when a second calibration quantized data is provided to the phase difference calculation unit, which is data delayed more than the first calibration quantized data instead of the second quantized data, the device comprises a calibration data calculation unit that calculates the phase difference calculated by the phase difference calculation unit as the calibration data, and when the first quantized data is provided to the frequency phase calculation unit and the second quantized data is provided to the phase difference calculation unit, the phase difference calibration unit calibrates the phase difference calculated by the phase difference calculation unit according to the calibration data calculated by the calibration data calculation unit.

3. The frequency detection device according to claim 2, characterized in that when each of a plurality of first calibration quantization data sets having different frequencies is provided to the frequency phase calculation unit as the first calibration quantization data, and each of a plurality of second calibration quantization data sets having different frequencies is provided to the phase difference calculation unit as the second calibration quantization data, the calibration data calculation unit calculates the respective phase differences calculated by the phase difference calculation unit as the calibration data.

4. The frequency detection device according to claim 2 or 3, characterized in that, in addition to calculating the calibration data, the calibration data calculation unit calculates the difference between a first phase difference, which is the phase difference between the phase of the first calibration quantized data and the phase of data that is delayed compared to the first calibration quantized data, and a second phase difference, which is the phase difference between the phase of the nth calibration quantized data, which is a signal in which the nth calibration signal having a frequency in the nth order Nyquist region is quantized, and the phase of data that is delayed compared to the nth calibration quantized data, as the phase difference between the phase of the first calibration signal and the phase of the nth calibration signal.

5. The frequency detection device according to claim 4, characterized in that the calibration data calculation unit acquires the phases of a plurality of first calibration quantization data with different frequencies as the phase of the first calibration quantization data, acquires the phases of a plurality of nth calibration quantization data with different frequencies as the phase of the nth calibration quantization data, calculates the difference between a first phase difference, which is the phase difference between the phase of the first calibration quantization data having each frequency and the phase of data that is delayed compared to the first calibration quantization data having each frequency, and a second phase difference, which is the phase difference between the phase of the nth calibration quantization data having each frequency and the phase of data that is delayed compared to the nth calibration quantization data having each frequency, as the phase difference between calibration signals for each frequency, and the aliasing order calculation unit calculates the Nyquist aliasing order of the first quantization data using the phase difference after calibration by the phase difference calibration unit and the phase difference between calibration signals corresponding to the frequency calculated by the frequency phase calculation unit among the plurality of phase differences between calibration signals for each frequency calculated by the calibration data calculation unit.

6. The frequency detection device according to claim 5, characterized in that the calibration data calculation unit calculates a first phase difference, which is the phase difference between the phase of a first calibration quantization data having a different frequency and the phase of data having a different frequency and that is delayed compared to the first calibration quantization data, by linearly interpolating the phase difference between the phase of a first calibration quantization data having a different frequency and the phase of data having a different frequency and that is delayed compared to the first calibration quantization data, by linearly interpolating the phase difference between the phase of an nth calibration quantization data having a different frequency and the phase of data having a different frequency and that is delayed compared to the nth calibration quantization data, by linearly interpolating the phase difference between the phase of an nth calibration quantization data having a different frequency and that is delayed compared to the nth calibration quantization data, and calculates the difference between the first phase difference relating to a different frequency and the second phase difference relating to a different frequency as the phase difference between calibration signals relating to a different frequency.

7. A frequency detection method comprising: a frequency-phase calculation unit calculating the frequency and phase of a first quantized data, which is a quantized signal of the signal to be measured; a phase difference calculation unit calculating the phase of a second quantized data, which is data delayed compared to the first quantized data, and calculating the phase difference between the phase of the first quantized data and the phase of the second quantized data; a phase difference calibration unit acquiring calibration data corresponding to the phase difference calculated by the phase difference calculation unit and calibrating the phase difference according to the calibration data; an aliasing order calculation unit calculating the Nyquist aliasing order of the first quantized data based on the phase difference after calibration by the phase difference calibration unit; and a frequency calculation unit calculating the frequency of the signal to be measured using the frequency calculated by the frequency-phase calculation unit and the Nyquist aliasing order calculated by the aliasing order calculation unit.

8. A frequency detection circuit comprising: a quantization unit that quantizes a signal to be measured and outputs a first quantized data which is the quantized signal to be measured and a second quantized data which is delayed compared to the first quantized data; a frequency-phase calculation unit that calculates the frequency and the phase of the first quantized data output from the quantization unit; a phase difference calculation unit that calculates the phase of the second quantized data output from the quantization unit and calculates the phase difference between the phase of the first quantized data and the phase of the second quantized data; a phase difference calibration unit that acquires calibration data corresponding to the phase difference calculated by the phase difference calculation unit and calibrates the phase difference according to the calibration data; an aliasing order calculation unit that calculates the Nyquist aliasing order of the first quantized data based on the phase difference after calibration by the phase difference calibration unit; and a frequency calculation unit that calculates the frequency of the signal to be measured using the frequency calculated by the frequency-phase calculation unit and the Nyquist aliasing order calculated by the aliasing order calculation unit.

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