CN109361634A - The compensation method and system of receiver carrier wave frequency deviation - Google Patents
The compensation method and system of receiver carrier wave frequency deviation Download PDFInfo
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- CN109361634A CN109361634A CN201811390763.6A CN201811390763A CN109361634A CN 109361634 A CN109361634 A CN 109361634A CN 201811390763 A CN201811390763 A CN 201811390763A CN 109361634 A CN109361634 A CN 109361634A
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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
- H04L27/10—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
- H04L2027/0024—Carrier regulation at the receiver end
- H04L2027/0026—Correction of carrier offset
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Abstract
The invention discloses a kind of compensation methodes of receiver carrier wave frequency deviation, comprising: when receiving target packet, obtains the payload data in the target packet；Obtain the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation method, no longer Nonlinear Transformation in Frequency Offset Estimation is carried out for shorter lead code, the Nonlinear Transformation in Frequency Offset Estimation value obtained according to first compensation circuit, carrier wave frequency deviation compensation is carried out to the payload data in the target packet, the length of the payload data is greater than the length of the lead code, it is easy to detect, avoids influence of the change in gain to data link of analog radio frequency front-end circuit.
Description
Technical field
The present invention relates to the compensation method of wireless communication technology field more particularly to a kind of receiver carrier wave frequency deviation and it is
System.
Background technique
Frequency shift keying (Frequency-Shift-Keying, abbreviation FSK) or GFSK Gaussian Frequency Shift Keying (Gaussian-
Frequency-Shift-Keying, abbreviation GFSK) it is a kind of very widely used digital modulation mode, have and realizes letter
It is single, antinoise and the preferable feature of anti-decay property.Since (G) FSK is a kind of frequency debud mode, carrier wave frequency deviation pair
Equipment performance based on (G) FSK modulation mode has large effect, can reduce the receptivity of receiver, or even make to receive
Machine can not correctly detect the information received.In order to improve the receptivity of receiver, system needs to mend carrier wave frequency deviation
It repays.In the prior art, it will usually average to the lead code in the received data packet of receiver, to estimate the load of system
Wave frequency is inclined and compensates.
Inventor carries out the compensation method of existing carrier wave frequency deviation the study found that after antenna receives carrier signal,
The automatic gain control circuit of analog radio frequency front end needs certain convergence time, when the change in gain of front end, can cause
The phase distortion of signal causes (G) fsk signal waveform of frequency domain burr occur；On the other hand, the duration of lead code is general
Shorter, the shorter lead code of use estimates carrier wave frequency deviation, first is that being not easy to detect lead code, second is that the frequency domain mean value of lead code
It is not enough to smooth out the noise of signal, this is especially apparent under low signal-to-noise ratio.
Summary of the invention
In view of this, the present invention provides the compensation method and system of a kind of receiver carrier wave frequency deviation, it is existing to solve
In technology after antenna receives carrier signal, when the automatic gain control circuit of analog radio frequency front end needs certain convergence
Between, when the change in gain of front end, the phase distortion of signal can be caused, (G) fsk signal waveform of frequency domain is caused hair occur
Thorn；On the other hand, the duration of lead code is generally shorter, and the shorter lead code of use estimates carrier wave frequency deviation, first is that being not easy
Lead code is detected, second is that the problem of frequency domain mean value of lead code is not enough to smooth out the noise of signal.Concrete scheme is as follows:
A kind of compensation method of receiver carrier wave frequency deviation, including
When receiving target packet, the payload data in the target packet is obtained；
Obtain the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；
Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
Above-mentioned method optionally obtains the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit, comprising:
The payload data is subjected to down-sampled filtering processing, obtains the first time-domain signal；
IF process is carried out to first time-domain signal, obtains the second time-domain signal；
It is demodulated after carrying out channel filtering to second time-domain signal, obtains frequency-region signal；
The frequency-region signal is passed to the first compensation circuit to calculate；
By calculated result by exporting the Nonlinear Transformation in Frequency Offset Estimation value after loop filter and controller.
The frequency-region signal is optionally passed to the first compensation circuit and calculated by above-mentioned method, comprising:
Obtain symbolic integration/sampling unit output sampled value in first compensation circuit；
According to the sampled value, the DC component that first frequency-region signal includes is estimated；
The DC component is passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula to calculate；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission
Rate, d are DC component.
A kind of compensation system of receiver carrier wave frequency deviation, comprising:
First obtains module, for when receiving target packet, obtaining the payload in the target packet
Data；
Second obtains module, for obtaining the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；
First compensating module, for carrying out carrier wave frequency deviation to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value
Compensation.
Above-mentioned system, optionally, the second acquisition module includes:
Down-sampled unit obtains the first time-domain signal for the payload data to be carried out down-sampled filtering processing；
Intermediate frequency unit is removed, for carrying out IF process to first time-domain signal, obtains the second time-domain signal；
Demodulating unit obtains frequency-region signal for demodulating after carrying out channel filtering to second time-domain signal；
First computing unit is calculated for the frequency-region signal to be passed to the first compensation circuit；
Output unit is transmitted, for estimating calculated result by exporting the carrier wave frequency deviation after loop filter and controller
Evaluation.
A kind of compensation method of receiver carrier wave frequency deviation, comprising:
When receiving target packet, the payload data in the target packet is obtained；
The payload is handled, frequency-region signal is obtained；
The frequency-region signal is passed into the second compensation circuit, obtains Nonlinear Transformation in Frequency Offset Estimation value；
Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
Above-mentioned method optionally handles the payload, obtains frequency-region signal, comprising:
The payload data is subjected to down-sampled filtering processing, obtains the first time-domain signal；
IF process is carried out to first time-domain signal, obtains the second time-domain signal；
It is demodulated after carrying out channel filtering to second time-domain signal, obtains the frequency-region signal.
The frequency-region signal is optionally passed to the second compensation circuit, obtains Nonlinear Transformation in Frequency Offset Estimation by above-mentioned method
Value, comprising:
Obtain symbolic integration/sampling unit output sampled value in second compensation circuit；
According to the sampled value, the DC component that second frequency-region signal includes is estimated；
The DC component is passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula to calculate；
Calculated result is subjected to loop filtering, obtains the Nonlinear Transformation in Frequency Offset Estimation value；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission
Rate, d are DC component.
A kind of compensation system of receiver carrier wave frequency deviation, comprising:
Third obtains module, for when receiving target packet, obtaining the payload in the target packet
Data；
Processing module obtains frequency-region signal for handling the payload；
Transfer module obtains Nonlinear Transformation in Frequency Offset Estimation value for the frequency-region signal to be passed to the second compensation circuit；
Second compensating module, for carrying out carrier wave frequency deviation to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value
Compensation.
Above-mentioned system, optionally, the transfer module includes:
Acquiring unit, for obtaining the symbolic integration in second compensation circuit/sampling unit output sampled value；
Estimation unit, for estimating the DC component that second frequency-region signal includes according to the sampled value；
Second computing unit, by passing to the DC component based on preset Nonlinear Transformation in Frequency Offset Estimation expression formula carries out
It calculates；
Filter unit obtains the Nonlinear Transformation in Frequency Offset Estimation value for calculated result to be carried out loop filtering；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission
Rate, d are DC component.
Compared with prior art, the present invention includes the following advantages:
The invention discloses a kind of compensation methodes of receiver carrier wave frequency deviation, comprising: when receiving target packet, obtains
The payload data in the target packet is taken, and obtains the carrier wave frequency deviation being calculated according to the first compensation circuit and estimates
Evaluation carries out carrier wave frequency deviation compensation to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation method,
No longer Nonlinear Transformation in Frequency Offset Estimation, the Nonlinear Transformation in Frequency Offset Estimation obtained according to first compensation circuit are carried out for shorter lead code
Value carries out carrier wave frequency deviation compensation to the payload data in the target packet, and the length of the payload data is big
In the length of the lead code, it is easy to detect, avoids influence of the change in gain to data link of analog radio frequency front-end circuit.
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
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
It obtains other drawings based on these drawings.
Fig. 1 is a kind of receiver carrier wave frequency deviation compensation method flow chart disclosed in the embodiment of the present application；
Fig. 2 is a kind of structural schematic diagram of data packet disclosed in the embodiment of the present application；
Fig. 3 is a kind of receiver carrier wave frequency deviation compensation method execution schematic diagram disclosed in the embodiment of the present application；
Fig. 4 is a kind of compensation circuit schematic diagram disclosed in the embodiment of the present application；
Fig. 5 is a kind of receiver carrier wave frequency deviation compensation system structural block diagram disclosed in the embodiment of the present application；
Fig. 6 is a kind of another structural block diagram of receiver Nonlinear Transformation in Frequency Offset Estimation system disclosed in the embodiment of the present application；
Fig. 7 is a kind of another flow chart of receiver carrier wave frequency deviation compensation method disclosed in the embodiment of the present application；
Fig. 8 is a kind of another execution schematic diagram of receiver carrier wave frequency deviation compensation method disclosed in the embodiment of the present application；
Fig. 9 is a kind of another schematic diagram of compensation circuit disclosed in the embodiment of the present application；
Figure 10 is a kind of another structural block diagram of receiver Nonlinear Transformation in Frequency Offset Estimation system disclosed in the embodiment of the present application；
Figure 11 is a kind of another structural block diagram of receiver Nonlinear Transformation in Frequency Offset Estimation system disclosed in the embodiment of the present application.
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.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
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 present invention.Therefore, of the invention
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.
The invention discloses the compensation method and system of a kind of receiver carrier wave frequency deviation, carrier wave frequency deviation can reduce receiver
Receptivity, or even make receiver that can not correctly detect the information received needs pair to improve the receptivity of receiver
Carrier wave frequency deviation compensates, and is said by taking the compensation of the carrier wave frequency deviation based on (G) FSK modulation mode as an example in the embodiment of the present invention
Bright, the mode of compensation is divided into time domain compensation and two kinds of frequency domain compensation, wherein the compensation method process of time domain scale intercarrier frequency deviation
As shown in Figure 1, comprising steps of
S101, when receiving target packet, obtain the payload data in the target packet；
In the embodiment of the present invention, received receiver is continuous data packet, the data packet that currently will need to compensate
It is defined as target packet, wherein the structural schematic diagram of the target packet is as shown in Figure 2, comprising: lead code, synchronously
Location and payload.Lead code is generally made of ' 0 ', ' the 1 ' of 4~32 bits alternate bit stream, for example, Bluetooth Low Energy system
The packet header of system data as 8 bits are constituted.The target packet and local synchronization address sequence are subjected to cross-correlation, led to
The peak value for crossing cross correlation results obtains the initial position of payload data in the target packet, according to the initial position
Determine the payload data.
S102, the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit is obtained；
In the embodiment of the present invention, first compensation circuit is by being turned to after payload progress relevant treatment by time domain
To frequency domain, and frequency-region signal is passed into first compensation circuit and is calculated, and is obtained after calculated result is handled
Nonlinear Transformation in Frequency Offset Estimation value obtains the Nonlinear Transformation in Frequency Offset Estimation value.Wherein, first compensation circuit includes: symbol detection
With data-aided Nonlinear Transformation in Frequency Offset Estimation unit.
S103, carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
In the embodiment of the present invention, the Nonlinear Transformation in Frequency Offset Estimation value is in frequency domain, it is preferred that according to the preset carrier frequency
Inclined estimated expression:
Wherein, h is modulation index, and R is transmission rate, and d is DC component.
Wherein, the Nonlinear Transformation in Frequency Offset Estimation value is transformed into time domain, is then exported using loop filter, it is preferred that
The loop filter of the loop filter first-order loop filter, second order or higher order.If time-domain sampling rate is fs, then
The phase-accumulated amount Δ θ that controller generates can be expressed as formula (2):
Δ f' is the output valve that time domain carrier wave frequency deviation Δ f passes through loop filter.
The plural correcting frequency deviation signal that time domain carrier wave frequency deviation generates can be expressed as formula (3):
The complex signal is multiplied with the complex base band signal that input is come in, wherein the complex base band signal is the mesh
Signal of the data packet by desampling fir filter and after going IF process is marked to get the compensated time-domain signal of carrier wave frequency deviation is arrived.
The invention discloses a kind of compensation methodes of receiver carrier wave frequency deviation, comprising: when receiving target packet, obtains
Take the payload data in the target packet；Obtain the Nonlinear Transformation in Frequency Offset Estimation being calculated according to the first compensation circuit
Value；Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation method, no
Nonlinear Transformation in Frequency Offset Estimation is carried out for shorter lead code again, according to the Nonlinear Transformation in Frequency Offset Estimation value that first compensation circuit obtains,
Carrier wave frequency deviation compensation is carried out to the payload data in the target packet, the length of the payload data is greater than institute
The length for stating lead code is easy to detect, and avoids influence of the change in gain to data link of analog radio frequency front-end circuit.
In the embodiment of the present invention, the concrete methods of realizing based on above-mentioned time domain compensation method is as shown in figure 3, what the figure was shown
It is traditional (G) FSK low intermediate frequency receiver data path, it is preferred that by taking the estimation and compensation circuit of carrier wave frequency deviation are stated in exhibition as an example
It is illustrated, however not excluded that the data path can use other receiver architecture substitutions.It is as follows to sketch data path: receiver day
After line receives aerial signal, by the filtering of analog radio frequency front end, it is amplified into ADC and is converted to digital signal, in numeric field
In, continue to be filtered the data received, is down-sampled, intermediate frequency is then gone to become zero intermediate frequency signals, signal is name at this time
On zero intermediate frequency signals because there are also carrier wave frequency deviations not to remove for the signal.Because can also pass through a carrier wave in time-domain filtering
The compensation circuit of frequency deviation.Then signal filters out out of band signal by channel model, then is converted to frequency domain letter by fsk demodulator
Number, enter first compensation circuit of (G) fsk signal later, (G) FSK is just changed by two-way I, Q signal after fsk demodulator
For the signal all the way of frequency domain.
Generally, FSK demodulation output is normalized between ± 1 ,+1 represents maximum frequency modulation, -1 represent it is the smallest
Frequency modulation.If (G) fsk signal data rate is R, modulation index h, then maximum modulation frequency deviation is shown in formula (4):
If receiver received signal has carrier wave frequency deviation Δ fc, then, carrier wave frequency deviation DC component d caused by frequency domain
It can be indicated with formula (5):
Alternatively, the expression formula of available Nonlinear Transformation in Frequency Offset Estimation value, such as formula (1).
After the payload of the target packet is converted to frequency domain (G) fsk signal, it is input to the first compensation electricity
Road, wherein the schematic diagram of first compensation circuit is as shown in figure 4, be input to symbol inspection for the payload for being switched to frequency domain
Unit is surveyed, symbol detection is by according to the positive and negative values of each symbol optimum sampling point, or the integral of entire symbol sampler point
Value is judged as bit ' 0 ' or ' 1 '；Wherein, the data-aided Nonlinear Transformation in Frequency Offset Estimation unit is sought to according to symbol detection
The numerical value of sampled point estimates a carrier wave frequency deviation in the testing result of unit and each symbol, by loop filter
Local signal generator is arrived with feedback after controller, carries out carrier wave frequency deviation compensation, wherein include in carrier wave frequency deviation compensating unit:
Frequency mixer and local signal generator.Preferably, the ring of the loop filter first-order loop filter, second order or higher order
Path filter.Carrier wave frequency deviation compensating unit, which is used to compensate the frequency domain symbol value as caused by carrier wave frequency deviation, integrally to be moved up or down,
To increase the accuracy rate of symbol detection, the receptivity of receiver is improved.
Based on a kind of above-mentioned receiver carrier wave frequency deviation compensation method, invention provides a kind of receiver carrier wave frequency deviations
The structural block diagram of compensation system, the compensation system is as shown in Figure 5, comprising:
First obtains module 201, and second obtains module 202 and the first compensating module 203.
Wherein,
Described first obtains module 201, for when receiving target packet, obtaining having in the target packet
Imitate load data；
Described second obtains module 202, for obtaining the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；
First compensating module 203, for being carried out according to the Nonlinear Transformation in Frequency Offset Estimation value to the payload data
Carrier wave frequency deviation compensation.
The invention discloses a kind of compensation systems of receiver carrier wave frequency deviation, comprising: when receiving target packet, obtains
Take the payload data in the target packet；Obtain the Nonlinear Transformation in Frequency Offset Estimation being calculated according to the first compensation circuit
Value；Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation system, no
Nonlinear Transformation in Frequency Offset Estimation is carried out for shorter lead code again, according to the Nonlinear Transformation in Frequency Offset Estimation value that first compensation circuit obtains,
Carrier wave frequency deviation compensation is carried out to the payload data in the target packet, the length of the payload data is greater than institute
The length for stating lead code is easy to detect, and avoids influence of the change in gain to data link of analog radio frequency front-end circuit.
In the embodiment of the present invention, structural block diagram such as Fig. 6 of the second acquisition module 202 includes:
Down-sampled unit 204 removes intermediate frequency unit 205, demodulating unit 206, computing unit 207 and transmitting output unit 208.
Wherein,
The down-sampled unit 204, for the payload data to be carried out down-sampled filtering processing, when obtaining first
Domain signal；
It is described to remove intermediate frequency unit 205, for carrying out IF process to first time-domain signal, obtain the second time domain letter
Number；
The demodulating unit 206 obtains frequency domain letter for demodulating after carrying out channel filtering to second time-domain signal
Number；
The computing unit 207 is calculated for the frequency-region signal to be passed to the first compensation circuit；
The transmitting output unit 208, for exporting the load after calculated result is passed through loop filter and controller
The inclined estimated value of wave frequency.
In the embodiment of the present invention, the compensation method process of frequency domain intercarrier frequency deviation is as shown in fig. 7, comprises step:
S301, when receiving target packet, obtain the payload data in the target packet；
In the embodiment of the present invention, received receiver is continuous data packet, the data packet that currently will need to compensate
It is defined as target packet, wherein the structural schematic diagram of the target packet is as shown in Figure 2, comprising: lead code, synchronously
Location and payload.Lead code is generally made of ' 0 ', ' the 1 ' of 4~32 bits alternate bit stream, for example, Bluetooth Low Energy system
The packet header of system data as 8 bits are constituted.The target packet is parsed, obtains in the target packet and includes
Payload, wherein the method flow of payload data obtained in the target packet and obtaining for S201-S203
It takes process identical, repeats no more.
S302, the payload is handled, obtains frequency-region signal；
In the embodiment of the present invention, down-sampled filtering processing is carried out to the payload, goes IF process and channel filtering
After demodulate, obtain frequency-region signal.
S303, the frequency-region signal is passed into the second compensation circuit, obtains Nonlinear Transformation in Frequency Offset Estimation value；
In the embodiment of the present invention, the frequency-region signal is passed into second compensation circuit and is calculated, obtained described
Nonlinear Transformation in Frequency Offset Estimation value.Wherein, second compensation circuit includes: symbol detection, carrier wave frequency deviation compensating unit and data
The Nonlinear Transformation in Frequency Offset Estimation unit of auxiliary,
S304, carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
In the embodiment of the present invention, the Nonlinear Transformation in Frequency Offset Estimation value is fed back into the symbol detection in second compensation circuit
Unit carries out carrier wave frequency deviation compensation to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
The invention discloses a kind of compensation methodes of receiver carrier wave frequency deviation, comprising: right when receiving target packet
The payload is handled, and frequency-region signal is obtained；The frequency-region signal is passed into the second compensation circuit, obtains carrier frequency
Inclined estimated value；Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation
Method no longer carries out Nonlinear Transformation in Frequency Offset Estimation, the carrier wave frequency deviation obtained according to second compensation circuit for shorter lead code
Estimated value carries out carrier wave frequency deviation compensation, the length of the payload data to the payload data in the target packet
Degree is greater than the length of the lead code, is easy to detect, avoids the change in gain of analog radio frequency front-end circuit to data link
It influences.
In the embodiment of the present invention, the concrete methods of realizing based on above-mentioned frequency domain compensating method is as shown in figure 8, what the figure was shown
It is traditional (G) FSK low intermediate frequency receiver data path, it is preferred that by taking the estimation and compensation circuit of carrier wave frequency deviation are stated in exhibition as an example
It is illustrated, however not excluded that the data path can use other receiver architecture substitutions.It is as follows to sketch data path: receiver day
After line receives aerial signal, by the filtering of analog radio frequency front end, it is amplified into ADC and is converted to digital signal, in numeric field
In, continue to be filtered the data received, is down-sampled, intermediate frequency is then gone to become zero intermediate frequency signals, signal is name at this time
On zero intermediate frequency signals because there are also carrier wave frequency deviations not to remove for the signal.Then signal filters out outside band by channel model
Signal, then frequency-region signal is converted to by fsk demodulator, enter second compensation circuit of (G) fsk signal later, (G) FSK passes through
After fsk demodulator, just it is changed into the signal all the way of frequency domain by two-way I, Q signal.
Generally, FSK demodulation output is normalized between ± 1 ,+1 represents maximum frequency modulation, -1 represent it is the smallest
Frequency modulation.If (G) fsk signal data rate is R, modulation index h, then maximum modulation frequency deviation is shown in formula (4).
If receiver received signal has carrier wave frequency deviation Δ fc, then, carrier wave frequency deviation DC component d caused by frequency domain
It can be indicated with formula (5).
Alternatively, the expression formula of available Nonlinear Transformation in Frequency Offset Estimation value, such as formula (1).
After the payload of the target packet is converted to frequency domain (G) fsk signal, it is input to the second compensation electricity
Road, wherein the schematic diagram of second compensation circuit is as shown in figure 9, be input to symbol inspection for payload of the switching with frequency domain
Unit is surveyed, symbol detection is by according to the positive and negative values of each symbol optimum sampling point, or the integral of entire symbol sampler point
Value is judged as bit ' 0 ' or ' 1 ', and corresponding integrated value is input to the data-aided Nonlinear Transformation in Frequency Offset Estimation unit and load
Feedback arrives symbolic integration/sampling unit input terminal after wave frequency offset compensation element, wherein carrier wave frequency deviation compensating unit is used to compensate
The value of symbol as caused by carrier wave frequency deviation integrally moves up or down, to increase the accuracy rate of symbol detection, improves receiver
Receptivity.
Wherein, in frequency domain and time domain compensation method, the estimated value of carrier wave frequency deviation DC component d caused by frequency domain can
To be accomplished by the following way:
Symbolic integration: the over-sampling rate of conventional letter is Ns, the input of symbolic integration unit is xi, then symbol integral unit
Output such as formula (6) shown in:
Optimum sampling point: the optimum sampling point position of symbol is obtained by synchronous circuit, which can be understood as accordingly according with
The sampled value ε of number middle time pointj。
When practical application, in the estimating circuit of carrier wave frequency deviation, any one of both the above mode can be used.
The estimated value of DC component d isIt is input to judging unit, the output y of judging unitjIt can be by formula (7) come table
Show:
The output of frequency deviation estimating unit, that is, estimated value of the carrier wave frequency deviation on frequency domainIt can be indicated with formula (8):
In the embodiment of the present invention, in the compensation method of above-mentioned time domain and frequency domain, it is preferred that in the time domain, channel filtering
The design of device can generally be designed the band width in physical close to baseband signal as far as possible, can filter out more out-of-band noises in this way,
Channel selectivity also can be more preferable simultaneously, however carrier wave frequency deviation can make the passband for deviateing channel model on one side of signal, so that
The energy of signal is lost, to reduce the receptivity of receiver.Therefore, in time domain compensation carrier wave frequency deviation, to a certain degree
On can obtain compared to the better receiver performance of frequency domain compensation；But, time domain compensation carrier wave frequency deviation also has a shortcoming: one
It is that time domain compensation needs a frequency mixer to need to increase a plural local signal generator and one in the digital domain
Complex multiplier considerably increases the complexity and cost of circuit；Second is that being prolonged using time domain compensation from the loop of frequency domain to time domain
Larger late, the stability of loop is slightly worse.And the design of frequency domain compensation carrier wave frequency deviation circuit is more succinct, directly subtracts from input terminal
Corresponding estimated value of the carrier wave frequency deviation on frequency domain.In general, when carrier wave frequency deviation is larger, (equipment uses frequency stability
Lower crystal) when, use the frequency bias compensation method of time domain；And when carrier wave frequency deviation is smaller, (equipment is higher using frequency stability
Crystal) when, use the frequency bias compensation method of frequency domain.
In the embodiment of the present invention, based on the compensation method of above-mentioned receiver carrier wave frequency deviation, in the embodiment of the present invention, also mention
Supply a kind of compensation system of receiver carrier wave frequency deviation, wherein the structural block diagram of the compensation system is as shown in Figure 10, comprising:
Third obtains module 401, processing module 402, transfer module 403 and the second compensating module 404.
Wherein,
The third obtains module 401, for when receiving target packet, obtaining having in the target packet
Imitate load data；
The processing module 402 obtains frequency-region signal for handling the payload；
The transfer module 403 obtains Nonlinear Transformation in Frequency Offset Estimation for the frequency-region signal to be passed to the second compensation circuit
Value；
Second compensating module 404, for being carried out according to the Nonlinear Transformation in Frequency Offset Estimation value to the payload data
Carrier wave frequency deviation compensation.
The invention discloses a kind of compensation systems of receiver carrier wave frequency deviation, comprising: right when receiving target packet
The payload is handled, and frequency-region signal is obtained；The frequency-region signal is passed into the second compensation circuit, obtains carrier frequency
Inclined estimated value；Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.Above-mentioned compensation
System no longer carries out Nonlinear Transformation in Frequency Offset Estimation, the carrier wave frequency deviation obtained according to second compensation circuit for shorter lead code
Estimated value carries out carrier wave frequency deviation compensation, the length of the payload data to the payload data in the target packet
Degree is greater than the length of the lead code, is easy to detect, avoids the change in gain of analog radio frequency front-end circuit to data link
It influences.
Second compensating module, for carrying out carrier wave frequency deviation to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value
Compensation.
In the embodiment of the present invention, as shown in figure 11, the transfer module 403 includes:
Acquiring unit 405, estimation unit 406, the second computing unit 407 and filter unit 408.
Wherein,
The acquiring unit 405 is adopted for obtaining the symbolic integration in second compensation circuit/sampling unit output
Sample value；
The estimation unit 406, for according to the sampled value, estimating the direct current point that second frequency-region signal includes
Amount；
Second computing unit 407, for the DC component to be passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula
It is calculated；
The filter unit 408 obtains the Nonlinear Transformation in Frequency Offset Estimation value for calculated result to be carried out loop filtering；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission
Rate, d are DC component.
It should be noted that all the embodiments in this specification are described in a progressive manner, each embodiment weight
Point explanation is the difference from other embodiments, and the same or similar parts between the embodiments can be referred to each other.
For device class embodiment, since it is basically similar to the method embodiment, so being described relatively simple, related place ginseng
See the part explanation of embodiment of the method.
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 perhaps or operation with another entity or operate distinguish and not necessarily require or or imply these entities or
There are any this actual relationship or or sequences between operation.Moreover, the terms "include", "comprise" or or its it is any its
He is intended to non-exclusive inclusion by variant, so that including process, method, article or or the equipment of a series of elements
Include not only those elements, but also including other elements that are not explicitly listed, or or further includes for this process, side
Method, article or or the intrinsic element of equipment.In the absence of more restrictions, being limited by sentence "including a ..."
Element, it is not excluded that include the process, method of the element, article or or equipment in identical want there is also other
Element.
For convenience of description, it is divided into various units when description apparatus above with function to describe respectively.Certainly, implementing this
The function of each unit can be realized in the same or multiple software and or hardware when invention.
As seen through the above description of the embodiments, those skilled in the art can be understood that the present invention can
It realizes by means of software and necessary general hardware platform.Based on this understanding, technical solution of the present invention essence
It is upper or or say that the part that contributes to existing technology can be embodied in the form of software products, which produces
Product can store in storage medium, such as ROM/RAM, magnetic disk, CD, including some instructions are with so that a computer is set
It is standby (can be personal computer, server, either or the network equipment etc.) execute each embodiment of the present invention or or embodiment
Certain parts described in method.
The compensation method and system of a kind of receiver carrier wave frequency deviation provided by the present invention are described in detail above,
Used herein a specific example illustrates the principle and implementation of the invention, and the explanation of above embodiments is only used
In facilitating the understanding of the method and its core concept of the invention；At the same time, for those skilled in the art, according to the present invention
Thought, there will be changes in the specific implementation manner and application range, in conclusion the content of the present specification should not be construed as
Limitation of the present invention.
Claims (10)
1. a kind of compensation method of receiver carrier wave frequency deviation characterized by comprising
When receiving target packet, the payload data in the target packet is obtained；
Obtain the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；
Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
2. the method according to claim 1, wherein obtaining the carrier frequency being calculated according to the first compensation circuit
Inclined estimated value, comprising:
The payload data is subjected to down-sampled filtering processing, obtains the first time-domain signal；
IF process is carried out to first time-domain signal, obtains the second time-domain signal；
It is demodulated after carrying out channel filtering to second time-domain signal, obtains frequency-region signal；
The frequency-region signal is passed to the first compensation circuit to calculate；
By calculated result by exporting the Nonlinear Transformation in Frequency Offset Estimation value after loop filter and controller.
3. being carried out the method according to claim 1, wherein the frequency-region signal is passed to the first compensation circuit
It calculates, comprising:
Obtain symbolic integration/sampling unit output sampled value in first compensation circuit；
According to the sampled value, the DC component that first frequency-region signal includes is estimated；
The DC component is passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula to calculate；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission speed
Rate, d are DC component.
4. a kind of compensation system of receiver carrier wave frequency deviation characterized by comprising
First obtains module, for when receiving target packet, obtaining the payload data in the target packet；
Second obtains module, for obtaining the Nonlinear Transformation in Frequency Offset Estimation value being calculated according to the first compensation circuit；
First compensating module, for carrying out carrier wave frequency deviation benefit to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value
It repays.
5. system according to claim 4, which is characterized in that described second, which obtains module, includes:
Down-sampled unit obtains the first time-domain signal for the payload data to be carried out down-sampled filtering processing；
Intermediate frequency unit is removed, for carrying out IF process to first time-domain signal, obtains the second time-domain signal；
Demodulating unit obtains frequency-region signal for demodulating after carrying out channel filtering to second time-domain signal；
First computing unit is calculated for the frequency-region signal to be passed to the first compensation circuit；
Output unit is transmitted, for exporting the Nonlinear Transformation in Frequency Offset Estimation after calculated result is passed through loop filter and controller
Value.
6. a kind of compensation method of receiver carrier wave frequency deviation characterized by comprising
When receiving target packet, the payload data in the target packet is obtained；
The payload is handled, frequency-region signal is obtained；
The frequency-region signal is passed into the second compensation circuit, obtains Nonlinear Transformation in Frequency Offset Estimation value；
Carrier wave frequency deviation compensation is carried out to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value.
7. according to the method described in claim 6, obtain frequency-region signal it is characterized in that, handle the payload,
Include:
The payload data is subjected to down-sampled filtering processing, obtains the first time-domain signal；
IF process is carried out to first time-domain signal, obtains the second time-domain signal；
It is demodulated after carrying out channel filtering to second time-domain signal, obtains the frequency-region signal.
8. being obtained the method according to the description of claim 7 is characterized in that the frequency-region signal is passed to the second compensation circuit
To Nonlinear Transformation in Frequency Offset Estimation value, comprising:
Obtain symbolic integration/sampling unit output sampled value in second compensation circuit；
According to the sampled value, the DC component that second frequency-region signal includes is estimated；
The DC component is passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula to calculate；
Calculated result is subjected to loop filtering, obtains the Nonlinear Transformation in Frequency Offset Estimation value；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission speed
Rate, d are DC component.
9. a kind of compensation system of receiver carrier wave frequency deviation characterized by comprising
Third obtains module, for when receiving target packet, obtaining the payload data in the target packet；
Processing module obtains frequency-region signal for handling the payload；
Transfer module obtains Nonlinear Transformation in Frequency Offset Estimation value for the frequency-region signal to be passed to the second compensation circuit；
Second compensating module, for carrying out carrier wave frequency deviation benefit to the payload data according to the Nonlinear Transformation in Frequency Offset Estimation value
It repays.
10. system according to claim 9, which is characterized in that the transfer module includes:
Acquiring unit, for obtaining the symbolic integration in second compensation circuit/sampling unit output sampled value；
Estimation unit, for estimating the DC component that second frequency-region signal includes according to the sampled value；
Second computing unit is calculated for the DC component to be passed to preset Nonlinear Transformation in Frequency Offset Estimation expression formula；
Filter unit obtains the Nonlinear Transformation in Frequency Offset Estimation value for calculated result to be carried out loop filtering；
Wherein, the preset Nonlinear Transformation in Frequency Offset Estimation expression formula are as follows:Wherein, h is modulation index, and R is transmission speed
Rate, d are DC component.
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