CN209488618U - Adaptive equalizer in GFSK receiver - Google Patents
Adaptive equalizer in GFSK receiver Download PDFInfo
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- CN209488618U CN209488618U CN201821752506.8U CN201821752506U CN209488618U CN 209488618 U CN209488618 U CN 209488618U CN 201821752506 U CN201821752506 U CN 201821752506U CN 209488618 U CN209488618 U CN 209488618U
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Abstract
The utility model relates to the adaptive equalizers in a kind of GFSK receiver, comprising: the first balance module is filtered input signal, and to obtain the first filtering signal, first balance module works in 4 times of character rates；Second balance module, is filtered output signal, and to obtain the second filtering signal, second balance module works in 1 times of character rate；Adder carries out add operation to first filtering signal and second filtering signal, exports summing signal；The judging module makes decisions processing to the summing signal, obtains output signal；Error generation module exports first error signal and the second error signal；First tap coefficient configuration module, the second tap coefficient configuration module, for generating tap coefficient.Adaptive equalizer described in the utility model can be with intersymbol interference present in cancellation receiver, to improve the demodulation performance of receiver.
Description
Technical field
The utility model relates to the adaptive equalizers in field of communication technology more particularly to a kind of GFSK receiver.
Background technique
In digital communication systems, intersymbol interference (ISI, Intersymbol Interference), or be intersymbol string
It disturbs, intersymbol interference etc., is that there are influence communication performance in channel when multipath transmisstion.When introducing code in receiver
Between interfere after, the demodulation of receiver mistake will occur because of the presence of intersymbol interference.
Therefore, it is badly in need of proposing a kind of new scheme now, with intersymbol interference present in cancellation receiver, is connect to improve
The demodulation performance of receipts machine.
Utility model content
Technical problem
In view of this, technical problem to be solved by the utility model is: intersymbol interference present in cancellation receiver, thus
Improve the demodulation performance of receiver
Solution
In order to solve the above-mentioned technical problem, an embodiment according to the present utility model provides in a kind of GFSK receiver
Adaptive equalizer, the adaptive equalizer includes:
First balance module is electrically connected to the first tap coefficient configuration module, for receiving input signal and described first
The first tap coefficient or the second tap coefficient that tap coefficient configuration module transmits, and according to first tap coefficient or second
Tap coefficient is filtered input signal, to obtain the first filtering signal, wherein first balance module works in
4 times of character rates；
Second balance module is electrically connected to judging module and the second tap coefficient configuration module, for receiving described second
Third tap coefficient or the 4th tap coefficient that tap coefficient configuration module transmits and the output signal that the judging module transmits,
And the output signal is filtered according to the third tap coefficient or the 4th tap coefficient, to obtain second
Filtering signal, wherein second balance module works in 1 times of character rate；
Adder is electrically connected to first balance module and second balance module, for receiving first filter
Wave signal and second filtering signal carry out add operation to first filtering signal and second filtering signal, defeated
Summing signal out；
The judging module is electrically connected to the adder, for making decisions processing to the summing signal, obtains defeated
Signal out；
Error generation module is electrically connected to the adder, the judging module, transmits for receiving the adder
The output signal that summing signal and the judging module transmit, according to the summing signal, output signal output first error letter
Number and the second error signal；
First tap coefficient configuration module is electrically connected to the error generation module, for being believed according to the first error
Number output first tap coefficient exports second tap coefficient according to second error signal；
Second tap coefficient configuration module is electrically connected to the error generation module, for being believed according to the first error
Number output third tap coefficient exports the 4th tap coefficient according to second error signal.
In a kind of possible embodiment, first balance module obtains the first filtering letter according to the following formula
Number:
FFE_out (n)=X (n) * ffe_coeff (n), wherein X (n) includes the delay of the input signal at current n moment
The postpones signal of signal and multiple input signals before the current n moment, ffe_coeff (n) are first tap at current n moment
Coefficient or the second tap coefficient, first filtering signal at FFE_out (n) current n moment.
In a kind of possible embodiment, the first tap coefficient configuration module obtains described the by following formula
One tap coefficient or the second tap coefficient:
Ffe_coeff (n)=ffe_coeff (n-1)+delta × e_k (n) × x (n), wherein ffe_coeff (n-1)
For first tap coefficient or the second tap coefficient at n-1 moment, delta is error constant, and e_k (n) is first error letter
Number or second error signal, x (n) be the current n moment input signal.
In a kind of possible embodiment, second balance module obtains the second filtering letter according to the following formula
Number:
FBE_out (n)=D (n-1) * fbe_coef (n),
Wherein, D (n-1) is the postpones signal of multiple output signals of the judging module before the current n moment, fbe_
Coef (n) is the third tap coefficient or the 4th tap coefficient at current n moment, second filtering at FBE_out (n) current n moment
Signal.
In a kind of possible embodiment, the second tap coefficient configuration module obtains described according to the following formula
Three tap coefficients or the 4th tap coefficient:
Fbe_coeff (n)=fbe_coeff (n-1)+delta × e_k (n) × dec_out (n), wherein fbe_coeff
It (n-1) is the third tap coefficient or the 4th tap coefficient at n-1 moment, delta is error constant, and e_k (n) is first mistake
Difference signal or second error signal, dec_out (n) are output signal of the judging module at the current n moment.
In a kind of possible embodiment, the error generation module includes:
Enabled submodule, determines error signal producing method for receiving enable signal, and according to enable signal；And/or
Computational submodule is electrically connected to the enabled submodule, for being started counting after receiving counting instruction, and according to
The relationship of count value and count value threshold value determines error signal producing method.
In a kind of possible embodiment, it is less than institute in the enable signal for the first enable signal or the count value
When stating count value threshold value, the error generation module obtains the first error signal according to the following formula:
E_k1 (n)=R × (dec_out (n)-EQ_out (n)), wherein e_k1 (n) is the first error at current n moment
Signal, R are constant, and EQ_out (n) is the summing signal at current n moment, and dec_out (n) is the output signal at current n moment；
When the enable signal is the second enable signal or the count value is greater than or equal to the count value threshold value, institute
It states error generation module and obtains second error signal according to the following formula:
E_k2 (n)=dec_out (n)-EQ_out (n), wherein e_k2 (n) is second error signal at current n moment.
In a kind of possible embodiment, the judging module obtains the output signal by following formula:
Dec_out (n)=sign (EQ_out (n)), wherein dec_out (n) is the output signal at current n moment, EQ_
Out (n) is the summing signal at current n moment.
In a kind of possible embodiment, first balance module, second balance module are respectively ffe_N rank
FFE balanced device, fbe_N rank FBE balanced device, wherein ffe_N is integer greater than 1, and fbe_N is the integer greater than 1.
In a kind of possible embodiment, first balance module, second balance module respectively includes FIR has
Limit one of impact response filter, transversal filter, transposed form filter.
Other side according to the present utility model proposes a kind of application of the adaptive equalizer in GFSK receiver
Method, which comprises
Input signal and the first tap coefficient or the second tap coefficient are received with 4 times of character rates, and according to described first
Tap coefficient or the second tap coefficient are filtered input signal, to obtain the first filtering signal；
Third tap coefficient or the 4th tap coefficient and output signal are received with 1 times of character rate, and according to the third
Tap coefficient or the 4th tap coefficient are filtered the output signal, to obtain the second filtering signal；
Add operation is carried out to first filtering signal and second filtering signal, exports summing signal；
Processing is made decisions to the summing signal, obtains output signal；
According to the summing signal, output signal output first error signal and the second error signal；
First tap coefficient is exported according to the first error signal or institute is exported according to second error signal
State the second tap coefficient；
The third tap coefficient is exported according to the first error signal or institute is exported according to second error signal
State the 4th tap coefficient.
Beneficial effect
According to the adaptive equalizer of the above GFSK receiver, the utility model is balanced by the first balance module and second
Module can eliminate the intersymbol interference in channel, overcome the multipath effect of channel, improve the demodulation performance of GFSK receiver,
Also, by setting, the first balance module works in 4 times of character rates, the second balance module works under 1 times of character rate, makes
The utility model proposes the timing error tolerance of adaptive equalizer greatly improve.
According to below with reference to the accompanying drawings to detailed description of illustrative embodiments, the other feature and aspect of the utility model will
It becomes apparent.
Detailed description of the invention
Comprising in the description and constitute the attached drawing of part of specification and specification to together illustrate this practical new
Exemplary embodiment, feature and the aspect of type, and for explaining the principles of the present invention.
Fig. 1 shows the block diagram of the adaptive equalizer in the GFSK receiver according to one embodiment of the utility model.
Fig. 2 shows the block diagrams according to the adaptive equalizer of the GFSK receiver of the utility model one embodiment.
Fig. 3 shows the application side of the adaptive equalizer in the GFSK receiver according to one embodiment of the utility model
The flow chart of method.
Specific embodiment
The various exemplary embodiments, feature and aspect of the utility model are described in detail below with reference to attached drawing.In attached drawing
Identical appended drawing reference indicates element functionally identical or similar.Although the various aspects of embodiment are shown in the attached drawings,
It is unless otherwise indicated, it is not necessary to attached drawing drawn to scale.
Dedicated word " exemplary " means " being used as example, embodiment or illustrative " herein.Here as " exemplary "
Illustrated any embodiment should not necessarily be construed as preferred or advantageous over other embodiments.
In addition, in order to better illustrate the utility model, given in specific embodiment below numerous specific
Details.It will be appreciated by those skilled in the art that without certain details, the utility model equally be can be implemented.In some realities
In example, method well known to those skilled in the art, means, element and circuit are not described in detail, in order to highlight this reality
With novel purport.
It is generally included using the communication system of GFSK (Gauss Frequency Shift Keying, GFSK Gaussian Frequency Shift Keying)
GFSK transmitter, GFSK receiver, GFSK transmitter can be used as modulated terminal and be modulated to transmitting signal, and after sending modulation
Signal, GFSK receiver can be used for receiving GFSK transmitter transmitting signal and demodulated to obtain original signal.
GFSK transmitter includes Gauss formed filter, it can introduce intersymbol interference, and the presence meeting of intersymbol interference is so that GFSK receiver
There is error in demodulating received signal, to influence the demodulation performance of GFSK receiver.
To solve the problems, such as the intersymbol interference in GFSK receiver, the utility model proposes in a kind of GFSK receiver from
Adaptive equalizer.
Referring to Fig. 1, Fig. 1 shows the adaptive equalization in the GFSK receiver according to one embodiment of the utility model
The block diagram of device.
As shown in Figure 1, the adaptive equalizer includes:
First balance module 10 is electrically connected to the first tap coefficient configuration module 11, for receiving input signal and described
First tap coefficient configures the first tap coefficient or the second tap coefficient that 11 modules transmit, and according to first tap coefficient
Or second tap coefficient input signal is filtered, to obtain the first filtering signal, wherein first balance module
Work in 4 times of character rates.
Second balance module 12 is electrically connected to judging module 14 and the second tap coefficient configuration module 12, for receiving
It states third tap coefficient or the 4th tap coefficient that the second tap coefficient configuration module 12 transmits and the judging module 14 transmits
Output signal, and place is filtered to the output signal according to the third tap coefficient or the 4th tap coefficient
Reason, to obtain the second filtering signal, wherein second balance module works in 1 times of character rate.
Adder 16 is electrically connected to first balance module 10 and second balance module 12, described for receiving
First filtering signal and second filtering signal carry out addition fortune to first filtering signal and second filtering signal
It calculates, exports summing signal.
The judging module 14 is electrically connected to the adder 16, for making decisions processing to the summing signal, obtains
Take output signal.
Error generation module 15 is electrically connected to the adder 16, the judging module 14, for receiving the adder
The output signal that 16 summing signals transmitted and the judging module 14 transmit is exported according to the summing signal, output signal
First error signal and the second error signal.
First tap coefficient configuration module 11 is electrically connected to the error generation module 15, for missing according to described first
Difference signal exports first tap coefficient or exports second tap coefficient according to second error signal.
Second tap coefficient configuration module 13 is electrically connected to the error generation module 15, for missing according to described first
Difference signal exports the third tap coefficient or exports the 4th tap coefficient according to second error signal.
According to the adaptive equalizer of the above GFSK receiver, the utility model is balanced by the first balance module and second
Module can eliminate the intersymbol interference in channel, overcome the multipath effect of channel, improve the demodulation performance of GFSK receiver,
Also, by setting, the first balance module works in 4 times of character rates, the second balance module works under 1 times of character rate, makes
The utility model proposes the timing error tolerance of adaptive equalizer greatly improve.
For the first balance module 10:
In a kind of possible embodiment, input signal can be the received baseband sampling signal of GFSK receiver and pass through
After low-pass filter is inhibited out-of-band interference and noise, symbol synchronization is completed by frequency discriminator operation, and by sign synchronization
And removal DC component, then obtained letter after removing after the letter after DC component from initial sampling rate reduction of speed to character rate
Number.
In a kind of possible embodiment, the first balance module 10 can be FFE (the Feed Forward of ffe_N rank
Equalization, feed-forward are balanced) balanced device, wherein, ffe_N is the integer greater than 1.
In a kind of possible embodiment, first balance module 10 may include FIR finite impulse response filtering
One of device, transversal filter, transposed form filter.
In a kind of possible embodiment, first balance module 10 obtains first filtering according to the following formula
Signal:
FFE_out (n)=X (n) * ffe_coeff (n), wherein X (n) includes the delay of the input signal at current n moment
The postpones signal of signal and multiple input signals before the current n moment, ffe_coeff (n) are first tap at current n moment
Coefficient or the second tap coefficient, first filtering signal at FFE_out (n) current n moment, wherein symbol " * " is convolution symbol.
In the present embodiment, X (n) can store in the register of the first balance module 10, input signal successively by
It moves into register and stores, such as when the input signal x (n-1) at n-1 moment arrives, input signal x (n-1) is moved into and is deposited
It is stored in device, when the input signal x (n) at n moment arrives, input signal x (n) is moved into register and is stored, when the n+1 moment
Input signal x (n+1) arrive when, will input signal x (n+1) move into register in store.
When the first balance module 10 works in 4 times of character rates, the data in input signal are entered with 4 times of character rates
First balance module 10 passes through setting first for example, there is 4 data to enter the first balance module 10 in a symbol period
Balance module 10 works in 4 times of character rates, and the tolerance of the timing error of adaptive equalizer described in the utility model will
It is greatly improved.
First balance module 10 can in channel because caused by multipath transmisstion forward direction intersymbol interference be purged, can be with
Other interference signals are purged.
For the second balance module 12:
In a kind of possible embodiment, the second balance module 12 can be the feedback equalizer (Feed of fbe_N rank
Backward Eguaizer, FBE), wherein fbe_N is the integer greater than 1.
In a kind of possible embodiment, the second balance module 12 may include FIR finite impulse response filter, cross
To one of filter, transposed form filter.
In a kind of possible embodiment, the second balance module 12 obtains the second filtering letter according to the following formula
Number:
FBE_out (n)=D (n-1) * fbe_coef (n), wherein D (n-1) is the judging module at the current n moment
The postpones signal of multiple output signals before, fbe_coef (n) are third tap coefficient or the 4th tap system at current n moment
Number, second filtering signal at FBE_out (n) current n moment.
D (n-1) can store in judging module 14, D (n-1) include n-1 moment, n-2 moment, n-3 moment etc. it is multiple
The output signal d (n-1) at moment, d (n-2), d (n-3) etc..
When the second balance module 12 works in 1 times of character rate, adaptive equalizer described in the utility model is determined
When error tolerance will be greatly improved.
First balance module 12 can in channel because intersymbol interference backward caused by multipath transmisstion is purged, can be with
Other interference signals are purged.
In a kind of possible embodiment, in the first balance module 10 and the second balance module 12, the first tap coefficient
Can be corresponding with third tap coefficient, when the first balance module 10 is filtered input signal according to the first tap coefficient
When generating the first filtering signal, the second balance module 12 can according to third tap coefficient to the output signal of judging module 14 into
Row filtering processing, to generate the second filtering signal.
In a kind of possible embodiment, in the first balance module 10 and the second balance module 12, the second tap coefficient
Can be corresponding with the 4th tap coefficient, when the first balance module 10 is filtered input signal according to the second tap coefficient
When generating the first filtering signal, the second balance module 12 can according to the 4th tap coefficient to the output signal of judging module 14 into
Row filtering processing, to generate the second filtering signal.
For adder 16:
In a kind of possible embodiment, adder 16 by following formula export summing signal, EQ_out (n)=
FFE_out (n)+FBE_out (n), wherein EQ_out (n) is the summing signal at current n moment.
In a kind of possible embodiment, the first balance module 10 is worked with 4 times of character rates, the second balance module 12
It is worked with 1 times of character rate, for example, the first balance module 10 is obtaining n/ in synchronization n (such as a symbol period)
4,2n/4,3n/4 and n moment respectively export 1 filtering signal, and the filtering signal that the n moment can be exported is as the first filtering letter
Number；At the n moment, the second balance module 12 exports the second filtering signal, and adder 16 is by first filtering signal and described the
Two filtering signals are added, and obtain summing signal.
For judging module 14:
In a kind of possible embodiment, judging module 14 may include the component for keeping in the postpones signal
Or device, such as delay line (not shown).
In a kind of possible embodiment, judging module 14 obtains the output signal by following formula:
Dec_out (n)=sign (EQ_out (n)), wherein dec_out (n) is the output signal at current n moment.
For error generation module 15:
Referring to Fig. 2, Fig. 2 shows the adaptive equalizers according to the GFSK receiver of the utility model one embodiment
Block diagram.
As shown in Fig. 2, in a kind of possible embodiment, error generation module 15 may include:
Enabled submodule 151, determines error signal producing method for receiving enable signal, and according to enable signal；With/
Or
Computational submodule 153 is electrically connected to the enabled submodule 151, for being started counting after receiving counting instruction,
And error signal producing method is determined according to the relationship of count value and count value threshold value.
In a kind of possible embodiment, when the enable signal that enabled submodule 151 receives is first enabled
When the count value that signal or computational submodule 153 count is less than the count value threshold value, the error generation module according to
Following formula obtains the first error signal:
E_k1 (n)=R × (dec_out (n)-EQ_out (n)), wherein e_k1 (n) is the first error at current n moment
Signal, R are constant, and EQ_out (n) is the summing signal at current n moment, and dec_out (n) is the output signal at current n moment.
In a kind of possible embodiment, the enable signal be the second enable signal or the count value be greater than or
When equal to the count value threshold value, the error generation module obtains second error signal according to the following formula:
E_k2 (n)=dec_out (n)-EQ_out (n), wherein e_k2 (n) is second error signal at current n moment.
In a kind of possible embodiment, constant R can be obtained by following formula:
R=E { x (n) ^2 }/E | x (n) | }, wherein E is the symbol of averaged.
In some specific embodiments, when input signal is 2-GFSK mode, R can be 1；When input signal is
When 4-GFSK mode, R can be 2.5.
In a kind of possible embodiment, the first enable signal can be low level signal, and the second enable signal can be with
For high level signal, the count value of computational submodule 153 can be the appearance number of symbol period, and count value threshold value can be symbol
Number number of cycles threshold value.
In a kind of possible embodiment, the enabled letter of the available enabled acquisition of submodule 151 of computational submodule 153
Number, using enable signal as instruction is counted, according to the number of the state computation symbol period of enable signal and as described
Count value, for example, when being enable signal is high level signal, it is believed that enable signal is useful signal, at this point, calculating son
Module 153 can start to count symbol period, when count value is less than count value threshold value, obtain first error signal,
(such as enable signal is invalid or count value is greater than count value threshold value etc.) obtains the second error signal in other cases.Calculate son
Module 153 can also start to calculate the number of symbol period and as institute after adaptive equalizer receives input signal
Count value is stated, it is of course also possible to receive externally input other command signal and command signal starts to calculate based on the received
The number of symbol period and as count value.
After enabled submodule 53 obtains the second enable signal, error generation module 15 can obtain the according to above formula
Two error signals.
As previously mentioned, enabled submodule 151 and computational submodule 153 can determine error signal respectively, it can also be simultaneously
Determine error signal, for example, when enable signal is effective (such as enable signal is the second enable signal), and count value is less than meter
When numerical threshold, error generation module 15 generates first error signal, and in other cases, error generation module 15 generates second
Error signal.
When error generation module 15 generate first error signal when, GFSK receiver described in the utility model it is adaptive
Balanced device works in the blind equalization mode of local Constant Modulus Algorithm (Constant Modulus Algorithm, CMA), works as error
When generation module 15 generates the second error signal, adaptive equalizer is worked in based on lowest mean square root algorithm ((Least Mean
Squares, LMS) towards decision pattern.
For the first tap coefficient configuration module 11:
In a kind of possible embodiment, the first tap coefficient configuration module 11 can be obtained by following formula
First tap coefficient or the second tap coefficient:
Ffe_coeff (n)=ffe_coeff (n-1)+delta × e_k (n) × x (n), wherein ffe_coeff (n-1)
For first tap coefficient or the second tap coefficient at n-1 moment, delta is error constant, and e_k (n) is first error letter
Number or second error signal, x (n) be the current n moment input signal.
In the present embodiment, the first tap coefficient configuration module 11 can obtain the first tap by first error signal
Coefficient obtains the second tap coefficient by the second error signal.
In a kind of possible embodiment, delta can decimal between 0-1, for example, delta can be 0.01.
In a kind of possible embodiment, the first tap coefficient configuration module 11, can after generating the second tap coefficient
To cover the first tap coefficient.
For the second tap coefficient configuration module 13:
In a kind of possible embodiment, the second tap coefficient configuration module 13 can obtain according to the following formula
The third tap coefficient or the 4th tap coefficient:
Fbe_coeff (n)=fbe_coeff (n-1)+delta × e_k (n) × dec_out (n), wherein fbe_coeff
It (n-1) is the third tap coefficient or the 4th tap coefficient at n-1 moment, delta is error constant, and e_k (n) is first mistake
Difference signal or second error signal, dec_out (n) are output signal of the judging module at the current n moment.
In the present embodiment, the second tap coefficient configuration module 13 obtains third tap system by first error signal
Number obtains the 4th tap coefficient by the second error signal.
It, can be in advance to the first tap coefficient configuration module 11 and the second tap coefficient in a kind of possible embodiment
Configuration module 13 is initialized, to deposit in the first tap coefficient configuration module 11 and the second tap coefficient configuration module 13
Storage initialization tap coefficient can be by being stored in the configuration of the first tap coefficient when adaptive equalizer is started to work
Initialization tap coefficient in module 11 and the second tap coefficient configuration module 13 works, and hereafter, the first tap coefficient is matched
It sets module 11 and the second tap coefficient configuration module 13 and respective tap coefficient is updated by mode above-mentioned.
In a kind of possible embodiment, the second tap coefficient configuration module 13, can after generating the 4th tap coefficient
To cover third tap coefficient.
It should be noted that the descriptions such as above " first ", " second " and are not had to clearly introduce the utility model
In limitation the utility model.
Referring to Fig. 3, Fig. 3 shows the adaptive equalization in the GFSK receiver according to one embodiment of the utility model
The flow chart of the application method of device.
As shown in Figure 3, which comprises
Step S110, with 4 times of character rates reception input signals and the first tap coefficient or the second tap coefficient, and according to
First tap coefficient or the second tap coefficient are filtered input signal, to obtain the first filtering signal；
Step S120, with 1 times of character rate reception third tap coefficient or the 4th tap coefficient and output signal, and according to
The third tap coefficient or the 4th tap coefficient are filtered the output signal, to obtain the second filtering letter
Number；
Step S130 carries out add operation, output summation letter to first filtering signal and second filtering signal
Number；
Step S140 makes decisions processing to the summing signal, obtains output signal；
Step S150, according to the summing signal, output signal output first error signal and the second error signal；
Step S160 exports first tap coefficient according to the first error signal or is believed according to second error
Number output second tap coefficient；
Step S170 exports the third tap coefficient according to the first error signal or is believed according to second error
Number output the 4th tap coefficient.
Above description is only a specific implementation of the present invention, but the protection scope of the utility model is not limited to
In this, anyone skilled in the art within the technical scope disclosed by the utility model, can readily occur in variation
Or replacement, it should be covered within the scope of the utility model.Therefore, the protection scope of the utility model should be with the power
Subject to the protection scope that benefit requires.
Claims (10)
1. the adaptive equalizer in a kind of GFSK receiver, which is characterized in that the adaptive equalizer includes:
First balance module is electrically connected to the first tap coefficient configuration module, for receiving input signal and first tap
The first tap coefficient or the second tap coefficient that coefficient configuration module transmits, and according to first tap coefficient or the second tap
Coefficient is filtered input signal, to obtain the first filtering signal, wherein first balance module works in 4 times
Character rate；
Second balance module is electrically connected to judging module and the second tap coefficient configuration module, for receiving second tap
Third tap coefficient or the 4th tap coefficient that coefficient configuration module transmits and the output signal that the judging module transmits, and root
The output signal is filtered according to the third tap coefficient or the 4th tap coefficient, to obtain the second filtering
Signal, wherein second balance module works in 1 times of character rate；
Adder is electrically connected to first balance module and second balance module, for receiving the first filtering letter
Number and second filtering signal, add operation is carried out to first filtering signal and second filtering signal, output is asked
And signal；
The judging module is electrically connected to the adder, for making decisions processing to the summing signal, obtains output letter
Number；
Error generation module, is electrically connected to the adder, the judging module, the summation transmitted for receiving the adder
The output signal that signal and the judging module transmit, according to the summing signal, output signal output first error signal and
Second error signal；
First tap coefficient configuration module is electrically connected to the error generation module, for defeated according to the first error signal
First tap coefficient or second tap coefficient is exported according to second error signal out；
Second tap coefficient configuration module is electrically connected to the error generation module, for defeated according to the first error signal
The third tap coefficient or the 4th tap coefficient is exported according to second error signal out.
2. adaptive equalizer according to claim 1, which is characterized in that first balance module is according to the following formula
Obtain first filtering signal:
FFE_out (n)=X (n) * ffe_coeff (n), wherein X (n) includes the postpones signal of the input signal at current n moment
And the postpones signal of multiple input signals before the current n moment, ffe_coeff (n) are first tap coefficient at current n moment
Or second tap coefficient, first filtering signal at FFE_out (n) current n moment.
3. adaptive equalizer according to claim 2, which is characterized in that the first tap coefficient configuration module passes through
Following formula obtains first tap coefficient or the second tap coefficient:
Ffe_coeff (n)=ffe_coeff (n-1)+delta × e_k (n) × x (n), wherein ffe_coeff (n-1) is n-1
First tap coefficient or the second tap coefficient at moment, delta are error constant, and e_k (n) is the first error signal or institute
The second error signal is stated, x (n) is the input signal at current n moment.
4. adaptive equalizer according to claim 1, which is characterized in that second balance module is according to the following formula
Obtain second filtering signal:
FBE_out (n)=D (n-1) * fbe_coef (n),
Wherein, D (n-1) is the postpones signal of multiple output signals of the judging module before the current n moment, fbe_coef
It (n) is the third tap coefficient or the 4th tap coefficient at current n moment, second filtering signal at FBE_out (n) current n moment.
5. adaptive equalizer according to claim 4, which is characterized in that the second tap coefficient configuration module according to
Following formula obtains the third tap coefficient or the 4th tap coefficient:
Fbe_coeff (n)=fbe_coeff (n-1)+delta × e_k (n) × dec_out (n), wherein fbe_coeff (n-
It 1) is the third tap coefficient or the 4th tap coefficient at n-1 moment, delta is error constant, and e_k (n) is the first error
Signal or second error signal, dec_out (n) are output signal of the judging module at the current n moment.
6. adaptive equalizer according to claim 1, which is characterized in that the error generation module includes:
Enabled submodule, determines error signal producing method for receiving enable signal, and according to enable signal；And/or
Computational submodule is electrically connected to the enabled submodule, for starting counting after receiving counting instruction, and according to counting
The relationship of value and count value threshold value determines error signal producing method.
7. adaptive equalizer according to claim 6, which is characterized in that
When the enable signal is the first enable signal or the count value is less than the count value threshold value, the error is generated
Module obtains the first error signal according to the following formula:
E_k1 (n)=R × (dec_out (n)-EQ_out (n)), wherein e_k1 (n) is the first error signal at current n moment,
R is constant, and EQ_out (n) is the summing signal at current n moment, and dec_out (n) is the output signal at current n moment；
When the enable signal is the second enable signal or the count value is greater than or equal to the count value threshold value, the mistake
Poor generation module obtains second error signal according to the following formula:
E_k2 (n)=dec_out (n)-EQ_out (n), wherein e_k2 (n) is second error signal at current n moment.
8. adaptive equalizer according to claim 1, which is characterized in that the judging module is obtained by following formula
The output signal:
Dec_out (n)=sign (EQ_out (n)), wherein dec_out (n) is the output signal at current n moment, EQ_out
It (n) is the summing signal at current n moment.
9. adaptive equalizer according to claim 1, which is characterized in that first balance module, described second are
Weighing apparatus module is respectively the FBE balanced device of the FFE balanced device of ffe_N rank, fbe_N rank, wherein and ffe_N is the integer greater than 1,
Fbe_N is the integer greater than 1.
10. adaptive equalizer according to claim 1, which is characterized in that first balance module, described second are
Weighing apparatus module respectively includes one of FIR finite impulse response filter, transversal filter, transposed form filter.
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| CN111107025A (en) * | 2018-10-26 | 2020-05-05 | 上海晟矽微电子股份有限公司 | Adaptive equalizer in GFSK receiver |
| CN113541733A (en) * | 2021-09-17 | 2021-10-22 | 北京国科天迅科技有限公司 | Equalization and echo cancellation device, method, computer device and storage medium |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111107025A (en) * | 2018-10-26 | 2020-05-05 | 上海晟矽微电子股份有限公司 | Adaptive equalizer in GFSK receiver |
| CN113541733A (en) * | 2021-09-17 | 2021-10-22 | 北京国科天迅科技有限公司 | Equalization and echo cancellation device, method, computer device and storage medium |
| CN113541733B (en) * | 2021-09-17 | 2022-01-28 | 北京国科天迅科技有限公司 | Equalization and echo cancellation device, method, computer device and storage medium |
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