Patent Application
20250035742
The disclosure relates to an automatic tuning device, a magnetron radar, an automatic tuning method, and a recording medium.
Conventionally, in magnetron radars, a tuning process is performed to control the frequency of a carrier signal provided to a mixer, so that the output signal of the mixer, which down-converts a reception wave, is at a particular frequency.
For example, the radar receiver amplifies a reflected radar wave that is received, mixes the amplified wave with a local frequency signal output from a local oscillator to generate an intermediate frequency signal, and performs a particular reception process based on the intermediate frequency signal. In the radar receiver, the local oscillator is disposed in the same temperature environment as a microwave oscillator of a radar transmitter and has substantially the same temperature-oscillation frequency property as the microwave oscillator.
Beyond the conventional technology, a technology that enables more suitable control of the frequency of a carrier signal provided to a mixer in a tuning process is desired.
The disclosure provides an automatic tuning device, a magnetron radar, an automatic tuning method, and an automatic tuning program that can more suitably control the frequency of a carrier signal provided to a mixer in a tuning process.
An automatic tuning device according to an aspect of the disclosure is mounted on a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning device includes processing circuitry configured to: output a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; acquire a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; set a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; calculate an index value based on a scanning result of a first range including therein the first level in a second period; and determine the tuning control voltage output by the output unit based on a comparison result between the index value and the reference value.
According to an embodiment of the disclosure, the processing circuitry is further configured to: detect the first level based on a scanning result of a second range wider than the first range in the first period.
According to an embodiment of the disclosure, the processing circuitry is configured to: set the reference value based on the tuning indication voltage in the particular range, and calculate the index value based on the tuning indication voltage of the first range.
According to an embodiment of the disclosure, the processing circuitry is configured to: calculate multiple index values by scanning with a width same as the particular range, and determine the tuning control voltage in correspondence with a scanning position at which the index value equal to or more than the reference value is calculated.
According to an embodiment of the disclosure, the processing circuitry is configured to: set the reference value based on an accumulated value of the tuning indication voltage of the particular range, and calculate the index value based on the accumulated value of the tuning indication voltage.
According to an embodiment of the disclosure, the processing circuitry is configured to: set, as the reference value, a value obtained by multiplying the accumulated value by a particular value less than 1.
According to an embodiment of the disclosure, the particular range is a half-width of a peak of a maximum of the tuning indication voltage, and the processing circuitry is configured to calculate, as the index value, a half-width of a peak present in the first range.
An automatic tuning method according to an aspect of the disclosure is an automatic tuning method for a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning method includes: outputting a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; generating a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; setting a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; calculating an index value based on a scanning result of a first range including therein the first level in a second period; and determining the tuning control voltage output based on a comparison result between the index value and the reference value.
A non-transient computer-readable recording medium according to an aspect of the disclosure records an automatic tuning program for a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning program causes a computer to execute: a process of outputting a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; a process of generating a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; a process of setting a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; a process of calculating an index value based on a scanning result of a first range including therein the first level in a second period; and a process of determining the tuning control voltage output based on a comparison result between the index value and the reference value.
The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and processes that are consistent with the subject matter as claimed herein.
(1) In order to solve the issue, an automatic tuning device according to an aspect of the disclosure is an automatic tuning device mounted on a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning device includes: an output unit, outputting a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; an acquisition unit, acquiring a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; a setting unit, setting a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; a calculation unit, calculating an index value based on a scanning result of a first range including therein the first level in a second period; and a determination unit, determining the tuning control voltage output by the output unit based on a comparison result between the index value and the reference value.
In this way, with the configuration of determining the output level of the tuning control voltage based on the comparison result between the index value and the reference value, it is possible to determine the tuning control voltage output by the output unit by considering the comparison result between the index value based on the scanning result of the first range in the second period and the reference value based on the tuning indication voltage in the first period. Therefore, in the case where the tuning point during the second period transitions from the tuning point during the first period due to the temperature dependence of the magnetron, it is possible to recognize the transition of the tuning point based on the comparison result between the index value and the reference value and determine a more suitable tuning control voltage level for tuning by considering the transition of the tuning point. As a result, it is possible to more suitably control the frequency of the carrier signal provided to the mixer in the tuning process.
(2) According to (1), the automatic tuning device may further include a detection unit detecting the first level based on a scanning result of a second range wider than the first range in the first period.
With such configuration, compared to the time required for the process of detecting the first level in the first period, it is possible to perform the calculation of the index value and the determination of the tuning control voltage level in a shorter time in the second period.
(3) According to (2), the setting unit may set the reference value based on the tuning indication voltage in the particular range, and the calculation unit may calculate the index value based on the tuning indication voltage of the first range.
With such configuration, it is possible to calculate the reference value and the index value based on the tuning indication voltage of each range.
(4) According to (1), the calculation unit may calculate multiple index values by scanning with a width same as the particular range, and the determination unit may determine the tuning control voltage in correspondence with a scanning position at which the index value equal to or more than the reference value is calculated.
With such configuration, it is possible to determine the output level based on the scanning result of the level of the tuning control voltage in the scanning range according to the magnitude relationship between the index value and the reference value. Therefore, in a suitable scanning range corresponding to the degree of transition from the tuning point in the first period, it is possible to more reliably detect the tuning point in the second period and determine as the output level the detected tuning point.
(5) According to any one of (1) to (4), the setting unit may set the reference value based on an accumulated value of the tuning indication voltage of the particular range, and the calculation unit may calculate the index value based on the accumulated value of the tuning indication voltage.
With such configuration, by using the reference value based on the accumulated value and the index value based on the accumulated value, it is possible to more accurately recognize the transition of the tuning point in the second period from the tuning point in the first period.
(6) According to (5), the setting unit may set, as the reference value, a value obtained by multiplying the accumulated value by a particular value less than 1.
With such configuration, it is possible to flexibly set a threshold related to the degree of transition of the tuning point in the second period from the tuning point in the first period in accordance with the particular value by which the accumulated value is multiplied.
(7) According to (1), the particular range may be a half-width of a peak of a maximum of the tuning indication voltage, and the calculation unit may calculate, as the index value, a half-width of a peak present in the first range.
With such configuration, it is possible to calculate the index value with a simple process.
(8) In order to solve the issue, a magnetron radar according to an aspect of the disclosure includes the automatic tuning device according to any one of (1) to (7).
With such configuration, it is possible to realize a magnetron radar in which a more accurate tuning process is performed.
(9) In order to solve the issue, an automatic tuning method according to an aspect of the disclosure is an automatic tuning method for a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning method includes: outputting a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; generating a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; setting a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; calculating an index value based on a scanning result of a first range including therein the first level in a second period; and determining the tuning control voltage output based on a comparison result between the index value and the reference value.
In this way, with the method of determining the output level of the tuning control voltage based on the comparison result between the index value and the reference value, it is possible to determine the tuning control voltage output by the output unit by considering the comparison result between the index value based on the scanning result of the first range in the second period and the reference value based on the tuning indication voltage in the first period. Therefore, in the case where the tuning point during the second period transitions from the tuning point during the first period due to the temperature dependence of the magnetron, it is possible to recognize the transition of the tuning point based on the comparison result between the index value and the reference value and determine a more suitable tuning control voltage level for tuning by considering the transition of the tuning point. As a result, it is possible to more suitably control the frequency of the carrier signal provided to the mixer in the tuning process.
(9) In order to solve the issue, an automatic tuning program according to an aspect of the disclosure is an automatic tuning program for a magnetron radar including a mixer that down-converts a reception wave. The automatic tuning program causes a computer to execute: a process of outputting a tuning control voltage for adjusting a frequency of a carrier signal provided to the mixer; a process of generating a tuning indication voltage indicating an intensity of a component of a particular frequency in an output signal of the mixer; a process of setting a reference value based on a particular range including therein a first level that is the tuning control voltage corresponding to a maximum of the tuning indication voltage in a first period; a process of calculating an index value based on a scanning result of a first range including therein the first level in a second period; and a process of determining the tuning control voltage output based on a comparison result between the index value and the reference value.
In this way, with the method of determining the output level of the tuning control voltage based on the comparison result between the index value and the reference value, it is possible to determine the tuning control voltage output by the output unit by considering the comparison result between the index value based on the scanning result of the first range in the second period and the reference value based on the tuning indication voltage in the first period. Therefore, in the case where the tuning point during the second period transitions from the tuning point during the first period due to the temperature dependence of the magnetron, it is possible to recognize the transition of the tuning point based on the comparison result between the index value and the reference value and determine a more suitable tuning control voltage level for tuning by considering the transition of the tuning point. As a result, it is possible to more suitably control the frequency of the carrier signal provided to the mixer in the tuning process.
According to the disclosure, in the tuning process, it is possible to more suitably control the frequency of the carrier signal provided to the mixer.
The following describes embodiments of the disclosure using the drawings. In the drawings, the same or equivalent parts are given the same reference numerals, and their descriptions are not repeated. Additionally, at least some of the embodiments described below may be combined arbitrarily.
The magnetron radar 301 performs a detection process of detecting the presence or absence of a target in a detection target area, which is a region to be monitored, and a distance between the magnetron radar 301 and the target. More specifically, in the detection process, the magnetron radar 301 transmits a transmission wave to the detection target area and receives a reception wave including a reflection wave from the detection target area. Then, based on the reception wave, the magnetron radar 301 performs a process of displaying an echo image on the display processing unit 202. The echo image indicates the presence or absence of the target in the detection target area and the distance between the magnetron radar 301 and the target.
For example, in the magnetron radar 301, it is possible to change the setting of the detection range that indicates the size of the detection target area. The magnetron radar 301 performs a process of displaying on the display processing unit 202 the echo image for the detection target area corresponding to the detection range set by the user.
The radar unit 201 includes a transmission control unit 21, a transmission unit 22, a circulator 23, an antenna 24, a reception unit 25, a mixer 26, a local oscillator 27, band pass filters (BPFs) 28A, 28B, a signal processing unit 29, and a generation unit 30.
The transmission control unit 21 outputs a pulse-like transmission trigger to the transmission unit 22. More specifically, the transmission control unit 21 receives the setting of the detection range from the user and outputs the transmission trigger with a pulse width PW corresponding to the received detection range to the transmission unit 22.
The transmission unit 22 generates a transmission wave of a radio frequency (RF) band based on the transmission trigger received from the transmission control unit 21, and outputs the generated transmission wave via the circulator 23 and the antenna 24. A magnetron is used for generating the transmission wave in the transmission unit 22. The transmission unit 22 generates the transmission wave with a frequency unique to the magnetron. As an example, the transmission unit 22 generates, as the transmission wave, a sine wave of 9410 MHz during a period corresponding to the pulse width PW of the transmission trigger received from the transmission control unit 21. The transmission unit 22 may also be configured to generate a sine wave of 3050 MHz, which is in an S-band, as the transmission wave. Hereinafter, the frequency of the transmission wave output by the transmission unit 22 is also referred to as a transmission frequency ft.
The reception unit 25 receives, via the antenna 24 and the circulator 23, a signal of the RF band including a reflection wave that is a transmission wave transmitted from the antenna 24 and reflected by the target, etc. The reception unit 25 outputs the received signal, which is the reception wave, to the mixer 26.
The automatic tuning unit 101 outputs an analog tuning control voltage Vcont to the local oscillator 27. The tuning control voltage Vcont is provided for adjusting the frequency of a local oscillator (LO) signal to be provided to the mixer 26. The LO signal is an example of a carrier signal.
The local oscillator 27 receives the tuning control voltage Vcont from the automatic tuning unit 101 and outputs an LO signal with a frequency corresponding to the level of the received tuning control voltage Vcont to the mixer 26. For example, the local oscillator 27 outputs an LO signal of 9470 MHz to the mixer 26. For example, in the case where the transmission unit 22 generates a sine wave of 3050 MHz as the transmission wave, the local oscillator 27 outputs an LO signal of 3110 MHz to the mixer 26. The frequency of the LO signal output by the local oscillator 27 is not limited to 3050 MHz or 9470 MHz, but can be any frequency corresponding to the frequency of the transmission wave generated by the transmission unit 22.
The mixer 26 down-converts the reception wave received from the reception unit 25. More specifically, the mixer 26 converts the reception wave of 9410 MHz received from the reception unit 25 into an intermediate frequency (IF) signal of 60 MHz by down-converting the reception wave using the LO signal of 9470 MHz received from the local oscillator 27, and outputs the converted IF signal to the BPFs 28A, 28B. The frequency of the IF signal output by the mixer 26 is not limited to 60 MHz, but can be any frequency corresponding to the frequency of the reception wave and the frequency of the LO signal.
The BPF 28A attenuates, among the frequency components of the IF signal received from the mixer 26, a component outside a particular pass band. A center frequency Fc1 of the pass band of the BPF 28A is, for example, 60 MHz. The center frequency Fc1 is not limited to 60 MHz, but can be any frequency corresponding to the IF signal output by the mixer 26. The BPF 28B attenuates, among the frequency components of the IF signal received
from the mixer 26, a component outside a particular pass band. For example, a center frequency Fc2 of the pass band of the BPF 28B is 60 MHZ, and the pass band of the BPF 28B is the same as that of the BPF 28A. The bandwidth of the BPF 28B and the bandwidth of the BPF 28A may also be different from each other. The center frequency Fc2 is not limited to 60 MHz, but can be any frequency corresponding to the IF signal output by the mixer 26.
The signal processing unit 29 amplifies the signal that has passed through the BPF 28A, converts the amplified signal into a digital signal by sampling at a particular sampling frequency, and generates echo data based on the converted digital signal. The signal processing unit 29 outputs the generated echo data to the display processing unit 202.
The display processing unit 202 performs a process of displaying an echo image of the detection target area on a display device based on the echo data received from the radar unit 201.
The generation unit 30 generates a tuning indication voltage Vind indicating the intensity of the frequency component of 60 MHz in the IF signal output from the mixer 26, based on the signal that has passed through the BPF 28B. The generation unit 30 may also be configured to generate the tuning indication voltage Vind indicating the intensity of a frequency component other than 60 MHz.
equal to or lower than a particular value, the limiter circuit 31 outputs the analog signal from the BPF 28B to the BPF 32 without modification. On the other hand, in the case where the level of the analog signal that has passed through the BPF 28B is greater than the particular value, the limiter circuit 31 clips the analog signal from the BPF 28B so that the level of the analog signal becomes equal to or lower than the particular value, and then outputs the lowered analog signal to the BPF 32.
The BPF 32 attenuates, among the frequency components of the signal received from the limiter circuit 31, a component outside a particular pass band. For example, a center frequency Fc3 of the pass band of the BPF 32 is 60 MHz, and the pass band of the BPF 32 is the same as the pass band of the BPFs 28A and 28B. The bandwidth of BPF 32 and the bandwidths of the BPFs 28A, 28B may also be different from one another. The center frequency Fc3 is not limited to 60 MHz, but can be any frequency corresponding to the IF signal output by the mixer 26.
The wave detection circuit 33 performs envelope detection of the analog signal that has passed through the BPF 32, and outputs to the smoothing circuit 34 an envelope signal indicating the envelope of the analog signal from the BPF 32.
The smoothing circuit 34 generates the analog tuning indication voltage Vind by smoothing the envelope signal received from the wave detection circuit 33, and outputs the tuning indication voltage Vind to the automatic tuning unit 101.
Referring to
More specifically, the magnetron radar 301 exerts the best performance when the frequency of the IF signal output from the mixer 26 coincides with the center frequency Fc1 of the pass band of the BPF 28A, and can, for example, detect the target in the detection target area with high sensitivity.
In the tuning process, the automatic tuning unit 101 determines the level of the tuning control voltage Vcont at which the intensity of the component at the center frequency Fc1 in the IF signal output from the mixer 26 becomes maximum, based on the tuning indication voltage Vind received from the generation unit 30. For example, the level of the tuning control voltage Vcont is determined to be a value in a range from 1 volt to 9 volts. The level of the tuning control voltage Vcont is not limited to a value in the range from 1 volt to 9 volts, but determined to be a value in any arbitrary range.
As mentioned above, a magnetron is used for generating the transmission wave in the transmission unit 22. The transmission frequency ft of the transmission wave output by the transmission unit 22 has variations, for example, in a range of 9380 MHz to 9440 MHz, due to the influence of individual differences among magnetrons.
The automatic tuning unit 101 performs an initial tuning setting as a tuning process for compensating for the variations in the transmission frequency ft due to the individual differences among magnetrons during an initial setting period T1 including a timing when the magnetron radar 301 is mounted on a ship. Specifically, after mounting the magnetron radar 301 onto the ship, the seller of the magnetron radar 301 performs an operation for executing the initial tuning setting.
The automatic tuning unit 101 receives an operation from the seller of the magnetron radar 301 and performs the initial tuning setting during the initial setting period T1. The initial setting period T1 is an example of a first period. The automatic tuning unit 101 may also be configured to receive an operation from a person other than the seller of the magnetron radar 301 and perform the initial tuning setting.
Referring to
The automatic tuning unit 101 detects a tuning point Vt1, which is the level of the tuning control voltage Vcont at which the tuning indication voltage Vind becomes maximum, based on the scanning result of the level of the tuning control voltage Vcont in the scanning range Rs1 during the initial setting period T1. More specifically, the automatic tuning unit 101 detects the tuning point Vt1 based on the tuning property data D1 that are generated. The scanning range Rs1 is an example of a second range. The tuning point Vt1 is an example of a first level.
For example, the automatic tuning unit 101 detects the tuning point Vt1 for each pulse width PW of the transmission wave that can be output by the transmission unit 22. More specifically, the automatic tuning unit 101 outputs pulse information indicating the pulse width PW to the transmission control unit 21.
The transmission control unit 21 receives the pulse information from the automatic tuning unit 101 and changes the pulse width PW of the transmission trigger output to the transmission unit 22 to the pulse width PW indicated by the received pulse information.
The automatic tuning unit 101 detects the tuning point Vt1 when the transmission wave with the changed pulse width PW is output from the transmission unit 22. The automatic tuning unit 101 detects the tuning point Vt1 for each pulse width PW by switching the pulse width PW indicated by the pulse information addressed to the transmission control unit 21, and generates initial tuning information showing the correspondence relationship between the pulse width PW and the tuning point Vt1.
The automatic tuning unit 101 stores the generated initial tuning information in a non-volatile memory (not shown) and completes the initial tuning setting. The automatic tuning unit 101 determines the level of the tuning control voltage Vcont output to the local oscillator 27 based on the initial tuning information generated during the initial tuning setting, such as after the start of the detection process.
Here, the frequency of the transmission wave generated by using the magnetron has temperature dependence. Therefore, in the case where the temperature at the time of performing the detection process is different from the temperature during at the time of performing the initial tuning setting, the transmission frequency ft of the transmission wave output by the transmission unit 22 in the detection process may be different from the transmission frequency ft of the transmission wave output by the transmission unit 22 in the initial tuning setting.
Therefore, the automatic tuning unit 101 performs a transmission start search as a tuning process for compensating for the variation of the transmission frequency ft due to the temperature dependence of the magnetron during a detection setting period T2 that includes a timing of starting the detection process. Specifically, when the detection process is started by the magnetron radar 301, the user of the magnetron radar 301 performs an operation to execute the transmission start search.
The automatic tuning unit 101 receives the operation from the user and performs the transmission start search during the detection setting period T2. The detection setting period T2 is an example of a second period. The detection setting period T2 is a period different from the initial setting period T1, and is, for example, a period after the initial setting period T1. In the transmission start search, the automatic tuning unit 101 scans the level of the tuning control voltage Vcont output to the local oscillator 27 within a scanning range Rs2 of a particular size using the tuning point Vt1 as reference.
Referring to
After the start of the detection process, the automatic tuning unit 101 determines the level of the tuning control voltage Vcont output to the local oscillator 27 based on the tuning point Vt2 detected in the transmission start search.
For example, after the start of the detection process, the automatic tuning unit 101 executes tracking tuning periodically or irregularly as a tuning process. Specifically, in the tracking tuning, the automatic tuning unit 101 fine-tunes the level of the tuning control voltage Vcont output to the local oscillator 27 based on the tuning point Vt2 detected in the transmission start search by performing feedback control, so that the tuning indication voltage Vind received from the generation unit 30 has a larger value.
However, in the case where the temperature at the time of performing the transmission start search has significantly transitioned from the temperature at the time of performing the initial tuning setting, it may not be possible to correctly detect the tuning point Vt2 in the transmission start search.
Referring to
Furthermore, in the transmission start search, in the case where the value of the tuning control voltage Vcont corresponding to a peak P1 based on a harmonic component of the transmission wave falls within the scanning range Rs2, the tuning control voltage Vcont corresponding to the peak PI may be erroneously detected as the tuning point Vt2. In this case, in the detection process, the frequency of the IF signal output from the mixer 26 significantly deviates from the center frequency Fc1 of the pass band of the BPF 28A, so the detection sensitivity of the target in the detection target area decreases.
In addition, in the case where the temperature at the time when the setting of the detection range is changed according to an operation of the user after the detection process starts significantly deviates from the temperature at the time of performing the initial tuning setting, the tuning control voltage Vcont at which the tuning indication voltage Vind becomes maximum significantly differs from the tuning point Vt1 corresponding to the pulse width PW indicated by the initial tuning information. Therefore, with fine-tuning of the tuning control voltage Vcont in the tracking tuning, it is difficult to bring the frequency of the IF signal output from the mixer 26 close to the center frequency Fc1 of the pass band of the BPF 28A.
After the start of the detection process, instead of tracking tuning, it may be possible to bring the frequency of the IF signal output from the mixer 26 close to the center frequency Fc1 by performing FFT tuning for adjusting the level of the tuning control voltage Vcont output to the local oscillator 27 based on the frequency spectrum obtained by performing Fourier transform on the IF signal output from the mixer 26. However, in the case where the pulse width PW of the transmission wave is less than a particular value, it becomes difficult to perform FFT tuning because a sufficient number of samples of the IF signal cannot be obtained.
Therefore, the automatic tuning unit 101 according to the embodiment of the disclosure resolves the issue with the following configuration.
The communication unit 12 communicates with the transmission control unit 21 in the radar unit 201.
The acquisition unit 41 acquires the tuning indication voltage Vind indicating the intensity of the frequency component of 60 MHz in the output signal of the mixer 26. More specifically, the acquisition unit 41 generates a digital signal indicating the level of the tuning indication voltage Vind by performing digital conversion on the tuning indication voltage Vind received from the generation unit 30 in the radar unit 201, and outputs the digital signal to the computing unit 50.
The computing unit 50 determines the level of the tuning control voltage Vcont to be output to the local oscillator 27 based on the level indicated by the digital signal received from the acquisition unit 41. The computing unit 50 outputs a digital signal indicating the determined level to the output unit 42.
The output unit 42 outputs the tuning control voltage Vcont for adjusting the frequency of the LO signal applied to the mixer 26. More specifically, the output unit 42 generates the tuning control voltage Vcont by performing analog conversion on the digital signal received from the computing unit 50, and outputs the tuning control voltage Vcont to the local oscillator 27 in the radar unit 201.
The receiving unit 13, for example, receives an operation for executing the initial tuning setting from the seller of the magnetron radar 301, and outputs operation information C1 to the processing unit 11. The receiving unit 13 may also be configured to receive an operation from a person other than the seller of the magnetron radar 301 and output the operation information C1 to the processing unit 11.
The computing unit 50 in the processing unit 11 receives the operation information C1 from the receiving unit 13 and performs the initial tuning setting during the initial setting period T1. More specifically, the computing unit 50 generates pulse information indicating the pulse width PW and outputs an output instruction including the generated pulse information to the transmission control unit 21 in the radar unit 201 via the communication unit 12.
Referring to
The detection unit 51 detects the tuning point Vt1 for each pulse width PW by switching the pulse width PW indicated by the pulse information addressed to the transmission control unit 21, and generates the initial tuning information showing the correspondence relationship between the pulse width PW and the tuning point Vt1. The detection unit 51 stores the generated initial tuning information in the storage unit 14.
Furthermore, the setting unit 52 in the computing unit 50 sets a threshold Th1 based on a calculation range Rm1 that includes therein the tuning point Vt1 during the initial setting period T1. For example, the setting unit 52 sets the threshold Th1 based on the tuning indication voltage Vind during the initial setting period T1. More specifically, the setting unit 52 sets the threshold Th1 based on multiple tuning indication voltages Vind respectively corresponding to the levels of multiple tuning control voltage Vcont in the calculation range Rm1 that includes the tuning point Vt1 during the initial setting period T1. The calculation range Rm1 is an example of a first range. The threshold Th1 is an example of a reference value. The calculation range Rm1 is narrower than the scanning range Rs1.
For example, the setting unit 52 sets the threshold Th1 based on the accumulated value of the tuning control voltage Vcont in the calculation range Rm1. Specifically, the setting unit 52 sets the threshold Th1 based on an accumulated value SV1 of multiple tuning indication voltages Vind respectively corresponding to the levels of multiple tuning control voltages Vcont in the calculation range Rm1 during the initial setting period T1. For example, the setting unit 52 sets, as the threshold Th1, a value obtained by multiplying the accumulated value SV1 by a particular value equal to or more than zero and less than 1.
More specifically, the setting unit 52 calculates the accumulated value SV1 of multiple tuning indication voltages Vind respectively corresponding to multiple tuning control voltages Vcont at respective intervals N1 in the calculation range Rm1 from (Vt1-X1) volts to (Vt1+X1) volts. The setting unit 52 calculates as the threshold Th1 a value obtained by multiplying the calculated accumulated value SV1 by, for example, 0.6.
The setting unit 52 calculates the threshold Th1 for each pulse width PW and generates threshold information indicating the correspondence relationship between the pulse width PW and the threshold Th1. The setting unit 52 stores the generated threshold information in the storage unit 14.
(Accumulated Search when Transmission Starts)
The receiving unit 13, for example, receives an operation for executing the transmission start search from the user of the magnetron radar 301, and outputs received operation information C2 to the processing unit 11.
The computing unit 50 in the processing unit 11 receives the operation information C2 from the receiving unit 13, and performs an accumulated search instead of the transmission start search during the detection setting period T2.
More specifically, the computing unit 50 refers to the initial tuning information in the storage unit 14 and acquires the tuning point Vt1 corresponding to the pulse width PW of the transmission trigger currently output by the transmission control unit 21. Moreover, the computing unit 50 refers to the threshold information in the storage unit 14 and acquires the threshold Th1 corresponding to the pulse width PW of the transmission trigger currently output by the transmission control unit 21. The computing unit 50 performs the accumulated search by using the acquired tuning point Vt1 and threshold Th1.
Referring to
More specifically, the calculation unit 53 calculates the index value IV based on the accumulated value of the tuning indication voltage Vind. In other words, the calculation unit 53 calculates, as the index value IV, an accumulated value SV2 of multiple tuning indication voltages Vind respectively corresponding to multiple tuning control voltages Vcont at respective intervals N1 in the calculation range Rm1.
The determination unit 54 in the computing unit 50 determines the tuning control voltage Vcont output by the output unit 42 based on the comparison result between the index value IV and the threshold Th1. More specifically, the determination unit 54 determines an output level Vout, which is the level of the tuning control voltage Vcont to be output by the output unit 42, based on the comparison result between the index value IV and the threshold Th1, and the scanning result of the level of the tuning control voltage Vcont during the detection setting period T2.
For example, the determination unit 54 determines the output level Vout based on the scanning result of the level of the tuning control voltage Vcont in the scanning range Rs2, which is a range including the tuning point Vt1 and narrower than the scanning range Rs1, defined based on the tuning point Vt1.
For example, the calculation unit 53 calculates multiple index values IV by scanning with a width same as the calculation range Rm1. The determination unit 54 determines the tuning control voltage Vcont corresponding to the scanning position where the index value IV equal to or more than the threshold Th1 is calculated.
More specifically, in the example shown in
Referring to
For example, the determination unit 54 determines the output level Vout based on the scanning result of the level of the tuning control voltage Vcont in the scanning range Rs3, which is a range including the tuning point Vt1 and narrower than the scanning range Rs1, defined based on the tuning point Vt1.
More specifically, in the example shown in
In other words, in the case where the index value IV is less than the threshold Th1, the determination unit 54 performs an extended transmission start search instead of the transmission start search. In the extended transmission start search, the determination unit 54 generates the tuning property data D3 showing the correspondence relationship between the tuning control voltage Vcont and the tuning indication voltage Vind in the scanning range Rs3 by scanning the level of the tuning control voltage Vcont output to the local oscillator 27 at intervals N2 from (Vt1−X2) volts to (Vt1+X2) volts in the scanning range Rs3. The interval N2 may be the same as or different from the interval N1.
Based on the generated tuning property data D3, the determination unit 54 detects a tuning point Vt3, which is the tuning control voltage Vcont when the tuning indication voltage Vind is at maximum. The determination unit 54 determines the detected tuning point Vt3 as the output level Vout.
In the case where an operation for changing change the setting of the detection range is received from the user of the magnetron radar 301 after the start of the detection process, the receiving unit 13 in the automatic tuning unit 101 outputs the received operation information C3 to the processing unit 11.
The computing unit 50 in the processing unit 11 receives the operation information C3 from the receiving unit 13 and outputs the pulse information indicating the pulse width PW corresponding to the detection range after the setting change to the transmission control unit 21. Additionally, the computing unit 50 receives the operation information C3 from the receiving unit 13 and, during the detection period T3 after the start of the detection process, performs an accumulated search. The detection period T3 is, for example, a period after the initial setting period T1 and the detection setting period T2.
More specifically, the computing unit 50 refers to the initial tuning information in the storage unit 14 and acquires the tuning point Vt1 corresponding to the pulse width PW after change. Additionally, the computing unit 50 refers to the threshold information in the storage unit 14 and acquires the threshold Th1 corresponding to the pulse width PW after change. The computing unit 50 performs the accumulated search by using the acquired tuning point Vt1 and threshold Th1.
Referring again to
As shown in
On the other hand, as shown in
The magnetron radar according to the embodiment of the disclosure includes a computer having a memory, and the processor such as a CPU in the computer reads and executes, from the memory, a program that includes some or all of the respective steps in the following flowchart and sequence. The program of the device can be disposed externally. The program of the device can be distributed in a state stored on a recording medium or via a communication line.
Referring to
Next, the automatic tuning unit 101 detects the tuning point Vt1 based on the generated tuning property data D1 (Step S13).
Next, the automatic tuning unit 101 calculates the accumulated value SV1 of multiple tuning indication voltages Vind respectively corresponding to multiple tuning control voltages Vcont in the calculation range Rm1 (Step S14).
Next, the automatic tuning unit 101 calculates, as the threshold Th1, a value obtained by multiplying the calculated accumulated value SV1 by, for example, 0.6, and stores the calculated threshold Th1 in the storage unit 14 (Step S15).
Referring to
Next, the automatic tuning unit 101 compares the calculated index value IV with the threshold Th1 (Step S23).
Next, in the case where the index value IV is equal to or more than the threshold Th1 (YES in Step S24), the automatic tuning unit 101 generates the tuning property data D2 by performing the transmission start search (Step S25).
Next, the automatic tuning unit 101 detects the tuning point Vt2 based on the generated tuning property data D2 (Step S26).
Next, the automatic tuning unit 101 determines the detected tuning point Vt2 as the output level Vout, which is the level of the tuning control voltage Vcont to be output to the local oscillator 27 (Step S27).
On the other hand, in the case where the index value IV is less than the threshold Th1 (NO in Step S24), the automatic tuning unit 101 performs the extended transmission start search. More specifically, the automatic tuning unit 101 generates the tuning property data D3 showing the correspondence relationship between the tuning control voltage Vcont and the tuning indication voltage Vind in the scanning range Rs3 by scanning the level of the tuning control voltage Vcont output to the local oscillator 27 in the scanning range Rs3 (Step S28).
Next, the automatic tuning unit 101 detects the tuning point Vt3 based on the generated tuning property data D3 (Step S29).
Next, the automatic tuning unit 101 determines the detected tuning point Vt3 as the output level Vout, which is the level of the tuning control voltage Vcont to be output to the local oscillator 27 (Step S27).
Referring to
Next, the automatic tuning unit 101 in the magnetron radar 301 calculates, as the index value IV, the accumulated value SV2 of multiple tuning indication voltages Vind respectively corresponding to multiple tuning control voltages Vcont in the calculation range Rm1 (Step S32).
Next, the automatic tuning unit 101 compares the calculated index value IV with the threshold Th1 (Step S33).
Next, in the case where the index value IV is equal to or more than the threshold Th1 (YES in Step S34), the automatic tuning unit 101 determines the tuning point Vt1 as the output level Vout and starts tracking tuning or FFT tuning (Step S35).
On the other hand, in the case where the index value IV is less than the threshold Th1 (NO in Step S34), the automatic tuning unit 101 performs the extended transmission start search. More specifically, the automatic tuning unit 101 generates the tuning property data D3 showing the correspondence relationship between the tuning control voltage Vcont and the tuning indication voltage Vind in the scanning range Rs3 by scanning the level of the tuning control voltage Vcont output to the local oscillator 27 in the scanning range Rs3 (Step S36).
Next, the automatic tuning unit 101 detects the tuning point Vt3 based on the generated tuning property data D3 (Step S37).
Next, the automatic tuning unit 101 determines the detected tuning point Vt3 as the output level Vout (Step S35).
In the magnetron radar 301 according to the embodiment of the disclosure, it is configured that the radar unit 201 includes the generation unit 30. However, the disclosure is not limited to this configuration. Instead of the radar unit 201, the automatic tuning unit 101 may also include the generation unit 30.
Furthermore, in the magnetron radar 301 according to the embodiment of the disclosure, it is configured that the computing unit 50 in the automatic tuning unit 101 sets the threshold Th1 based on the tuning indication voltage Vind in the calculation range Rm1 and calculates the index value IV based on the tuning indication voltage Vind in the calculation range Rm1. However, the disclosure is not limited to this configuration. The setting unit 52 may also be configured to set the threshold Th1 based on the tuning indication voltage Vind in the calculation range Rm1, while the calculation unit 53 may also be configured to calculate the index value IV based on the tuning indication voltage Vind in the calculation range Rm2 different from the calculation range Rm1.
Moreover, in the magnetron radar 301 according to the embodiment of the disclosure, it is configured that the setting unit 52 in the automatic tuning unit 101 calculates the accumulated value SV1 of multiple tuning indication voltages Vind respectively corresponding to multiple tuning control voltages Vcont in the calculation range Rm1, and calculates, as the threshold Th1, a value obtained by multiplying the calculated accumulated value SV1 by, for example, 0.6. However, the disclosure is not limited to this configuration. The setting unit 52 may be configured to calculate, as the threshold Th1, a value obtained by multiplying the accumulated value SV1 by a value other than 0.6.
Additionally, the setting unit 52 may also be configured to calculate other statistical values, etc., instead of the accumulated value SV1.
Furthermore, in the magnetron radar 301 according to the embodiment of the disclosure, it is configured that the determination unit 54 in the automatic tuning unit 101 compares the threshold Th1 calculated in the initial tuning setting with the index value IV in the accumulated search. However, the disclosure is not limited to this configuration. For example, the determination unit 54 may be configured to calculate a new threshold Th1 by multiplying the index value IV calculated in the accumulated search by a particular coefficient, and update the threshold Th1 in the storage unit 14 to the calculated threshold Th1. In this case, the determination unit 54 compares the updated threshold Th1 with the index value IV in the next accumulated search.
Referring to
Referring to
In the case where the index value IV is equal to or more than the threshold Th1, the determination unit 54 generates the tuning property data D2 by performing the transmission start search, and detects the tuning point Vt2 based on the generated tuning property data D2. The determination unit 54 determines the detected tuning point Vt2 as the output level Vout. In the example shown in
Referring to
In the case where the index value IV is less than the threshold Th1, the determination unit 54 generates the tuning property data D3 by performing the extended transmission start search, and detects the tuning point Vt3 based on the generated tuning property data D3. The determination unit 54 determines the detected tuning point Vt3 as the output level Vout.
In the tuning process, a technique that enables more suitable control on the frequency of the carrier signal provided to the mixer is desired.
In response to this, in the automatic tuning unit 101 according to the embodiment of the disclosure, the output unit 42 outputs the tuning control voltage Vcont for adjusting the frequency of the LO signal provided to the mixer 26. The acquisition unit 41 acquires the tuning indication voltage Vind indicating the intensity of the frequency component of 60 MHz in the output signal of the mixer 26. The setting unit 52 sets the threshold Th1 based on multiple tuning indication voltages Vind respectively corresponding to the levels of multiple tuning control voltages Vcont in the calculation range Rm1 including the tuning point Vt1 during the initial setting period T1. The calculation unit 53 calculates the index value IV based on multiple tuning indication voltages Vind respectively corresponding to the levels of multiple tuning control voltage Vcont in the calculation range Rm1 including the tuning point Vt1 during the detection setting period T2. The determination unit 54 determines the output level Vout, which is the level of the tuning control voltage Vcont to be output in the output unit 42, based on the comparison result between the index value IV and the threshold Th1 and the scanning result of the level of the tuning control voltage Vcont during the detection setting period T2.
In this way, with the configuration of determining the output level Vout of the tuning control voltage Vcont based on the comparison result between the index value IV and the threshold Th1, and the scanning result of the level of the tuning control voltage Vcont during the detection setting period T2, it is possible to determine the output level Vout by considering the comparison result between the index value IV based on the tuning indication voltage Vind during the detection setting period T2 and the threshold Th1 based on the tuning indication voltage Vind during the initial setting period T1. Therefore, in the case where the tuning point during the detection setting period T2 transitions from the tuning point during the initial setting period T1 due to the temperature dependence of the magnetron, it is possible to recognize the transition of the tuning point based on the comparison result between the index value IV and the threshold Th1 and determine a more suitable output level Vout for tuning by taking into consideration the transition of the tuning point. Consequently, in the tuning process, it is possible to more suitably control the frequency of the LO signal provided to the mixer 26.
Furthermore, by using the comparison result between the index value IV and the threshold Th1, it is possible to recognize the transition of the tuning point according to the degree of similarity between the peak shape of the tuning indication voltage Vind during the initial setting period T1 and the peak shape of the tuning indication voltage Vind during the detection setting period T2. Additionally, since the width of the peak shape of the tuning indication voltage Vind based on harmonic components is smaller than the width of the peak shape of the tuning indication voltage Vind based on the tuning point, by determining the output level Vout by considering the comparison result between the index value IV and the threshold Th1, it is possible to prevent erroneously detecting, as the tuning point, the tuning control voltage Vcont corresponding to the peak of the tuning indication voltage Vind based on harmonic components.
The embodiments should be considered as exemplary in all aspects and not restrictive. The scope of the disclosure is indicated by the claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the claims.
It is to be understood that not necessarily all objects or advantages may be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that certain embodiments may be configured to operate in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
All of the processes described herein may be embodied in, and fully automated via, software code modules executed by a computing system that includes one or more computers or processors. The code modules may be stored in any type of non-transitory computer-readable medium or other computer storage device. Some or all the methods may be embodied in specialized computer hardware.
Many other variations than those described herein will be apparent from this disclosure. For example, depending on the embodiment, certain acts, events, or functions of any of the algorithms described herein can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, acts or events can be performed concurrently, e.g., through multi-threaded processing, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially. In addition, different tasks or processes can be performed by different machines and/or computing systems that can function together.
The various illustrative logical blocks and modules described in connection with the embodiments disclosed herein can be implemented or performed by a machine, such as a processor. A processor can be a microprocessor, but in the alternative, the processor can be a controller, microcontroller, or state machine, combinations of the same, or the like. A processor can include electrical circuitry configured to process computer-executable instructions. In another embodiment, a processor includes an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable device that performs logic operations without processing computer-executable instructions. A processor can also be implemented as a combination of computing devices, e.g., a combination of a digital signal processor (DSP) and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Although described herein primarily with respect to digital technology, a processor may also include primarily analog components. For example, some or all of the signal processing algorithms described herein may be implemented in analog circuitry or mixed analog and digital circuitry. A computing environment can include any type of computer system, including, but not limited to, a computer system based on a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computational engine within an appliance, to name a few.
Conditional language such as, among others, “can,” “could,” “might” or “may,” unless specifically stated otherwise, are otherwise understood within the context as used in general to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment.
Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain embodiments require at least one of X, at least one of Y, or at least one of Z to each be present.
Any process descriptions, elements or blocks in the flow diagrams described herein and/or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or elements in the process. Alternate implementations are included within the scope of the embodiments described herein in which elements or functions may be deleted, executed out of order from that shown, or discussed, including substantially concurrently or in reverse order, depending on the functionality involved as would be understood by those skilled in the art.
Unless otherwise explicitly stated, articles such as “a” or “an” should generally be interpreted to include one or more described items. Accordingly, phrases such as “a device configured to” are intended to include one or more recited devices. Such one or more recited devices can also be collectively configured to carry out the stated recitations. For example, “a processor configured to carry out recitations A, B and C” can include a first processor configured to carry out recitation A working in conjunction with a second processor configured to carry out recitations B and C. The same holds true for the use of definite articles used to introduce embodiment recitations. In addition, even if a specific number of an introduced embodiment recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations).
It will be understood by those within the art that, in general, terms used herein, are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.).
For expository purposes, the term “horizontal” as used herein is defined as a plane parallel to the plane or surface of the floor of the area in which the system being described is used or the method being described is performed, regardless of its orientation. The term “floor” can be interchanged with the term “ground” or “water surface”. The term “vertical” refers to a direction perpendicular to the horizontal as just defined. Terms such as “above,” “below,” “bottom,” “top,” “side,” “higher,” “lower,” “upper,” “over,” and “under,” are defined with respect to the horizontal plane.
As used herein, the terms “attached,” “connected,” “mated,” and other such relational terms should be construed, unless otherwise noted, to include removable, moveable, fixed, adjustable, and/or releasable connections or attachments. The connections/attachments can include direct connections and/or connections having intermediate structure between the two components discussed.
Numbers preceded by a term such as “approximately”, “about”, and “substantially” as used herein include the recited numbers, and also represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, and “substantially” may refer to an amount that is within less than 10% of the stated amount. Features of embodiments disclosed herein preceded by a term such as “approximately”, “about”, and “substantially” as used herein represent the feature with some variability that still performs a desired function or achieves a desired result for that feature.
It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-115390 | Jul 2022 | JP | national |
The present application is a continuation of PCT/JP2023/022829, filed on Jun. 20, 2023, and is related to and claims priority from Japanese patent application no. 2022-115390, filed on Jul. 20, 2022. The entire contents of the aforementioned application are hereby incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2023/022829 | Jun 2023 | WO |
| Child | 18915328 | US |
