Double-loop sapphire oscillation system

Abstract

The embodiment of the invention discloses a double-loop sapphire oscillation system, and the system comprises a sapphire microwave cavity which is used for carrying out the oscillation of a first microwave signal to obtain a second microwave signal, and carrying out the oscillation of a third microwave signal to obtain a fourth microwave signal; the temperature device is used for providing a working environment for the sapphire microwave cavity; the coupling module is used for coupling the second microwave signal to the first oscillation circuit, coupling the fourth microwave signal to the second oscillation circuit and feeding the first microwave signal and the second microwave signal into the sapphire microwave cavity; the first oscillation circuit is used for obtaining a first microwave signal according to the first input signal and working in a first working mode after oscillation starting according to the first control signal; the second oscillation circuit is used for obtaining a second microwave signal according to a second input signal and working in a second working mode after oscillation starting according to a second control signal; and the frequency mixing module is used for mixing the third microwave signal and the fourth microwave signal to obtain a target microwave signal.

Description

Technical Field

[0001] This invention relates to the field of electronic equipment technology. More specifically, it relates to a dual-loop sapphire oscillation system. Background Technology

[0002] Currently, low-phase-noise, high-stability microwave frequency sources are widely used in radar, communications, aerospace, metrology, and fundamental physics research. There are two main methods for obtaining microwave sources: Method 1, the traditional method of frequency doubling using a standard crystal oscillator (5MHz or 10MHz); and Method 2, obtaining the microwave source by designing the resonant frequency of a dielectric oscillator (DRO) and using external circuitry. Compared to these two traditional methods, the low-temperature sapphire microwave frequency source exhibits extremely low phase noise (<-160dBc / Hz@10kHz in the X-band) and excellent short-term stability (<1E-15@1s), far exceeding the performance of traditional microwave sources. Its main working principle is as follows: utilizing the low-loss tangent of sapphire at low temperatures, a high-Q microwave is generated. Positive excitation is used to cause the high-Q microwave cavity to oscillate at a selected frequency. Phase and amplitude control of this microwave frequency are performed in the external circuitry, resulting in a stable microwave signal output.

[0003] Existing technologies have achieved excellent performance indicators of 5E-16@1s stability and -100dBc / Hz@1Hz using low-temperature sapphire. Existing technologies have also achieved 1E-15τ stability using low-temperature sapphire. -1 / 2 (1s < τ < 10s), with a phase noise of -97.5dBc / Hz at 1Hz. A low-temperature sapphire microwave frequency source with an output frequency of 9.2GHz has also been developed domestically. Because the dielectric constant and paramagnetism of sapphire crystals are both temperature-sensitive, the resonant frequency of the sapphire microwave cavity is also temperature-sensitive.

[0004] In the operation of sapphire oscillators, precise temperature control of the microwave cavity is typically required to minimize the impact of temperature fluctuations on the frequency stability of the oscillator's output signal. Simultaneously, experimental methods are used to determine the operating temperature point where the resonant frequency of the microwave cavity is least sensitive to temperature. However, the accuracy of temperature control remains limited, and the microwave cavity is relatively large. Existing methods typically aim to stabilize the temperature at a specific location on the top cover of the microwave cavity, which results in a temperature gradient across the entire cavity. Furthermore, the experimentally determined operating temperature point does not necessarily optimize the Q-value of the microwave cavity. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-loop sapphire oscillation system to solve at least one of the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present application provides a double-loop sapphire oscillation system, comprising: a sapphire microwave cavity, configured to oscillate a first microwave signal to obtain a second microwave signal and oscillate a third microwave signal to obtain a fourth microwave signal; a temperature device, configured to provide a working environment for the sapphire microwave cavity; a coupling module, configured to couple the second microwave signal to a first oscillation loop, couple the fourth microwave signal to a second oscillation loop, and feed the first microwave signal and the second microwave signal into the sapphire microwave cavity; the first oscillation loop, configured to obtain the first microwave signal according to a first input signal and work in a first working mode after starting oscillation according to a first control signal; the second oscillation loop, configured to obtain the second microwave signal according to a second input signal and work in a second working mode after starting oscillation according to a second control signal; a mixing module, configured to mix the third microwave signal and the fourth microwave signal to obtain a target microwave signal.

[0007] Optionally, the sapphire microwave cavity is arranged in the temperature device. The coupling module is arranged on the sapphire microwave cavity. A first output end of the coupling module is connected with a first input end of the first oscillation loop, a second output end of the coupling module is connected with a first input end of the second oscillation loop, and an input end of the coupling module is connected with a first output end of the first oscillation loop and a first output end of the second oscillation loop. A second input end of the first oscillation loop receives the first input signal, a third input end of the first oscillation loop receives the first control signal, and a second output end of the first oscillation loop is connected with a first input end of the mixing module. A second input end of the second oscillation loop receives the second input signal, a third input end of the second oscillation loop receives the second control signal, and a second output end of the second oscillation loop is connected with a second input end of the mixing module. An output end of the mixing module outputs the target microwave signal.

[0008] Optionally, the system further comprises a combining module. A first input end of the combining module is connected with a first output end of the first oscillation loop. A second input end of the combining module is connected with a first output end of the second oscillation loop. An output end of the combining module is connected with an input end of the coupling module.

[0009] Optionally, the coupling module comprises a first coupler, a second coupler and a third coupler; The input end of the first coupler receives the second microwave signal, and the output end of the first coupler is connected with the first input end of the first oscillation loop; The input end of the second coupler receives the fourth microwave signal, and the output end of the second coupler is connected with the first input end of the second oscillation loop; The output end of the third coupler outputs the first microwave signal and the second microwave signal, and the input end of the third coupler is connected with the output end of the combining module.

[0010] Optionally, the first oscillation loop comprises a first band-pass filter, a first microwave amplifier, a first directional coupler and a first phase shifter; The input end of the first band-pass filter is connected with the output end of the first coupler, and the output end of the first band-pass filter is connected with the first input end of the first microwave amplifier; The second input end of the first microwave amplifier receives the first input signal, and the output end of the second microwave amplifier is connected with the input end of the first directional coupler; The first output end of the first directional coupler is connected with the first input end of the first phase shifter, and the second output end of the first directional coupler is connected with the first input end of the mixing module; The second input end of the first phase shifter receives the first control signal, and the output end of the first phase shifter is connected with the first input end of the combining module.

[0011] Optionally, the second oscillation loop comprises a second band-pass filter, a second microwave amplifier, a second directional coupler and a second phase shifter; The input end of the second band-pass filter is connected with the output end of the second coupler, and the output end of the second band-pass filter is connected with the first input end of the second microwave amplifier; The second input end of the second microwave amplifier receives the second input signal, and the output end of the second microwave amplifier is connected with the input end of the second directional coupler; The first output end of the second directional coupler is connected with the first input end of the second phase shifter, and the second output end of the second directional coupler is connected with the second input end of the mixing module; The second input end of the second phase shifter receives the second control signal, and the output end of the second phase shifter is connected with the second input end of the combining module.

[0012] Optionally, the working frequency of the first working mode ranges from 12GHz to 12.2GHz. The quality factor of the first working mode ranges from 1.1E9 to 1.3E9.

[0013] Optionally, the working frequency of the second working mode ranges from 9.7GHz to 9.9GHz. The quality factor of the second working mode ranges from 9.2E8 to 9.4E8.

[0014] Optionally, the amplification gain of the first microwave amplifier ranges from 34dB to 36dB. The amplification gain of the second microwave amplifier ranges from 34dB to 36dB.

[0015] Optionally, the frequency of the target microwave signal ranges from 2.2GHz to 2.4GHz. The second stability of the target microwave signal ranges from 8E-16 to 1E-17.

[0016] The beneficial effects of the present application are as follows: The technical scheme of the present application can greatly reduce the influence of temperature and temperature jitter on the frequency stability of the oscillator, thereby obtaining a high-frequency stability microwave signal. BRIEF DESCRIPTION OF DRAWINGS

[0017] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0018] Figure 1 A schematic diagram of a double-loop sapphire oscillation system is shown. DETAILED DESCRIPTION

[0019] In order to more clearly illustrate the present application, the present application will be further described below with reference to the embodiments and the accompanying drawings. Similar components are denoted by the same reference numerals in the drawings. Those skilled in the art should understand that the specific description below is illustrative rather than limiting, and should not limit the protection scope of the present application.

[0020] Generally, in the process of the sapphire oscillator, in order to reduce the influence of temperature fluctuation on the frequency stability of the oscillator output signal, the microwave cavity needs to be precisely temperature-controlled, and the working temperature point of the microwave cavity at which the resonance frequency is least sensitive to temperature is obtained through experiments. However, the temperature control precision is still limited, and the microwave cavity is relatively large, and the existing method is to stably control the temperature at a certain position on the top cover of the microwave cavity, which causes a temperature gradient in the whole microwave cavity. Moreover, the working temperature point determined by experiments cannot make the Q value of the microwave cavity reach the optimal value.

[0021] Therefore, one embodiment of the present application provides a double-loop sapphire oscillator system, which comprises: a sapphire microwave cavity 1 for oscillating a first microwave signal to obtain a second microwave signal and oscillating a third microwave signal to obtain a fourth microwave signal; a temperature device (for example, a low-temperature device 2) for providing a working environment for the sapphire microwave cavity; a coupling module for coupling the second microwave signal to a first oscillation loop and coupling the fourth microwave signal to a second oscillation loop, and feeding the first microwave signal and the second microwave signal into the sapphire microwave cavity; a first oscillation loop for obtaining the first microwave signal according to a first input signal and working in a first working mode after starting oscillation according to a first control signal; a second oscillation loop for obtaining the second microwave signal according to a second input signal and working in a second working mode after starting oscillation according to a second control signal; and a mixing module (for example, a mixer 15) for mixing the third microwave signal and the fourth microwave signal to obtain a target microwave signal.

[0022] In one specific example, a sapphire microwave cavity working in the whispering gallery mode is used to construct two oscillation loops, one working in the E mode and the other working in the H mode, and the output frequencies of the two oscillation loops are different, and the difference frequency signal is the output signal of the entire oscillator. Since the same microwave cavity is used to generate two oscillation loops, the influence of temperature change on their frequencies is basically the same, the output signals of the two oscillation loops are mixed, and the temperature influence on the frequency will be offset, and the frequency stability of the difference frequency signal will not be affected by temperature fluctuation.

[0023] Since the sapphire microwave cavity working in the high-order whispering gallery mode is sensitive to temperature, the use of the two-loop difference frequency signal as the final output signal can greatly reduce the influence of temperature and temperature jitter on the frequency stability of the oscillator, thereby obtaining a microwave signal with high frequency stability.

[0024] In a possible implementation, the sapphire microwave cavity is arranged in the temperature device; the coupling module is arranged on the sapphire microwave cavity; a first output end of the coupling module is connected with a first input end of the first oscillation loop, a second output end of the coupling module is connected with a first input end of the second oscillation loop, and an input end of the coupling module is connected with a first output end of the first oscillation loop and a first output end of the second oscillation loop; a second input end of the first oscillation loop receives the first input signal, a third input end of the first oscillation loop receives the first control signal, and a second output end of the first oscillation loop is connected with a first input end of the mixing module; a second input end of the second oscillation loop receives the second input signal, a third input end of the second oscillation loop receives the second control signal, and a second output end of the second oscillation loop is connected with a second input end of the mixing module; and an output end of the mixing module outputs the target microwave signal.

[0025] In a possible implementation, the system further includes a combining module (for example, the combiner 10); a first input end of the combining module is connected with a first output end of the first oscillation loop; a second input end of the combining module is connected with a first output end of the second oscillation loop; and an output end of the combining module is connected with an input end of the coupling module.

[0026] In a possible implementation, the coupling module includes a first coupler 3, a second coupler 4, and a third coupler 5; an input end of the first coupler receives the second microwave signal, and an output end of the first coupler is connected with a first input end of the first oscillation loop; an input end of the second coupler receives the fourth microwave signal, and an output end of the second coupler is connected with a first input end of the second oscillation loop; an output end of the third coupler outputs the first microwave signal and the second microwave signal, and an input end of the third coupler is connected with an output end of the combining module.

[0027] In a possible implementation, the first oscillation loop includes a first band-pass filter 6, a first microwave amplifier 7, a first directional coupler 8, and a first phase shifter 9; an input end of the first band-pass filter is connected with an output end of the first coupler, an output end of the first band-pass filter is connected with a first input end of the first microwave amplifier; a second input end of the first microwave amplifier receives the first input signal, an output end of the second microwave amplifier is connected with an input end of the first directional coupler; a first output end of the first directional coupler is connected with a first input end of the first phase shifter, a second output end of the first directional coupler is connected with a first input end of the mixing module; a second input end of the first phase shifter receives the first control signal, an output end of the first phase shifter is connected with a first input end of the combining module.

[0028] In a possible implementation, the second oscillation loop includes a second band-pass filter 11, a second microwave amplifier 12, a second directional coupler 13, and a second phase shifter 14; an input end of the second band-pass filter is connected with an output end of the second coupler, an output end of the second band-pass filter is connected with a first input end of the second microwave amplifier; a second input end of the second microwave amplifier receives the second input signal, an output end of the second microwave amplifier is connected with an input end of the second directional coupler; a first output end of the second directional coupler is connected with a first input end of the second phase shifter, a second output end of the second directional coupler is connected with a second input end of the mixing module; a second input end of the second phase shifter receives the second control signal, an output end of the second phase shifter is connected with a second input end of the combining module.

[0029] In a specific example, as shown in FIG. 1, the low-temperature device 2 provides a low-temperature working environment for the sapphire microwave cavity 1, and there are three couplers in the microwave cavity, wherein the couplers 3 and 4 located on the side wall of the microwave cavity are coupling loops for magnetic field coupling, and the coupler 5 located on the cover of the microwave cavity is a coupling probe for electric field coupling. Figure 1

[0030] In a specific example, the first oscillation loop: the coupler 3 is used to couple the microwave signal out of the cavity, and the microwave signal is connected out of the low-temperature device 2 through a microwave cable and connected with the band-pass filter 6, the band-pass filter 6 is connected with the microwave amplifier 7, the microwave amplifier 7 is connected with the directional coupler 8, one of the outputs of the directional coupler 8 is connected with the phase shifter 9, the other output of the directional coupler 8 is connected with the input port of the mixer 15, the phase shifter 9 is connected with the combiner 10, and the output port of the combiner 10 is connected with the coupler 4 in the low-temperature device 2 through a cable to feed the microwave signal into the sapphire microwave cavity.

[0031] ​In a specific example, the second oscillation loop: the coupler 5 is used to couple the microwave signal out of the cavity, through the microwave cable connected out of the cryogenic device 2, and connected with the band-pass filter 11, the band-pass filter 11 is connected with the microwave amplifier 12, the microwave amplifier 12 is connected with the directional coupler 13, one of the outputs of the directional coupler 13 is connected with the phase shifter 14, the other output of the directional coupler 13 is connected with the input port of the mixer 15, and the phase shifter 14 is connected with the other input port of the combiner 10, to feed the microwave signal into the sapphire microwave cavity. After the first oscillation loop and the second oscillation loop are respectively started, the mixer 15 outputs the difference frequency signal of the two oscillation signals, which is the final output signal of the double-loop sapphire oscillator.

[0032] In a specific example, before the oscillator works, the cryogenic device needs to be started and wait for it to reach a stable working state, and the selected working temperature point is the temperature value when the Q value is optimal. This value is determined according to experiments, and is usually around 4.2K.

[0033] In a specific example, the working frequency of the microwave devices in the two oscillation loops needs to cover the oscillation frequency of the loop respectively. The phase values of the phase shifter 9 and the phase shifter 14 (for example, the first control signal and the second control signal) are adjusted to make the two loops start oscillation respectively. Among them, the first oscillation loop uses a magnetic loop coupler, and the working whispering gallery mode is E mode. The second oscillation loop uses a probe coupler and a magnetic loop coupler, and the working whispering gallery mode is H mode. The frequency difference exists between the two mode frequencies, and the difference frequency signal is the final oscillator output signal.

[0034] In a specific example, the sensitivity coefficient of the resonant frequency to the temperature is:

[0035] Among them, is the resonant frequency at the reference temperature; is the frequency change amount; is the temperature change amount; is the electric field filling factor perpendicular to the crystal axis direction; is the electric field filling factor parallel to the crystal axis direction; is the sensitivity of the resonant frequency to the diameter change; is the sensitivity of the resonant frequency to the height change; is the dielectric constant-temperature sensitivity of sapphire perpendicular to the crystal axis direction; is the dielectric constant-temperature sensitivity of sapphire parallel to the crystal axis direction; is the thermal expansion coefficient of the crystal along the diameter direction; is the thermal expansion coefficient of the crystal along the height direction.

[0036] In a specific example, when the ambient temperature fluctuates, the output frequencies of the two oscillation loops fluctuate synchronously, the difference frequency signal fluctuation value is greatly reduced, and it has excellent frequency stability performance.

[0037] In one possible implementation, the operating frequency of the first operating mode is in the range of 12GHz to 12.2GHz; and the quality factor of the first operating mode is in the range of 1.1E9 to 1.3E9.

[0038] In one possible implementation, the operating frequency of the second operating mode is in the range of 9.7 GHz to 9.9 GHz; and the quality factor of the second operating mode is in the range of 9.2E8 to 9.4E8.

[0039] In one possible implementation, the amplification gain of the first microwave amplifier is in the range of 34dB to 36dB; the amplification gain of the second microwave amplifier is in the range of 34dB to 36dB.

[0040] In one possible implementation, the frequency of the target microwave signal ranges from 2.2 GHz to 2.4 GHz; the second stability of the target microwave signal ranges from 8E-16 to 1E-17.

[0041] In a specific example, the connection of the sapphire microwave cavity, cryogenic device, and microwave components is completed. Based on the Q-value test results, the operating temperature of the sapphire microwave cavity is selected as 4.2K, at which the Q-value of the sapphire microwave cavity is the highest.

[0042] In a specific example, for the first oscillation loop, the E-mode operating frequency is selected as 12.1 GHz, and the Q value reaches 1.2E9. The operating frequencies of the selected microwave devices, including bandpass filter 6, microwave amplifier 7, directional coupler 8, phase shifter 9, combiner 10, and mixer 15, all cover 12.1 GHz.

[0043] In a specific example, for the second oscillation loop, the operating frequency of the H mode is selected to be 9.8 GHz, with a Q value of 9.3E8. The operating frequencies of the selected microwave devices, including the bandpass filter 11, microwave amplifier 12, directional coupler 13, phase shifter 14, combiner 10, and mixer 15, all cover 9.8 GHz.

[0044] In a specific example, the microwave amplifier gain in the oscillation loop is 35dB. The phase shifter parameters are adjusted to make the loop meet the oscillation start-up conditions. The phase shifter parameters of the two loops are adjusted separately to make the loop oscillate in the selected whispering gallery mode.

[0045] In a specific example, the final output signal is 2.3GHz, and the frequency stability test shows a stability of 9E-16 per second.

[0046] In the description of the present application, it should be noted that the terms "upper", "lower", and the like are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise expressly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] It should also be noted that in the description of the present application, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without more limitation, the element defined by the sentence "including a…" does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0048] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not limitations on the embodiments of the present application. For those of ordinary skill in the art, other different forms of changes or variations can be made on the basis of the above description, and it is impossible to enumerate all the embodiments here. Any obvious changes or variations derived from the technical solutions of the present application are still within the protection scope of the present application.

Claims

1. A dual loop sapphire oscillation system, characterized by, The system comprises: a sapphire microwave cavity, configured to oscillate a first microwave signal to obtain a second microwave signal and oscillate a third microwave signal to obtain a fourth microwave signal; a temperature device, configured to provide a working environment for the sapphire microwave cavity; a coupling module, configured to couple the second microwave signal to a first oscillation loop, couple the fourth microwave signal to a second oscillation loop, and feed the first microwave signal and the second microwave signal into the sapphire microwave cavity; the first oscillation loop, configured to obtain the first microwave signal according to a first input signal and work in a first working mode after starting oscillation according to a first control signal; the second oscillation loop, configured to obtain the second microwave signal according to a second input signal and work in a second working mode after starting oscillation according to a second control signal; a mixing module, configured to mix the third microwave signal and the fourth microwave signal to obtain a target microwave signal.

2. The dual-loop sapphire oscillation system according to claim 1, wherein: the sapphire microwave cavity is arranged in the temperature device; the coupling module is arranged on the sapphire microwave cavity; a first output end of the coupling module is connected with a first input end of the first oscillation loop, a second output end of the coupling module is connected with a first input end of the second oscillation loop, and an input end of the coupling module is connected with a first output end of the first oscillation loop and a first output end of the second oscillation loop; a second input end of the first oscillation loop receives the first input signal, a third input end of the first oscillation loop receives the first control signal, and a second output end of the first oscillation loop is connected with a first input end of the mixing module; a second input end of the second oscillation loop receives the second input signal, a third input end of the second oscillation loop receives the second control signal, and a second output end of the second oscillation loop is connected with a second input end of the mixing module; an output end of the mixing module outputs the target microwave signal.

3. The dual loop sapphire oscillation system of claim 2, wherein, The system further comprises a combining module; a first input end of the combining module is connected with a first output end of the first oscillation loop; a second input end of the combining module is connected with a first output end of the second oscillation loop; an output end of the combining module is connected with an input end of the coupling module.

4. The dual-loop sapphire oscillation system according to claim 3, wherein: the coupling module comprises a first coupler, a second coupler and a third coupler; an input end of the first coupler receives the second microwave signal, and an output end of the first coupler is connected with a first input end of the first oscillation loop; an input end of the second coupler receives the fourth microwave signal, and an output end of the second coupler is connected with a first input end of the second oscillation loop; an output end of the third coupler outputs the first microwave signal and the second microwave signal, and an input end of the third coupler is connected with an output end of the combining module.

5. The dual-loop sapphire oscillation system according to claim 4, wherein: The first oscillation circuit comprises a first band-pass filter, a first microwave amplifier, a first directional coupler and a first phase shifter; The input end of the first band-pass filter is connected with the output end of the first coupler, and the output end of the first band-pass filter is connected with the first input end of the first microwave amplifier; The second input end of the first microwave amplifier receives the first input signal, and the output end of the second microwave amplifier is connected with the input end of the first directional coupler; The first output end of the first directional coupler is connected with the first input end of the first phase shifter, and the second output end of the first directional coupler is connected with the first input end of the mixing module; The second input end of the first phase shifter receives the first control signal, and the output end of the first phase shifter is connected with the first input end of the combining module.

6. The dual-loop sapphire oscillation system according to claim 5, wherein, The second oscillation circuit comprises a second band-pass filter, a second microwave amplifier, a second directional coupler and a second phase shifter; The input end of the second band-pass filter is connected with the output end of the second coupler, and the output end of the second band-pass filter is connected with the first input end of the second microwave amplifier; The second input end of the second microwave amplifier receives the second input signal, and the output end of the second microwave amplifier is connected with the input end of the second directional coupler; The first output end of the second directional coupler is connected with the first input end of the second phase shifter, and the second output end of the second directional coupler is connected with the second input end of the mixing module; The second input end of the second phase shifter receives the second control signal, and the output end of the second phase shifter is connected with the second input end of the combining module.

7. The dual-loop sapphire oscillation system according to claim 6, wherein, The working frequency of the first working mode ranges from 12GHz to 12.2GHz; The quality factor of the first working mode ranges from 1.1E9 to 1.3E9.

8. The dual-loop sapphire oscillation system according to claim 7, wherein, The working frequency of the second working mode ranges from 9.7GHz to 9.9GHz; The quality factor of the second working mode ranges from 9.2E8 to 9.4E8.

9. The dual-loop sapphire oscillation system according to claim 8, wherein, The amplification gain of the first microwave amplifier ranges from 34dB to 36dB; The amplification gain of the second microwave amplifier ranges from 34dB to 36dB.

10. The dual-loop sapphire oscillation system according to claim 9, wherein, The frequency of the target microwave signal ranges from 2.2GHz to 2.4GHz; The second stability of the target microwave signal ranges from 8E-16 to 1E-17.

Images