CN101909038B - Method and device for estimating blind signal bandwidth - Google Patents
Method and device for estimating blind signal bandwidth Download PDFInfo
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- CN101909038B CN101909038B CN 201010274934 CN201010274934A CN101909038B CN 101909038 B CN101909038 B CN 101909038B CN 201010274934 CN201010274934 CN 201010274934 CN 201010274934 A CN201010274934 A CN 201010274934A CN 101909038 B CN101909038 B CN 101909038B
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Abstract
The invention discloses a method and a device for estimating a blind signal bandwidth. The method comprises the following steps of: transforming a received signal according to a preset discrete Fourier transformation (DFT) point number; acquiring a mid-value bandwidth DFT point number corresponding to a bandwidth mid-value in a signal bandwidth range required by a system and calculating to obtain an initial sliding window length according to the mid-value bandwidth DFT point number; smoothing a DFT transformation result by using the initial sliding window length to obtain an estimated value of an initial bandwidth DFT point number; comparing the estimated value of the initial bandwidth DFT point number with the mid-value bandwidth DFT point number and selecting a window length factor according to a comparison result; acquiring a variable sliding window length processed by the window length factor; processing the DFT transformation result according to the variable sliding window length; and acquiring an estimated value of a signal bandwidth. In the method for estimating the blind signal bandwidth disclosed by the embodiment of the invention, the variable window length is adjusted by increasing the size of an initial estimated bandwidth of an input signal and the input signal is further smoothed, so that an estimated result is more accurate and accuracy is improved.
Description
Technical field
The present invention relates to the cognitive radio technology field, relate in particular to a kind of blind signal bandwidth method of estimation and device.
Background technology
In cognitive radio system, the usually frequency band range of given system handles, the just bandwidth of system receiver when design system.Generally, have a plurality of signals and get into simultaneously in the system receiver, the modulation system of these signals is different, and the amount of bandwidth of signal is also different.System only knows usually and received signal, and information such as the amount of bandwidth of the signal of not knowing to receive, modulation type, carrier frequency.In order better to carry out subsequent treatment such as parameter Estimation, Modulation Identification, demodulation to the received signal, estimate these signals bandwidth separately respectively after need these signals that receives simultaneously being separated usually.When prior art is carried out the signal bandwidth estimation; Usually the signal after employing will separate carries out discrete Fourier transform (DFT); And utilize predefined smoothing windows length that signal is carried out smoothly the method that a certain thresholding intercepting obtains the estimated bandwidth of signal being set then at frequency domain.
But; When utilizing the smoothing windows progress row of presetting level and smooth, if the signal bandwidth that is processed is less, the bandwidth of handling the back signal so can be by excessive broadening; And if signal bandwidth is bigger; Signal after the processing can leave more burr, estimates that therefore the bandwidth that obtains exists than mistake, and accuracy is low.
Summary of the invention
In view of this, the present invention provides a kind of blind signal bandwidth method of estimation and device, utilizes prior art to estimate that there is than mistake the problem that accuracy is low in the bandwidth that obtains with solution.Its concrete scheme is following:
A kind of blind signal bandwidth method of estimation comprises:
Count according to preset discrete Fourier transform DFT and carry out conversion receiving signal;
The corresponding intermediate value bandwidth DFT of bandwidth intermediate value that obtains in the signal bandwidth scope of system requirements counts, and counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
Utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtain the initial bandwidth DFT estimated value of counting;
Count estimated value and said intermediate value bandwidth DFT of said initial bandwidth DFT counted and compare, select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1;
It is long to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting;
According to the said DFT transformation results of said variable smoothing windows long process;
Obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
Preferably, saidly count according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long:
Confirm that the sixth that said intermediate value bandwidth DFT counts is that initial smoothing windows is long.
Preferably, the said said DFT transformation results of the long smoothing processing of said initial smoothing windows of utilizing obtains the initial bandwidth DFT estimated value process of counting and comprises:
Result after the said smoothing processing is carried out normalization;
Choose the data after the thresholding intercepting normalization, obtain the initial bandwidth DFT estimated value of counting.
Preferably, count estimated value and said intermediate value bandwidth DFT of said initial bandwidth DFT counted and compares, select the process of the long factor of window to comprise according to comparative result:
The said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value;
Whether more said multiplied result counts greater than said intermediate value bandwidth DFT, if, then choose value greater than median in the long factor span of said window, if not, then select value less than median in the long factor span of said window.
Preferably, the process of the corresponding signal bandwidth estimated value of the result after said acquisition and the said variable smoothing windows long process comprises:
The DFT that obtains after the said variable smoothing windows long process counts;
Count according to said DFT and to calculate its corresponding signal bandwidth estimated value.
A kind of blind signal bandwidth estimation unit comprises:
The DFT converter unit is used for counting according to preset discrete Fourier transform DFT and carrying out conversion receiving signal;
The initial long acquiring unit of smoothing windows, the intermediate value bandwidth DFT that is used to obtain the bandwidth intermediate value correspondence in the signal bandwidth scope of system requirements counts, and counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
The initial bandwidth DFT estimated value acquiring unit of counting is used to utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtains the initial bandwidth DFT estimated value of counting;
The long factor selected cell of window; Be used for count estimated value and said intermediate value bandwidth DFT of said initial bandwidth DFT counted and compare; Select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1;
The long acquiring unit of variable smoothing windows, it is long to be used to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting;
Variable smoothing windows long process unit is used for according to the said DFT transformation results of said variable smoothing windows long process;
Signal bandwidth estimated value acquiring unit, be used to obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
Preferably, the said initial bandwidth DFT estimated value acquiring unit of counting comprises:
The normalization unit is used for the result after the said smoothing processing is carried out normalization;
The thresholding interception unit is used to choose the data after the thresholding intercepting normalization, obtains the initial bandwidth DFT estimated value of counting.
Preferably, the long factor selected cell of said window comprises:
The unit that multiplies each other is used for the said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value;
The long factor of window is confirmed the unit; Be used for more said multiplied result and whether count, if then choose value greater than median in the long factor span of said window greater than said intermediate value bandwidth DFT; If not, then select to grow the value of median in the factor span less than said window.
Preferably, said signal bandwidth estimated value acquiring unit comprises:
The DFT acquiring unit of counting, the DFT that is used to obtain after the said variable smoothing windows long process counts;
Signal bandwidth estimated value computing unit is used for counting according to said DFT and calculates its corresponding signal bandwidth estimated value.
Can find out from above-mentioned technical scheme; The disclosed a kind of blind signal bandwidth method of estimation of the embodiment of the invention; Long through increasing the variable window of regulating according to the initial estimation amount of bandwidth of input signal; Input signal is carried out further smoothing processing, make estimated result more accurate, improved accuracy.
Description of drawings
In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below; Obviously, the accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills; Under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the flow chart of the disclosed blind signal bandwidth method of estimation of the embodiment of the invention;
Fig. 2 is the flow chart of the disclosed another blind signal bandwidth method of estimation of the embodiment of the invention;
Fig. 3 is the structural representation of the disclosed blind signal bandwidth estimation unit of the embodiment of the invention.
Embodiment
To combine the accompanying drawing in the embodiment of the invention below, the technical scheme in the embodiment of the invention is carried out clear, intactly description, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.
Increased in a kind of blind signal bandwidth method of estimation disclosed by the invention and utilized the variable window length of regulating input signal to be carried out the process of further smoothing processing according to the initial estimation amount of bandwidth of input signal; Make estimated result more accurate, improved accuracy.Its embodiment is described below:
The flow process of the disclosed a kind of blind signal bandwidth method of estimation of present embodiment is as shown in Figure 1, comprising:
Step S11, will receive signal and count according to preset discrete Fourier transform DFT and carry out conversion;
Counting of DFT conversion can be according to the principles of selected of the following stated.Usually the signal bandwidth scope of cognitive radio system demand is [B
Min, B
Max], the system estimation accuracy requirement is given as d
n, sample frequency is f
s, sample frequency f
sProcessing bandwidth by system designed is given, satisfies nyquist sampling theorem, and DFT is counted and is N, and the DFT frequency resolution does
For making the DFT frequency resolution satisfy system requirements, need make the DFT frequency resolution smaller or equal to system estimation accuracy requirement d
i≤d
n, then N can be by sample frequency fs and DFT frequency resolution d
iConfirm
Work as f
sSelect and system estimation accuracy requirement d
nGive regularly, can by
Promptly
Calculate minimum N value
When N greater than N
MinThe time, can select the size of N arbitrarily.
Step S12, the corresponding intermediate value bandwidth DFT of bandwidth intermediate value that obtains in the signal bandwidth scope of system requirements count, and count according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
Carry out in the prior art smoothing windows long choose the time, observe little bandwidth signal usually and use short window long level and smooth, big bandwidth signal uses long window length principle of smoothing.Under the condition of known signal bandwidth, find that through a large amount of emulation the length of smoothing windows is 1/4 to 1/8 o'clock of signal bandwidth DFT points N, on frequency domain, can obtain smooth effect preferably with this window length to signal smoothing.Because working as the signal of pre-treatment is Blind Source, signal bandwidth is unknown, so select the intermediate value B of system bandwidth scope for use
Mid, obtain its corresponding intermediate value bandwidth DFT and count, count according to this then and calculate the long M of initial smoothing windows
1
Step S13, utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtain the initial bandwidth DFT estimated value of counting;
According to the method for calculating estimated bandwidth in the prior art,, obtain the initial bandwidth DFT estimated value of counting in this step according to the result behind the long smoothing processing DFT of initial smoothing windows.
Step S14, count estimated value and said intermediate value bandwidth DFT of said initial bandwidth DFT counted and compare, select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1;
In this step; Count estimated value and intermediate value bandwidth DFT of initial bandwidth DFT counted and compare; And then can judge; The bandwidth of current estimated signals still less than this intermediate value, is chosen the long factor of window according to the result, so that initial bandwidth DFT is counted according to being handled by the actual conditions of estimated signal greater than bandwidth intermediate value in the signal bandwidth scope of system requirements.
Set the long M of variable window among the present invention
2By the long factor of a certain window and N
B1Multiplying each other obtains, and minimum in theory window length is 1, the long factor 1/N of its corresponding window
B1Maximal window is long to be N
B1, the long factor of corresponding window is 1, the theoretical scope of the long factor of window is (1/N
B1, 1).In the above-mentioned steps, smooth effect preferably can be obtained, so can be to choose the long factor of window in (1/8,1/4) in scope also usually in 1/4 to 1/8 o'clock of counting for signal bandwidth DFT of the length of the smoothing windows of choosing.
Step S15, to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting long;
Initial bandwidth DFT point value through after the long factor processing of window can embody the current bandwidth range characteristics that are processed signal.
Step S16, the said DFT transformation results of the said variable smoothing windows long process of foundation;
Utilize variable smoothing windows long process DFT transformation results, its smooth effect is better.
The corresponding signal bandwidth estimated value of result after step S17, acquisition and the said variable smoothing windows long process.
Signal bandwidth estimated value according to this step obtains is more accurate.
Increased in the blind signal bandwidth method of estimation disclosed by the invention and utilized the variable window length of regulating input signal to be carried out the process of further smoothing processing according to the initial estimation amount of bandwidth of input signal; Make estimated result more accurate, improved accuracy.
Another blind signal bandwidth method of estimation flow process disclosed by the invention is as shown in Figure 2, comprising:
Step S21, will receive signal and count according to preset discrete Fourier transform DFT and carry out conversion;
Step S22, the corresponding intermediate value bandwidth DFT of bandwidth intermediate value that obtains in the signal bandwidth scope of system requirements count, and count according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
Calculate B
MidShared points N in N point DFT
Mid, operational formula does
It is the number of point shared among the result of signal bandwidth intermediate value after the system handles bandwidth is carried out the DFT conversion.Because the length of smoothing windows is 1/4 to 1/8 o'clock of signal bandwidth DFT points N, on frequency domain, can obtain smooth effect preferably with this window length to signal smoothing, so choose 1/6 in the present embodiment.
Step S23, the said said DFT transformation results of the long smoothing processing of said initial smoothing windows of utilizing;
Step S24, the result after the said smoothing processing is carried out normalization;
Step S25, choose the data after the thresholding intercepting normalization, obtain the initial bandwidth DFT estimated value of counting;
Signal is after normalization, and the theoretical scope of its intercepting thresholding value is between 0 to 1, and threshold T hr and intercepting are worth relation in direct ratio.If counting, the shared DFT of signal true bandwidth is N
Br, through emulation, bandwidth intercepting value N
B1, thresholding Thr, signal true bandwidth points N
BrBut the following N of triadic relation's approximate expression
Br* (1-Thr) ≈ N
B1If it is higher that thresholding is chosen, bandwidth value is less after the intercepting, and error is bigger; If thresholding hangs down the intercepting value near actual value, but receives noise effect bigger.Thr can set according to actual conditions, and general span is between 0.4 to 0.7.
Step S26, the said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value;
Initial bandwidth DFT in this step count estimated value be one by the DFT that obtains after the long level and smooth intercepting of the fixed window intercepting value N that counts
B1, the intermediate value bandwidth DFT that this intercepting value can not be directly corresponding with the bandwidth intermediate value counts and compares, and the value that compares should be able to be reflected in the signal bandwidth of fixing initial smoothing windows after level and smooth, by N
B1* 1/ (1-Thr) obtains.Bandwidth intercepting value N in step S25
B1With thresholding Thr, signal true bandwidth points N
BrThe following N of triadic relation's approximate expression
Br* (1-Thr) ≈ N
B1, obtain a shared DFT points N of signal bandwidth after front window is long level and smooth for making the shared DFT of the initialize signal estimated value of counting
BrApproximation, so said initial bandwidth estimated value and 1 is deducted the numerical value reciprocal multiplication after the said threshold value.Its corresponding formula is N
B1* 1/ (1-Thr) is by expression formula N
Br* (1-Thr) ≈ N
B1Derivation obtains N
Br≈ N
B1* 1/ (1-Thr).
Whether step S27, more said multiplied result count greater than said intermediate value bandwidth DFT, if, execution in step S28a then, if not, execution in step S28b then;
Step S28a, choose value greater than median in the long factor span of said window;
The value of median in the factor span is grown in step S28b, selection less than said window;
Step S29, to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting long;
Respectively according to condition of different; The result of value that utilization is chosen and step S26 multiplies each other, and it is long to obtain variable smoothing windows, and is why variable; Be because its signal bandwidth according to actual estimated has been carried out corresponding adjustment; Window is long unfixing, to adapt to the needs of unlike signal bandwidth, guarantees result's accuracy.
Step S210, the said DFT transformation results of the said variable smoothing windows long process of foundation;
Utilize the long M of variable smoothing windows
2It is level and smooth that the DFT value of signal is carried out secondary, and level and smooth result is carried out normalization.Because variable smoothing windows length is according to the signal bandwidth of reality and difference, so the result after the processing also can be according to the difference of signal and difference.
DFT after step S211, the said variable smoothing windows long process of acquisition counts;
Choose Thr and the level and smooth result of normalization is carried out intercepting, obtain the corresponding DFT points N of bandwidth estimation value of signal as thresholding
B2
Step S212, count according to said DFT and to calculate its corresponding signal bandwidth estimated value.
According to the relation of the resolution of the counting of the shared DFT of bandwidth value=bandwidth * DFT, the DFT that obtains counted converts the bandwidth estimation value into, is final signal bandwidth estimated value with the product of DFT resolution.
Blind signal bandwidth method of estimation disclosed by the invention; Describe the concrete long factor of window of utilizing in detail and handle the initial bandwidth DFT estimated value process of counting; Its concrete processing procedure is according to the different situation that is processed signal and difference, and its result also more can embody the bandwidth characteristics that difference is processed signal, the result after utilize initial bandwidth DFT after handling to count the variable smoothing windows progress row secondary smoothing processing that estimated value obtains; More accurate; Estimation precision is higher, and can adapt to multiple signal bandwidth scope, has enlarged its range of application.
The embodiment of the invention does not limit the method for utilizing the corresponding DFT of bandwidth to count and calculate, relatively wait in the intermediate treatment process; Also can be according to the relation of the resolution of the counting of the shared DFT of bandwidth value=bandwidth * DFT; Be converted into bandwidth value and handle,, also need to convert bandwidth value into its corresponding DFT in the subsequent treatment and count just because the numerical value behind the DFT is discrete values; So compare with the foregoing description, operation is comparatively complicated.
Application implementation process disclosed by the invention comprises: at first according to the signal bandwidth scope [B of system requirements
Min, B
Max], the intermediate value of getting bandwidth range is designated as B
Mid, calculate B
MidShared points N among the result after the signal that receives being carried out N point DFT
Mid, operational formula does
Setting is with N
Mid1/6 long as initial smoothing windows, then the signal of handling is carried out N point DFT conversion, it is level and smooth that the data X after the conversion (n) does the long slip for M of window, X
1(k) be data after level and smooth, length is N-M+1, level and smooth back data X
1(k) divided by its maximum max (X
1(k)), obtain data X after the normalization
2(k), setting threshold value is 0.5, with X
2(k) value greater than 0.5 number as N
B1With with N
B1Corresponding bandwidth range is divided into two sections, greater than B
MidPart and less than B
MidPart; Calculate B
MidThe DFT points N
MidWith twice N
B1And N
MidRelatively, greater than N
MidThe long M of Shi Erci smoothing windows
2By N
B1With factor 1/6 multiplication generation mutually, less than N
MidThe long M of Shi Erci smoothing windows
2By N
B1With factor 1/8 multiplication generation mutually.It is long to set variable smoothing windows then, utilizes variable smoothing windows progress row smoothing processing once more, finally obtains comparatively accurate bandwidth estimation value.
The invention discloses a kind of blind signal bandwidth estimation unit; Its structure is as shown in Figure 3; Comprise: count estimated value acquiring unit 33, window of the long acquiring unit of DFT converter unit 31, initial smoothing windows 32, initial bandwidth DFT grown the long acquiring unit of factor selected cell 34, variable smoothing windows 35, variable smoothing windows long process unit 36 and signal bandwidth estimated value acquiring unit 37, wherein:
DFT converter unit 31 is used for counting according to preset discrete Fourier transform DFT and carrying out conversion receiving signal; The intermediate value bandwidth DFT that the initial long acquiring unit 32 of smoothing windows is used to obtain the bandwidth intermediate value correspondence in the signal bandwidth scope of system requirements counts, and counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long; The just initial bandwidth DFT estimated value acquiring unit 33 of counting is used to utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtains the initial bandwidth DFT estimated value of counting; The long factor selected cell 34 of window; Be used for count estimated value and said intermediate value bandwidth DFT of said initial bandwidth DFT counted and compare; Select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1; The long acquiring unit 35 of variable smoothing windows, the variable smoothing windows that is used to obtain the initial bandwidth estimated value correspondence after said window is grown factor processing is long; Variable smoothing windows long process unit 36 is used for according to the said DFT transformation results of said variable smoothing windows long process; Signal bandwidth estimated value acquiring unit 37 be used to obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
The initial bandwidth DFT estimated value acquiring unit 33 of counting comprises: normalization unit 331 is used for the result after the said smoothing processing is carried out normalization; Thresholding interception unit 332 is used to choose the data after the thresholding intercepting normalization, obtains the initial bandwidth DFT estimated value of counting.
The long factor selected cell 34 of window comprises: the unit 341 that multiplies each other is used for the said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value; The long factor of window confirms that unit 342 is used for more said multiplied result and whether counts greater than said intermediate value bandwidth DFT; If; Then choose value, if not, then select value less than median in the long factor span of said window greater than median in the long factor span of said window.
The process of each unit execution concrete operations is described below in this device:
The signal that DFT converter unit 31 receives system is counted according to preset discrete Fourier transform DFT and is carried out conversion; The signal that obtains dispersing; The initial long acquiring unit 32 of smoothing windows obtains intermediate value bandwidth DFT according to the bandwidth intermediate value in the signal bandwidth scope of system requirements and counts; And count according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long; Usually choose that intermediate value bandwidth DFT counts 1/8th to 1/4th, the initial bandwidth DFT estimated value acquiring unit 33 of counting utilizes the discrete signal after the said DFT conversion of the long smoothing processing of said initial smoothing windows, obtains the initial bandwidth DFT estimated value of counting; The long factor selected cell 34 of window is counted count estimated value and intermediate value bandwidth DFT of initial bandwidth DFT to compare; Select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1; And utilize the long factor of the window that obtains to handle initial bandwidth DFT and count, it is long that the long acquiring unit 35 of variable smoothing windows obtains its corresponding variable smoothing windows according to the initial bandwidth estimated value after handling through the long factor of said window; Variable smoothing windows long process unit 36 is according to the said DFT transformation results of variable smoothing windows long process, and is last, signal bandwidth estimated value acquiring unit 37 obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
Each embodiment adopts the mode of going forward one by one to describe in this specification, and what each embodiment stressed all is and the difference of other embodiment that identical similar part is mutually referring to getting final product between each embodiment.For the disclosed device of embodiment, because it is corresponding with the embodiment disclosed method, so description is fairly simple, relevant part is partly explained referring to method and is got final product.
The professional can also further recognize; The unit and the algorithm steps of each example of describing in conjunction with embodiment disclosed herein; Can realize with electronic hardware, computer software or the combination of the two; For the interchangeability of hardware and software clearly is described, the composition and the step of each example described prevailingly according to function in above-mentioned explanation.These functions still are that software mode is carried out with hardware actually, depend on the application-specific and the design constraint of technical scheme.The professional and technical personnel can use distinct methods to realize described function to each certain applications, but this realization should not thought and exceeds scope of the present invention.
The method of describing in conjunction with embodiment disclosed herein or the step of algorithm can be directly with the software modules of hardware, processor execution, and perhaps the combination of the two is implemented.Software module can place the storage medium of any other form known in random asccess memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or the technical field.
To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the present invention.Multiple modification to these embodiment will be conspicuous concerning those skilled in the art, and defined General Principle can realize under the situation that does not break away from the spirit or scope of the present invention in other embodiments among this paper.Therefore, the present invention will can not be restricted to these embodiment shown in this paper, but will meet and principle disclosed herein and features of novelty the wideest corresponding to scope.
Claims (9)
1. a blind signal bandwidth method of estimation is characterized in that, comprising:
Carry out the transformation of variables of N point DFT point with receiving signal according to preset discrete Fourier transform;
The corresponding intermediate value bandwidth DFT of bandwidth intermediate value that obtains in the signal bandwidth scope of system requirements counts, and counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
Utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtain the initial bandwidth DFT estimated value of counting;
The said initial bandwidth DFT estimated value of counting is calculated the back and counted and compare with said intermediate value bandwidth DFT, select the long factor of window according to comparative result, the span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1;
It is long to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting;
According to the said DFT transformation results of said variable smoothing windows long process;
Obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
2. method according to claim 1 is characterized in that, saidly counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long:
Confirm that the sixth that said intermediate value bandwidth DFT counts is that initial smoothing windows is long.
3. method according to claim 2 is characterized in that, the said said DFT transformation results of the long smoothing processing of said initial smoothing windows of utilizing obtains the initial bandwidth DFT estimated value process of counting and comprises:
Result after the said smoothing processing is carried out normalization;
Choose the data after the thresholding intercepting normalization, obtain the initial bandwidth DFT estimated value of counting.
4. method according to claim 3 is characterized in that, the said initial bandwidth DFT estimated value of counting is calculated the back and counted and compare with said intermediate value bandwidth DFT, selects the process of the long factor of window to comprise according to comparative result:
The said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value, and wherein, intercepting threshold value scope is between 0 to 1;
Whether more said multiplied result counts greater than said intermediate value bandwidth DFT, if, then choose value greater than median in the long factor span of said window, if not, then select value less than median in the long factor span of said window.
5. according to any described method among the claim 1-4, it is characterized in that the process of the signal bandwidth estimated value that the result after said acquisition and the said variable smoothing windows long process is corresponding comprises:
The DFT that obtains after the said variable smoothing windows long process counts;
Count according to said DFT and to calculate its corresponding signal bandwidth estimated value.
6. a blind signal bandwidth estimation unit is characterized in that, comprising:
The DFT converter unit is used for carrying out the transformation of variables of N point DFT point with receiving signal according to preset discrete Fourier transform;
The initial long acquiring unit of smoothing windows, the intermediate value bandwidth DFT that is used to obtain the bandwidth intermediate value correspondence in the signal bandwidth scope of system requirements counts, and counts according to said intermediate value bandwidth DFT that to calculate initial smoothing windows long;
The initial bandwidth DFT estimated value acquiring unit of counting is used to utilize the said DFT transformation results of the long smoothing processing of said initial smoothing windows, obtains the initial bandwidth DFT estimated value of counting;
The long factor selected cell of window; Be used for the said initial bandwidth DFT estimated value of counting is calculated the back and counted and compare with said intermediate value bandwidth DFT; Select the long factor of window according to comparative result; The span of the long factor of said window is for the inverse of the estimated value of counting greater than said initial bandwidth DFT, less than 1;
The long acquiring unit of variable smoothing windows, it is long to be used to obtain initial bandwidth DFT after the long factor of said window the is handled corresponding variable smoothing windows of estimated value of counting;
Variable smoothing windows long process unit is used for according to the said DFT transformation results of said variable smoothing windows long process;
Signal bandwidth estimated value acquiring unit, be used to obtain with said variable smoothing windows long process after the corresponding signal bandwidth estimated value of result.
7. device according to claim 6 is characterized in that, the said initial bandwidth DFT estimated value acquiring unit of counting comprises:
The normalization unit is used for the result after the said smoothing processing is carried out normalization;
The thresholding interception unit is used to choose the data after the thresholding intercepting normalization, obtains the initial bandwidth DFT estimated value of counting.
8. device according to claim 7 is characterized in that, the long factor selected cell of said window comprises:
The unit that multiplies each other is used for the said initial bandwidth DFT estimated value and 1 of counting is deducted the numerical value reciprocal multiplication after the said threshold value, and wherein, intercepting threshold value scope is between 0 to 1;
The long factor of window is confirmed the unit; Be used for more said multiplied result and whether count, if then choose value greater than median in the long factor span of said window greater than said intermediate value bandwidth DFT; If not, then select to grow the value of median in the factor span less than said window.
9. according to any described device among the claim 6-8, it is characterized in that said signal bandwidth estimated value acquiring unit comprises:
The DFT acquiring unit of counting, the DFT that is used to obtain after the said variable smoothing windows long process counts; Signal bandwidth estimated value computing unit is used for counting according to said DFT and calculates its corresponding signal bandwidth estimated value.
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| CN105916179B (en) * | 2016-05-30 | 2019-07-26 | 北京邮电大学 | A kind of band width estimation method and device |
| CN109507495B (en) * | 2018-10-17 | 2020-12-15 | 华北水利水电大学 | Variable-window-length quasi-synchronization grid-connected parameter measurement method |
| CN112214895A (en) * | 2020-10-14 | 2021-01-12 | 中国船舶重工集团公司第七二四研究所 | Fourier multi-beam forming method with transform point number optimization design |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101485117A (en) * | 2006-07-05 | 2009-07-15 | 皇家飞利浦电子股份有限公司 | Bandwidth asymmetric communication system |
| CN101507219A (en) * | 2006-08-18 | 2009-08-12 | Nxp股份有限公司 | Time error estimation for data symbols |
| CN101682588A (en) * | 2007-03-27 | 2010-03-24 | 摩托罗拉公司 | Channel estimator for OFDM systems |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4701964B2 (en) * | 2005-09-27 | 2011-06-15 | 日本電気株式会社 | Multi-user receiver |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101485117A (en) * | 2006-07-05 | 2009-07-15 | 皇家飞利浦电子股份有限公司 | Bandwidth asymmetric communication system |
| CN101507219A (en) * | 2006-08-18 | 2009-08-12 | Nxp股份有限公司 | Time error estimation for data symbols |
| CN101682588A (en) * | 2007-03-27 | 2010-03-24 | 摩托罗拉公司 | Channel estimator for OFDM systems |
Non-Patent Citations (1)
| Title |
|---|
| 葛启宏等.《基于二维DFT 的多导频模式OFDM信道估计算法》.《清华大学学报(自然科学版)》.2004,第44卷(第6期), * |
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