Microwave frequency measuring device and method

Abstract

The invention provides a microwave frequency measuring device and method. The microwave frequency measuring device comprises a light source, a microwave receiving module, an electro-optical modulation module, an optical signal processing module, a photoelectric detection module and a photon integration platform, the light source is used for generating a laser signal, the microwave receiving module is used for receiving an external microwave signal, and the electro-optical modulation module modulates the external microwave signal onto the laser signal and generates a modulated light signal; the modulated optical signal generates 2n output optical signals through n optical signal processing units of an optical signal processing module on the photon integration platform, and the 2n output optical signals are converted into corresponding electric signals through a photoelectric detection module; an amplitude ratio function is established based on two output optical signals of an optical signal processing unit, so that n amplitude ratio functions can be obtained; and through simultaneous establishment of n amplitude ratio functions, the frequency of the modulated optical signal is obtained in any interval with a unique frequency solution, and the frequency of the external microwave signal is obtained. The method has the advantages of being large in bandwidth, high in precision and capable of achieving rapid and real-time measurement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of microwave measurement, in particular to a microwave frequency measurement device and method. BACKGROUND

[0002] Microwave real-time frequency measurement has extremely important significance in many fields such as modern communication, radar, electronic countermeasures, aerospace, etc., among which the precision of microwave frequency measurement is particularly important. For example, in the 6G communication system, it is required to support microwave measurement in the terahertz frequency band (100 GHz), and under the support of ultra-high precision, the communication system can perform ultra-high precision environmental perception and real-time dynamic spectrum management.

[0003] The existing frequency measurement methods include measurement methods based on microwave photonics technology, measurement methods based on traditional electronic technology, measurement methods based on frequency-modulated continuous wave radar, and measurements based on double optical frequency comb and stimulated Brillouin scattering. Among them, the microwave frequency measurement method based on traditional electronic technology mainly relies on electronic components and circuits to directly process microwave signals. With the rapid development of electronic information technology, the advantages are particularly obvious, and it has the advantages of simple implementation, low cost and high precision. However, the microwave frequency measurement method based on traditional electronic technology has limited measurement range, poor anti-interference ability and insufficient real-time performance, which cannot meet the requirements of ultra-high precision microwave frequency measurement.

[0004] Therefore, how to design a microwave frequency measurement device and method with high precision, ultra-wide bandwidth, good real-time performance and strong anti-interference ability has become one of the problems to be solved by the person skilled in the art.

[0005] It should be noted that the above introduction to the technical background is only to facilitate the clear and complete description of the technical scheme of the present application, and to facilitate the understanding of the person skilled in the art. The above technical scheme cannot be considered as known to the person skilled in the art merely because it is described in the background section of the present application. SUMMARY

[0006] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a microwave frequency measurement device and method to solve the problem of limited measurement range, poor anti-interference ability and insufficient real-time performance of the microwave frequency measurement method in the prior art.

[0007] To achieve the above object and other related objects, the present application provides a microwave frequency measurement device, which comprises at least a light source, a microwave receiving module, an electro-optical modulation module, an optical signal processing module, an optoelectronic detection module and a photonic integrated platform; the light source is used to generate a laser signal; the microwave receiving module is used to receive an external microwave signal; the electro-optical modulation module receives the laser signal based on an optical input port, receives the external microwave signal based on an electrical input port, and modulates the external microwave signal onto the laser signal to generate a modulated optical signal; the optical signal processing module is formed on the photonic integrated platform; the optical signal processing module receives the modulated optical signal and divides the modulated optical signal into n parts; the optical signal processing module comprises n optical signal processing units, each of which receives one of the n parts of the modulated optical signal, and each optical signal processing unit generates two output optical signals; n is a natural number greater than or equal to 2; the optoelectronic detection module is used to convert optical signals into electrical signals; the optoelectronic detection module comprises n optoelectronic detection units, which correspond to the optical signal processing units one by one and receive the two output optical signals of the optical signal processing units; wherein, n amplitude ratio functions are established based on the output optical signals of the n optical signal processing units, the slopes of the n amplitude ratio functions decrease and the frequency periods of the n amplitude ratio functions increase, the amplitude ratio function is a periodic function of optical amplitude ratio and optical signal frequency; the frequencies of the modulated optical signal are obtained in any interval where there is a unique frequency solution by simultaneously solving the n amplitude ratio functions, and then the frequency of the external microwave signal is obtained.

[0008] Optionally, the value of n is 2; the optical signal processing module comprises first and second optical signal processing units; the optoelectronic detection module comprises first and second optoelectronic detection units; the first optical signal processing unit outputs first and second output optical signals, and the second optical signal processing unit outputs third and fourth output optical signals; the first optoelectronic detection unit receives the first and second output optical signals, and the second optoelectronic detection unit receives the third and fourth output optical signals.

[0009] More optionally, the first optical signal processing unit comprises a first bus waveguide, a first micro-ring waveguide and a second bus waveguide; the first bus waveguide receives a corresponding modulated optical signal, is used to couple part of the modulated optical signal to the first micro-ring waveguide, and couple another part of the modulated optical signal as the first output optical signal; the first micro-ring waveguide receives part of the modulated optical signal and is coupled to the second bus waveguide; the second bus waveguide receives the optical signal transmitted by the first micro-ring waveguide and outputs the second output optical signal.

[0010] More optionally, the second optical signal processing unit is a Mach-Zehnder interferometer.

[0011] More optionally, the second optical signal processing unit comprises a third bus waveguide, a second micro-ring waveguide and a fourth bus waveguide; the third bus waveguide receives the corresponding modulated optical signal, for coupling part of the modulated optical signal to the second micro-ring waveguide, and coupling another part of the modulated optical signal as the third output optical signal; the second micro-ring waveguide receives part of the modulated optical signal, and is coupled to the fourth bus waveguide; the fourth bus waveguide receives the optical signal transmitted by the second micro-ring waveguide, and outputs the fourth output optical signal.

[0012] Optionally, the electro-optical modulation module is formed on the photonic integrated platform.

[0013] More optionally, the light source is formed on the photonic integrated platform.

[0014] Optionally, the first and second photodetector modules are formed on the photonic integrated platform.

[0015] To achieve the above object and other related objects, the present application also provides a microwave frequency measurement method, steps of the microwave frequency measurement method at least include: S1: providing a laser signal and an external microwave signal; modulating the external microwave signal on the laser signal to generate a modulated optical signal; the modulated optical signal is divided into n optical signals, each optical signal generates 2 output optical signals, 1 amplitude ratio function is established based on 2 output optical signals of 1 optical signal and n amplitude ratio functions are obtained, slopes of the n amplitude ratio functions decrease and frequency periods increase; wherein, n is a natural number greater than or equal to 2, the amplitude ratio function is a periodic function about optical amplitude ratio and optical signal frequency; S2: simultaneously solving n amplitude ratio functions, obtaining the frequency of the modulated optical signal in an interval where there is a unique frequency solution, and obtaining the frequency of the external microwave signal based on the frequency of the modulated optical signal; wherein, frequency characteristics of 2n output optical signals are the same and consistent with the frequency characteristics of the modulated optical signal.

[0016] Optionally, in step S1, in 2 output optical signals of 1 optical signal, one optical amplitude function is established based on optical amplitude and frequency of one output optical signal, and another optical amplitude function is established based on optical amplitude and frequency of another output optical signal; a corresponding amplitude ratio function is established based on a ratio of a pair of optical amplitude functions.

[0017] Optionally, in step S2, a least common multiple frequency period about n amplitude ratio functions is obtained, and a length of the interval where there is a unique frequency solution is less than or equal to one half of the least common multiple frequency period.

[0018] As described above, the microwave frequency measurement device and method of the present application have the following beneficial effects:

[0019] 1. The present invention obtains a corresponding amplitude ratio function through an optical signal processing unit, obtaining a total of n amplitude ratio functions. By combining the n amplitude ratio functions, the accuracy of the modulated optical signal can reach the highest accuracy among the n amplitude ratio functions, and the solution bandwidth of the modulated optical signal can reach half of the least common multiple period of the n amplitude ratio functions. This breaks the mutual constraint between accuracy and bandwidth, and the present invention can achieve high-precision and large-bandwidth microwave frequency measurement.

[0020] 2. The present invention can freely set the starting point of the interval within one-half of the least common multiple period, so that technicians can select low, medium and high frequency bands in the full frequency band according to their own needs, meet different industrial needs, and have a wide range of application scenarios.

[0021] 3. The present invention integrates the light source, electro-optical modulation module, optical signal processing module and photoelectric detection module on a photonic integration platform, and then connects the microwave receiving module with the electro-optical modulation module on the photonic integration platform, so that the microwave frequency measurement device can be used as a whole to meet the needs of large-scale optoelectronic integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Shown is a schematic structural diagram of a device for measuring microwave frequency.

[0023] Figure 2 Schematic diagram showing a single cycle of the amplitude comparison function of a device for measuring microwave frequencies.

[0024] Figure 3 It shows a first structural schematic diagram of the microwave frequency measuring device of the present invention.

[0025] Figure 4 Shown is a schematic diagram of the slope of the amplitude ratio function of the present invention.

[0026] Figure 5 Shown is a schematic diagram of the first amplitude ratio function of the present invention.

[0027] Figure 6 Shown is a schematic diagram of the second amplitude ratio function of the present invention.

[0028] Figure 7 It shows a schematic diagram of the simultaneous mapping of the first amplitude ratio function and the second amplitude ratio function of the present invention.

[0029] Figure 8 It shows a second structural schematic diagram of the microwave frequency measuring device of the present invention.

[0030] Figure 9 It shows a third structural schematic diagram of the microwave frequency measuring device of the present invention.

[0031] Figure 10 Fig. 4 shows a fourth structural schematic diagram of the microwave frequency measurement device of the present application.

[0032] Figure 11 Fig. 5 shows a flow schematic diagram of the microwave frequency measurement method of the present application.

[0033] Figure 12 Fig. 6 shows a formula combined schematic diagram of the first amplitude ratio function and the second amplitude ratio function of the present application.

[0034] Element number explanation

[0035] 1 light source

[0036] 2 microwave signal receiving module

[0037] 3 electro-optical modulation module

[0038] 4 optical signal processing module

[0039] 41 first optical signal processing unit

[0040] 42 second optical signal processing unit

[0041] 43 third optical signal processing unit

[0042] 5 photoelectric detection module

[0043] 51 first photoelectric detection unit

[0044] 52 second photoelectric detection unit

[0045] 53 third photoelectric detection unit

[0046] 5a first photoelectric detector

[0047] 5b second photoelectric detector

[0048] 5c third photoelectric detector

[0049] 5d fourth photoelectric detector

[0050] 5e fifth photoelectric detector

[0051] 5f sixth photoelectric detector

[0052] 6 photonic integrated module DETAILED DESCRIPTION

[0053] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0054] See also Figures 1-12 It should be noted that the diagrams provided in this embodiment are merely schematic illustrations of the basic concept of the present invention. Therefore, the diagrams only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0055] like Figure 1 As shown, a device can be used to measure microwave frequency. An electro-optical modulator modulates an external microwave signal onto a laser signal. The modulated optical signal is then input into a waveguide structure composed of a straight waveguide, a microring waveguide, and a U-shaped waveguide to generate two output optical signals. Two photodetectors receive the two output optical signals, respectively. Next, an optical amplitude function is derived based on the frequency and amplitude of one output optical signal, and another optical amplitude function is derived based on the frequency and amplitude of the other output optical signal. An amplitude comparison function can be derived based on the ratio of the two optical amplitude functions. Therefore, the measured amplitude ratio of the two output optical signals (the value of the dependent variable) can be used to determine the frequency of the optical signal modulated by the electro-optical modulator (the value of the independent variable). Based on the frequency of the modulated optical signal, the frequency of the external microwave signal can be determined.

[0056] but Figure 1 The optical chip shown has the following problems: Figure 2 As shown in the figure, the higher the slope of the amplitude comparison function, the higher the frequency accuracy of the modulated optical signal, that is, the higher the frequency accuracy of the external microwave signal; however, under the same extinction ratio, the higher the slope, the narrower the frequency range corresponding to the modulated optical signal, that is, the narrower the frequency range of the external microwave signal. Therefore, Figure 1 The optical chip shown has a mutual constraint relationship between accuracy and bandwidth. In summary, in order to achieve a large bandwidth and high-precision measurement effect, the present invention provides a microwave frequency measurement device and method. The specific technical solutions are as follows:

[0057] Example 1

[0058] like Figure 3 As shown, this embodiment provides a microwave frequency measurement device, including: a light source 1, a microwave signal receiving module 2, an electro-optical modulation module 3, an optical signal processing module 4, a photoelectric detection module 5 and a photonic integration platform 6.

[0059] As shown in Figure 3 , the light source 1 is used to generate a laser signal; the microwave receiving module 2 is used to receive an external microwave signal; the electro-optical modulation module 3 receives the laser signal based on the optical input port, receives the external microwave signal based on the electrical input port, and modulates the external microwave signal onto the laser signal to generate a modulated light signal.

[0060] Specifically, in this embodiment, the frequency of the modulated light signal generated by the electro-optical modulation module 3 is jointly determined by the frequency of the laser signal and the frequency of the external microwave signal. Since the frequency of the provided laser signal is known, if the frequency of the modulated light signal can be obtained, the frequency of the external microwave signal can be obtained. As an example, as shown in Figure 3 , the light source 1 device generating the laser signal uses a laser, the microwave receiving module 2 uses a microwave antenna, and the electro-optical modulation module 3 uses an electro-optical modulator. In actual applications, the specific types of the light source 1, the microwave receiving module 2, and the electro-optical modulation module 3 are selected as needed, and are not limited to this embodiment.

[0061] As shown in Figure 3 , the optical signal processing module 4 is formed on the photonic integrated platform 6; the optical signal processing module 4 receives the modulated light signal and divides the modulated light signal into n parts; the optical signal processing module 4 includes n optical signal processing units, and the n optical signal processing units one-to-one correspond to receive the n parts of the modulated light signal, and each optical signal processing unit generates two output light signals; n is a natural number greater than or equal to 2.

[0062] Specifically, in this embodiment, as shown in Figure 3As shown, n optical signal processing units are formed on the photonic integrated platform 6, and the integration of the device can be improved by using the photonic integrated platform 6. As an example, the photonic integrated platform 6 can be formed by sequentially stacking a substrate layer and a lower cladding layer (the lower cladding layer prevents the optical signal from entering the substrate layer). In actual applications, the specific composition of the photonic integrated platform 6 is selected as needed, and is not limited to this embodiment. Further, the n optical signal processing units collectively receive the modulated optical signal, which is equivalent to dividing the modulated optical signal into n parts, and the n parts of the modulated optical signal are transmitted one by one to the n optical signal processing units. One optical signal processing unit generates two output optical signals, and the optical signal processing module 4 generates a total of 2n output optical signals. Further, in the two output optical signals of one optical signal processing unit, an optical amplitude function is established based on the frequency (independent variable) and optical amplitude (dependent variable) of one output optical signal, and another optical amplitude function is established based on the frequency and optical amplitude of the other output optical signal. By comparing the two optical amplitude functions, the amplitude ratio function of the optical signal processing unit is obtained, and n amplitude ratio functions are obtained in this way. Wherein, since the optical signal processing module 4 does not change the frequency characteristics of the optical signal, the frequency characteristics of the n amplitude ratio functions are consistent, and are consistent with the frequency characteristics of the modulated optical signal.

[0063] Specifically, in this embodiment, when n is 2, the microwave frequency measurement device can achieve large bandwidth and high precision measurement effect with the least optical signal processing unit. The optical signal processing module 4 includes a first optical signal processing unit and a second optical signal processing unit. The photoelectric detection module 5 includes a first photoelectric detection unit and a second photoelectric detection unit. Further, the first optical signal processing unit 41 outputs a first output optical signal and a second output optical signal, and the second optical signal processing unit 42 outputs a third output optical signal and a fourth output optical signal. Further, the first photoelectric detection unit 51 corresponds to the first optical signal processing unit 41 and receives the first output optical signal and the second output optical signal. The second photoelectric detection unit 52 corresponds to the second optical signal processing unit 42 and receives the third output optical signal and the fourth output optical signal. In actual applications, n is selected as needed, and is not limited to this embodiment.

[0064] Specifically, in this embodiment, the first optical signal processing unit 41 includes a first bus waveguide, a first micro-ring waveguide, and a second bus waveguide. First, the first bus waveguide is used to receive the corresponding part of the modulated optical signal and output part of the modulated optical signal as the first output optical signal. Second, the first micro-ring waveguide is optically coupled with the first bus waveguide and obtains another part of the modulated optical signal from the first bus waveguide, wherein the first micro-ring waveguide is located between the first bus waveguide and the second bus waveguide. Finally, the second bus waveguide is optically coupled with the first micro-ring waveguide and obtains the optical signal in the first micro-ring waveguide, and the second bus waveguide outputs the second output optical signal. As an example, as shown in FIG. 4, the first bus waveguide 411 is used to receive the corresponding part of the modulated optical signal and output part of the modulated optical signal as the first output optical signal. The first micro-ring waveguide 412 is optically coupled with the first bus waveguide 411 and obtains another part of the modulated optical signal from the first bus waveguide 411. The second bus waveguide 413 is optically coupled with the first micro-ring waveguide 412 and obtains the optical signal in the first micro-ring waveguide 412, and the second bus waveguide 413 outputs the second output optical signal. Figure 3As shown, the first bus waveguide is a first straight waveguide, and the second bus waveguide is a U-shaped waveguide composed of a second straight waveguide, a first curved waveguide and a third straight waveguide connected in sequence: the first bus waveguide is adjacent to the curved waveguide on the first side of the first micro-ring waveguide, and the curved waveguide on the opposite side of the first micro-ring waveguide is adjacent to the second straight waveguide of the second bus waveguide; therefore, after the first bus waveguide receives the modulated optical signal, part of the modulated optical signal in the first bus waveguide is output as the first output optical signal in the first bus waveguide, and another part of the modulated optical signal in the first bus waveguide is coupled and transmitted into the first micro-ring waveguide, and then coupled from the first micro-ring waveguide to the second bus waveguide, and the second bus waveguide outputs the second output optical signal; wherein the optical signal transmission directions in the first straight waveguide and the third straight waveguide are the same. In actual application, the specific structure of the first optical signal processing unit 41 can be set according to needs, which is not limited by the present embodiment.

[0065] Specifically, in the present embodiment, as shown in Figure 3 The second optical signal processing unit 42 can be a Mach-Zehnder interferometer, which generates and outputs the third output optical signal in one interference arm and generates and outputs the fourth output optical signal in the other interference arm after receiving the corresponding portion of the modulated optical signal. Further, the second optical signal processing unit 42 can also be a waveguide combination structure including a third bus waveguide, a second micro-ring waveguide and a fourth bus waveguide: the third bus waveguide receives the corresponding portion of the modulated optical signal, part of the modulated optical signal in the third bus waveguide is output as the third output optical signal, and another part of the modulated optical signal in the third bus waveguide is coupled to the second micro-ring waveguide, and then coupled from the second micro-ring waveguide to the fourth bus waveguide, and the fourth bus waveguide outputs the fourth output optical signal; that is, the second optical signal processing unit 42 also adopts the combination of straight waveguides, micro-ring waveguides and U-shaped waveguides as the first optical signal processing unit 41. Further, the first amplitude ratio function and the second amplitude ratio function obtained by the first optical signal processing unit and the second optical signal processing unit respectively need to satisfy the conditions of decreasing slope and increasing frequency period.

[0066] As shown in Figure 3 The photoelectric detection module 5 is used for converting optical signals into electrical signals, and includes n photoelectric detection units, each of which corresponds to an optical signal processing unit and receives two output optical signals of the optical signal processing unit.

[0067] Specifically, in the present embodiment, one photoelectric detection unit corresponds to and receives two output optical signals of one optical signal processing unit, and converts the two output optical signals into corresponding electrical signals. Further, by analyzing the frequencies and optical amplitudes of the 2n output optical signals represented by the 2n electrical signals, the relationship between the frequencies and optical amplitudes of the 2n output optical signals can be obtained, and then n amplitude ratio functions can be established. As an example, n is 2, as shown in Figure 4As shown, the first photoelectric detection unit 51 includes a first photoelectric detector 5a and a second photoelectric detector 5b: the first photoelectric detector 5a is used to receive one output light signal output by the first light signal processing unit, and the second photoelectric detector 5b is used to receive another output light signal output by the first light signal processing unit; the second photoelectric detection unit 52 includes a third photoelectric detector 5c and a fourth photoelectric detector 5d, the third photoelectric detector 5c is used to receive one output light signal output by the second light signal processing unit, and the fourth photoelectric detector 5d is used to receive another output light signal output by the second light signal processing unit. In actual application, the specific structure of each photoelectric detection unit is set according to the needs, which is not limited to the embodiment.

[0068] It should be noted that by measuring the light amplitude ratio generated by the n amplitude ratio functions at the same modulation light frequency, the modulation light frequency can be obtained in any interval where the frequency has a unique solution, and based on the modulation light frequency, the frequency of the corresponding external microwave signal can be obtained; wherein the amplitude ratio function is a periodic function of the light amplitude ratio and the light signal frequency, and as Figure 5 shown, the slope of the amplitude ratio function refers to the slope between the maximum value and the minimum value of the amplitude ratio function in the same period. As an example, n is 2, the first light signal processing module 41 can obtain the light amplitude functions of the first output light signal and the second output light signal, and based on the ratio of the first light amplitude function to the second light amplitude function or the second light amplitude function to the first light amplitude function, the first amplitude ratio function about the light amplitude ratio and the modulation light frequency as Figure 6 shown can be obtained; the second light signal processing module 42 can obtain the light amplitude functions of the third output light signal and the fourth output light signal, and based on the ratio of the third light amplitude function to the fourth light amplitude function or the fourth light amplitude function to the third light amplitude function, the second amplitude ratio function about the light amplitude ratio and the modulation light frequency as Figure 7 shown can be obtained. It can be seen that the slope of the first amplitude ratio function is greater than the slope of the second amplitude ratio function, and the period of the first amplitude ratio function is smaller than the period of the second amplitude ratio function; then, as Figure 8As shown, by combining the first amplitude ratio function and the second amplitude ratio function, after the optical amplitudes of the first, second, third and fourth output optical signals are measured, the modulation optical frequency can be obtained in any interval where the frequency has a unique solution, and then the external microwave signal frequency is obtained, so that the frequency calculation accuracy of the example can reach the calculation accuracy of the first amplitude ratio function, the frequency calculation bandwidth is expanded to one half of the least common multiple period of the first amplitude ratio function and the second amplitude ratio function, and the large bandwidth and high precision measurement effect of the application is realized. Furthermore, since the starting point of the interval where the frequency has a unique solution can be set according to the actual needs of the technicians, in principle, the application can measure the frequency of the external microwave signal in the full frequency band, so it also has strong application value.

[0069] It needs to be further explained that, as Figure 9 As shown, when n is 3, the optical signal processing module 4 includes a first optical signal processing unit, a second optical signal processing unit and a third optical signal processing unit, and the photoelectric detection module 5 includes a first photoelectric detection unit, a second photoelectric detection unit and a third photoelectric detection unit (one photoelectric detection unit includes two photoelectric detectors), so that the microwave frequency measurement device of the example obtains three amplitude ratio functions. Further, the slope of the first amplitude ratio function is greater than the slope of the second amplitude ratio function, which is greater than the slope of the third amplitude ratio function, and the frequency period of the first amplitude ratio function is smaller than the frequency period of the second amplitude ratio function, which is smaller than the frequency period of the third amplitude ratio function. Furthermore, by combining the three amplitude ratio functions, the frequency of the modulation optical signal is obtained in any interval where the frequency has a unique solution, and the frequency of the external microwave signal is obtained, so that the application purpose of large bandwidth and high precision measurement of the application is realized.

[0070] Embodiment Two

[0071] As Figure 10 As shown, the embodiment provides a microwave frequency measurement device, and the difference between the embodiment and the embodiment one is that the electro-optical modulation module 3 is formed on the photonic integrated platform 6.

[0072] Specifically, in the embodiment, when the optical signal processing module 4 is prepared on the photonic integrated platform 6, the electro-optical modulation module 3 is also integrated on the photonic integrated platform 6. Further, the light source 1 is also integrated on the photonic integrated platform 6, so that the integration degree of the microwave frequency measurement device is higher.

[0073] Embodiment Three

[0074] As Figure 11 As shown, the embodiment provides a microwave frequency measurement device, and the difference between the embodiment and the embodiment one is that the electro-optical modulation module 3 is formed on the photonic integrated platform 6.

[0075] Specifically, in the present embodiment, when the optical signal processing module 3 is prepared on the photonic integrated platform 6, the photodetector module 5 is also integrated on the photonic integrated platform 6, so as to improve the integration of the microwave frequency measurement device. Further, the light source 1, the electro-optical modulation module 3, the optical signal processing module 4, and the photodetector module 5 can all be integrated on the photonic integrated platform 6, and then the microwave receiving module 2 is connected with the electro-optical modulation module 3 on the photonic integrated platform 6, so that the microwave frequency measurement device is used as a whole, and the demand for large-scale optoelectronic integration is met.

[0076] Embodiment Four

[0077] As shown in Figure 11 , the present embodiment provides a microwave frequency measurement method, comprising the following steps:

[0078] As shown in Figure 11 , in step S1, a laser signal and an external microwave signal to be measured are provided; the external microwave signal is modulated on the laser signal to generate a modulated light signal; the modulated light signal is divided into n optical signals, each of which generates 2 output light signals, 1 amplitude ratio function is established based on 2 output light signals of 1 optical signal, and n amplitude ratio functions are obtained, the slopes of the n amplitude ratio functions decrease and the frequency periods increase; wherein n is a natural number greater than or equal to 2, and the amplitude ratio function is a periodic function about the optical amplitude ratio and the optical signal frequency.

[0079] Specifically, in the present embodiment, the frequency of the modulated light signal is determined by the frequency of the external microwave signal and the frequency of the laser signal, and since the frequency of the laser signal is known, the frequency of the external microwave signal can be obtained by measuring the frequency of the modulated light signal. Further, the 2n output light signals obtain n amplitude ratio functions, the slopes of the n amplitude ratio functions decrease and the frequency periods increase, wherein the amplitude ratio function is a periodic function about the optical amplitude ratio (dependent variable) and the modulated light signal frequency (independent variable), and the slope of the amplitude ratio function refers to the slope between the maximum value and the minimum value of the amplitude ratio function in one period. Further, the frequency characteristics of the 2n output light signals are the same and consistent with the frequency characteristics of the modulated light signal, so the n amplitude ratio functions can be solved simultaneously at the same frequency to obtain the frequency of the modulated light signal.

[0080] As shown in Figure 12 , in step S2, the n amplitude ratio functions are solved simultaneously, the frequency of the modulated light signal is obtained in the interval where there is a unique frequency solution, and the frequency of the external microwave signal is obtained based on the frequency of the modulated light signal.

[0081] Specifically, in the embodiment, one optical amplitude function is established based on the optical amplitude and frequency of one of the two output optical signals of the one optical signal, another optical amplitude function is established based on the optical amplitude and frequency of the other output optical signal, and thus a corresponding amplitude ratio function is established based on the ratio of the pair of optical amplitude functions, and thus n amplitude ratio functions can be obtained from 2n output optical signals. As an example, n is 2, a first optical amplitude function and a second optical amplitude function of a first output optical signal and a second output optical signal are respectively established, and a first amplitude ratio function about the optical amplitude ratio and the modulated light frequency is established based on the ratio of the first optical amplitude function and the second optical amplitude function (the first optical amplitude function is greater than the second optical amplitude function or the second optical amplitude function is greater than the first optical amplitude function); a third optical amplitude function and a fourth optical amplitude function of a third output optical signal and a fourth output optical signal are respectively established, and a second amplitude ratio function about the optical amplitude ratio and the modulated light frequency is established based on the ratio of the third optical amplitude function and the fourth optical amplitude function (the third optical amplitude function is greater than the fourth optical amplitude function or the fourth optical amplitude function is greater than the third optical amplitude function), and it can be seen that the slope of the first amplitude ratio function is greater than the slope of the second amplitude ratio function, and the period of the first amplitude ratio function is smaller than the period of the second amplitude ratio function. Further, the modulated light frequency is obtained through the amplitude ratio function, which can better exclude the influence of power change on the measurement result, and the anti-interference ability of the measurement result is stronger. Further, the frequency of the modulated light signal is obtained in any interval where the frequency has a unique solution by simultaneously solving the first and second amplitude ratio functions, and the frequency of the external microwave signal is further obtained, and the calculation accuracy is expanded to the accuracy of the first amplitude ratio function, and the calculation bandwidth is expanded to one half of the least common multiple period of the first and second amplitude ratio functions, so that the measurement purpose of large bandwidth and high accuracy of the application is achieved. In actual application, n is valued as needed, and the embodiment is not limited.

[0082] Specifically, in the embodiment, as shown in Figure 12 the interval where the frequency has a unique solution, (A, B, …, N) corresponds to the unique frequency f of the modulated light signal, where A represents the optical amplitude ratio of the first amplitude ratio function, B represents the optical amplitude ratio of the second amplitude ratio function, and N represents the optical amplitude ratio of the nth amplitude ratio function. Further, when the frequency interval is less than or equal to one half of the least common multiple period, it can be ensured that the frequency has a unique solution, and the least common multiple period is the least common multiple of the frequency periods of the first amplitude ratio function, the second amplitude ratio function, …, and the nth amplitude ratio function. As an example, n is 2, the frequency period of the first amplitude ratio function is T, and the frequency period of the second amplitude ratio function is 6T, and thus Figure 10The frequency f obtained by the A value and the B value in the simultaneous equations is unique in the frequency interval of 3T, ensuring that the unique solution of the modulation light frequency can be obtained; further, the second amplitude ratio function is also monotonic in the interval as shown ​ The interval shown is also monotonic, which can further ensure that the frequency solution obtained is unique, so the solving bandwidth of the modulation light signal can be expanded to one half of the least common multiple period. In actual application, the specific frequency period of each amplitude ratio function is set according to actual needs, and the interval in which the frequency unique solution exists is selected, which is not limited to the embodiment.

[0083] It should be noted that the microwave frequency measurement method of the embodiment can be implemented based on the microwave frequency measurement devices of embodiments one to three, and can also be implemented based on other microwave frequency measurement devices, which is not specifically limited here.

[0084] In summary, the microwave frequency measurement device and method of the present application include a light source, a microwave receiving module, an electro-optical modulation module, an optical signal processing module, a photoelectric detection module, and a photonic integrated platform. The light source is used to generate a laser signal, the microwave receiving module is used to receive an external microwave signal, the electro-optical modulation module modulates the external microwave signal onto the laser signal and generates a modulation light signal; the modulation light signal passes through n optical signal processing units of the optical signal processing module on the photonic integrated platform to generate 2n output optical signals, which are converted into corresponding electrical signals by the photoelectric detection module; an amplitude ratio function is established based on two output optical signals of one optical signal processing unit, so that n amplitude ratio functions can be obtained; the frequency of the modulation light signal is obtained in any interval where the frequency unique solution exists by simultaneously solving the n amplitude ratio functions, and the frequency of the external microwave signal is obtained. The present application has the advantages of fast and real-time measurement of the frequency of the microwave signal in a very wide bandwidth range, and also has the inherent low loss and anti-electromagnetic interference advantages of photonic technology. Therefore, the present application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0085] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A microwave frequency measuring device, characterized in that: The microwave frequency measurement device at least includes: a light source, a microwave receiving module, an electro-optical modulation module, an optical signal processing module, a photoelectric detection module and a photon integration platform; The light source is used to generate a laser signal; The microwave receiving module is used to receive external microwave signals; The electro-optical modulation module receives the laser signal based on the optical input port, receives the external microwave signal based on the electrical input port, and modulates the external microwave signal onto the laser signal to generate a modulated optical signal; The optical signal processing module is formed on the photonic integrated platform; the optical signal processing module receives the modulated optical signal and divides the modulated optical signal into n parts; the optical signal processing module includes n optical signal processing units, the n optical signal processing units receive the n modulated optical signals in a one-to-one correspondence, and each optical signal processing unit generates two output optical signals; n is a natural number greater than or equal to 2; The photoelectric detection module is used to convert the optical signal into an electrical signal; the photoelectric detection module includes n photoelectric detection units, each of which corresponds to the optical signal processing unit on a one-to-one basis and receives two output optical signals of the optical signal processing unit; In which, n amplitude ratio functions are established based on the output optical signals of each of the n optical signal processing units, the slopes of the n amplitude ratio functions decreasing and the frequency periods increasing, and the amplitude ratio functions are periodic functions of the optical amplitude ratio and the optical signal frequency; the n amplitude ratio functions are combined to obtain the frequency of the modulated optical signal within any interval for which a unique frequency solution exists, thereby obtaining the frequency of the external microwave signal.

2. The microwave frequency measuring device according to claim 1, characterized in that: The value of n is 2; the optical signal processing module includes a first optical signal processing unit and a second optical signal processing unit; the photoelectric detection module includes a first photoelectric detection unit and a second photoelectric detection unit; The first optical signal processing unit outputs first and second output optical signals, and the second optical signal processing unit outputs third and fourth output optical signals; The first photodetection unit receives the first and second output light signals, and the second photodetection unit receives the third and fourth output light signals.

3. The microwave frequency measuring device according to claim 2, characterized in that: The first optical signal processing unit includes a first bus waveguide, a first microring waveguide and a second bus waveguide; The first bus waveguide receives a corresponding modulated optical signal, and is used to couple a portion of the modulated optical signal to the first microring waveguide, and use another portion of the modulated optical signal as the first output optical signal; The first microring waveguide receives a portion of the modulated optical signal and couples to the second bus waveguide; The second bus waveguide receives the optical signal transmitted by the first microring waveguide and outputs the second output optical signal.

4. The microwave frequency measuring device according to claim 2, wherein: The second optical signal processing unit is a Mach-Zehnder interferometer.

5. The microwave frequency measuring device according to claim 2, characterized in that: The second optical signal processing unit includes a third bus waveguide, a second microring waveguide and a fourth bus waveguide; The third bus waveguide receives the corresponding modulated optical signal, and is used to couple part of the modulated optical signal to the second microring waveguide, and use another part of the modulated optical signal as the third output optical signal; The second microring waveguide receives a portion of the modulated optical signal and is coupled to the fourth bus waveguide; The fourth bus waveguide receives the optical signal transmitted by the second microring waveguide and outputs the fourth output optical signal.

6. The microwave frequency measuring device according to claim 1, characterized in that: The electro-optical modulation module is formed on the photonic integration platform.

7. The microwave frequency measuring device according to claim 5, characterized in that: The light source is formed on the photonic integration platform.

8. The microwave frequency measuring device according to claim 1, characterized in that: The first and second photoelectric detection modules are formed on the photonic integration platform.

9. A microwave frequency measurement method, characterized in that: The microwave frequency measurement method comprises at least the following steps: S1: providing a laser signal and an external microwave signal to be measured; modulating the external microwave signal on the laser signal to generate a modulated optical signal; dividing the modulated optical signal into n optical signals, each optical signal generating two output optical signals, establishing an amplitude ratio function based on the two output optical signals of one optical signal and obtaining n amplitude ratio functions, wherein the slopes of the n amplitude ratio functions decrease and the frequency periods increase; wherein n is a natural number greater than or equal to 2, and the amplitude ratio function is a periodic function of the optical amplitude ratio and the optical signal frequency; S2: Simultaneously performing n amplitude ratio functions, obtaining the frequency of the modulated optical signal within a range where a unique frequency solution exists, and obtaining the frequency of the external microwave signal based on the frequency of the modulated optical signal; The frequency characteristics of the 2n output optical signals are the same and consistent with the frequency characteristics of the modulated optical signal.

10. The microwave frequency measurement method according to claim 8, characterized in that: In step S1, among the two output optical signals of one optical signal, an optical amplitude function is established based on the optical amplitude and frequency of one output optical signal, and another optical amplitude function is established based on the optical amplitude and frequency of the other output optical signal; and a corresponding amplitude ratio function is established based on the ratio of a pair of optical amplitude functions.

11. The microwave frequency measurement method according to claim 8, wherein: In step S2, the least common multiple frequency period of the n amplitude ratio functions is obtained, and the length of the interval in which the unique frequency solution exists is less than or equal to half of the least common multiple frequency period.

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