CN112327052B - Quick high-precision frequency measurement method and system - Google Patents
Quick high-precision frequency measurement method and system Download PDFInfo
- Publication number
- CN112327052B CN112327052B CN202011203827.4A CN202011203827A CN112327052B CN 112327052 B CN112327052 B CN 112327052B CN 202011203827 A CN202011203827 A CN 202011203827A CN 112327052 B CN112327052 B CN 112327052B
- Authority
- CN
- China
- Prior art keywords
- frequency
- phase
- time
- measurement
- short
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000691 measurement method Methods 0.000 title claims abstract description 14
- 238000005259 measurement Methods 0.000 claims abstract description 50
- 238000000034 method Methods 0.000 claims abstract description 32
- 239000011159 matrix material Substances 0.000 claims abstract description 22
- 238000012545 processing Methods 0.000 claims abstract description 18
- 230000009466 transformation Effects 0.000 claims abstract description 8
- 230000008859 change Effects 0.000 claims abstract description 7
- 238000000819 phase cycle Methods 0.000 claims description 22
- 238000005070 sampling Methods 0.000 claims description 14
- 238000001514 detection method Methods 0.000 claims description 13
- 238000009499 grossing Methods 0.000 claims description 8
- 238000001228 spectrum Methods 0.000 claims description 8
- 238000012937 correction Methods 0.000 claims description 7
- 230000008569 process Effects 0.000 claims description 7
- 238000010187 selection method Methods 0.000 claims description 7
- 238000012544 monitoring process Methods 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 7
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/02—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
- G01R23/12—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage by converting frequency into phase shift
Abstract
The invention belongs to the technical field of signal processing, and relates to a rapid high-precision frequency measurement method and a rapid high-precision frequency measurement system, wherein the rapid high-precision frequency measurement method comprises the following steps of: s1, performing frequency coarse measurement on an input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal; s2, detecting the amplitude of the time-frequency matrix, extracting the maximum frequency component at each moment to form a time-frequency ridge line, and carrying out phase difference processing on the time-frequency ridge line; s3, performing phase unwrapping on the time-frequency ridge line subjected to phase difference processing by an deblurring method, and measuring the phaseSolving the true phaseThe method adopts short-time Fourier transformation and phase difference, effectively utilizes the phase information after Fourier transformation, realizes accurate measurement of frequency, and reduces the requirement of the system on computing capacity, thereby greatly reducing the manufacturing cost of the system.
Description
Technical Field
The invention relates to a rapid high-precision frequency measurement method and system, and belongs to the technical field of signal processing.
Background
With the development of communication and radar industries, the number of frequency-using devices is continuously increased, the electromagnetic environment is increasingly complex, the requirement for monitoring the electromagnetic spectrum is also continuously increased, and the capability requirement for spectrum monitoring devices is also continuously improved. The estimation of the incoming frequency is a core capability of a wideband spectrum monitoring receiver. The accuracy of the frequency estimation directly influences the characteristic identification and the function judgment of the frequency-using equipment by the frequency spectrum monitoring sensing system.
One widely used method for frequency estimation is a fourier transform method, which performs fourier transform on an incoming wave signal, and obtains a frequency peak value after fourier transform by an amplitude peak value searching method. The fourier transform can be regarded as a time-frequency analysis of the signal, and the signal frequency information can be obtained by effectively outputting the peak labels. The frequency resolution of this method is equal to the sampling rate divided by the number of fourier transform points, and the sampling rate of the system is at least required to be greater than twice the instantaneous bandwidth, subject to the nyquist sampling criterion. Therefore, when the instantaneous frequency range of the system is wider, the sampling rate of the system is also higher, and at the same time, the frequency resolution is low under the same number of Fourier transform points, and the increase of the number of Fourier transform points is required to be at the cost of increasing the calculation amount. Therefore, for the broadband coverage scenario, if a higher frequency resolution is required, the computing power of the system hardware needs to be increased, and the manufacturing cost of the system will be greatly increased.
Disclosure of Invention
Aiming at the problems, the invention aims to provide a rapid high-precision frequency measurement method and a rapid high-precision frequency measurement system, which adopt short-time Fourier transform and phase difference, effectively utilize phase information after Fourier transform, realize accurate measurement of frequency, reduce the requirement of the system on computing capacity, and greatly reduce the manufacturing cost of the system.
In order to achieve the above purpose, the present invention adopts the following technical scheme: a rapid high-precision frequency measurement method comprises the following steps: s1, performing frequency coarse measurement on an input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal; s2, detecting the amplitude of the time-frequency matrix, extracting the maximum frequency component at each moment to form a time-frequency ridge line, and carrying out phase difference processing on the time-frequency ridge line; s3, performing phase unwrapping on the time-frequency ridge line subjected to phase difference processing by an deblurring method, and measuring the phaseSolving for true phase +.>
Further, in step S1, in the course of performing frequency coarse measurement on the input signal by the short-time fourier transform, the short-time fourier transform result at the subsequent time is obtained by using the short-time fourier transform result at the previous time and the weighted value of the update data.
Further, the method for detecting the amplitude in step S2 includes the steps of: s2.1, dividing an in-phase component and a quadrature component of a complex signal obtained after short-time Fourier transformation, and calculating the arctangent of the complex signal; s2.2, obtaining a measuring phase with a value range of [0,2 pi ] according to the positive and negative of the real part and the imaginary part of the complex signal and the size of the arctangent of the complex signal; s2.3, calculating the square sum of the in-phase component and the quadrature component of the measurement phase, and obtaining the amplitude after short-time Fourier transformation.
Further, the method for extracting the maximum frequency component at each time in step S2 is as follows: detecting the amplitude of the time-frequency matrix through envelope detection, inputting the obtained amplitude of the time-frequency matrix into a pulse descriptor encoder, obtaining a frequency spectrum amplitude monitoring result at each moment, extracting the maximum value in the amplitude at each moment, and sending the maximum value to a gating interface of a multiplexer, wherein the maximum amplitude is the maximum amplitude at the current moment.
Further, the formula of the phase difference in step S2 is:
wherein f s For the sampling rate, N is the number of smoothing points,the measurement phase, i, is a sequence number indicating the measurement phase.
Further, the unwinding in step S3 is performed by giving the measured phase sequencePlus a correction phase sequence { C k (i) And (3) implementation.
Further, the phase sequence { C k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
The invention also discloses a rapid high-precision frequency measurement system, which comprises: the coarse measurement module is used for carrying out frequency coarse measurement on the input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal; the amplitude detection module is used for carrying out amplitude detection on the time frequency matrix, extracting the maximum frequency component at each moment, forming a time frequency ridge line and carrying out phase difference processing on the time frequency ridge line; an uncoiling module for carrying out phase uncoiling and overlapping on the time-frequency ridge line subjected to phase difference processing by an uncoiling fuzzy method, thereby measuring the phaseSolving for true phase +.>
Further, the formula of the phase difference method in the amplitude detection module is as follows:
wherein f s For the sampling rate, N is the number of smoothing points,the measurement phase, i, is a sequence number indicating the measurement phase.
Further, the unwind-fold in the unwind-fold module is passed to the measured phase sequencePlus a correction phase sequence { C k (i) Implementation, phase sequence { C } k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
Due to the adoption of the technical scheme, the invention has the following advantages:
1. compared with the prior art, the method provided by the invention can analyze simultaneous multi-frequency component signals, such as frequency diversity signals transmitted by the centralized radar.
2. Because the short-time Fourier transform can provide a certain processing gain, the method provided by the invention can tolerate a lower signal-to-noise ratio compared with the traditional direct phase difference method.
Drawings
FIG. 1 is a schematic diagram of a fast high-precision frequency measurement method according to an embodiment of the present invention;
fig. 2 is a time-frequency diagram of an actually input pulse signal according to an embodiment of the present invention, and fig. 2 (a) is a dual-carrier chirp signal with a frequency of 800 and a pulse width of 1369; FIG. 2 (b) is a four carrier chirp signal having a frequency 203 and a pulse width 8713
FIG. 3 is a schematic diagram of a transient frequency measurement hardware according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a phase unwrapping process in accordance with one embodiment of the present invention;
fig. 5 shows the actual perceived signal instantaneous frequency, fig. 5 (a) shows a chirp signal, fig. 5 (b) shows a two-phase encoded signal, fig. 5 (c) shows another two-phase encoded signal, fig. 5 (d) shows non-chirp, fig. 5 (e) shows one intra-pulse frequency hopping, and fig. 5 (f) shows another intra-pulse frequency hopping, according to an embodiment of the present invention.
Detailed Description
The present invention will be described in detail with reference to specific examples thereof in order to better understand the technical direction of the present invention by those skilled in the art. It should be understood, however, that the detailed description is presented only to provide a better understanding of the invention, and should not be taken to limit the invention. In the description of the present invention, it is to be understood that the terminology used is for the purpose of description only and is not to be interpreted as indicating or implying relative importance.
Example 1
The embodiment discloses a rapid high-precision frequency measurement method, as shown in fig. 1, comprising the following steps:
s1, performing frequency coarse measurement on an input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal.
In the process of carrying out frequency rough measurement on an input signal through short-time Fourier transform, the time correlation of the short-time Fourier transform is utilized, and the short-time Fourier transform result at the later moment is obtained through the weighted value of the short-time Fourier transform result and updated data at the former moment. Each value of the time-frequency matrix is obtained directly by windowed integral operation, so that the operation amount is quite large. If the window shape is taken as a cosine window, then the short-time fourier transform can be implemented using a fast iterative algorithm. A time-frequency diagram of several typical actual input pulse signals is shown in fig. 2.
S2, detecting the amplitude of the time-frequency matrix, extracting the maximum frequency component at each moment, forming a time-frequency ridge line, and carrying out phase difference processing on the time-frequency ridge line.
The method for detecting the amplitude value in the step comprises the following steps:
s2.1, dividing an in-phase component and a quadrature component of a complex signal obtained after short-time Fourier transformation, and calculating the arctangent of the complex signal;
s2.2, obtaining a measuring phase with a value range of [0,2 pi ] according to the positive and negative of the real part and the imaginary part of the complex signal and the size of the arctangent of the complex signal;
s2.3, calculating the square sum of the in-phase component and the quadrature component of the measurement phase, and obtaining the amplitude after short-time Fourier transformation.
The method for extracting the maximum frequency component at each moment in the step comprises the following steps: detecting the amplitude of the time-frequency matrix through envelope detection, inputting the obtained amplitude of the time-frequency matrix into a pulse descriptor encoder, obtaining a frequency spectrum amplitude monitoring result at each moment, extracting the maximum value in the amplitude at each moment, and sending the maximum value to a gating interface of a multiplexer, wherein the maximum amplitude is the maximum amplitude at the current moment. And forming a time-frequency ridge line from the maximum amplitude value at the current moment, and carrying out phase difference processing on the time-frequency ridge line.
Because the short-time Fourier transform does not carry out frequency spectrum shifting, the phase of the same frame is continuous, and therefore, the frequency accurate measurement can be realized by a phase difference method. Since the phase is not limited by the number of fourier transform points, finer frequency resolution can be achieved. Meanwhile, through multipoint smoothing, the performance of frequency estimation under low signal-to-noise ratio can be improved at lower hardware cost. The expression of the multipoint time-frequency ridge line phase difference is as follows:
wherein f s For the sampling rate, N is the number of smoothing points,the measuring phase, i is the sequence number representing the measuring phase, which is equivalent to realizing the tracking filtering of the signal, thereby greatly improving the detection signal-to-noise ratio of the frequency modulation signal.
As shown in fig. 3, fig. 3 is a schematic structural diagram of instantaneous frequency measurement hardware according to an embodiment of the present invention, which specifically includes the following steps: dividing the in-phase component and the quadrature component of the analytic signal to calculate the arctangent of the analytic signal; obtaining a measuring phase with a value range of [0,2 pi ] according to the positive and negative of the real part and the imaginary part; phase ambiguity resolution, solving a real phase from the measured phase; and the multiple phase difference realizes the smoothing of noise.
S3, performing phase unwrapping on the time-frequency ridge line subjected to phase difference processing by an deblurring method, and measuring the phaseSolving for true phase +.>
Fig. 4 is a schematic diagram of a phase unwrapping process, showing a single frequency complex signal measuring phase changes over two periods, with sample point A, B at the first period and C at the second period. As can be seen from fig. 3, if two sampling points are located in the same period, the measured phase and the true phase satisfy the sequential relationship, namely:
if two sampling points are located in adjacent periods, the measured phase and the real phase of the two sampling points meet the inverse relation, namely:
the phase unwrapping process is a process of moving from the solid line portion to the dotted line portion in fig. 3 so that all the sampling points satisfy the sequential relationship in phase.
In this step the unwind is performed by giving the measured phase sequencePlus a correction phase sequence { C k (i) And (3) implementation.
Phase sequence { C k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
There are two factors in practical use that can easily cause unwind errors, one is a low signal to noise ratio and the other is a high normalized carrier frequency. The invention extracts the maximum frequency component of each moment through the time-frequency matrix output by the short-time Fourier transform to form the time-frequency ridge line, and has lower unreeling error probability through carrying out phase difference and deblurring on the time-frequency ridge line. In this embodiment, the instantaneous frequency of the actual sensing signal is shown in fig. 5, where fig. 5 (a) is a chirp signal, fig. 5 (b) is a two-phase encoded signal, fig. 5 (c) is another two-phase encoded signal, fig. 5 (d) is a non-chirp signal, fig. 5 (e) is an intra-pulse frequency hopping, and fig. 5 (f) is another intra-pulse frequency hopping.
Example two
Based on the same inventive concept, the present embodiment discloses a rapid high-precision frequency measurement system, including:
the coarse measurement module is used for carrying out frequency coarse measurement on the input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal;
the amplitude detection module is used for carrying out amplitude detection on the time frequency matrix, extracting the maximum frequency component at each moment, forming a time frequency ridge line and carrying out phase difference processing on the time frequency ridge line;
an uncoiling module for carrying out phase uncoiling and overlapping on the time-frequency ridge line subjected to phase difference processing by an uncoiling fuzzy method, thereby measuring the phaseSolving for true phase +.>
The formula of the phase difference method in the amplitude detection module is as follows:
wherein f s For the sampling rate, N is the number of smoothing points,the measurement phase, i, is a sequence number indicating the measurement phase.
Unreeling in an unreeling module by giving a measured phase sequencePlus a correction phase sequence { C k (i) Implementation, phase sequence { C } k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
One way to unwind the phases is to therefore give a sequence of measured phasesPlus a correction phase sequence { C k (i) And (3) is performed. For the i-th point, correct the phase sequence { C k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) Is } is
C k (i)＝C k (i-1)
The default threshold T is-pi.
Finally, it should be noted that: the above embodiments are only for illustrating the technical aspects of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those of ordinary skill in the art that: modifications and equivalents may be made to the specific embodiments of the invention without departing from the spirit and scope of the invention, which is intended to be covered by the claims. The foregoing is merely a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes or substitutions should be covered in the protection 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. The rapid high-precision frequency measurement method is characterized by comprising the following steps of:
s1, performing frequency coarse measurement on an input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal;
in the step S1, in the process of performing frequency coarse measurement on the input signal through short-time fourier transform, the time correlation of the short-time fourier transform is utilized, and the short-time fourier transform result at the later moment is obtained through the short-time fourier transform result at the former moment and the weighted value of the updated data;
s2, detecting the amplitude of the time-frequency matrix, extracting the maximum frequency component at each moment to form a time-frequency ridge line, and carrying out phase difference processing on the time-frequency ridge line;
the formula of the phase difference in the step S2 is:
wherein f s For the sampling rate, N is the number of smoothing points,the measured phase, i is the number indicating the measured phase；
S3, performing phase unwrapping on the time-frequency ridge line subjected to phase difference processing by an deblurring method, and measuring the phaseSolving for true phase +.>
2. The rapid high-precision frequency measurement method according to claim 1, wherein the method for detecting the amplitude in the step S2 comprises the steps of:
s2.1, dividing an in-phase component and a quadrature component of a complex signal obtained after short-time Fourier transformation, and calculating the arctangent of the complex signal;
s2.2, obtaining a measuring phase with a value range of [0,2 pi ] according to the positive and negative of the real part and the imaginary part of the complex signal and the size of the arctangent of the complex signal;
s2.3, calculating the square sum of the in-phase component and the quadrature component of the measurement phase, and obtaining the amplitude after short-time Fourier transformation.
3. The rapid high-precision frequency measurement method according to claim 2, wherein the method for extracting the maximum frequency component at each moment in step S2 is as follows:
detecting the amplitude of a time-frequency matrix through envelope detection, inputting the obtained amplitude of the time-frequency matrix into a pulse descriptor encoder, obtaining a frequency spectrum amplitude monitoring result at each moment, extracting the maximum value in the amplitude at each moment, and sending the maximum value to a gating interface of a multi-path selector, wherein the maximum amplitude is the maximum amplitude at the current moment.
4. The rapid high-precision frequency measurement method according to claim 1, wherein the step S3 is performed by feeding the measurement phase sequence with the unwrapped wrapPlus a correction phase sequence { C k (i) And (3) implementation.
5. The rapid high-precision frequency measurement method according to claim 4, wherein the phase sequence { C k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
6. A rapid high-precision frequency measurement system, comprising:
the coarse measurement module is used for carrying out frequency coarse measurement on the input signal through short-time Fourier change to obtain a time-frequency matrix of the input signal;
in the coarse measurement module, in the process of performing frequency coarse measurement on an input signal through short-time Fourier transform, the time correlation of the short-time Fourier transform is utilized, and a short-time Fourier transform result at the later moment is obtained through a short-time Fourier transform result at the former moment and a weighted value of updated data;
the amplitude detection module is used for carrying out amplitude detection on the time-frequency matrix, extracting the maximum frequency component at each moment, forming a time-frequency ridge line and carrying out phase difference processing on the time-frequency ridge line;
the formula of the phase difference method in the amplitude detection module is as follows:
wherein f s For the sampling rate, N is the number of smoothing points,the measurement phase, i is a sequence number indicating the measurement phase;
an unwrapping module for unwrapping the phase of the time-frequency ridge line subjected to the phase difference processing by an unwrapping method, thereby measuring the phaseSolving for true phase +.>
7. The rapid high-precision frequency measurement system according to claim 6, wherein the unwind-fold module unwinds the measured phase sequence by feeding the measured phase sequence with the measured phase sequencePlus a correction phase sequence { C k (i) Implementation, phase sequence { C } k (i) The selection method of the } is as follows:
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)-2π
when (when)At the time { C k (i) The } is:
C k (i)＝C k (i-1)+2π
for other cases, { C k (i) The } is:
C k (i)＝C k (i-1)
wherein the threshold T used is-pi,the measurement phase, i, is a sequence number indicating the measurement phase.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011203827.4A CN112327052B (en) | 2020-11-02 | 2020-11-02 | Quick high-precision frequency measurement method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011203827.4A CN112327052B (en) | 2020-11-02 | 2020-11-02 | Quick high-precision frequency measurement method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112327052A CN112327052A (en) | 2021-02-05 |
| CN112327052B true CN112327052B (en) | 2024-02-20 |
Family
ID=74324339
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011203827.4A Active CN112327052B (en) | 2020-11-02 | 2020-11-02 | Quick high-precision frequency measurement method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112327052B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006166030A (en) * | 2004-12-07 | 2006-06-22 | Tadashi Sugiki | Color noise reduction method and color imaging apparatus |
| CN103983847A (en) * | 2014-06-12 | 2014-08-13 | 福州大学 | Self-adaptive frequency tracking measurement method based on RLS (Recursive Least Squares) in synchronized phasor measurement |
| CN107612587A (en) * | 2017-06-20 | 2018-01-19 | 西安电子科技大学 | A kind of method for parameter estimation for being used for Frequency Hopping Signal in frequency hopping non-cooperative communication |
| CN109063613A (en) * | 2018-07-20 | 2018-12-21 | 东北大学 | Based on the synchronous nonstationary random response method for extracting transformation of Generalized parametering |
| CN110048741A (en) * | 2019-04-22 | 2019-07-23 | 桂林电子科技大学 | A kind of method for parameter estimation of the Frequency Hopping Signal based on Short-Time Fractional Fourier Transform |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2093589B1 (en) * | 2008-02-22 | 2010-09-29 | Thales Nederland B.V. | A method for measuring the radial velocity of a target with a Doppler radar |
-
2020
- 2020-11-02 CN CN202011203827.4A patent/CN112327052B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006166030A (en) * | 2004-12-07 | 2006-06-22 | Tadashi Sugiki | Color noise reduction method and color imaging apparatus |
| CN103983847A (en) * | 2014-06-12 | 2014-08-13 | 福州大学 | Self-adaptive frequency tracking measurement method based on RLS (Recursive Least Squares) in synchronized phasor measurement |
| CN107612587A (en) * | 2017-06-20 | 2018-01-19 | 西安电子科技大学 | A kind of method for parameter estimation for being used for Frequency Hopping Signal in frequency hopping non-cooperative communication |
| CN109063613A (en) * | 2018-07-20 | 2018-12-21 | 东北大学 | Based on the synchronous nonstationary random response method for extracting transformation of Generalized parametering |
| CN110048741A (en) * | 2019-04-22 | 2019-07-23 | 桂林电子科技大学 | A kind of method for parameter estimation of the Frequency Hopping Signal based on Short-Time Fractional Fourier Transform |
Non-Patent Citations (1)
| Title |
|---|
| 一种基于小波脊时频分析的差分跳频信号检测方法;王明海;苟彦新;田岩;;电讯技术(03);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112327052A (en) | 2021-02-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111044971B (en) | Two-dimensional interferometer direction finding system | |
| CN101825707B (en) | Monopulse angular measurement method based on Keystone transformation and coherent integration | |
| CN109167746B (en) | Continuous wave and pulse signal quick identification device | |
| CN109387813B (en) | High-precision frequency measurement method based on broadband radar signal reception | |
| CN103983957B (en) | A kind of Doppler shift measuring method and device thereof | |
| CN110133632B (en) | Composite modulation signal identification method based on CWD time-frequency analysis | |
| CN114025379B (en) | Broadband multi-signal detection method, device and equipment | |
| CN110161472A (en) | A kind of broadband vehicle-mounted millimeter wave radar solution velocity ambiguity method based on signal multiplexing | |
| CN109975771A (en) | Wideband digital channel method based on three rank phase difference of signal | |
| CN107144811B (en) | A kind of cyclic subspace direction-finding method of single channel receiving array signal | |
| CN115494497A (en) | Phase coding pulse radar signal direction finding method | |
| CN112327052B (en) | Quick high-precision frequency measurement method and system | |
| LU101400B1 (en) | High-precision estimation method and apparatus for carrier frequency of amplitude modulation signal | |
| CN113253313A (en) | Method for improving Doppler frequency estimation precision of PMF-FFT system | |
| CN110401611B (en) | Method for rapidly detecting CPFSK signal | |
| CN114584227B (en) | Automatic burst signal detection method | |
| CN114487993B (en) | Direction finding method and system for uniform circular array correlation interferometer | |
| CN113358931B (en) | Time difference calculation method based on cross-power spectrum | |
| CN109104215A (en) | A kind of Frequency Hopping Signal chip rate blind estimating method based on wavelet transformation | |
| CN114035149A (en) | Method for improving sensitivity of interferometer direction finding system | |
| CN112968850A (en) | Weak BPSK signal carrier capturing method | |
| CN116996137B (en) | Low signal-to-noise ratio broadband linear frequency modulation signal detection method based on weighted superposition | |
| CN109387815A (en) | ApFFT composes angle-measuring method in sawtooth phase modulation linear system | |
| Cai | Fast frequency measurement algorithm based on zero crossing method | |
| CN115865230B (en) | Amplitude and phase test method and equipment, electromagnetic signal receiving and transmitting system and amplitude and phase calibration method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |