CN103457670B - The method and apparatus sending data and the method and apparatus recovering initial data - Google Patents

Abstract

Disclose the method and apparatus recovering data a kind of method and apparatus sending data and the digital signal after receiving.The method of described transmission data includes: described data are carried out second differnce coding；And use the data-modulated carrier after second differnce coding, to send this modulation data.By said method and equipment, in transmitters data to be sent can be carried out second differnce coding, and the most correspondingly carry out second differnce decoding.Due to the character of second differnce coding itself, even if carrying out in receivers creating frequency difference and the ambiguous solution differed during carrier auxiliary, thus cause carrier auxiliary mistake, it is also possible to prevent the correct recovery of these carrier auxiliary erroneous effects data.

Description

The method and apparatus sending data and the method and apparatus recovering initial data

Technical field

The present invention relates to optical communication field, and be specifically related to a kind of method sending data in transmitters With equipment and in receivers digital signal after receiving recover the original number that sends in transmitters According to method and apparatus.

Background technology

Development along with optical communication technique, it is proposed that coherent light communication.Coherent light communication has frequency and selects Good, the spectrum efficiency advantages of higher of property, thus message capacity can be improved.Additionally, in coherent light communication, Dispersion and polarization mode dispersion are all linear damage to the damage of signal, and now communication channel can be modeled as linearly Time-invariant system, just can compensate linear damage by Digital Signal Processing (DSP) technology that appropriateness is complicated Wound.Therefore, coherent optical communication system is becoming study hotspot.

Along with the progress of electronic technology, the cost of Digital Signal Processing is greatly lowered.The coherent light of a new generation Communication system generally introduces DSP technology.In coherent optical communication receiver, using intrinsic light carrier solution After adjusting flashlight, analog-digital converter (ADC) is used the obtained signal of telecommunication to be sampled, then to sampled signal Carry out Digital Signal Processing.This Digital Signal Processing generally includes: dispersion compensation → clock recovery → adaptive Should filter (carrying out polarization demultiplexing and polarization mode dispersion (PMD) compensation) → carrier auxiliary (carry out frequency difference estimation with Compensate) → carrier auxiliary (carrying out phase noise estimate and compensate) → bit decision → decoding.

In current coherent optical communication receiver, after signal has been carried out adaptive-filtering, the completeest Having become residual chromatic dispersion compensation and polarization demultiplexing, thus obtained data is the modulation produced in transmitters Data and the frequency difference factor and to differ the factor long-pending, the described frequency difference factor is by the transmission laser instrument in transmitter And the frequency difference decision between the local laser instrument in receiver, the described difference factor is to be swashed by described transmission Initial phase difference between light device and local laser instrument and phase noise determine.Specifically, it is assumed that The modulation system used in transmitter is M-PSK modulation, the most in receivers, is carrying out self adaptation filter The signal obtained after ripple is represented by:

$E_i=\exp \left(j2\mathrm{\π}\frac{X_i}{M}\right)\exp (j2\mathrm{\πi\ΔfT}+\mathrm{\θ})---\left(1\right)$

Wherein M is order of modulation, X_iFor the i-th data (code element) (i is positive integer) in described modulation data, X_i=0,1 ..., M-1, T are code-element period, and T=1/b, b are the chip rate of modulation data, and Δ f is institute Stating frequency difference, θ is described difference.In order to determine described modulation data X_i, need to calculate frequency difference Δ f and difference θ, and calculating thereafter eliminate (that is, compensating) described frequency difference and difference.

Have been proposed for the multiple estimation and compensate frequency difference and the method for difference, such as when carrying out carrier auxiliary Training sequence method and blind estimate method.Training sequence method uses known training sequence to determine frequency difference and difference. For frequency difference, if the element position determined in training sequence, the modulation data produced the most in transmitters X_iIt is known, thus can eliminate the item relevant with these modulation data from above formula (1), then with disappearing Two signal E of continuous print except described item_i+1And E_iIt is divided by, can obtain

$[E_{i+1}\×\exp (-j\×\frac{X_{i+1}}{M}\×2\mathrm{\π})]\÷[E_i\×\exp (-j\×\frac{X_i}{M}\×2\mathrm{\π})]=\exp (j2\mathrm{\π\ΔfT}+{\mathrm{\θ}}_{i+1}-{\mathrm{\θ}}_i)---\left(2\right)\·$

Because

exp(j2πΔfT)=exp[j(2πΔfT+N×2π)] (3)

So Δ f and Δ f+N_fB is the solution of formula (2), wherein N_fFor integer, i.e. the frequency difference Δ f calculated deposits Can not be uniquely identified at ambiguous solution.When carrying out frequency difference and compensating, can be by E_iIt is multiplied by exp(-j2πiΔfT).Due to exp (-j2 π i Δ fT)=exp [-j2 π i (Δ f+N_fB) T], therefore, using training sequence The ambiguous solution of the frequency difference produced in the case of row does not interferes with the correct recovery of data.But, due to needs Sending training sequence and determine frequency difference, therefore training sequence method significantly reduces effective data transfer rate, And need first to find data frame head by the method synchronized, cause the complexity of communication system to increase.

Blind estimate method need not use previously known data.The most commonly used blind estimate method is M time Take advantage of method.Specifically, for frequency difference, owing to modulation data Xi meet

${\left[\exp \left(j2\mathrm{\π}\frac{X_i}{M}\right)\right]}^M=\exp \left(j2\mathrm{\π}{X}_i\right)=1---\left(4\right)$

Therefore modulation data X can be eliminated by above formula (1) being carried out M power_i.I.e., it is possible to calculate Two signal E of continuous print_i+1And E_iM power and be divided by:

E^M _i+1/E^M _i=exp(j2πMΔfT) (5)

Now, Δ f and Δ f+N_fB/M is the solution of formula (5), wherein N_fFor integer, i.e. frequency difference Δ f there is also Ambiguous solution and can not be uniquely identified.When carrying out frequency difference and compensating, can be by E_iIt is multiplied by exp (-j2 π i Δ fT). Now, if N_fNot the integral multiple of M, then exp (-j2 π i Δ fT) ≠ exp [-j2 π i (Δ f+N_fB/M) T], Cause using Δ f and Δ f+N_fB/M carries out frequency difference and compensates and will produce different compensation results, i.e. if do not had The correct solution selecting frequency difference, follow-up data is had to recover to will appear from mistake.In order to solve this problem, In blind estimate method, generally make N_fIt is 0, and assumes that actual frequency difference existsIn the range of.This meaning The frequency difference that taste between needing transmitter and receiver controlsIn the range of.But, in phase In some application scenarios of dry optical communication system, but such as requiring low one-tenth to data rate requirement is the highest In this application scenarios (such as desert area), usually use low-cost laser.In these scenes, Chip rate is the lowest, generally below 2G.As a example by QPSK (M=4) modulation system, if using blind The estimation technique, then the frequency difference between needing transmitter and receiver controlsBetween.But, the frequency drift characteristic of low-cost laser is difficult to meet is somebody's turn to do Requirement.In this case, if the frequency difference between transmitter and receiver is positioned atScope outside, Δ f+N can be determined with training sequence_fN in b/M_fCorrect value, or N can be calculated simultaneously_fInstitute Possible value, then determines N according to related feedback information_fCorrect value, but this cannot tackle Frequency difference the Rapid Variable Design even situation of frequency shear.

For difference θ, in blind estimate method, can obtain with M multiplication of calculating formula (1):

(E_i)^M=exp (j2 π Mi Δ fT+M θ) (6)

Additionally, θ and θ+2 π N_θ/ M is the solution of formula (6), wherein N_θFor integer.That is, difference θ there is also Ambiguous solution and can not be uniquely identified.In this case, if difference to be defined as θ, and actual Difference be θ+2 π N_θ/ M, then modulation data X_i(X will be mistaken for_i+N_θ) Mod (M), cause subsequently Data recover mistake occur.

Accordingly, it would be desirable to a kind of method sending data in transmitters and recovering in receivers at transmitter The method of the data of middle transmission, in order to by suitably processing data to be sent in transmitter, prevent Receiver carries out the frequency difference of generation during carrier auxiliary and affects the correct of data recovery with the ambiguous solution differed Property.

Summary of the invention

It is an object of the present invention to provide a kind of method and apparatus sending data and the number after receiving Word signal recovers the method and apparatus of initial data, by described method and apparatus, and can be in transmitters Suitably process data to be sent, thus prevent from carrying out in receivers the frequency difference of generation during carrier auxiliary The correctness that data are recovered is affected with the ambiguous solution differed.

According to an aspect of the invention, it is provided a kind of method sending data, including: to described number According to carrying out second differnce coding；And use the data-modulated carrier after second differnce coding, it is somebody's turn to do to send Modulation data.

According to a further aspect in the invention, it is provided that a kind of digital signal after receiving recovers initial data Method, including: digital signal is carried out bit decision, with obtain judgement data；And sentence described Certainly data carry out second differnce decoding, thus recover initial data.

According to a further aspect in the invention, it is provided that a kind of equipment sending data, including: code device, It is configured to described data are carried out second differnce coding；Modulating device, is configured with second differnce Data-modulated carrier after coding, to send this modulation data.

According to a further aspect in the invention, it is provided that a kind of digital signal after receiving recovers initial data Equipment, including judgment device, be configured to digital signal is carried out bit decision, to obtain judgement Data；And decoding apparatus, it is configured to described judgement data are carried out second differnce decoding, thus extensive Multiple initial data.

By the method and apparatus according to the above-mentioned aspect of the present invention, can be in transmitters to number to be sent According to carrying out second differnce coding, and when carrying out carrier auxiliary in receivers, can correspondingly carry out Second differnce decodes.Due to the character of second differnce coding itself, even if it is extensive to carry out carrier wave in receivers Create frequency difference and the ambiguous solution differed time multiple, thus cause carrier auxiliary mistake, it is also possible to prevent this load Ripple recovers the erroneous effects correct recovery to the transmission data in transmitter, in other words, even if from described discrimination Justice solution have selected incorrect solution, also do not interfere with the correctness that the data carried out in receivers are recovered.

Accompanying drawing explanation

By combining accompanying drawing, embodiments of the present invention is described in detail, above and other mesh of the present invention , feature and advantage will become apparent, wherein:

Fig. 1 shows the flow chart of the method for transmission data according to embodiments of the present invention.

Fig. 2 shows that the digital signal after receiving according to embodiments of the present invention recovers the side of initial data The flow chart of method.

Fig. 3 shows the block diagram of the equipment of transmission data according to embodiments of the present invention.

Fig. 4 shows that the digital signal after receiving according to embodiments of the present invention recovers setting of initial data Standby block diagram.

Detailed description of the invention

Embodiments of the invention are described below with reference to accompanying drawings.It is understood that the embodiments described herein It is merely illustrative, and is not necessarily to be construed as limiting the scope of the present invention.

First, the method describing transmission data according to embodiments of the present invention with reference to Fig. 1.The method can To perform in the transmitter of optical communication system (such as coherent optical communication system).

As it is shown in figure 1, in step S101, the data of receiver to be sent to are carried out second differnce volume Code.Specifically, described data can first carry out first-order difference encode to produce inter-coded data, so After described inter-coded data can be carried out again first-order difference coding, with produce described second differnce compile Data after Ma.

More specifically, it is assumed that packet to be sent contains N_dataI+1 in individual code element, and described data With the i-th+2 data (that is, in the code element that i+1 code-element period and the i-th+2 code-element periods are to be sent) X respectively_i+1And X_i+2(i is positive integer), then can according to the following formula (7) and (8) to X_i+1And X_i+2 Carry out first-order difference coding, to produce data (that is, the inter-coded data) Y after first-order difference encodes_i+1 And Y_i+2:

Y_i+1=(Y_i+X_i+1) Mod (M) (7)

Y_i+2=(Y_i+1+X_i+2) Mod (M) (8)

Wherein, M is the order of modulation of the MPSK modulation carried out in transmitters, and M=2ⁿ, n is more than 1 Integer, Y_iIt is that the i-th data in described data are carried out the first-order difference that first-order difference coding produces Data (that is, inter-coded data) after coding, and Y₁=X₁。

It is then possible to according to the following formula (9) and (10), for described inter-coded data Y_i+1And Y_i+2 Again carry out first-order difference coding, to produce and X_i+1And X_i+2The corresponding data after second differnce coding Z_i+1And Z_i+2:

Z_i+1=(Z_i+Y_i+1) Mod (M) (9)

Z_i+2=(Z_i+1+Y_i+2) Mod (M) (10)

It follows that in step s 102, it is possible to use after the second differnce coding that step S101 produces Data modulated optical carrier, to send this modulation data.This modulation can be above-mentioned MPSK modulation.Example As, it is possible to use the laser instrument arranged in transmitters produces the light carrier of preset frequency, then uses two Data after jump Coded modulate this light carrier.It is this area owing to carrying out the concrete grammar of this modulation Known, the most here omit it and describe in detail.

By this modulation, the data after can described second differnce being encoded are loaded on optical signal.Then, Can be via optical fiber by the receiver of this optical signal to optical communication system.

Receiver receives this optical signal, and this optical signal is carried out opto-electronic conversion (that is, optical modulator) with It is converted into the signal of telecommunication, then this signal of telecommunication is included dispersion compensation, clock recovery, self adaptation The Digital Signal Processing of filtering, thus obtain the digital signal that can be represented by above formula (1).In receivers The concrete grammar carrying out above-mentioned opto-electronic conversion, dispersion compensation, clock recovery and adaptive-filtering is this area Known, and they are also not belonging to the inventive point of the present invention, that the most here omits them is detailed Describe.

After above-mentioned process, the digital signal shown in above formula (1) can be carried out frequency difference estimation and Compensate and difference is estimated and compensates.Can use the blind estimate method being described above to calculate frequency difference and Difference.As described above, for frequency difference, there is multiple solution Δ f and Δ f+N_fB/M, for difference, deposits At multiple solution θ and θ+2 π N_θ/M.In an embodiment of the present invention, a solution of frequency difference can arbitrarily be selected As estimated frequency difference, and can arbitrarily select a solution of difference as estimated difference.? Here, as an example it is supposed that at the plurality of solution Δ f and Δ f+N_fB/M select Δ f as estimated Frequency difference, and the frequency difference of reality is Δ f+N_fB/M, at the plurality of solution θ and θ+2 π N_θ/ M select θ make For estimated difference, and actual difference is θ+2 π N_θ/M.It is then possible to shown in above formula (1) Digital signal carries out frequency difference compensation and difference compensates.Specifically, can be by by the letter shown in above formula (1) Number it is multiplied by exp (-j2 π i Δ fT) to eliminate frequency difference, and is multiplied by exp (-θ) to eliminate difference.After this compensation Digital signal, i.e. carried out demodulation and through the M-PSK complex signal of Digital Signal Processing, can be extensive The multiple initial data sent in transmitters.

Below, describe the described digital signal after receiving according to the present invention with reference to Fig. 2 to recover sending out The method penetrating the initial data sent in machine.

As in figure 2 it is shown, in step s 201, described digital signal is carried out bit decision, sentence to obtain Certainly data.Method well known in the art can be used to carry out above-mentioned bit decision, here omit it detailed Thin description.Here, at selection Δ f as estimated frequency difference, and select θ as estimated phase Difference, and the frequency difference of reality is Δ f+N_fB/M, actual difference is θ+2 π N_θIn the case of/M, described judgement Data are represented by

Z'_i=[Z_i+i*N_f+N_θ]Mod(M) (11)

It follows that in step S202, described judgement data can be carried out second differnce decoding, thus Recover the initial data sent in transmitters.

Specifically, to the i-th+2 data Z in described judgement data '_i+2, (12) are to it according to the following formula Carry out second differnce decoding, to produce decoded data X '_i+2, as described initial data:

X'_i+2=(Z'_i+2-2Z'_i+1-Z'_i)Mod(M) (12)

Wherein, Z '_i+1And Z '_iBeing respectively i+1 the data in described judgement data and i-th data, i is just Integer.

Here, formula (7)-(11) are substituted into formula (12) can obtain:

$\begin{array}{c}{X^{\′}}_{i+2}=[{Z^{\′}}_{i+2}-2\×{Z^{\′}}_{i+1}+{Z^{\′}}_i]\mathrm{Mod}\left(M\right)\\ =\begin{array}{c}\left\{\begin{array}{c}{Z}_{i+2}+(i+2)\×N_f+N_{\mathrm{\θ}}-2\×[Z_{i+1}+(i+1)\×N_f+N_{\mathrm{\θ}}]\\ +Z_i+i\×N_f+N_{\mathrm{\θ}}\end{array}\right\}\mathrm{Mod}\left(M\right)\end{array}\\ =[Z_{i+2}-2\×Z_{i+1}+Z_i]\mathrm{Mod}\left(M\right)\\ =[Z_{i+2}-Z_{i+1}-Z_{i+1}+Z_i]\mathrm{Mod}\left(M\right)\\ =[Y_{i+2}-Y_{i+1}]\mathrm{Mod}\left(M\right)\\ =X_{i+2}\end{array}---\left(13\right)$

It will be seen that in above formula, N_fAnd N_θIt is eliminated.In other words, by carrying out above-mentioned second differnce Coding and decoding, in the case of there is multiple ambiguous solution, even if not having when estimating in frequency difference estimation and difference Have and select the correct solution estimated value as frequency difference and the estimated value of difference, thus cause carrier auxiliary the most just Really, it is also possible to the most correctly recover the initial data sent at transmitter.

Therefore, utilize the said method according to the present invention, even if existing when frequency difference estimation and difference are estimated Frequency difference and the ambiguous solution of difference, these ambiguous solutions do not interfere with the correctness that data are recovered yet.

The equipment of transmission data according to embodiments of the present invention is described next, with reference to Fig. 3.This equipment Can be installed in the transmitter of optical communication system, thus form a part for transmitter.

As it is shown on figure 3, transmitter 300 can include the equipment of transmission data according to embodiments of the present invention 301 and for producing the laser instrument 302 of light carrier of preset frequency.Send out it should be noted that, Fig. 3 merely illustrates Penetrate part directly related with embodiments of the invention in machine, and eliminate that be probably for transmitter must Want, but the part being not directly relevant to embodiments of the invention.

Data to be sent are processed by the equipment 301 of transmission data according to embodiments of the present invention.Tool Body ground, as it is shown on figure 3, described equipment 301 includes code device 3011 and modulating device 3012.? Here, the operation performed due to equipment 301 is essentially identical with the method being described above, therefore at this In omit the detailed description to same detail.

Code device 3011 carries out second differnce coding to data to be sent.Specifically, code device 3011 first can carry out first-order difference to described data encodes to produce inter-coded data, then can be right Described inter-coded data carries out first-order difference coding again, to produce the number after described second differnce encodes According to.

More specifically, it is assumed that packet to be sent contains N_dataI+1 in individual code element, and described data With the i-th+2 data (that is, in the code element that i+1 code-element period and the i-th+2 code-element periods are to be sent) X respectively_i+1And X_i+2(i is positive integer), then code device 3011 can be according to above formula (7) and (8) To X_i+1And X_i+2Carry out first-order difference coding, (that is, middle to produce the data after first-order difference encodes Coded data) Y_i+1And Y_i+2.Then, code device 3011 can according to above formula (9) and (10), For described inter-coded data Y_i+1And Y_i+2Again carry out first-order difference coding, to produce and X_i+1With X_i+2Corresponding data Z after second differnce coding_i+1And Z_i+2。

Modulating device 3012 can use the data after the second differnce coding of code device 3011 output Modulated optical carrier, to send this modulation data.Described modulation can be MPSK modulation, wherein M=2ⁿ, N is the integer more than 1.Specifically, modulating device 3012 can use and export from code device 3011 Second differnce coding after the light carrier of preset frequency of data modulation laser instrument 302 output, carry out This modulation.It is to it is known in the art that here to omit it detailed owing to carrying out the concrete grammar of this modulation Thin description.

By above-mentioned modulation, modulating device 3012 can produce the data after being loaded with second differnce coding Optical signal.Then, this optical signal can be sent to the receiver of optical communication system via optical fiber.

Below, with reference to Fig. 4 describe according to embodiments of the present invention for from receive after digital signal extensive The equipment of multiple initial data.This equipment can be arranged in the receiver of optical communication system.

As shown in Figure 4, receiver 400 can include optical-electrical converter 401, analog-digital converter 402, number Word processing circuit 403 and the setting for the digital signal recovery initial data after receiving according to the present invention Standby 404.Equally, here, portion directly related with embodiments of the invention in receiver is merely illustrated Point, and eliminate for receiver, be probably necessity, but phase not direct with embodiments of the invention The part closed.

Optical-electrical converter 401 can carry out opto-electronic conversion (i.e., to the optical signal received from transmitter 300 Optical modulator) to be converted into the signal of telecommunication.

The described signal of telecommunication can be converted from analog into digital signal by analog-digital converter 402.

Described digital signal can be included by digital processing circuit 403 according to mode well known in the art The Digital Signal Processing of dispersion compensation, clock recovery and adaptive-filtering, thus obtain shown in above formula (1) Digital signal.Then, digital processing circuit 403 can carry out frequency difference estimation and benefit to this digital signal Repay and differ estimation and compensate.Digital processing circuit 403 can use the blind estimate being described above Method calculates frequency difference and difference.As described above, for frequency difference, there is multiple solution Δ f and Δ f+N_fB/M, For difference, there is multiple solution θ and θ+2 π N_θ/M.In an embodiment of the present invention, digital processing circuit 403 can arbitrarily select a solution of frequency difference as estimated frequency difference, and can arbitrarily select difference A solution as estimated difference.Then, digital processing circuit 403 can be to above formula (1) Suo Shi Signal carry out frequency difference compensation and difference compensate.

Based on the digital signal after this compensation, demodulation the M-PSK through Digital Signal Processing are i.e. carried out Complex signal, equipment 404 can recover the initial data sent in transmitters.Below with reference to Fig. 4 This equipment 404 is described.

As shown in Figure 4, the digital signal after receiving that is used for according to embodiments of the present invention recovers original number According to equipment 404 include judgment device 4041 and decoding apparatus 4042.

Judgment device 4041 can carry out bit decision to described digital signal, to obtain judgement data.Sentence Certainly device 4041 can carry out above-mentioned bit decision to use mode well known in the art, here omits it Describe in detail.

Decoding apparatus 4042 can carry out second differnce decoding to described judgement data, thus recovers launching The initial data sent in machine.Specifically, to the i-th+2 data Z in described judgement data '_i+2, solve Code device 4042 can carry out second differnce decoding according to above formula (12) to it, to produce decoded number According to X '_i+2, as described initial data.The concrete mode decoded due to this second differnce and phase mentioned above With, the most here omit it and describe in detail.As described above, by carrying out this differential decoding, permissible Recover the initial data sent in transmitters.Such that make to obtain when estimating in frequency difference estimation and difference Obtain frequency difference and multiple ambiguous solutions of difference, cause carrier auxiliary mistake, also will not therefore affect number subsequently According to the correctness recovered.

Compared with traditional carrier restorer, said method and equipment according to embodiments of the present invention are prone to Realize, therefore there is wide applicability.Additionally, said method according to embodiments of the present invention and equipment Having the strongest robustness, even if under the extreme case of the frequent shear of frequency, every secondary frequencies shear is also only The output result of several code elements when affecting shear, i.e. substantially without affecting the correctness that data are recovered.

Although it should be appreciated that hereinbefore describe the present invention under the background of optical communication system, but It is can also be applied to other communication systems, such as wireless communication system, in such a case, it is possible to Light carrier mentioned above is replaced with electricity carrier wave.

While there has been shown and described that the example embodiment of the present invention, it will be appreciated by those skilled in the art that In the case of the scope and spirit of the present invention limited in without departing substantially from appended claims and their equivalents, permissible These example embodiment are made the change on various forms and details.

Claims (6)

1. the side of the digital signal recovery initial data in coherent optical communication system after receiving Method, including:

Described digital signal is carried out bit decision, to obtain judgement data；And

After blind estimate, described judgement data are carried out second differnce decoding, thus recover initial data, So that the initial data recovered is not affected by carrier auxiliary ambiguous solution based on blind estimate, described blind estimate Carrier auxiliary include frequency difference estimation and compensation, differ estimation and compensate.

The most described digital signal has been by demodulation and has passed through The M-PSK complex signal of Digital Signal Processing, M=2ⁿ, n is the integer more than 1.

3. described judgement data wherein, are carried out second differnce decoding by method as claimed in claim 2, Thus recover initial data and include:

The i-th+2 data Z in described judgement data '_i+2, according to the following formula it is carried out second differnce solution Code, to produce decoded data X '_i+2, as described initial data:

X'_i+2=(Z'_i+2-2Z'_i+1-Z'_i)Mod(M)

Wherein, Z '_i+1And Z '_iBeing respectively i+1 the data in described judgement data and i-th data, i is just Integer.

4. the digital signal in coherent optical communication system after receiving recovers setting of initial data Standby, including:

Judgment device, is configured to digital signal is carried out bit decision, to obtain judgement data；And

Decoding apparatus, is configured to after blind estimate, and described judgement data are carried out second differnce decoding, Thus recover initial data, so that the initial data recovered is not by carrier auxiliary ambiguity based on blind estimate Solving impact, the carrier auxiliary of described blind estimate includes frequency difference estimation and compensation, differ estimation and compensation.

5. equipment as claimed in claim 4, wherein, described digital signal has been by demodulation and has passed through The M-PSK complex signal of Digital Signal Processing, M=2ⁿ, n is the integer more than 1.

6. equipment as claimed in claim 5, wherein, described decoding apparatus is in described judgement data The i-th+2 data Z '_i+2, according to the following formula it is carried out second differnce decoding, to produce decoded data X’_i+2, as described initial data:

X'_i+2=(Z'_i+2-2Z'_i+1-Z'_i)Mod(M)

Wherein, Z '_i+1And Z '_iBeing respectively i+1 the data in described judgement data and i-th data, i is just Integer.