CN110988474B - Spectrum measuring system - Google Patents
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Abstract
本申请公开了一种频谱测量系统。频谱测量系统包括：功率分配器、白噪声信号模块、与功率分配器连接的频域转换模块以及与频域转换模块连接的频域信号计算模块，并且其中功率分配器用于接收待检测信号和白噪声信号模块发送的白噪声信号，并且输出第一输出信号和第二输出信号；白噪声信号模块与功率分配器连接，用于以在第一白噪声信号和第二白噪声信号之间切换的方式，向功率分配器发送白噪声信号；频域转换模块用于将接收的第一输出信号和第二输出信号转换成相应的第一频域信号信息和第二频域信号信息；以及频域信号计算模块，用于对第一频域信号信息和第二频域信号信息进行相关运算，并根据相关运算的计算结果确定待检测信号的第一频谱信息。
The present application discloses a spectrum measurement system. The spectrum measurement system includes: a power divider, a white noise signal module, a frequency domain conversion module connected with the power divider, and a frequency domain signal calculation module connected with the frequency domain conversion module, and wherein the power divider is used for receiving the signal to be detected and the white noise. The white noise signal sent by the noise signal module, and outputs the first output signal and the second output signal; the white noise signal module is connected with the power divider, and is used for switching between the first white noise signal and the second white noise signal. The frequency domain conversion module is used to convert the received first output signal and the second output signal into corresponding first frequency domain signal information and second frequency domain signal information; and the frequency domain The signal calculation module is configured to perform a correlation operation on the first frequency domain signal information and the second frequency domain signal information, and determine the first spectrum information of the signal to be detected according to the calculation result of the correlation operation.
Description
Technical Field
The present application relates to the field of spectrum measurement technologies, and in particular, to a spectrum measurement system.
Background
Spectral measurement refers to measuring the frequency components of a signal in the frequency domain to obtain various parameters of the signal and parameters of the network through which the signal passes. The frequency spectrum measurement is widely applied to the fields of electronic system test measurement, radar signal analysis and the like. For some fields, the characteristics of the signal to be measured can be obtained by measuring the very fine variation of the signal to be measured on the background signal in the spectrum structure. For example, the whole-day spectrum (namely, a 21cm signal) measurement is carried out aiming at the universe dawn period (according to a universe evolution model, the universe evolution can be divided into a universe dark period, a universe dawn, a reionization period and a modern universe. Compared with the prospect of galaxy radiation and the like, the 21cm signal of the high-redshift universe is very weak, and the signal amplitude is about 5 orders of magnitude lower than that of the prospect, so that an ultra-high-precision spectrum measurement technology is needed. At present, components in an existing spectrum measurement system all have specific frequency response characteristics, different frequency points of the same component in a measured frequency band have different gains and phases, and the characteristics of the gains and the phases at the different frequency points are different for different components. At the output of the spectrum measurement system, the frequency response characteristics of the multiple components are summed, resulting in a measured spectrum with the band characteristics of the multiple components superimposed. In the existing spectrum measurement technology, a Dicke switch method is generally adopted to calibrate measured spectrum information, but the Dicke switch faces the influence of gain and system noise change in the switching process.
In view of the technical problems that in the existing spectrum measurement system in the prior art, the frequency response characteristic accumulation of each component can cause the frequency band characteristics of a plurality of components to be superimposed on the measured spectrum, and the change of system gain and noise can be caused by the switching of a Dicke switch in the process of calibrating the measured spectrum, an effective solution is not proposed at present.
Disclosure of Invention
The disclosure provides a spectrum measurement system, which at least solves the technical problems that in the existing spectrum measurement system in the prior art, the frequency response characteristic accumulation of each component can lead to the superposition of the frequency band characteristics of a plurality of components in a measured spectrum, and in the process of calibrating the measured spectrum by adopting a Dicke switch, the change of system gain and noise can be caused by the switching of the Dicke switch.
According to an aspect of the present application, there is provided a spectrum measurement system including: the power divider is used for receiving a signal to be detected and a white noise signal sent by the white noise signal module and outputting a first output signal and a second output signal, wherein the first output signal is a signal generated after the signal to be detected and the white noise signal are superposed, and the second output signal is a signal generated after an inverted signal of the signal to be detected and the white noise signal are superposed; the white noise signal module is connected with the power divider and used for sending a white noise signal to the power divider in a mode of switching between the first white noise signal and the second white noise signal; the frequency domain conversion module is used for converting the received first output signal and the second output signal into corresponding first frequency domain signal information and second frequency domain signal information; and the frequency domain signal calculation module is used for carrying out correlation operation on the first frequency domain signal information and the second frequency domain signal information and determining the first frequency spectrum information of the signal to be detected according to the calculation result of the correlation operation.
Therefore, according to the technical scheme of the application, the power divider is added in the frequency spectrum measuring system, and the signal is divided into two paths of equal-amplitude signals with opposite phases through the power divider. The white noise signal module is connected with the direct current power supply through the switch and sends different white noise signals to the power divider. The received first and second output signals are then converted into corresponding first and second frequency domain signal information by a frequency domain signal conversion module. And then, receiving the first frequency domain signal information and the second frequency domain signal information through a frequency domain signal calculation module, further calculating two kinds of signal spectrum information under different white noise signals, and further calculating the spectrum information of the signal to be detected according to the two kinds of signal spectrum information obtained by the frequency domain signal calculation module. Therefore, the power divider is added in the frequency spectrum measurement to change the single-path measurement in the previous frequency spectrum measurement system into the current two-path (the power divider is divided into two paths of signals with opposite phases) for simultaneous measurement, then the power comparison is carried out through the differential circuit (the differential circuit is formed under the two states of connection and disconnection of the white noise signal module 200 and a direct-connected power supply), the switch connected with the white noise signal module and the direct-current power supply is utilized to eliminate the mutual interference inside the system, and therefore the frequency band characteristic of a plurality of components superposed in the measured frequency spectrum due to the accumulation of the frequency response characteristics of the components in the frequency spectrum measurement system can be eliminated without using a Dicke switch, and the calibrated frequency spectrum information is obtained. The frequency response characteristic of each component is accumulated to result in that the frequency band characteristics of a plurality of components are superposed in the measured frequency spectrum in the existing frequency spectrum measuring system in the prior art, and the change of system gain and noise is caused by the switching of a Dicke switch in the process of calibrating the measured frequency spectrum by adopting the Dicke switch.
The above and other objects, advantages and features of the present application will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.
Drawings
Some specific embodiments of the present application will be described in detail hereinafter by way of illustration and not limitation with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:
FIG. 1 is a schematic diagram of a spectrum measurement system according to an embodiment of the present application;
FIG. 2 is a schematic diagram of the frequency domain signal conversion module shown in FIG. 1;
FIG. 3 is an exemplary schematic diagram of a spectrum measurement system according to an embodiment of the present application;
fig. 4A is a schematic diagram of spectrum information of a signal to be detected according to an embodiment of the present application;
FIG. 4B is a diagram illustrating spectrum information of an output frequency error of a spectrum measurement system according to an embodiment of the present application; and
fig. 4C is a schematic diagram of a spectrum information measured by the spectrum measurement system according to the embodiment of the present application drifting.
Detailed Description
It should be noted that, in the present disclosure, the embodiments and features of the embodiments may be combined with each other without conflict. The present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
In order to make the technical solutions of the present disclosure better understood by those skilled in the art, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only some embodiments of the present disclosure, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
It should be noted that the terms "first," "second," and the like in the description and claims of the present disclosure and in the above-described drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances for describing the embodiments of the disclosure herein. Furthermore, the terms "comprises," "comprising," and any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
Fig. 1 is a schematic diagram of a spectrum measurement system according to an embodiment of the present application, and referring to fig. 1, there is provided a spectrum measurement system 10 including: the power divider 100, the white noise signal module 200, the frequency domain conversion module 300 connected to the power divider 100, and the frequency domain signal calculation module 400 connected to the frequency domain conversion module 300, wherein the power divider 100 is configured to receive a signal to be detected and a white noise signal sent by the white noise signal module 200, and output a first output signal and a second output signal, wherein the first output signal is a signal generated after the signal to be detected and the white noise signal are superimposed, and the second output signal is a signal generated after an inverted signal of the signal to be detected and the white noise signal are superimposed; the white noise signal module 200 is connected to the power divider 100, and configured to send a white noise signal to the power divider 100 in a manner of switching between a first white noise signal and a second white noise signal; the frequency domain converting module 300 is configured to convert the received first output signal and the second output signal into corresponding first frequency domain signal information and second frequency domain signal information; and a frequency domain signal calculation module 400, configured to perform correlation operation on the first frequency domain signal information and the second frequency domain signal information, and determine the first frequency spectrum information of the signal to be detected according to a calculation result of the correlation operation.
Specifically, referring to fig. 1, the spectrum measuring system 10 includes: the power divider 100, the white noise signal module 200, the frequency domain converting module 300 connected to the power divider 100, and the frequency domain signal calculating module 400 connected to the frequency domain converting module 300. And the power divider 100 is configured to receive the signal to be detected sent by the signal receiving module 500 and the white noise signal sent by the white noise signal module 200, and output a first output signal (for example, the first output signal may be output from the first output interface 130) and a second output signal (for example, the second output signal may be output from the second output interface 140), where the first output signal is a signal generated by superimposing the signal to be detected and the white noise signal, and the second output signal is a signal generated by superimposing an inverted signal of the signal to be detected and the white noise signal.
Further, a white noise signal module 200 (which may be a gaussian white noise signal source, for example) is connected to the power splitter 100 for sending the white noise signal to the power splitter 100 in a manner of switching between the first white noise signal and the second white noise signal. The white noise signal module 200 can be connected to the dc power source through a switch, and then sends different white noise signals to the power divider through connection and disconnection with the dc power source.
Further, the frequency domain converting module 300 is configured to convert the received first output signal and second output signal into corresponding first frequency domain signal information and second frequency domain signal information. The spectral measurement system 10 can thus perform spectral measurements on the signal over frequency domain information.
Further, the frequency domain signal calculating module 400 is configured to perform correlation operation on the first frequency domain signal information and the second frequency domain signal information, and determine the first frequency spectrum information of the signal to be detected according to a calculation result of the correlation operation. For example, the frequency domain signal calculation module 400 may calculate the second spectrum information when the white noise signal module 200 is connected to the dc power supply and calculate the third spectrum information when the white noise signal module 200 is disconnected from the dc power supply, and then the frequency domain signal calculation module 400 may determine the first spectrum information of the signal to be detected according to the second spectrum information and the third spectrum information.
As described in the background art, components in an existing spectrum measurement system have specific frequency response characteristics, and the gain and the phase of the same component are different at different frequency points in a measured frequency band, and the gain and the phase of the different component are different at different frequency points. At the output of the spectrum measurement system, the frequency response characteristics of the multiple components are summed, resulting in a measured spectrum with the band characteristics of the multiple components superimposed. In the existing spectrum measurement technology, a Dicke switch method is generally adopted to calibrate measured spectrum information, but the Dicke switch faces the influence of gain and system noise change in the switching process.
In view of this, according to the technical solution of the embodiment of the present application, the power divider 100 is added to the spectrum measurement system, and the power divider 100 divides the signal into two paths of signals with opposite phases and equal amplitudes. Wherein the white noise signal module 200 is connected to the dc power source through the switch to transmit different white noise signals to the power divider 100. The received first and second output signals are then converted into corresponding first and second frequency-domain signal information by the frequency-domain signal conversion module 300. Then, the frequency domain signal calculation module 400 receives the first frequency domain signal information and the second frequency domain signal information, further calculates two kinds of signal spectrum information under different white noise signals, and then the frequency domain signal calculation module 400 further calculates the spectrum information of the signal to be detected according to the obtained two kinds of signal spectrum information. Therefore, the power divider 100 is added in the spectrum measurement system 10 to change the single-path measurement in the previous spectrum measurement system into the present two-path (the power divider 100 is divided into two paths of signals with opposite phases) for simultaneous measurement, then power comparison is carried out through a differential circuit (a differential circuit formed in two states of connection and disconnection of the white noise signal module 200 and a direct-connected power supply), mutual interference inside the system is eliminated by using a switch connected with the white noise signal module 200 and a direct-current power supply, the frequency band characteristics of a plurality of components superimposed on the measured spectrum due to the accumulation of the frequency response characteristics of the components in the spectrum measurement system can be eliminated, and the calibrated spectrum information is obtained. Furthermore, the technical problems that in an existing spectrum measurement system in the prior art, due to the fact that frequency response characteristic accumulation of each part can lead to the fact that frequency band characteristics of a plurality of parts are superposed in a measured spectrum, and in the process of calibrating the measured spectrum by adopting a Dicke switch, due to the fact that the Dicke switch is switched, system gain and noise can be changed are solved.
Optionally, the power divider 100 comprises: a first receiving port 110 configured to receive a signal to be detected; a second receiving port 120 configured to receive the white noise signal sent by the white noise signal module 200; a first output port 130 for outputting a first output signal; and a second output port 140 for outputting a second output signal.
Specifically, fig. 3 is an exemplary schematic diagram of the spectrum measuring system according to the present embodiment, and referring to fig. 1 and fig. 3, the power divider 100 includes a first receiving port 110 for receiving a signal to be detected. Wherein the first receiving port 110 may be, for example, the inverted distributing port shown in fig. 3, and the power divider 100 may distribute the signal to be detected received by the inverted distributing port (the first input port 110) into two paths of signals with the same amplitude and the phases of 0 ° and 180 °, respectively (compared with the signal to be detected).
Further, the power divider 100 further comprises a second receiving port 120 for receiving the white noise signal transmitted by the white noise signal module 200. Wherein the second receiving port 120 may be, for example, the in-phase distributing port shown in fig. 3, and the power distributor 100 may distribute the received white noise signal into two signals with equal amplitudes and same directions and a phase difference of 0 ° through the in-phase distributing port 120.
Further, the power divider 100 further comprises a first output port 130 for outputting a first output signal. Wherein the first output signal may be, for example, a signal generated by adding an in-phase signal (i.e., a phase of 0 ° compared to the signal to be detected) of the signal to be detected and a white noise signal.
Further, the power divider 100 further includes a second output port 140 for outputting a second output signal, where the second output signal is a signal generated by superimposing an inverted signal (i.e. compared with the signal to be detected, the phase is 180 °) of the signal to be detected and the white noise signal.
Therefore, the signal to be detected and the white noise signal are received through the first receiving port 110 and the second receiving port 120, so that double-path measurement is realized, and two paths of signals with opposite phases are distributed by the power distributor 100 through the first output port 130 and the second output port 140 to be output, so that the frequency band characteristics of a plurality of components superimposed on the measured frequency spectrum due to the accumulation of the frequency response characteristics of the components in the frequency spectrum measurement system can be eliminated by performing power comparison, and the calibrated frequency spectrum information can be obtained. Furthermore, the technical problems that in an existing spectrum measurement system in the prior art, due to the fact that frequency response characteristic accumulation of each part can lead to the fact that frequency band characteristics of a plurality of parts are superposed in a measured spectrum, and in the process of calibrating the measured spectrum by adopting a Dicke switch, due to the fact that the Dicke switch is switched, system gain and noise can be changed are solved.
Optionally, the white noise signal module 200 is connected to the dc signal source through a switch, and the white noise signal module 200 sends a first white noise signal to the power divider 100 in a state that the switch is connected; and the white noise signal module 200 sends a second white noise signal to the power divider 100 in the off state of the switch.
Specifically, referring to fig. 1 and 3, the white noise signal module 200 is connected to a direct current signal source (i.e., DC shown in fig. 3) through a switch. And the white noise signal module 200 sends the first white noise signal V to the power divider 100 in a state that the switch is connected (i.e., the white noise signal module 200 is connected to the dc power supply)CAL. Wherein the first white noise signal can be a high temperature white noise signal. When the switch is turned off (i.e., the white noise signal module 200 is not connected to the dc power supply), the white noise signal module 200 turns onThe rate allocator 100 transmits a second white noise signal VREF. Wherein the second white noise signal may be, for example, a white noise signal at ambient temperature. Therefore, the white noise signal module 200 is connected with the direct current power supply through the switch to realize the differential measurement of the frequency spectrum measurement system, and then the power comparison is carried out through the differential circuit.
Optionally, the frequency domain signal calculation module 400 includes: a digital correlation calculation unit 410 configured to calculate second spectrum information from the first frequency domain signal information and the second frequency domain signal information in a case where the power divider 100 receives the first white noise signal, and to calculate third spectrum information from the first frequency domain signal information and the second frequency domain signal information in a case where the power divider 100 receives the second white noise signal; and a spectrum information determining unit 420 configured to determine the first spectrum information of the signal to be detected according to the second spectrum information and the third spectrum information.
Specifically, referring to fig. 1 and 3, the frequency domain signal calculation module 400 includes: a digital correlation calculation unit 410 (i.e., the digital correlator shown in fig. 3), the digital correlation calculation unit 410 is configured to calculate second spectrum information (high temperature white noise signal) according to the first frequency domain signal information and the second frequency domain signal information in a case where the power divider 100 receives the first white noise signal, and calculate third spectrum information (white noise signal of ambient temperature) according to the first frequency domain signal information and the second frequency domain signal information in a case where the power divider 100 receives the second white noise signal. And a spectrum information determining unit 420 configured to determine the first spectrum information of the signal to be detected according to the second spectrum information and the third spectrum information. Therefore, accurate measurement of the frequency spectrum is realized by using power comparison through a differential measurement method.
The power is a power value at each frequency point when viewed from the frequency direction, and the whole viewed from the frequency direction is the frequency spectrum information.
Optionally, the spectrum measurement system 10 further includes: the signal receiving module 500, wherein the signal receiving module 500 is connected to the first receiving port 110 of the power divider 100, and is configured to send a signal to be detected to the power divider 100, so that the signal receiving module 500 completes acquisition of the signal to be detected.
Optionally, the frequency domain converting module 300 includes: analog/digital signal conversion units 311 to 312 configured to convert the received first analog signal information and second analog signal information into corresponding first digital signal information and second digital signal information; the polyphase filter units 321-322 are configured to select measurement frequency bands of the received first digital signal information and the second digital signal information, that is, filtering with a plurality of lower orders can be used to implement filtering with a higher original order, so as to achieve a purpose of high-precision frequency selection; and time domain/frequency domain signal conversion units 331-332 configured to convert the received first time domain signal information and second time domain signal information into corresponding first frequency domain signal information and second frequency domain signal information. The received signals are thus converted into frequency-domain signal information for calculating signal spectrum information by the analog/digital signal conversion units 311 to 312, the polyphase filter units 321 to 322, and the time/frequency-domain signal conversion units 331 to 332.
Optionally, the spectrum measurement system 10 further includes: signal amplification units 610-620 configured to amplify signal amplitudes of the first output signal and the second output signal transmitted from the power divider 100.
Specifically, referring to fig. 1 and fig. 3, the spectrum measuring system 10 further includes: the signal amplification units 610-620, the signal amplification units 610-620 are used for amplifying the signal amplitude of the first output signal and the second output signal sent from the power divider 100. The signal amplification units 610-620 are typically low noise amplifiers to preserve the original signal information to the maximum extent, i.e., amplify the received signal to a specific amplitude. Therefore, the information of the original signal is kept to the maximum extent through the signal amplifying units 610-620.
Optionally, the spectrum measurement system 10 further includes: and filtering units 710-720 configured to select signal frequency bands of the received first output signal and the second output signal.
Specifically, the spectrum measurement system 10 further includes: the filtering units 710 to 720, the filtering units 710 to 720 are used for selecting the signal frequency bands of the received first output signal and the second output signal. The filtering units 710-720 can be filters, and a user can select filters with different forms such as high pass, low pass or band pass according to requirements, so that signals outside a measured frequency band are filtered.
In addition, referring to fig. 3, the signal to be detected received by the signal receiving module 500 is denoted as VAWhen the white noise signal module 200 is connected to the dc power supply, the output high temperature white noise signal (i.e. the first white noise signal) is VCALWhen the white noise signal module 200 is disconnected from the dc power supply, the output white noise signal (i.e. the second white noise signal) at the ambient temperature is VREFNote also the attenuation g of the signal after passing through the power divider 100.
Further, in the case that the white noise signal module 200 is connected to the dc power supply, the signal output by the first output interface 130 of the power divider 100 is VA*g+VCALG and the signal output by the second output interface 140 is-VA*g+VCAL*g。
Further, it is noted that the gain of the signal amplifying unit 610 is G1 and the gain of the signal amplifying unit 620 is G2, then the signals output by the first output interface 130 and the second output interface 140 after passing through the signal amplifying units 610 to 620, the filtering units 710 to 720 and the frequency domain converting module 300 are (V)A+VCAL) G1 and (V)CAL-VA) G2, and the second spectrum information output after being processed by the digital correlation calculation unit 410 of the frequency domain calculation module 400 is:
similarly, when the white noise signal module 200 is disconnected from the dc power supply, the third spectrum information processed and output by the digital correlation calculation unit 410 is:
then, the spectrum information calculation unit 420 further calculates the second spectrum information and the third spectrum information to obtain the spectrum information of the signal to be detected, and the calculation process is as follows:
fig. 4A is frequency spectrum information of a signal to be detected; FIG. 4B is a graph of the frequency response characteristics of a plurality of components at the output of the spectral measurement system summed to result in a certain spectral shape at the output without any information input; fig. 4C is a graph that causes the measured spectrum to drift in amplitude and phase, which affects the accuracy of the measurement. And is
Similar to the measurement results shown in figure 4C,
system characteristics similar to those shown in fig. 4B; the difference between the two is the result shown in fig. 4A, which is the true spectrum information of the signal to be detected.
Therefore, according to the technical scheme of the embodiment of the application, the power divider 100 is added in the spectrum measurement system, and the signal is divided into two paths of signals with opposite phases and equal amplitudes through the power divider 100. Wherein the white noise signal module 200 is connected to the dc power source through the switch to transmit different white noise signals to the power divider 100. The received first and second output signals are then converted into corresponding first and second frequency-domain signal information by the frequency-domain signal conversion module 300. Then, the frequency domain signal calculation module 400 receives the first frequency domain signal information and the second frequency domain signal information, further calculates two kinds of signal spectrum information under different white noise signals, and then the frequency domain signal calculation module 400 further calculates the spectrum information of the signal to be detected according to the obtained two kinds of signal spectrum information. Therefore, the power divider 100 is added in the spectrum measurement system 10 to change the single-path measurement in the previous spectrum measurement system into the present two-path (the power divider 100 is divided into two paths of signals with opposite phases) for simultaneous measurement, then power comparison is carried out through a differential circuit (a differential circuit formed in two states of connection and disconnection of the white noise signal module 200 and a direct-connected power supply), mutual interference inside the system is eliminated by using a switch connected with the white noise signal module 200 and a direct-current power supply, the frequency band characteristics of a plurality of components superimposed on the measured spectrum due to the accumulation of the frequency response characteristics of the components in the spectrum measurement system can be eliminated, and the calibrated spectrum information is obtained. Furthermore, the technical problems that in an existing spectrum measurement system in the prior art, due to the fact that frequency response characteristic accumulation of each part can lead to the fact that frequency band characteristics of a plurality of parts are superposed in a measured spectrum, and in the process of calibrating the measured spectrum by adopting a Dicke switch, due to the fact that the Dicke switch is switched, system gain and noise can be changed are solved.
The relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.
Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
In the description of the present disclosure, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are presented only for the convenience of describing and simplifying the disclosure, and in the absence of a contrary indication, these directional terms are not intended to indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be taken as limiting the scope of the disclosure; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.
The above description is only for the preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (7)
1. A spectrum measurement system (10), comprising: a power divider (100), a white noise signal module (200), a frequency domain conversion module (300) connected to the power divider (100) and a frequency domain signal calculation module (400) connected to the frequency domain conversion module (300), and wherein
The power divider (100) is configured to receive a signal to be detected and a white noise signal sent by the white noise signal module (200), and output a first output signal and a second output signal, where the first output signal is a signal generated after the signal to be detected and the white noise signal are superimposed, and the second output signal is a signal generated after an inverted signal of the signal to be detected and the white noise signal are superimposed;
the white noise signal module (200) is connected with the power divider (100) and used for sending a white noise signal to the power divider (100) in a mode of switching between a first white noise signal and a second white noise signal;
the frequency domain conversion module (300) is configured to convert the received first and second output signals into corresponding first and second frequency domain signal information; and
a frequency domain signal calculation module (400) configured to perform correlation operation on the first frequency domain signal information and the second frequency domain signal information, and determine first frequency spectrum information of the signal to be detected according to a calculation result of the correlation operation, where the first frequency spectrum information is obtained by the first frequency domain signal information and the second frequency domain signal information
The frequency domain signal calculation module (400) comprises:
a digital correlation calculation unit (410) configured to calculate second spectral information from the first frequency domain signal information and the second frequency domain signal information in a case where the power divider (100) receives the first white noise signal, and to calculate third spectral information from the first frequency domain signal information and the second frequency domain signal information in a case where the power divider (100) receives the second white noise signal; and
and the spectrum information determining unit (420) is configured to determine the first spectrum information of the signal to be detected according to the second spectrum information and the third spectrum information.
2. The system of claim 1, wherein the power splitter (100) comprises:
a first receiving port (110) configured to receive a signal to be detected;
a second receiving port (120) configured to receive a white noise signal transmitted by the white noise signal module (200);
a first output port (130) for outputting the first output signal; and
a second output port (140) for outputting the second output signal.
3. The system of claim 1, wherein the white noise signal module (200) is connected to a source of direct current signal through a switch, and wherein
The white noise signal module (200) sends the first white noise signal to the power divider (100) in a state that the switch is connected; and
and the white noise signal module (200) sends the second white noise signal to the power divider (100) in the state that the switch is disconnected.
4. The system of claim 2, further comprising: a signal receiving module (500), wherein the signal receiving module (500) is connected to the first receiving port (110) of the power divider (100) for transmitting the signal to be detected to the power divider (100).
5. The system according to claim 1, wherein the frequency domain conversion module (300) comprises:
an analog/digital signal conversion unit (311-312) configured to convert the received first analog signal information and second analog signal information into corresponding first digital signal information and second digital signal information;
a polyphase filter unit (321-322) configured to select a measurement band of the received first digital signal information and the second digital signal information; and
time domain/frequency domain signal conversion units (331-332) configured to convert the received first time domain signal information and second time domain signal information into corresponding first frequency domain signal information and second frequency domain signal information.
6. The system of claim 1, further comprising: signal amplification units (610-620) configured to amplify signal amplitudes of a first output signal and a second output signal transmitted from the power divider (100).
7. The system of claim 1, further comprising: and a filtering unit (710-720) configured to select a signal frequency band of the received first output signal and the second output signal.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102147429A (en) * | 2011-02-28 | 2011-08-10 | 中国科学院国家天文台 | Broadband microwave power meter and interference signal filtering method |
| CN102749513A (en) * | 2012-06-27 | 2012-10-24 | 中国电子科技集团公司第四十一研究所 | Method of measuring intermodulation distortion frequency spectrum through vector network analyzer |
| CN104168052A (en) * | 2014-09-01 | 2014-11-26 | 北京邮电大学 | Self-interference eliminating method based on polarization information processing |
| CN104635049A (en) * | 2013-11-08 | 2015-05-20 | 苏州普源精电科技有限公司 | Spectrum analyzer with calibration function |
| CN105763494A (en) * | 2014-12-18 | 2016-07-13 | 北京科技大学 | Self-interference cancellation method and system for adaptive wireless full-duplex analog |
| CN106656322A (en) * | 2016-09-19 | 2017-05-10 | 西安电子科技大学 | Device and method for realizing instantaneous frequency measurement using phase modulator |
| CN107271769A (en) * | 2017-06-19 | 2017-10-20 | 电子科技大学 | Fundamental wave cancellation techniques passive cross modulation test system and its method of testing |
| CN107860973A (en) * | 2017-11-10 | 2018-03-30 | 中国电子科技集团公司第四十研究所 | A kind of frequency response compensation method and system applied to spectrum analyzer |
| CN108429556A (en) * | 2018-02-14 | 2018-08-21 | 妙原科技有限公司 | It is a kind of that there is device and counteracting method of the reception with interior interference in adaptive cancellation wireless transceiver system |
| CN209342804U (en) * | 2018-10-15 | 2019-09-03 | 常州星宇车灯股份有限公司 | A kind of simple signal frequency spectrum detection system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100856283B1 (en) * | 2007-04-03 | 2008-09-03 | 삼성전기주식회사 | Apparatus and Method for Eliminating Interference Noise in Mobile Communication Terminals |
| GB2518010A (en) * | 2013-09-09 | 2015-03-11 | Crfs Ltd | Frequency discriminator |
-
2019
- 2019-12-26 CN CN201911366042.6A patent/CN110988474B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102147429A (en) * | 2011-02-28 | 2011-08-10 | 中国科学院国家天文台 | Broadband microwave power meter and interference signal filtering method |
| CN102749513A (en) * | 2012-06-27 | 2012-10-24 | 中国电子科技集团公司第四十一研究所 | Method of measuring intermodulation distortion frequency spectrum through vector network analyzer |
| CN104635049A (en) * | 2013-11-08 | 2015-05-20 | 苏州普源精电科技有限公司 | Spectrum analyzer with calibration function |
| CN104168052A (en) * | 2014-09-01 | 2014-11-26 | 北京邮电大学 | Self-interference eliminating method based on polarization information processing |
| CN105763494A (en) * | 2014-12-18 | 2016-07-13 | 北京科技大学 | Self-interference cancellation method and system for adaptive wireless full-duplex analog |
| CN106656322A (en) * | 2016-09-19 | 2017-05-10 | 西安电子科技大学 | Device and method for realizing instantaneous frequency measurement using phase modulator |
| CN107271769A (en) * | 2017-06-19 | 2017-10-20 | 电子科技大学 | Fundamental wave cancellation techniques passive cross modulation test system and its method of testing |
| CN107860973A (en) * | 2017-11-10 | 2018-03-30 | 中国电子科技集团公司第四十研究所 | A kind of frequency response compensation method and system applied to spectrum analyzer |
| CN108429556A (en) * | 2018-02-14 | 2018-08-21 | 妙原科技有限公司 | It is a kind of that there is device and counteracting method of the reception with interior interference in adaptive cancellation wireless transceiver system |
| CN209342804U (en) * | 2018-10-15 | 2019-09-03 | 常州星宇车灯股份有限公司 | A kind of simple signal frequency spectrum detection system |
Non-Patent Citations (1)
| Title |
|---|
| FAST数字后端及超宽带百万通道频谱仪算法仿真;张夏 等;《天文学进展》;20160531;第249-257页 * |
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