CN109450837A - A kind of estimation of sampling frequency offset and compensation method and system - Google Patents
A kind of estimation of sampling frequency offset and compensation method and system Download PDFInfo
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- CN109450837A CN109450837A CN201811452250.3A CN201811452250A CN109450837A CN 109450837 A CN109450837 A CN 109450837A CN 201811452250 A CN201811452250 A CN 201811452250A CN 109450837 A CN109450837 A CN 109450837A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
- H04L27/14—Demodulator circuits; Receiver circuits
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/0014—Carrier regulation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/0014—Carrier regulation
- H04L2027/0024—Carrier regulation at the receiver end
- H04L2027/0026—Correction of carrier offset
Abstract
This application provides a kind of method and system of sampling frequency offset estimation and compensation, this method comprises: determining the windowing position of current sign, obtain the sampled point of current sign from data buffer storage according to windowing position；After the value of the sampled point of current sign is taken absolute value, five equally spaced sampled values in each symbol period are calculated；Utilize five the first judgement expression formulas of equal interval sampling value iterative calculation and the second judgement expression formula；When needing to carry out sampling frequency offset compensation according to the first judgement expression formula is determining, determine that windowing adjusting parameter is adjusted with split window position using the second judgement expression formula.This method can be only with a small amount of addition and subtraction and comparison operation, it can be achieved with the sampling frequency offset estimation and compensation of GFSK system, overcome the problem of causing sign synchronization position gradually to deviate error because of sampling frequency offset effect in receiver, and, reliablely and stablely sampling frequency offset estimation and compensation can be realized under the conditions of down to the signal-to-noise ratio of 2dB, especially suitable for highly sensitive GFSK system.
Description
Technical field
This application involves field of communication technology more particularly to the method and system of a kind of sampling frequency offset estimation and compensation.
Background technique
GFSK (Gauss Frequency Shift Keying, GFSK Gaussian Frequency Shift Keying) modulation because have permanent width envelope,
The advantages that power spectrum is concentrated and frequency spectrum is relatively narrow, has been widely used in bluetooth, Bluetooth Low Energy and various 2.4G at present
In proprietary protocol wireless communication system.
However, the transmitter due to wireless communication system usually provides work clock by different crystal oscillators from receiver,
Frequency without same crystal oscillator can have certain deviation, and sampling frequency offset effect can gradually accumulate, may only meeting for receiving and dispatching short frame
Receptivity is caused to deteriorate to a certain degree, and frame long for transmitting-receiving then may cause and be unable to properly receive completely.Such as: assuming that hair
It penetrates machine and receiver is all made of the crystal oscillator that precision is 50ppm, then when the two bias direction is opposite, then receiver and transmitter
Clock frequency maximum deviation is 100ppm, i.e., due to the presence of sampling frequency deviation, every 10,000 data sampled points can deviate 1
Sampled point, and every 100,000 data sampled points then can 10 sampled points of cumulative offset.In receivers, even if it is real when frame starts
Show complete ideal sign synchronization, but due to the influence of sampling frequency deviation, it is accumulative with data sampling point offset number,
Originally accurately sign synchronization position will gradually deviate error.
Therefore, how to overcome in receiver because sampling frequency offset effect causes sign synchronization position gradually to deviate error, be this
The problem of field technical staff's urgent need to resolve.
Summary of the invention
In view of this, overcoming receiver this application provides a kind of method and system of sampling frequency offset estimation and compensation
Middle the problem of causing sign synchronization position gradually to deviate error because of sampling frequency offset effect.
To achieve the above object, this application provides following technical schemes:
A kind of estimation of sampling frequency offset and compensation method, this method comprises:
The windowing position for determining current sign obtains the sampling of current sign according to the windowing position from data buffer storage
Point；
After the value of the sampled point of the current sign is taken absolute value, calculates in each symbol period five and equally spaced adopt
Sample value；
Utilize the first judgement expression formula of five equal interval sampling values iterative calculation and the second judgement expression formula；
When needing to carry out sampling frequency offset compensation according to the first judgement expression formula is determining, second decisional table is utilized
Determine that windowing adjusting parameter is adjusted with split window position up to formula.
Preferably, the windowing position of the determining current sign includes:
When the current sign is initial symbol, using predeterminated position as the windowing position of the current sign；
When the current sign is not initial symbol, determined according to the windowing position of a upper symbol and windowing adjusting parameter
The windowing position of the current sign.
Preferably, the first judgement expression formula are as follows: E (j)=E (j-1)+S_2 (j)-(S_0 (j)+S_4 (j))/2,
Middle E (- 1) is 0；
The second judgement expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0；
Wherein, j indicates GFSK symbol counter value, and the counting period of GFSK symbol counter is N, i.e., j value is 0 to N-1；
S_0 (j), S_1 (j), S_2 (j), S_3 (j), S_4 (j) indicate five equal interval sampling values of j-th of GFSK symbol, S_0 (j)
For the sampled value of initial position in GFSK symbol period, S_1 (j) is the sampled value of 1/4 position in GFSK symbol period, S_2 (j)
For the sampled value of 1/2 position in GFSK symbol period, S_3 (j) is the sampled value of 3/4 position in GFSK symbol period, S_4 (j)
For the sampled value of end position in GFSK symbol period.
Preferably, the first judgement expression formula determines that needing to carry out frequency deviation compensation includes:
When GFSK symbol counter value j is N-1, sampling frequency offset is judged whether there is using the first judgement expression formula
Caused offset；
When the value of the first judgement expression formula is less than or equal to preset threshold value, it is determined that need to carry out sampling frequency offset benefit
It repays.
Preferably, described to determine that windowing adjusting parameter includes: using the second judgement expression formula
Judge whether the value of second predicated expressions is greater than or equal to 0；
When the value of second predicated expressions is greater than or equal to 0, then the windowing adjusting parameter designated symbol is synchronous
+ M sampled points of position adjustment；When the value of second predicated expressions is less than 0, then the windowing adjusting parameter designated symbol
- M sampled points of sync bit adjustment；The M is positive integer.
A kind of estimation of sampling frequency offset and compensation system, the system include:
Symbol windowing unit, for determining the windowing position of current sign, according to the windowing position from data buffer storage
Obtain the sampled point of current sign；
Sampled value computing unit calculates each symbol after the value of the sampled point of the current sign takes absolute value
Five equally spaced sampled values in period；
Unit is iterated to calculate, for utilizing five equal interval sampling values iterative calculation the first judgement expression formula and second
Adjudicate expression formula；
Decision unit, for determining the need for carrying out sampling frequency offset compensation according to the first judgement expression formula；
Adjusting parameter determination unit, for needing to carry out sampling frequency offset compensation when according to the first judgement expression formula determination
When, determine that windowing adjusting parameter is adjusted with split window position using the second judgement expression formula.
Preferably, the symbol windowing unit includes:
First son windowing unit, is used for when the current sign is initial symbol, using predeterminated position as described current
The windowing position of symbol；
Second son windowing unit, for when the current sign is not initial symbol, according to the windowing position of a upper symbol
Adjusting parameter of setting and open a window determines the windowing position of the current sign；
Sampled point acquiring unit, for what is determined according to the first son windowing unit or the second son windowing unit
Windowing position obtains the sampled point of current sign from data buffer storage.
Preferably, the first judgement expression formula are as follows: E (j)=E (j-1)+S_2 (j)-(S_0 (j)+S_4 (j))/2,
Middle E (- 1) is 0；
The second judgement expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0；
Wherein, j indicates GFSK symbol counter value, and the counting period of GFSK symbol counter is N, i.e., j value is 0 to N-1；
S_0 (j), S_1 (j), S_2 (j), S_3 (j), S_4 (j) indicate five equal interval sampling values of j-th of GFSK symbol, S_0 (j)
For the sampled value of initial position in GFSK symbol period, S_1 (j) is the sampled value of 1/4 position in GFSK symbol period, S_2 (j)
For the sampled value of 1/2 position in GFSK symbol period, S_3 (j) is the sampled value of 3/4 position in GFSK symbol period, S_4 (j)
For the sampled value of end position in GFSK symbol period.
Preferably, the decision unit includes:
First judging unit, for being sentenced using the first judgement expression formula when GFSK symbol counter value j is N-1
It is disconnected to be deviated with the presence or absence of caused by sampling frequency offset；
First determination unit, for when the value of the first judgement expression formula is less than or equal to preset threshold value, it is determined that need
Sampling frequency offset compensation is carried out, otherwise, is compensated without sampling frequency offset.
Preferably, the adjusting parameter determination unit includes:
Second judgment unit, for judging whether the value of second predicated expressions is greater than or equal to 0；
Second determination unit, for when the value of second predicated expressions is greater than or equal to 0, then the windowing to adjust
+ M sampled points of parameter indicator sync bit adjustment；When the value of second predicated expressions is less than 0, then the windowing
- M sampled points of adjusting parameter designated symbol sync bit adjustment；The M is positive integer.
From the above technical scheme, this application provides a kind of estimation of sampling frequency offset and compensation methodes, and main includes symbol
Number windowing, calculate five equal interval sampling values, calculate two judgement expression formulas and judgement with generate symbol windowing adjusting parameter
Four committed steps.The offset estimation provided by the present application and compensation method can be only with a small amount of addition and subtraction and comparison operation, energy
The sampling frequency offset estimation and compensation for realizing GFSK system, overcome in receiver because sampling frequency offset effect leads to sign synchronization position
Gradually the problem of offset error, also, the program can realize reliablely and stablely sampling frequency offset under the conditions of down to the signal-to-noise ratio of 2dB
Estimation and compensation, especially suitable for highly sensitive GFSK system.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
The embodiment of invention for those of ordinary skill in the art without creative efforts, can also basis
The attached drawing of offer obtains other attached drawings.
Fig. 1 is the flow chart of a kind of sampling frequency offset estimation and compensation method that the embodiment of the present application one provides；
Fig. 2 is a kind of sampling frequency offset estimation provided by the present application and compensation method realization step block diagram；
Fig. 3 is a kind of equally spaced sampled value schematic diagram calculation provided by the present application；
Fig. 4 is the structural schematic diagram of a kind of sampling frequency offset estimation and compensation system that the embodiment of the present application three provides；
Fig. 5 is a kind of structural schematic diagram for symbol windowing unit that the embodiment of the present application four provides.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
To overcome the problems, such as in receiver because sampling frequency offset effect causes sign synchronization position gradually to deviate error, the application
The method and system of a kind of sampling frequency offset estimation and compensation are provided, concrete scheme is as described below:
Embodiment one
The embodiment of the present application one provides a kind of estimation of sampling frequency offset and compensation method, and this method is applied to GFSK modulation system
In system, as shown in Figure 1, this method comprises:
S101: determining the windowing position of current sign, and adopting for current sign is obtained from data buffer storage according to windowing position
Sampling point；
Specifically, determining that the windowing position of current sign includes:
When current sign is initial symbol, using predeterminated position as the windowing position of current sign；
When current sign is not initial symbol, determined according to the windowing position of a upper symbol and windowing adjusting parameter current
The windowing position of symbol.
As shown in connection with fig. 2, Fig. 2 is a kind of sampling frequency offset estimation provided by the present application and compensation method realization step block diagram.
40 continuous sampling point datas of storage coexist in data buffer storage, and the GFSK symbol in the present embodiment in receiver after phase difference demodulation is
8 times of over-samplings, i.e. a GFSK symbol include the sampled point in 8 data buffer storages.Current windowing position is determined, according to currently opening
Window position obtains the data sampling point of current GFSK symbol from data buffer storage.Ideal symbol windowing position is system when initial
In other synchronization modules determine, as predeterminated position, specially D16 to D23, i.e., 8 samplings of i-th windowing GFSK symbol
Point is X_0 (i)=D16, X_1 (i)=D17, X_2 (i)=D18, and so on.When the position that opens a window adjusts+2 sampled points,
One windowing GFSK symbol 8 sampled points be X_0 (i)=D (16+2), X_1 (i)=D (17+2), X_2 (i)=D (18+2),
The rest may be inferred.When the position that opens a window adjusts -2 sampled points, 8 sampled points of a windowing GFSK symbol are X_0 (i)=D
(16-2), X_1 (i)=D (17-2), X_2 (i)=D (18-2), and so on.Since 40 companies of storage coexist in data cache module
Continuous sample point data, which means the embodiment at most, can add up symbol windowing position adjusting 16 sampled points forward or backward.
S102: after the value of the sampled point of current sign is taken absolute value, calculate in each symbol period five it is equally spaced
Sampled value；
Since the value of the sampled point of current sign is possible to as negative value, therefore, it is necessary to first by the sampled point of current sign
Value takes absolute value, then calculates five equally spaced sampled values in each symbol period.
Specifically, calculating five equally spaced sampled values in each symbol period using abs function in this application.
S103: five the first judgement expression formulas of equal interval sampling value iterative calculation and the second judgement expression formula are utilized；
S104: when needing to carry out sampling frequency offset compensation according to the first judgement expression formula is determining, the second judgement is utilized to express
Formula determines that windowing adjusting parameter is adjusted with split window position.
From the above technical scheme, the sampling frequency offset estimation and compensation method that the embodiment of the present application one provides, can be only
With a small amount of addition and subtraction and comparison operation, can be achieved with the sampling frequency offset estimation and compensation of GFSK system, overcome in receiver because
The problem of sampling frequency offset effect causes sign synchronization position gradually to deviate error, also, the program can be in the signal-to-noise ratio down to 2dB
Under the conditions of realize reliablely and stablely sampling frequency offset estimation and compensation, especially suitable for highly sensitive GFSK system.
Embodiment two
On the basis of example 1, the embodiment of the present application two provides a kind of more specific sampling frequency offset estimation and compensation
Method, main body step still can be found in shown in Fig. 1 and Fig. 2, this method comprises:
S101: determining the windowing position of current sign, and adopting for current sign is obtained from data buffer storage according to windowing position
Sampling point；
Specifically, determining that the windowing position of current sign includes:
When current sign is initial symbol, using predeterminated position as the windowing position of current sign；
When current sign is not initial symbol, determined according to the windowing position of a upper symbol and windowing adjusting parameter current
The windowing position of symbol.
As shown in connection with fig. 2, Fig. 2 is a kind of sampling frequency offset estimation provided by the present application and compensation method realization step block diagram.
40 continuous sampling point datas of storage coexist in data buffer storage, and the GFSK symbol in the present embodiment in receiver after phase difference demodulation is
8 times of over-samplings, i.e. a GFSK symbol include the sampled point in 8 data buffer storages.Current windowing position is determined, according to currently opening
Window position obtains the data sampling point of current GFSK symbol from data buffer storage.Ideal symbol windowing position is system when initial
In other synchronization modules determine, as predeterminated position, specially D16 to D23, i.e., 8 samplings of i-th windowing GFSK symbol
Point is X_0 (i)=D16, X_1 (i)=D17, X_2 (i)=D18, and so on.When the position that opens a window adjusts+2 sampled points,
One windowing GFSK symbol 8 sampled points be X_0 (i)=D (16+2), X_1 (i)=D (17+2), X_2 (i)=D (18+2),
The rest may be inferred.When the position that opens a window adjusts -2 sampled points, 8 sampled points of a windowing GFSK symbol are X_0 (i)=D
(16-2), X_1 (i)=D (17-2), X_2 (i)=D (18-2), and so on.Since 40 companies of storage coexist in data cache module
Continuous sample point data, which means the embodiment at most, can add up symbol windowing position adjusting 16 sampled points forward or backward.
S102: after the value of the sampled point of current sign is taken absolute value, calculate in each symbol period five it is equally spaced
Sampled value；
Since the value of the sampled point of current sign is possible to as negative value, therefore, it is necessary to first by the sampled point of current sign
Value takes absolute value, then calculates five equally spaced sampled values in each symbol period.
The sampling point value for the GFSK symbol that step S101 opens a window is taken absolute value first, then calculates each GFSK symbol
The sampled value of initial position, 1/4 position, 1/2 position, 3/4 position and end position totally five positions at equal intervals in number period,
The sampled value of i-th of GFSK symbol is indicated with S_0 (i), S_1 (i), S_2 (i), S_3 (i), S_4 (i) respectively.
Specifically, calculating five equally spaced sampled values in each symbol period using abs function in this application.Tool
Body schematic diagram calculation can be found in shown in Fig. 3, wherein S_0 (i) ≈ abs (X_0 (i)), S_1 (i)=(abs (X_1 (i))+abs
(X_2 (i)))/2, S_2 (i)=(abs (X_3 (i))+abs (X_4 (i)))/2, S_3 (i)=(abs (X_5 (i))+abs (X_6
(i)))/2, S_4 (i) ≈ abs (X_7 (i)).
S103: five the first judgement expression formulas of equal interval sampling value iterative calculation and the second judgement expression formula are utilized；
Judgement expression formula E (j) and F (j) are calculated, GFSK symbol counter value is indicated with j, the counting period is N, i.e. j value takes 0
To N-1, wherein N is a system design parameters, and specific determine can be emulated according to different application.
Iterative calculation the first judgement expression formula are as follows: E (j)=E (j-1)+S_2 (j)-(S_0 (j)+S_4 (j))/2, wherein E
It (- 1) is 0；
Further, the second judgement of iterative calculation expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1)
It is 0.
S104: when needing to carry out sampling frequency offset compensation according to the first judgement expression formula is determining, the second judgement is utilized to express
Formula determines that windowing adjusting parameter is adjusted with split window position.
When GFSK symbol counter value j is N-1, it is made to determine whether there are offset caused by sampling frequency offset, if the
When one judgement expression formula E (N-1) value is greater than pre-set threshold value STR_TH, then it represents that sampling location caused by sampling frequency offset is inclined
Shifting is smaller, and without carrying out sample offset compensation deals, i.e. the holding symbol windowing constant windowing adjusting parameter in position is 0.When first
When adjudicating expression formula E (N-1) value less than or equal to pre-set threshold value STR_TH, then it represents that need further progress sampling frequency offset
Compensation deals realize that sampling frequency offset is compensated by adjusting sign synchronization position forward or backward, and primary adjustment can be M sampling
Point.When the first judgement expression formula E (N-1) value is less than or equal to pre-set threshold value STR_TH, further relatively second sentences
Whether the value for determining expression formula F (N-1) is greater than or equal to 0, when F (N-1) is greater than or equal to 0, then symbol sync bit adjustment+M
A sampled point, conversely, when F (N-1) is less than 0 ,-M sampled points of then symbol sync bit adjustment.Wherein, M is positive integer, is led to
1 or 2 is often taken, i.e., once adjusts 1 or 2 sampled point forward or backward, naturally it is also possible to choose other values, in this application
It does not limit.
For example, taking 2048 when counting period N, i.e. j value is 0 to 2047, the first judgement of iterative calculation expression formula E (j)=E
(j-1)+S_2 (j)-(S_0 (j)+S_4 (j))/2, wherein E (- 1) is 0.Further the second judgement expression formula F (j) of iterative calculation
=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0.
When GFSK symbol counter value j is 2047, it is made to determine whether there are offset caused by sampling frequency offset, if the
When one judgement expression formula E (2047) value is greater than pre-set threshold value STR_TH=150, then it represents that sampling caused by sampling frequency offset
Positional shift is smaller, and without carrying out sample offset compensation deals, i.e. the holding symbol windowing constant windowing adjusting parameter in position is 0.
When the first judgement expression formula E (2047) value is less than or equal to pre-set threshold value STR_TH, then it represents that need further progress
Sampling frequency offset compensation deals.
When the first judgement expression formula E (2047) value is less than or equal to pre-set threshold value STR_TH, further relatively
Whether the value of the second predicated expressions F (2047) is greater than or equal to 0, the then symbol sync bit when F (2047) are greater than or equal to 0
+ 2 sampled points are adjusted, conversely, then symbol sync bit adjusts -2 sampled points when F (2047) is less than 0.
It should be noted that above-mentioned be merely illustrative, specific parameters value can pass through according to specific application
Other values are chosen in emulation, and it is only one of the embodiment compared with the figure of merit that N, which takes 2048,.
From the above technical scheme, the sampling frequency offset estimation and compensation method that the embodiment of the present application two provides, can be only
With a small amount of addition and subtraction and comparison operation, can be achieved with the sampling frequency offset estimation and compensation of GFSK system, overcome in receiver because
The problem of sampling frequency offset effect causes sign synchronization position gradually to deviate error, also, the program can be in the signal-to-noise ratio down to 2dB
Under the conditions of realize reliablely and stablely sampling frequency offset estimation and compensation, especially suitable for highly sensitive GFSK system.
Embodiment three
On the basis of example 1, and realize that method described in embodiment, the embodiment of the present application three provide one kind and adopt
Sample offset estimation and compensation system, as shown in figure 4, Fig. 4 is a kind of estimation of sampling frequency offset and mend that the embodiment of the present application three provides
The structural schematic diagram of system is repaid, which includes: symbol windowing unit 101, sampled value computing unit 102, iterative calculation unit
103, decision unit 104 and adjusting parameter determination unit 105, wherein
Symbol windowing unit 101 is obtained from data buffer storage for determining the windowing position of current sign according to windowing position
Take the sampled point of current sign；
Sampled value computing unit 102 calculates each symbol week after the value of the sampled point of current sign takes absolute value
Five equally spaced sampled values in phase；
Unit 103 is iterated to calculate, for utilizing five equal interval sampling value iterative calculation the first judgement expression formulas and second
Adjudicate expression formula；
Decision unit 104, for determining the need for carrying out sampling frequency offset compensation according to the first judgement expression formula；
Adjusting parameter determination unit 105, for needing to carry out sampling frequency offset compensation when according to the first judgement expression formula determination
When, determine that windowing adjusting parameter is adjusted with split window position using the second judgement expression formula.
From the above technical scheme, the sampling frequency offset estimation and compensation system that the embodiment of the present application one provides, can be only
With a small amount of addition and subtraction and comparison operation, can be achieved with the sampling frequency offset estimation and compensation of GFSK system, overcome in receiver because
The problem of sampling frequency offset effect causes sign synchronization position gradually to deviate error, also, the program can be in the signal-to-noise ratio down to 2dB
Under the conditions of realize reliablely and stablely sampling frequency offset estimation and compensation, especially suitable for highly sensitive GFSK system.
Example IV
On the basis of embodiment three, the embodiment of the present application four provides a kind of more specific sampling frequency offset estimation and compensation
System, main structure still can be found in shown in Fig. 4, which includes: symbol windowing unit 101, sampled value computing unit 102, changes
For computing unit 103, decision unit 104 and adjusting parameter determination unit 105, wherein
Symbol windowing unit 101 is obtained from data buffer storage for determining the windowing position of current sign according to windowing position
Take the sampled point of current sign；
Specifically, as shown in figure 5, Fig. 5 is a kind of structural representation for symbol windowing unit that the embodiment of the present application four provides
Figure, symbol windowing unit include:
First son windowing unit 201, is used for when current sign is initial symbol, using predeterminated position as current sign
Open a window position；
Second son windowing unit 202, for when current sign is not initial symbol, according to the windowing position of a upper symbol
The windowing position of current sign is determined with windowing adjusting parameter；
Sampled point acquiring unit 203, the windowing for being determined according to the first son windowing unit or the second son windowing unit
Position obtains the sampled point of current sign from data buffer storage.
Sampled value computing unit 102 calculates each symbol week after the value of the sampled point of current sign takes absolute value
Five equally spaced sampled values in phase；
Since the value of the sampled point of current sign is possible to as negative value, therefore, it is necessary to first by the sampled point of current sign
Value takes absolute value, then calculates five equally spaced sampled values in each symbol period.
The sampling point value for the GFSK symbol that windowing obtains is taken absolute value first, is then calculated in each GFSK symbol period
The sampled value of initial position, 1/4 position, 1/2 position, 3/4 position and end position totally five positions at equal intervals, respectively with S_
0 (i), S_1 (i), S_2 (i), S_3 (i), S_4 (i) indicate the sampled value of i-th of GFSK symbol.
Specifically, calculating five equally spaced sampled values in each symbol period using abs function in this application.
Unit 103 is iterated to calculate, for utilizing five equal interval sampling value iterative calculation the first judgement expression formulas and second
Adjudicate expression formula；
Wherein, the first judgement expression formula are as follows: E (j)=E (j-1)+S_2 (j)-(S_0 (j)+S_4 (j))/2, wherein (- 1) E
It is 0；
Second judgement expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0；
Wherein, j indicates GFSK symbol counter value, and the counting period of GFSK symbol counter is N, i.e., j value is 0 to N-1；
S_0 (j), S_1 (j), S_2 (j), S_3 (j), S_4 (j) indicate five equal interval sampling values of j-th of GFSK symbol, S_0 (j)
For the sampled value of initial position in GFSK symbol period, S_1 (j) is the sampled value of 1/4 position in GFSK symbol period, S_2 (j)
For the sampled value of 1/2 position in GFSK symbol period, S_3 (j) is the sampled value of 3/4 position in GFSK symbol period, S_4 (j)
For the sampled value of end position in GFSK symbol period.
Decision unit 104, for determining the need for carrying out sampling frequency offset compensation according to the first judgement expression formula；
Specifically, decision unit includes:
First judging unit, for being using the first judgement expression formula judgement when GFSK symbol counter value j is N-1
It is no that there are offsets caused by sampling frequency offset；
First determination unit, for when the value of the first judgement expression formula is less than or equal to preset threshold value, it is determined that need
Sampling frequency offset compensation is carried out, otherwise, is compensated without sampling frequency offset.
Adjusting parameter determination unit 105, for needing to carry out sampling frequency offset compensation when according to the first judgement expression formula determination
When, determine that windowing adjusting parameter is adjusted with split window position using the second judgement expression formula.
Specifically, adjusting parameter determination unit includes:
Second judgment unit, for judging whether the value of the second predicated expressions is greater than or equal to 0；
Second determination unit, for when the value of the second predicated expressions is greater than or equal to 0, then the adjusting parameter that opens a window to indicate
+ M sampled points of sign synchronization position adjustment；When the value of the second predicated expressions is less than 0, then the adjusting parameter that opens a window designated symbol
- M sampled points of sync bit adjustment；M is positive integer.
In addition, it should be noted that, the same or similar part can mutually refer between each embodiment of the application, in this Shen
Please in repeat no more.
Finally, it is to be noted that, herein, relational terms such as first and second and the like be used merely to by
One entity or operation are distinguished with another entity or operation, without necessarily requiring or implying these entities or operation
Between there are any actual relationship or orders.Moreover, the terms "include", "comprise" or its any other variant meaning
Covering non-exclusive inclusion, so that the process, method, article or equipment for including a series of elements not only includes that
A little elements, but also including other elements that are not explicitly listed, or further include for this process, method, article or
The intrinsic element of equipment.In the absence of more restrictions, the element limited by sentence "including a ...", is not arranged
Except there is also other identical elements in the process, method, article or apparatus that includes the element.
Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with other
The difference of embodiment, the same or similar parts in each embodiment may refer to each other.
The foregoing description of the disclosed embodiments makes professional and technical personnel in the field can be realized or use the application.
Various modifications to these embodiments will be readily apparent to those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the application.Therefore, the application
It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one
The widest scope of cause.
Claims (10)
1. a kind of sampling frequency offset estimation and compensation method, which is characterized in that this method comprises:
The windowing position for determining current sign obtains the sampled point of current sign according to the windowing position from data buffer storage；
After the value of the sampled point of the current sign is taken absolute value, five equally spaced samplings in each symbol period are calculated
Value；
Utilize the first judgement expression formula of five equal interval sampling values iterative calculation and the second judgement expression formula；
When needing to carry out sampling frequency offset compensation according to the first judgement expression formula is determining, the second judgement expression formula is utilized
Determine that windowing adjusting parameter is adjusted with split window position.
2. the method according to claim 1, wherein the windowing position of the determining current sign includes:
When the current sign is initial symbol, using predeterminated position as the windowing position of the current sign；
When the current sign is not initial symbol, according to the windowing position of a upper symbol and windowing adjusting parameter determination
The windowing position of current sign.
3. the method according to claim 1, wherein the first judgement expression formula are as follows: E (j)=E (j-1)+S_
2 (j)-(S_0 (j)+S_4 (j))/2, wherein E (- 1) is 0；
The second judgement expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0；
Wherein, j indicates GFSK symbol counter value, and the counting period of GFSK symbol counter is N, i.e., j value is 0 to N-1；S_0
(j), S_1 (j), S_2 (j), S_3 (j), S_4 (j) indicate five equal interval sampling values of j-th of GFSK symbol, and S_0 (j) is
The sampled value of initial position in GFSK symbol period, S_1 (j) are the sampled value of 1/4 position in GFSK symbol period, and S_2 (j) is
The sampled value of 1/2 position in GFSK symbol period, S_3 (j) are the sampled value of 3/4 position in GFSK symbol period, and S_4 (j) is
The sampled value of end position in GFSK symbol period.
4. method according to claim 1 to 3, which is characterized in that the first judgement expression formula, which determines, to be needed
Carrying out frequency deviation compensation includes:
When GFSK symbol counter value j is N-1, judging whether there is sampling frequency offset using the first judgement expression formula causes
Offset；
When the value of the first judgement expression formula is less than or equal to preset threshold value, it is determined that need to carry out sampling frequency offset compensation.
5. according to the method described in claim 4, it is characterized in that, described determine that windowing is adjusted using the second judgement expression formula
Whole parameter includes:
Judge whether the value of second predicated expressions is greater than or equal to 0；
When the value of second predicated expressions is greater than or equal to 0, then the windowing adjusting parameter designated symbol sync bit
+ M sampled points of adjustment；When the value of second predicated expressions is less than 0, then the windowing adjusting parameter designated symbol is synchronous
- M sampled points of position adjustment；The M is positive integer.
6. a kind of estimation of sampling frequency offset and compensation system, which is characterized in that the system includes:
Symbol windowing unit is obtained from data buffer storage for determining the windowing position of current sign according to the windowing position
The sampled point of current sign；
Sampled value computing unit calculates each symbol period after the value of the sampled point of the current sign takes absolute value
Interior five equally spaced sampled values；
Unit is iterated to calculate, for utilizing the first judgement expression formula of five equal interval sampling values iterative calculation and the second judgement
Expression formula；
Decision unit, for determining the need for carrying out sampling frequency offset compensation according to the first judgement expression formula；
Adjusting parameter determination unit, for when according to it is described first judgement expression formula determine need to carry out sampling frequency offset compensation when,
Determine that windowing adjusting parameter is adjusted with split window position using the second judgement expression formula.
7. system according to claim 6, which is characterized in that symbol windowing unit includes:
First son windowing unit, is used for when the current sign is initial symbol, using predeterminated position as the current sign
Windowing position；
Second son windowing unit, for when the current sign is not initial symbol, according to the windowing position of a upper symbol and
Windowing adjusting parameter determines the windowing position of the current sign；
Sampled point acquiring unit, the windowing for being determined according to the first son windowing unit or the second son windowing unit
Position obtains the sampled point of current sign from data buffer storage.
8. system according to claim 6, which is characterized in that the first judgement expression formula are as follows: E (j)=E (j-1)+S_
2 (j)-(S_0 (j)+S_4 (j))/2, wherein E (- 1) is 0；
The second judgement expression formula are as follows: F (j)=F (j-1)+S_1 (j)-S_3 (j), wherein F (- 1) is 0；
Wherein, j indicates GFSK symbol counter value, and the counting period of GFSK symbol counter is N, i.e., j value is 0 to N-1；S_0
(j), S_1 (j), S_2 (j), S_3 (j), S_4 (j) indicate five equal interval sampling values of j-th of GFSK symbol, and S_0 (j) is
The sampled value of initial position in GFSK symbol period, S_1 (j) are the sampled value of 1/4 position in GFSK symbol period, and S_2 (j) is
The sampled value of 1/2 position in GFSK symbol period, S_3 (j) are the sampled value of 3/4 position in GFSK symbol period, and S_4 (j) is
The sampled value of end position in GFSK symbol period.
9. according to system described in claim 6-8 any one, which is characterized in that the decision unit includes:
First judging unit, for being using the first judgement expression formula judgement when GFSK symbol counter value j is N-1
It is no that there are offsets caused by sampling frequency offset；
First determination unit, for when first judgement expression formula value be less than or equal to preset threshold value when, it is determined that need into
Otherwise the compensation of row sampling frequency offset is compensated without sampling frequency offset.
10. system according to claim 9, which is characterized in that the adjusting parameter determination unit includes:
Second judgment unit, for judging whether the value of second predicated expressions is greater than or equal to 0；
Second determination unit, for when the value of second predicated expressions is greater than or equal to 0, then the windowing adjusting parameter
+ M sampled points of designated symbol sync bit adjustment；When the value of second predicated expressions is less than 0, then the windowing adjustment
- M sampled points of parameter indicator sync bit adjustment；The M is positive integer.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114978830A (en) * | 2022-05-13 | 2022-08-30 | 广芯微电子(苏州)有限公司 | Frequency offset estimation method, device and medium applied to GFSK digital receiver |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030142761A1 (en) * | 2002-01-30 | 2003-07-31 | Hung-Kun Chen | Frequency offset estimation apparatus for intersymbol interference channels |
| CN101022442A (en) * | 2007-01-16 | 2007-08-22 | 西安交通大学 | Joint time synchronizing and frequency-offset estimating method in OFDM system |
| CN102075485A (en) * | 2011-01-20 | 2011-05-25 | 深圳市阿派斯实业有限公司 | Sampling clock synchronization method for orthogonal frequency division multiplexing (OFDM) system |
| CN102480452A (en) * | 2010-11-26 | 2012-05-30 | 中国科学院微电子研究所 | Carrier frequency synchronous circuit and method of OFDM (Orthogonal Frequency Division Multiplexing) system |
| CN104168224A (en) * | 2013-05-20 | 2014-11-26 | 普天信息技术研究院有限公司 | Frequency offset estimation and compensation method |
| CN106534023A (en) * | 2016-09-20 | 2017-03-22 | 西安电子科技大学 | Timing and carrier united synchronization method of MQAM in non-cooperative communication |
| US20170180171A1 (en) * | 2015-12-18 | 2017-06-22 | Qualcomm Incorporated | Frequency synchronization of convolutionally coded gfsk signals |
-
2018
- 2018-11-30 CN CN201811452250.3A patent/CN109450837B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030142761A1 (en) * | 2002-01-30 | 2003-07-31 | Hung-Kun Chen | Frequency offset estimation apparatus for intersymbol interference channels |
| CN101022442A (en) * | 2007-01-16 | 2007-08-22 | 西安交通大学 | Joint time synchronizing and frequency-offset estimating method in OFDM system |
| CN102480452A (en) * | 2010-11-26 | 2012-05-30 | 中国科学院微电子研究所 | Carrier frequency synchronous circuit and method of OFDM (Orthogonal Frequency Division Multiplexing) system |
| CN102075485A (en) * | 2011-01-20 | 2011-05-25 | 深圳市阿派斯实业有限公司 | Sampling clock synchronization method for orthogonal frequency division multiplexing (OFDM) system |
| CN104168224A (en) * | 2013-05-20 | 2014-11-26 | 普天信息技术研究院有限公司 | Frequency offset estimation and compensation method |
| US20170180171A1 (en) * | 2015-12-18 | 2017-06-22 | Qualcomm Incorporated | Frequency synchronization of convolutionally coded gfsk signals |
| CN106534023A (en) * | 2016-09-20 | 2017-03-22 | 西安电子科技大学 | Timing and carrier united synchronization method of MQAM in non-cooperative communication |
Non-Patent Citations (1)
| Title |
|---|
| 郑婧怡，王志华等: ""带频偏校准的GMSK解调器设计与实现"", 《通信与网络》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114978830A (en) * | 2022-05-13 | 2022-08-30 | 广芯微电子(苏州)有限公司 | Frequency offset estimation method, device and medium applied to GFSK digital receiver |
| CN114978830B (en) * | 2022-05-13 | 2023-10-20 | 广芯微电子(苏州)有限公司 | Frequency offset estimation method, device and medium applied to GFSK digital receiver |
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