CN103731382A - Method for correcting IQ imbalance of terminal - Google Patents

Abstract

The invention provides a method for correcting IQ imbalance of a terminal. The method includes the following steps: (1) adopting an auxiliary correcting device to receive a specific correcting signal sent by the terminal or send the specific correcting signal to the terminal, wherein the IQ imbalance does not exist in sending and receiving of the auxiliary correcting device; (2) calculating the IQ imbalance correcting coefficient of sending or receiving of the terminal according to the signal received by a receiver, and (3) when the terminal normally works, carrying out correcting compensation according to the IQ imbalance correcting coefficient. According to the method, the IQ imbalance is corrected, meanwhile, the processing procedures of the terminal are simplified, and cost is saved.

Description

The unbalanced bearing calibration of a kind of terminal IQ

Technical field

The present invention relates to signal process field, relate in particular to the unbalanced bearing calibration of a kind of terminal IQ.

Background technology

In communication system, radio frequency or intermediate-freuqncy signal frequency reducing are converted in baseband signal and inverse process thereof, can separation introduce component (I) and quadrature component (Q) in the same way, I/Q component is used gain cosine and sine wave identical and phase phasic difference 90 degree to reach.In the process of carrying out at analog domain due to frequency reducing and raising frequency, have the error of gain and phase place, thereby it is uneven to have introduced IQ between cosine and sine wave, this IQ imbalance can directly cause receiving and the deterioration of transmitting chain signal, affects communication quality.

Existingly for the unbalanced bearing calibration of IQ, concentrate on end side, normally by hardware, increase correcting circuit or complete the unbalanced correction of IQ in conjunction with the corresponding correcting algorithm of software.These methods, when realizing correction, can be introduced complicated handling process and the expense of hardware cost in end side, affect treatment effeciency and the Realization of Product of terminal.

Summary of the invention

For above-mentioned deficiency, the present invention proposes the unbalanced bearing calibration of a kind of terminal IQ, comprise the following steps:

A, adopts auxiliary calibration equipment, the particular calibration signal of receiving terminal transmitting or to terminal transmitting particular calibration signal, transmitting and receiving of described auxiliary calibration equipment all do not exist IQ uneven;

B, the signal receiving according to recipient, the IQ disequilibrium regulating coefficient of the transmitting of computing terminal or reception;

C, when terminal is normally worked, carries out rectification building-out according to IQ disequilibrium regulating coefficient.

Preferably, the present invention is for the reception IQ disequilibrium regulating of terminal, and each step is specially:

In step a, auxiliary calibration equipment is launched simple signal to terminal;

In step b, the reception signal of terminal is done to FFT, P is for receiving the frequency point information corresponding to actual frequency of signal, and N is for receiving the frequency point information corresponding to image frequency of signal, then the reception IQ disequilibrium regulating coefficient E of computing terminal _rand D _r: $E_r=-\mathrm{real}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right),$ $D_r=-\mathrm{imag}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right);$

In step c, when terminal is normally worked, according to E _rand D _rcarry out to received signal IQ disequilibrium regulating compensation: I _rcorr(t)=(E _r+ 1) I _r(t), Q _rcorr(t)=Q _r(t)+D _ri _r(t), I wherein _r(t) for receiving the component in the same way of signal, I _rcorr(t) be the component in the same way of the reception signal after proofreading and correct, Q _r(t) for receiving the quadrature component of signal, Q _rcorr(t) be the quadrature component of the reception signal after proofreading and correct.

Preferably, the present invention is for the transmitting IQ disequilibrium regulating of terminal, and each step is specially:

In step a, terminal is to auxiliary calibration equipment transmitting two-frequency signal, and it is identical that described two-frequency signal comprises amplitude, and frequency is ω ₀and ω ₁two simple signals, ω ₁=2 ω ₀;

In step b, the reception signal of auxiliary calibration equipment is done to FFT, P ₀, P ₁being respectively frequency is ω ₀, ω ₁the frequency point information corresponding to actual frequency of reception signal, N ₀, N ₁being respectively frequency is ω ₀, ω ₁the frequency point information corresponding to image frequency of reception signal, the transmitting IQ disequilibrium regulating coefficient E of computing terminal then _tand D _t: $E_t=1/\mathrm{real}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right)-1,$ $D_t=-(E_t+1)\mathrm{imag}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right),$ Wherein $P_0^{\′}=\frac{P_0}{\frac{P_1}{P_0}},$ $N_0^{\′}=\frac{N_0}{\frac{N_1}{N_0}},$

In step c, when terminal is normally worked, according to E _tand D _tto transmitting, carry out IQ disequilibrium regulating compensation: I _tcorr(t)=(1+E _t) I _t(t), Q _tcorr(t)=Q _t(t)+D _ti _t(t), I wherein _t(t) component in the same way for transmitting, I _tcorr(t) be the component in the same way transmitting after proofreading and correct, Q _t(t) quadrature component for transmitting, Q _tcorr(t) be the quadrature component transmitting after proofreading and correct.

The orthogonality of the i/q signal below terminal of carrying out after IQ disequilibrium regulating being received is verified.

Auxiliary calibration equipment is ω to terminal tranmitting frequency ₀simple signal, in the ideal case, the I/Q expression formula of the reception signal of terminal is:

S(t)=I(t)+jQ(t)，

Wherein mutually orthogonal I/Q two paths of signals is expressed as:

I(t)＝Acos(ω ₀t)

Q(t)=Asin(ω ₀t)

Owing to assisting transmitting and the receiver of calibration equipment all not to exist IQ uneven, the IQ unbalanced factor in trimming process is drawn by end side.The signal I/Q two-way that terminal receives can be expressed as:

I _r(t)=(1+α)Acos(ω0 _t)

Q _r(t)=Asin(ω ₀t+ε)

Wherein, α is introduced by amplitude imbalance, and ε is introduced by unbalance in phase.

According to Euler's formula, deriving obtains the signal that terminal receives and is:

$S_r=I_r\left(t\right)+j{Q}_r\left(t\right)$

$=(1+\mathrm{\α})A\cos \left({\mathrm{\ω}}_{0}t\right)+\mathrm{jA}\sin ({\mathrm{\ω}}_{0}t+\mathrm{\ϵ})$

$=(1+\mathrm{\α})A\frac{e^{j{\mathrm{\ω}}_{0}t}+e^{-j{\mathrm{\ω}}_{0}t}}{2}+\mathrm{jA}\frac{e^{j({\mathrm{\ω}}_{0}t+\mathrm{\ϵ})}-e^{-j({\mathrm{\ω}}_{0}t+\mathrm{\ϵ})}}{2j}$

$=\frac{A}{2}(1+\mathrm{\α}+e^{\mathrm{j\ϵ}})e^{j{\mathrm{\ω}}_{0}t}+\frac{A}{2}(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-j{\mathrm{\ω}}_{0}t}$

The signal that terminal is received is FFT, consider while being FFT sampled point might not from t constantly value, but may from t+ τ constantly, above formula becomes:

$S_r=\frac{A}{2}(1+\mathrm{\α}+e^{\mathrm{j\ϵ}})e^{j{\mathrm{\ω}}_0(t+\mathrm{\τ})}+\frac{A}{2}(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-j{\mathrm{\ω}}_0(t+\mathrm{\τ})}$

$=\frac{A}{2}(1+\mathrm{\α}+e^{\mathrm{j\ϵ}})e^{j{\mathrm{\ω}}_0\mathrm{\τ}}{e}^{j{\mathrm{\ω}}_{0}t}+\frac{A}{2}(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-j{\mathrm{\ω}}_0\mathrm{\τ}}{e}^{-j{\mathrm{\ω}}_{0}t}$

Because P is for receiving the frequency point information corresponding to actual frequency of signal, N, for receiving the frequency point information corresponding to image frequency of signal, makes γ=ω ₀τ, has:

$P=\frac{A}{2}(1+\mathrm{\α}+e^{\mathrm{j\ϵ}})e^{\mathrm{j\γ}}$

$N=\frac{A}{2}(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-\mathrm{j\γ}}$

The reception IQ disequilibrium regulating coefficient E of terminal _rand D _rfor:

$E_r=-\mathrm{real}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right)$

$=-\mathrm{real}\left(\frac{2(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-\mathrm{j\γ}}}{\mathrm{conj}\left((1+\mathrm{\α}+e^{\mathrm{j\ϵ}})e^{\mathrm{j\γ}}\right)+(1+\mathrm{\α}-e^{-\mathrm{j\ϵ}})e^{-\mathrm{j\γ}}}\right)$

$=-\frac{1+\mathrm{\α}-\cos \mathrm{\ϵ}}{1+\mathrm{\α}}$

$=\frac{\cos \mathrm{\ϵ}}{1+\mathrm{\α}}-1$

$D_r=-\mathrm{imag}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right)$

$=-\frac{\sin \mathrm{\ϵ}}{1+\mathrm{\α}}$

When terminal is normally worked, according to E _rand D _rcarry out to received signal after the compensation of IQ disequilibrium regulating, the I/Q two paths of signals after correction is:

$I_{\mathrm{rcorr}}\left(t\right)=(E_r+1)I_r\left(t\right)$

$=\frac{\cos \mathrm{\ϵ}}{1+\mathrm{\α}}(1+\mathrm{\α})A\cos \left({\mathrm{\ω}}_{0}t\right)$

$=A\cos \mathrm{\ϵ}\cos \left({\mathrm{\ω}}_{0}t\right)$

$Q_{\mathrm{rcorr}}\left(t\right)=Q_r\left(t\right)+D_r{I}_r\left(t\right)$

$=A\sin ({\mathrm{\ω}}_{0}t+\mathrm{\ϵ})-\frac{\sin \mathrm{\ϵ}}{1+\mathrm{\α}}(1+\mathrm{\α})A\cos \left({\mathrm{\ω}}_{0}t\right)$

$=A\sin \left({\mathrm{\ω}}_{0}t\right)\cos \mathrm{\ϵ}+A\cos \left({\mathrm{\ω}}_{0}t\right)\sin \mathrm{\ϵ}-A\sin \mathrm{\ϵ}\cos \left({\mathrm{\ω}}_{0}t\right)$

$=A\cos \mathrm{\ϵ}\sin \left({\mathrm{\ω}}_{0}t\right)$

As can be seen from the above equation, the complete quadrature of reception signal after IQ disequilibrium regulating, the amplitude after correction is Acos ε, can effectively solve the unbalanced problem of IQ that receives.

Same, to carrying out the orthogonality of the i/q signal of the terminal transmitting after IQ disequilibrium regulating, verify below.

Terminal is identical to auxiliary calibration equipment transmitting amplitude, and frequency is ω ₀and ω ₁=2 ω ₀two tone signals, without the terminal of IQ disequilibrium regulating, transmit as shown in the formula expression:

S _t=I _t(t)+jQ _t(t)

Wherein, I/Q two-way is expressed as:

I _t(t)=(1+α)Acos(ω ₀t)

Q _t(t)=Asin(ω ₀t+ε)

Because auxiliary calibration equipment receives transmitting through certain phase rotating of self terminal, the signal that auxiliary calibration equipment receives can be expressed as:

$S_{\mathrm{ate}}=S_t{e}^{\mathrm{j\φ}}$

$=(I_1\left(t\right)+{\mathrm{jQ}}_1\left(t\right))e^{\mathrm{j\φ}}$

$==\frac{A}{2}((1+\mathrm{\α})+e^{\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{\mathrm{j\γ}}{e}^{j{\mathrm{\ω}}_{0}t}+\frac{A}{2}((1+\mathrm{\α})-e^{-\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{-\mathrm{j\γ}}{e}^{-j{\mathrm{\ω}}_{0}t}$

Due to P ₀for frequency is ω ₀the frequency point information corresponding to actual frequency of reception signal, N ₀for frequency is ω ₀the frequency point information corresponding to image frequency of reception signal, have:

$P_0=\frac{A}{2}(\left(1+\mathrm{\α}\right)+e^{\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{\mathrm{j\γ}}$

$N_0=\frac{A}{2}(\left(1+\mathrm{\α}\right)-e^{-\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{-\mathrm{j\γ}}$

In like manner, due to P ₁for frequency is ω ₁the frequency point information corresponding to actual frequency of reception signal, N ₁for frequency is ω ₁the frequency point information corresponding to image frequency of reception signal, have:

$P_1=\frac{A}{2}(\left(1+\mathrm{\α}\right)+e^{\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{j2\mathrm{\γ}}$

$N_1=\frac{A}{2}(\left(1+\mathrm{\α}\right)-e^{-\mathrm{j\ϵ}})e^{\mathrm{j\φ}}{e}^{-j2\mathrm{\γ}}$

:

$e^{\mathrm{j\γ}}=\frac{P_1}{P_0}=\frac{N_0}{N_1}$

So have:

$P_0^{\′}=\frac{P_0}{\frac{P_1}{P_0}}=\frac{P_0}{e^{\mathrm{j\γ}}}=\frac{A}{2}((1+\mathrm{\α})+e^{\mathrm{j\ϵ}})e^{\mathrm{j\φ}}$

$N_0^{\′}=\frac{N_0}{\frac{N_1}{N_0}}=N_0*e^{\mathrm{j\γ}}=\frac{A}{2}((1+\mathrm{\α})-e^{-\mathrm{j\ϵ}})e^{\mathrm{j\φ}}$

$\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}=\frac{2(1+\mathrm{\α})+e^{\mathrm{j\ϵ}}-e^{-\mathrm{j\ϵ}}}{e^{\mathrm{j\ϵ}}+e^{-\mathrm{j\ϵ}}}$

$=\frac{1+\mathrm{\α}+j\sin \mathrm{\ϵ}}{\cos \mathrm{\ϵ}}$

$=\frac{1+\mathrm{\α}}{\cos \mathrm{\ϵ}}+j\tan \mathrm{\ϵ}$

The transmitting IQ disequilibrium regulating coefficient E of terminal _tand D _tfor:

$E_t=1/\mathrm{real}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right)-1$

$=\frac{\cos \mathrm{\ϵ}}{1+\mathrm{\α}}-1$

$D_t=-(E+1)\mathrm{imag}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right)$

$=-\frac{\cos \mathrm{\ϵ}}{1+\mathrm{\α}}\tan \mathrm{\ϵ}$

$=-\frac{\sin \mathrm{\ϵ}}{1+\mathrm{\α}}$

When terminal is normally worked, according to E _tand D _tto transmitting, carry out after the compensation of IQ disequilibrium regulating, the I/Q two paths of signals after correction is:

I _tcorr(t)=(1+E _t)I _t(t)

=(1+E _t)(1+α)Acos(ω ₀t)

=Acosεcos(ω ₀t)

Q _tcorr(t)=Q _t(t)+D _tI _t(t)

=Asin(ω ₀t+ε)+D _t(1+α)Acos(ω ₀t)

=Acosεsin(ω ₀t)

As can be seen from the above equation, the complete quadrature that transmits after IQ disequilibrium regulating, the amplitude after correction is Acos ε, efficiently solves equally the unbalanced problem of transmitting IQ.

The present invention passes through by auxiliary calibration equipment, coordinate terminal to receive and transmitting particular calibration signal, the calculating of the reception of complete paired terminal and transmitting IQ disequilibrium regulating coefficient, terminal only need, in course of normal operation, be carried out the rectification building-out to corresponding fixed coefficient on I/Q component.When its advantage is mainly to realize IQ disequilibrium regulating, simplify the handling process of terminal, saved cost expense.In addition, IQ disequilibrium regulating coefficient of the present invention obtains computational methods, also simple and fast very.

Accompanying drawing explanation

Fig. 1 is auxiliary equipment and the terminal connection diagram of the embodiment of the present invention;

Fig. 2 is that the terminal of the embodiment of the present invention receives IQ disequilibrium regulating process schematic diagram;

Fig. 3 is the terminal transmitting IQ disequilibrium regulating process schematic diagram of the embodiment of the present invention.

Embodiment

Below in conjunction with accompanying drawing, by specific embodiment, the present invention is described in further details.

First the present embodiment connects PC, auxiliary calibration equipment, router, terminal to be corrected by shown in Fig. 1, PC is connected with terminal with auxiliary calibration equipment by the network interface of router, controls reception and transmitting calibration signal that auxiliary calibration equipment and terminal are eated dishes without rice or wine.

It is as follows that the present embodiment receives the unbalanced trimming process of IQ to terminal:

Auxiliary calibration equipment is launched tone signal to terminal, terminal is FFT after receiving tone signal to received signal, frequency point information corresponding to actual frequency that note receives signal is P, frequency point information corresponding to image frequency that receives signal is N, then the reception IQ disequilibrium regulating coefficient E of basis formula computing terminal below _rand D _r:

$E_r=-\mathrm{real}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right),$ $D_r=-\mathrm{imag}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right).$

Terminal calculates and receives correction coefficient E _rand D _rafter, be recorded in terminal flash.When terminal is normally worked, read the reception IQ disequilibrium regulating coefficient E in self flash _rand D _r, according to the receiving course shown in Fig. 2, according to formula below, at numeric field, receive IQ imbalance compensation.

I _rcorr(t)=(E _r+1)I _r(t)，Q _rcorr(t)=Q _r(t)+D _rI _r(t)，

I _r(t) for terminal, receive the component in the same way of signal, I _rcorr(t) be the component in the same way of the reception signal after proofreading and correct, Q _r(t) for terminal, receive the quadrature component of signal, Q _rcorr(t) be the quadrature component of the reception signal after proofreading and correct.

It is as follows that the present embodiment is launched the unbalanced trimming process of IQ to terminal:

PC eats dishes without rice or wine to launch a two-frequency signal by network interface control terminal, and it is identical that this two-frequency signal comprises amplitude, and frequency is ω ₀and ω ₁=2 ω ₀two simple signals, PC controls auxiliary calibration equipment by network interface and eats dishes without rice or wine to receive signal simultaneously, here two simple signals being combined into a two-frequency signal and sending together, is that the parameters such as time delay in order to make two simple signals, skew are consistent, to guarantee to calibrate the accuracy of effect.

Auxiliary calibration equipment is FFT after receiving signal to received signal, and note frequency is ω ₀the frequency point information corresponding to actual frequency of reception signal be P ₀, frequency is ω ₀the frequency point information corresponding to image frequency of reception signal be N ₀, frequency is ω ₁the frequency point information corresponding to actual frequency of reception signal be P ₁, frequency is ω ₁the frequency point information corresponding to image frequency of reception signal be N ₁, then according to the transmitting IQ disequilibrium regulating coefficient E of formula computing terminal below _tand D _t:

$E_t=1/\mathrm{real}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right)-1,$ $D_t=-(E_t+1)\mathrm{imag}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right),$

Wherein $P_0^{\′}=\frac{P_0}{\frac{P_1}{P_0}},$ $N_0^{\′}=\frac{N_0}{\frac{N_1}{N_0}}.$

Auxiliary calibration equipment calculates transmitting correction coefficient E _tand D _tafter, result of calculation is fed back to PC by network interface, PC side directly passes to terminal by transmitting correction coefficient by network interface without calculating, and after terminal is received, is recorded in flash.

When terminal is normally worked, read the transmitting IQ disequilibrium regulating coefficient E in self flash _tand D _t, according to the emission process shown in Fig. 3, according to formula below, at numeric field, launch IQ imbalance compensation.

I _tcorr(t)=(1+E _t)I _t(t)，Q _tcorr(t)=Q _t(t)+D _tI _t(t)，

I _t(t) component in the same way transmitting for terminal, I _tcorr(t) be the component in the same way transmitting after proofreading and correct, Q _t(t) quadrature component transmitting for terminal, Q _tcorr(t) be the quadrature component transmitting after proofreading and correct.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any modifications of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.

Claims (3)

1. the unbalanced bearing calibration of terminal IQ, is characterized in that, comprises the following steps:

A, adopts auxiliary calibration equipment, the particular calibration signal of receiving terminal transmitting or to terminal transmitting particular calibration signal, transmitting and receiving of described auxiliary calibration equipment all do not exist IQ uneven;

B, the signal receiving according to recipient, the IQ disequilibrium regulating coefficient of the transmitting of computing terminal or reception;

C, when terminal is normally worked, carries out rectification building-out according to IQ disequilibrium regulating coefficient.

2. according to the method for claim 1, it is characterized in that: for the reception IQ disequilibrium regulating of terminal, each step is specially:

Step a, auxiliary calibration equipment is launched simple signal to terminal;

Step b, is FFT by the reception signal of terminal, and P is for receiving the actual frequency pair of signal

The frequency point information of answering, N is for receiving the frequency point information corresponding to image frequency of signal, then the reception IQ disequilibrium regulating coefficient E of computing terminal _rand D _r: $E_r=-\mathrm{real}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right),$ $D_r=-\mathrm{imag}\left(\frac{2N}{\mathrm{conj}\left(P\right)+N}\right);$

Step c, when terminal is normally worked, according to E _rand D _rcarry out to received signal IQ disequilibrium regulating compensation: I _rcorr(t)=(E _r+ 1) I _r(t), Q _rcorr(t)=Q _r(t)+D _ri _r(t), I wherein _r(t) for receiving the component in the same way of signal, I _rcorr(t) be I _r(t) component in the same way of the reception signal after correction, Q _r(t) for receiving the quadrature component of signal, Q _rcorr(t) be the quadrature component of the reception signal after proofreading and correct.

3. method claimed in claim 1, is characterized in that, for the transmitting IQ disequilibrium regulating of terminal, each step is specially:

Step a, terminal is to auxiliary calibration equipment transmitting two-frequency signal, and it is identical that described two-frequency signal comprises amplitude, and frequency is ω ₀and ω ₁two simple signals, ω ₁=2 ω ₀;

Step b, is FFT, P by the reception signal of auxiliary calibration equipment ₀, P ₁being respectively frequency is ω ₀, ω ₁the frequency point information corresponding to actual frequency of reception signal, N ₀, N ₁being respectively frequency is ω ₀, ω ₁the frequency point information corresponding to image frequency of reception signal, the transmitting IQ disequilibrium regulating coefficient E of computing terminal then _tand D _t: $E_t=1/\mathrm{real}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right)-1,$ $D_t=-(E_t+1)\mathrm{imag}\left(\frac{P_0^{\′}+N_0^{\′}}{P_0^{\′}-N_0^{\′}}\right),$ Wherein $P_0^{\′}=\frac{P_0}{\frac{P_1}{P_0}},$ $N_0^{\′}=\frac{N_0}{\frac{N_1}{N_0}},$

Step c, when terminal is normally worked, according to E _tand D _tto transmitting, carry out IQ disequilibrium regulating compensation: I _tcorr(t)=(1+E _t) I _t(t), Q _tcorr(t)=Q _t(t)+D _ti _t(t), I wherein _t(t) component in the same way for transmitting, I _tcorr(t) be the component in the same way transmitting after proofreading and correct, Q _t(t) quadrature component for transmitting, Q _tcorr(t) be the quadrature component transmitting after proofreading and correct.

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