KR20190022103A - Apparatus and method for calibrating i/q imbalance of direct-conversion transmitter - Google Patents

Abstract

The present invention relates to an apparatus and a method for compensating an I/Q imbalance in a direct conversion transmitter. Through a method in which a control unit for measuring a reference RSB, which is an RSB of a signal outputted from a direct conversion transmitter, with respect to an in-phase signal (I_D) and a quadrature phase signal (Q_D) of a digital baseband inputted to the direct conversion transmitter measures an additional RSB, which is an RSB of a signal outputted from the direct conversion transmitter, according to a gain mismatch parameter (g_a) or a phase mismatch parameter (θ_a) inputted to the digital baseband, a gain error parameter (g_(err)) and a phase error parameter (θ_(err)) of the direct conversion transmitter are determined, and the gain error parameter (g_(err)) and the phase error parameter (θ_(err)) are used for I/Q imbalance compensation of the direct conversion transmitter. According to the present invention, simple and accurate compensation is possible.

Description

[0001] APPARATUS AND METHOD FOR CALIBRATING I / Q IMMBALANCE OF DIRECT-CONVERSION TRANSMITTER [0002]

The present invention relates to an apparatus and method for compensating I / Q imbalance of a direct-conversion transmitter through RSB (Residual Side-Band) measurement in a simple but precise manner.

Generally, in a communication system, an in-phase signal (I _D ) and a quadrature signal (Q _D ) having a phase difference of 90 ° with the in-phase signal are transmitted in order to transmit a large amount of information within a given bandwidth. Is used as the orthogonal modulated signal. Among such devices for generating such quadrature modulated signals are direct conversion transmitters, and direct conversion transmitters are widely used in communication systems because they are small and operate at low cost.

1 is a schematic diagram of an I / Q imbalance compensation apparatus of a direct conversion transmitter according to an embodiment of the present invention.

1, the direct conversion transmitter 1 includes two DACs (Digital to Analog Converters) 11 and 12, two low-pass filters 21 and 22, two mixers 31 and 32, An oscillator 40 and an adder 50. [

The digital baseband in-phase signal I _D is input to the first DAC 11 and the digital baseband quadrature signal Q _D is input to the second DAC 12. The in-phase signal I _D and the quadrature signal Q _D are digital signals and the first DAC 11 converts the in-phase signal I _D into an analog signal. The second DAC 12 converts the in- Converts the quadrature-phase signal (Q _D ) into an analog signal.

The first low pass filter 21 generates an in-phase analog signal I _A by removing a high-frequency component from the in-phase signal converted into an analog signal, and the second low-pass filter 22 generates an in- And removes high-frequency components from the phase signal to generate a quadrature-phase analog signal Q _A.

The first mixer 31 mixes the in-phase analog signal I _{A with} an in-phase local oscillator signal LO _I generated by the local oscillator 40 and the second mixer 32 mixes the quadrature analog signal Q _A ) with a quadrature-phase local oscillator signal (LO _Q ) generated by a local oscillator (40).

The adder 50 adds or subtracts the signals output from the first mixer 31 and the second mixer 32 to generate a lower sideband or an upper sideband orthogonal modulation signal, the resulting quadrature modulated signal is the same, the phase signal (I _D) and the quadrature signal (Q _D) because it has, in the receiving end demodulates the quadrature modulated signal in-phase signal (I _D) and the quadrature signal (Q _D) .

As such, the direct conversion transmitter 1 has an in-phase signal and a quadrature signal, both of which must be orthogonal with a phase difference of exactly 90 [deg.]. However, because of the analog nature of a direct conversion transmitter (1) in-phase signal (I _D) and the quadrature signal (Q _D) and the gain imbalance gain is varied between, in-phase signal (I _D) and the quadrature signal (Q _D) A phase imbalance in which the phase difference is shifted by 90 degrees may occur. In this case, there is a problem that when the quadrature modulated signal is demodulated by the receiving end, the demodulation performance is seriously deteriorated. Accordingly, it is necessary to provide a technique for compensating for the I / Q imbalance of the direct conversion transmitter 1 as in Patent Document 1 below.

Korean Patent Registration No. 1455894 (published on October 22, 2014).

SUMMARY OF THE INVENTION It is an object of the present invention to provide an I / Q imbalance compensation apparatus and method capable of compensating an I / Q imbalance of a direct conversion transmitter in a simple and accurate manner.

In order to achieve the above object, an I / Q imbalance compensation apparatus of a direct conversion transmitter according to the present invention includes an in-phase signal I _D and a quadrature-phase signal Q _D An RSB measuring unit for measuring RSB (Residual Side-Band) of a signal output from the direct conversion transmitter as a reference RSB; And a controller for inputting a gain mismatch parameter g _a or a phase mismatch parameter θ _a to the digital baseband, wherein the RSB measurer calculates the gain mismatch parameter g the RSB of the signal output from the direct conversion transmitter is measured as an additional RSB according to _a ) or a phase mismatch parameter (? _a ), and the control unit uses the reference RSB and the additional RSB measured by the RSB measuring unit by the direct conversion gain error parameter (g _err) and the phase error parameter (θ _err) crystal, and the inverse compensation values of said gain error parameter (g _err) and the phase error parameter (θ _err) the digital baseband transmitter To compensate the I / Q imbalance of the direct conversion transmitter.

Here, the controller inputs _a gain mismatch parameter g _a to the digital baseband, and the RSB measurer obtains RSB of the signal output from the direct conversion transmitter in accordance with the input of the gain mismatch parameter g _a And the control unit further inputs _a phase mismatch parameter (? _A ) to the digital baseband, and the RSB measuring unit measures the phase mismatch parameter (? _A ) as a first additional RSB, And the controller calculates the gain error parameter g _err and the phase error parameter? _Err using the reference RSB, the first additional RSB, and the second additional RSB as the second additional RSB .

Alternatively, the controller is the RSB of the signal output from the direct conversion transmitter according to an input of the phase-mismatch parameter (θ _a) enter the phase mismatch parameter (θ _a) in the digital baseband, and the RSB measurement unit And the control section further inputs _a gain mismatch parameter g _a to the digital baseband, and the RSB measuring section measures the gain mismatch parameter g _a as a first additional RSB, And the controller calculates the gain error parameter g _err and the phase error parameter? _Err using the reference RSB, the first additional RSB, and the second additional RSB as the second additional RSB .

Alternatively, the controller may input _a gain mismatch parameter g _a to the digital baseband, and the RSB measurer may calculate an RSB of the signal output from the direct conversion transmitter in accordance with the input of the gain mismatch parameter g _a And the controller inputs the phase mismatch parameter (? _A ) instead of the gain mismatch parameter (g _a ) to the digital baseband, and the RSB measurer obtains the phase mismatch parameter? according to the input of _a) measures the RSB of the signal output from the direct conversion transmitter as a second additional RSB, the controller is the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err And a phase error parameter? _Err .

Alternatively, the controller is the RSB of the signal output from the direct conversion transmitter according to an input of the phase-mismatch parameter (θ _a) enter the phase mismatch parameter (θ _a) in the digital baseband, and the RSB measurement unit And the control unit inputs the gain mismatch parameter g _a instead of the phase mismatch parameter θ _a to the digital baseband, and the RSB measurement unit calculates the gain mismatch parameter g according to the input of _a) measures the RSB of the signal output from the direct conversion transmitter as a second additional RSB, the controller is the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err And a phase error parameter? _Err .

Alternatively, the controller may input a gain mismatch parameter g _a and a phase mismatch parameter θ _a to the digital baseband, and the RSB measurer may calculate the gain mismatch parameter g _a and the phase mismatch parameter depending on the input of θ _a) measures the RSB of the signal output from the direct conversion transmitter as a first additional RSB, the controller is the phase mismatch parameter (θ _a) to remove the digital baseband in the digital baseband on and to input only the gain mismatch parameter (g _a), the RSB measurement unit measures the RSB of the signal output from the direct conversion transmitter according to an input of the gain mismatch parameter (g _a) as a second additional RSB and , The controller determines the gain error parameter g _err and the phase error parameter? _Err using the reference RSB, the first additional RSB, and the second additional RSB .

Alternatively, the controller may input a gain mismatch parameter g _a and a phase mismatch parameter θ _a to the digital baseband, and the RSB measurer may calculate the gain mismatch parameter g _a and the phase mismatch parameter θ _a) in accordance with the input measures the RSB of the signal output from the direct conversion transmitter as a first additional RSB, the control unit the by removing the gain mismatch parameter (g _a) in the digital baseband digital baseband in and to enter only the phase mismatch parameter (θ _a), the RSB measurement unit measures the RSB of the signal output from the direct conversion transmitter according to an input of the phase-mismatch parameter (θ _a) as a second additional RSB and the controller determines a gain error parameter (g _err) and the phase error parameter (θ _err) by using the reference RSB, RSB first additional and second additional RSB And that is characterized.

According to another aspect of the present invention, there is provided an I / Q imbalance compensation method for a direct conversion transmitter, including: a digital baseband in-phase signal (I _D ) and a digital baseband quadrature phase Measuring a RSB (Residual Side-Band) of a signal output from the direct conversion transmitter as a reference RSB with respect to the signal (Q _D ); Gain mismatch parameters to the digital baseband (g _a) or the phase mismatch parameter (θ _a) to enter the said direct conversion transmitter according to the gain mismatch parameter (g _a) or the phase mismatch parameter (θ _a) An additional RSB measurement step of measuring the RSB of the signal output from the RSB as an additional RSB; An error parameter determination step of determining a gain error parameter (g _err ) and a phase error parameter (? _Err ) of the direct conversion transmitter using the reference RSB and the additional RSB; And an I / Q imbalance compensation step of inputting the inverse compensation value of the gain error parameter g _err and the phase error parameter? _Err into the digital baseband to compensate the I / Q imbalance of the direct conversion transmitter; .

Here, in the additional RSB measuring step, a gain mismatch parameter g _a is input to the digital baseband, RSB of a signal output from the direct conversion transmitter is measured as a first additional RSB, and phase The RSB of the signal output from the direct conversion transmitter is further input as a second additional RSB by inputting the mismatch parameter? _A further, and in the error parameter determination step, the reference RSB, the first additional RSB, and the second additional RSB And the gain error parameter g _err and the phase error parameter? _Err are determined.

Alternatively, in the additional RSB measurement step, a phase mismatch parameter (? _A ) is input to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter as a first additional RSB, The RSB of the signal output from the direct conversion transmitter is further input as a second additional RSB by inputting the mismatch parameter g _a further, and in the error parameter determination step, the reference RSB, the first additional RSB, and the second additional RSB And the gain error parameter g _err and the phase error parameter? _Err are determined.

Alternatively, in the additional RSB measurement step, a gain mismatch parameter g _a is input to the digital baseband, RSB of a signal output from the direct conversion transmitter is measured as a first additional RSB, The RSB of the signal output from the direct conversion transmitter is measured as a second additional RSB by inputting the phase mismatch parameter? _{A in} place of the gain mismatch parameter g _a , and in the error parameter determination step, , The gain error parameter g _err and the phase error parameter? _Err are determined using the first additional RSB and the second additional RSB.

Alternatively, in the additional RSB measurement step, a phase mismatch parameter (? _A ) is input to the digital baseband to measure the RSB of a signal output from the direct conversion transmitter as a first additional RSB, The gain mismatch parameter g _a is input instead of the phase mismatch parameter θ _a to measure the RSB of the signal output from the direct conversion transmitter as a second additional RSB, and in the error parameter determination step, , The gain error parameter g _err and the phase error parameter? _Err are determined using the first additional RSB and the second additional RSB.

Alternatively, in the additional RSB measuring step, a gain mismatch parameter g _a and a phase mismatch parameter θ _a are input to the digital baseband, and the RSB of the signal output from the direct conversion transmitter is set as a first additional RSB And outputs the RSB of the signal output from the direct conversion transmitter in a state where only the gain mismatch parameter g _a is input to the digital baseband by removing the phase mismatch parameter θ _a from the digital baseband, the second measure as a further RSB, in the error parameter determining step, using the standard RSB, the first additional RSB and second additional RSB of determining the gain error parameter (g _err) and the phase error parameter (θ _err) .

Alternatively, in the additional RSB measuring step, a gain mismatch parameter g _a and a phase mismatch parameter θ _a are input to the digital baseband, and the RSB of the signal output from the direct conversion transmitter is set as a first additional RSB The gain mismatch parameter g _a is removed from the digital baseband and only the phase mismatch parameter θ _a is input to the digital baseband, the RSB of the signal output from the direct conversion transmitter is the second measure as a further RSB, in the error parameter determining step, using the standard RSB, the first additional RSB and second additional RSB of determining the gain error parameter (g _err) and the phase error parameter (θ _err) .

The present invention measures a reference RSB, which is an RSB of a signal output from the direct conversion transmitter, for an in-phase signal I _D and a quadrature-phase signal Q _D of a digital baseband input to a direct conversion transmitter, Through the method of measuring the additional RSB which is the RSB of the signal output from the direct conversion transmitter in accordance with the gain mismatch parameter g _a or the phase mismatch parameter θ _a input to the baseband, error parameter (g _err) and the phase error, and determines the parameters (θ _err), configured to take advantage of the gain error parameter (g _err) and the phase error parameter (θ _err) in the I / Q imbalance compensation in the direct conversion transmitter being , And simple and accurate compensation is possible.

The present invention also satisfies the requirement that the RSB of the signal output from the direct conversion transmitter is measured and the error parameter g _{err ,? Err} is determined via the measured RSB (i.e., the reference RSB and the additional RSB) The advantage is that no additional hardware configuration is required to reduce accuracy.

In addition, the present invention is advantageous in that the calculation efficiency is higher than that of the conventional I / Q imbalance compensation apparatus and method due to the non-repetitive characteristics and quick compensation is possible.

1 is a schematic diagram of an I / Q imbalance compensation apparatus of a direct conversion transmitter according to an embodiment of the present invention.
2 is a diagram illustrating a reference RSB.
3A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a is input to a digital base band, and FIG. 3B is a diagram illustrating a phase mismatch parameter θ _a Lt; RTI ID = 0.0 > RSB < / RTI >
FIG. 4A is _a diagram illustrating a first additional RSB measured when _a phase mismatch parameter θ _a is input to a digital baseband, and FIG. 4B is a diagram illustrating a gain mismatch parameter g _a Lt; RTI ID = 0.0 > RSB < / RTI >
FIG. 5A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a is input to a digital baseband. FIG. 5B is a diagram illustrating a gain mismatch parameter g _a , And the second additional RSB measured when the phase mismatch parameter? _A is input instead.
6A is _a diagram illustrating a first additional RSB measured when _a phase mismatch parameter θ _a is input to _a digital baseband, and FIG. 6B is a diagram illustrating a first additional RSB measured when _a digital baseband And the second additional RSB measured when the gain mismatch parameter g _a is input to the second adder RSB.
7A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a and a phase mismatch parameter _a are input to a digital baseband, And the gain mismatch parameter g _a is input to the digital baseband by removing the phase mismatch parameter θ _a .
8A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a and a phase mismatch parameter _a are input to a digital baseband, A second additional RSB measured when the gain mismatch parameter g _a is removed and only the phase mismatch parameter? _A is input to the digital baseband.
9 is a flowchart of an I / Q imbalance compensation method of a direct conversion transmitter according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the accompanying drawings, like reference numerals refer to like elements. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. In any form. The detailed description of known functions and configurations that may unnecessarily obscure the gist of the present invention will be omitted.

Since the DACs 11 and 12, the low pass filters 21 and 22, the mixers 31 and 32 and the adder 50 of the direct conversion transmitter 1 shown in FIG. 1 are analog components, Is a factor that causes gain unbalance and phase imbalance of I / Q, that is, I / Q imbalance.

In the following, all elements that affect the gain imbalance of the direct conversion transmitter 1 are defined as one parameter, a gain error parameter g _err , and all elements affecting the phase imbalance of the direct conversion transmitter 1 are defined as one Is defined as a phase error parameter θ _{err which} is a parameter.

In the present invention, the gain to be present in a direct conversion transmitter (1) error parameter (g _err) and the phase error parameter (θ _err) for determining back, inverse compensation of the gain error parameter (g _err) and the phase error parameter (θ _err) Value to the digital baseband located at the front end of the direct conversion transmitter 1 to compensate the I / Q imbalance of the direct conversion transmitter 1. [ Also, the present invention proposes a method of determining the gain error parameter g _err and the phase error parameter? _Err through a plurality of RSB (Residual Side-Band) measurements, which will be described in detail below .

는 직접 변환 송신기(1)에 존재하는 게인 에러 파라미터(g_err)와 위상 에러 파라미터(θ_err)로 인해 다음의 수학식 1과 같이 나타낼 수 있다.The up-converting signal generated by the local oscillator 40 shown in FIG.

Can be expressed by the following Equation 1 due to the gain error parameter g _err and the phase error parameter? _Err existing in the direct conversion transmitter 1.

[Equation 1]

이고,

이다.here,

ego,

to be.

를

라 할 때, 직접 변환 송신기(1)의 출력 신호

는 다음의 수학식 2와 같이 나타낼 수 있다.On the other hand, a positive digital baseband signal

To

, The output signal of the direct conversion transmitter 1

Can be expressed by the following equation (2).

&Quot; (2) "

는 상측파대(Upper Side-band) 주파수를 의미하며

이고,

는 하측파대(Lower Side-band) 주파수를 의미하며

이다. here,

Means an upper side-band frequency

ego,

Means a lower side-band frequency

to be.

K ₁ = 1 and K ₂ = 0 when there is no gain imbalance in the direct conversion transmitter 1 (g _err = 0) and no phase imbalance (θ _err = 0) It means that it has only the upper sideband signal as desired.

However, if there is a gain imbalance in the direct conversion transmitter 1 (g _err ≠ 0) or a phase imbalance (θ _err ≠ 0), then the transmitted signal will have not only the upper sideband signal but also the unwanted lower sideband signal. In the communication system, the relationship between the upper sideband signal and the lower sideband signal can be expressed as RSB (Residual Side-band) called residual sideband, and RSB is defined as Equation (3).

&Quot; (3) "

Here, assuming that the gain error parameter and the phase error parameter are small (for example, g _err &_Lt; 0.1, [theta] _err (3? / 180 rad / s), Equation (3) can be simplified as shown in Equation (4) below. Hereinafter, this is referred to as a reference RSB (i.e., a gain mismatch parameter g _a Or the RSB when the phase mismatch parameter? _A is not inputted). And Equation 4 assumes that the I / Q imbalance of the direct conversion transmitter 1 does not occur in the digital baseband, which allows the digital component to generate a relatively accurate quadrature signal as compared to the analog component .

&Quot; (4) "

As shown in FIG. 2, the reference RSB equation can be represented by a circle centered at (0, 0) in a plane consisting of a gain (g) and a phase (?), It is a gain error parameter (g _err) of the transmitter (1) and a phase error parameter (θ _err) exists. A direct conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err), gain mismatch parameter to a digital baseband (g _a) or the phase mismatch parameter (θ _a) order to determine the .

는 다음의 수학식 5와 같이 나타낼 수 있다. 여기서, 게인 미스매치 파라미터(g_a)와 위상 미스매치 파라미터(θ_a)는 직접 변환 송신기(1)의 게인 에러 파라미터(g_err)와 위상 에러 파라미터(θ_err)를 결정하기 위하여, 후술하는 제어부(120)가 디지털 베이스밴드에 입력하는 파라미터이다. 그리고 게인 미스매치 파라미터에 음의 부호(-g_a)를 붙인 이유는 계산상의 편의를 위한 것이다.When a gain mismatch parameter g _a and a phase mismatch parameter _a are input to the digital baseband, a positive digital baseband signal

Can be expressed by the following equation (5). Here, the gain mismatch parameter (g _a) and the phase mismatch parameter (θ _a) is to determine a gain error parameter (g _err) and the phase error parameter (θ _err) of the direct conversion transmitter 1, the control to be described later Which is input to the digital baseband. The reason why the negative sign (-g _a ) is added to the gain mismatch parameter is for convenience of calculation.

&Quot; (5) "

이고,

이다.here,

ego,

to be.

는 다음의 수학식 6과 같이 나타낼 수 있다.The output signal of the direct conversion transmitter 1

Can be expressed by the following Equation (6).

&Quot; (6) "

The RSB is expressed by Equation (7) as in Equation (3).

&Quot; (7) "

Assuming that the gain error parameter and the phase error parameter are small (for example, g _err &_Lt; 0.1, [theta] _err <When the 3π / 180 rad / s), Equation (7) can be simplified as shown in Equation 8, hereinafter, this additional RSB (that is, the gain mismatch parameter to a digital baseband (g _a) or phase And RSB when the mismatch parameter? _A is input).

&Quot; (8) &quot;

The additional RSB equation appears as a circle centering on (g _a , θ _a ) in _a plane consisting of gain (g) and phase (θ).

In order to compensate the I / Q imbalance of the direct conversion transmitter 1, a gain error parameter g _err and a phase error parameter? _Err present in the direct conversion transmitter 1 must be determined, (g) the phase circle appears as having in the plane formed of a (θ) around the (0,0), the equation (8) is in the plane formed by the gain (g) and the phase (θ) (g _a, θ _a) Since the center circle shown as having a, it can be seen that the required order to determine the gain error parameter (g _err) and the phase error parameter (θ _err) of the direct conversion transmitter (1) measuring two or more times RSB.

1, the I / Q imbalance compensator 100 of the direct conversion transmitter according to the present invention may include an RSB measurement unit 110 and a control unit 120. FIG.

The RSB measuring unit 110 measures the phase of the signal output from the direct conversion transmitter 1 with respect to the in-phase signal I _D and the quadrature signal Q _D of the digital baseband input to the direct conversion transmitter 1, The RSB is measured as a reference RSB.

Controller 120 gain error parameter (g _err) and the phase error parameter (θ _err) to determine a gain mismatch parameter to a digital baseband (g _a) or phase mismatches present in a direct conversion transmitter (1) The parameter? _A is input.

Here, the gain mismatch parameter g _a and phase mismatch parameter _a that the control unit 120 inputs to the digital baseband may be a value set by the user in the control unit 120, It can be a set value. That is, the gain mismatch parameter g _a or phase mismatch parameter? _A input to the digital baseband corresponds to values previously known to the control unit 120.

The reason that the controller 120 inputs the gain mismatch parameter g _a or phase mismatch parameter? _A to the digital baseband is that the controller 120 sets the gain mismatch parameter g _a to the digital baseband, Or inputting only the phase mismatch parameter? _A , or inputting both the gain mismatch parameter g _a and the phase mismatch parameter? _A at the same time.

The RSB measuring unit 110 measures the RSB according to the gain mismatch parameter g _a or the phase mismatch parameter? _A inputted to the digital baseband as an additional RSB. That is, the reference RSB means the RSB when the gain mismatch parameter g _a or the phase mismatch parameter? _A is not inputted to the digital baseband as described above, and the additional RSB means the gain error Means an RSB when _a match parameter g _a or a phase mismatch parameter? _A is input.

The control unit 120 receives the gain error parameter g _err and the phase error parameter θ _{err of} the direct conversion transmitter 1 using the reference RSB measured by the RSB measurement unit 110 and one or two additional RSBs, ).

를 입력(즉, 게인 미스매치 파라미터로서

을 입력하고, 위상 미스매치 파라미터로서

을 입력)함으로써 직접 변환 송신기의 I/Q 불균형을 보상할 수 있다.Further, the controller 120 inputs the determined gain error parameter g _err and the inverse compensation value of the phase error parameter? _Err to the digital baseband to compensate the I / Q imbalance of the direct conversion transmitter. More specifically, the control unit 120 controls the digital baseband

(I.e., as a gain mismatch parameter

As a phase mismatch parameter,

The I / Q imbalance of the direct conversion transmitter can be compensated.

The gain error parameter g _err of the direct conversion transmitter 1 and the phase error parameter g _err of the direct conversion transmitter 1 through the I / Q imbalance compensation apparatus of the direct conversion transmitter according to the present invention will now be described with reference to FIGS. 2 through 8B, &lt; / RTI &gt; _err ) will now be described in more detail.

2 is a diagram illustrating a reference RSB.

As described above, the RSB measuring unit 110 measures the phase of the direct conversion transmitter 1 with respect to the in-phase signal I _D and the quadrature-phase signal Q _D of the digital baseband inputted to the direct conversion transmitter 1, As a reference RSB.

)으로 나타나게 된다.In this case, the reference RSB can be expressed as shown in Equation (4), and the schematic of the reference RSB is a circle having a center (0, 0) in the plane consisting of the gain (g) (The radius is

).

2, there are a gain error parameter g _err and a phase error parameter? _Err of the direct conversion transmitter 1 among the respective points constituting a circle. Accordingly, the gain of the direct conversion transmitter (1) error parameter (g _err) and the phase error parameter gain mismatch parameter (g _a) or the phase mismatch parameter in order to determine the (θ _err), the control unit 120 ( θ _a ) into the digital baseband.

Figures 3a to 8b is the control unit 120 is a digital base band gain mismatch parameter (g _a) or the phase mismatch parameter (θ _a), the gain error of the direct conversion transmitter (1) parameter as the input to (g _err ) And the phase error parameter? _Err .

&Lt; Embodiment 1 >

3A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a is input to _a digital baseband.

In order to determine the direct conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err), the controller 120 may enter the gain mismatch parameter (g _a) in a digital baseband, At this time, the RSB measuring unit 110 may measure the RSB of the signal output from the direct conversion transmitter 1 as the first additional RSB according to the input of the gain error parameter g _err .

)으로 나타나게 된다.The first additional RSB may be expressed as Equation (9), and the scheme of the first additional RSB may be represented by a gain g and a phase &amp;thetas; A circle centered at (g _a , 0) in the plane in which it is formed

).

&Quot; (9) &quot;

Referring to FIG. 3A, it can be seen that there are two intersections (ie, sol ₁ and sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet. The intersection at which the reference RSB and the first additional RSB meet can be found by solving the equations (4) and (9), and can be expressed by the following equations (10) and (11).

&Quot; (10) &quot;

&Quot; (11) &quot;

According to Equation (10) and (3a), the gain error parameter g _err is a value (g _a / 2) corresponding to 1/2 of the gain mismatch parameter g _a when the reference RSB and the first additional RSB are equal to each other, , A value located on the right side of g _a / 2 when the reference RSB is larger than the first additional RSB, and a value located on the left of g _a / 2 when the reference RSB is smaller than the first additional RSB ( 3A, it is assumed that the reference RSB is larger than the first additional RSB).

According to Equation (11), when the gain error parameter g _err is determined, it can be known that there are two solutions of the phase error parameter? _Err .

However, a phase error there parameters (θ _err) may be a case that this one year alone exist, since in this case the point of intersection between the dimensions RSB and first additional RSB there be only one, measuring a second additional RSB below It is possible to directly determine the parameter corresponding to the intersection point by using the gain error parameter g _err and the phase error parameter? _Err of the transmitter 1 directly.

However, as shown in FIG. 3A, when there are two intersection points between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), it is assumed that any of the two intersection points is a gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

3B is _a diagram illustrating a second additional RSB measured when the phase mismatch parameter? _A is further input to the digital baseband. In the case where two direct-conversion transmitters are used among two intersections between the reference RSB and the first additional RSB, in order to determine the intersection point corresponding to the gain error parameter (g _err) and the phase error parameter (θ _err) of (1), the control part 120 may further input the phase mismatch parameter (θ _a) in the digital baseband The RSB measuring unit 110 may measure the RSB of the signal output from the direct conversion transmitter 1 as a second additional RSB in response to the input of the phase mismatch parameter θ _a .

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (12) and the second additional RSB may be represented by a gain g and a phase? As shown in FIG. 3B A circle having a center (g _a , θ _a ) in the plane in which it is formed

).

&Quot; (12) &quot;

Referring to Figure 3b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection exists only _(g, θ) Only 1 dog on a plane (that is, sol _1).

The intersection at which the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the controller 120 receiving the equations (4), (9), and (12) together.

이고, 제2 추가 RSB의 크기가 제1 추가 RSB의 크기보다 큰 경우에는

이 됨을 알 수 있으므로, 제어부(120)는 기준 RSB와 제1 추가 RSB를 통해 게인 에러 파라미터(g_err)를 결정한 뒤, 제1 추가 RSB의 크기와 제2 추가 RSB의 크기 비교를 통해 위상 에러 파라미터(θ_err)를 결정할 수도 있다.Alternatively, the intersection point at which the reference RSB, the first additional RSB, and the second additional RSB meet is determined by the controller 120 firstly receiving a gain error parameter (combination of Equations 4 and 9) through the reference RSB and the first additional RSB g _err ) and then comparing the size of the first additional RSB with the size of the second additional RSB. More specifically, referring to FIG. 3B, when the size of the second additional RSB is smaller than the size of the first additional RSB

, And if the size of the second additional RSB is larger than the size of the first additional RSB

The control unit 120 determines the gain error parameter g _err through the reference RSB and the first additional RSB and then compares the size of the first additional RSB with the size of the second additional RSB, ( _err ) may be determined.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

&Lt; Embodiment 2 >

4A is _a diagram illustrating a first additional RSB measured when _a phase mismatch parameter? _A is input to _a digital baseband.

In order to determine the direct conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err), the controller 120 may enter a phase mismatch parameter (θ _a) in a digital baseband, At this time, the RSB measuring unit 110 may measure the RSB of the signal output from the direct conversion transmitter 1 as the first additional RSB according to the input of the phase mismatch parameter θ _a .

)으로 나타나게 된다.The first additional RSB may be expressed by the following Equation (13), and the scheme of the first additional RSB may be represented by a gain g and a phase &amp;thetas; A circle centered on (? _A , 0) in the plane

).

&Quot; (13) &quot;

Referring to FIG. 4A, it can be seen that there are two intersections (ie, sol ₁ , sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet. The intersection at which the reference RSB and the first additional RSB meet can be found by solving the equations (4) and (13), and can be expressed by the following equations (14) and (15).

&Quot; (14) &quot;

&Quot; (15) &quot;

According to Equations (14) and (4), the phase error parameter? _Err is a value? _A / 2 corresponding to 1/2 of the phase mismatch parameter? _A when the reference RSB and the first additional RSB are equal to each other, Is a value located above θ _a / 2 when the reference RSB is larger than the first additional RSB, and is a value located below θ _a / 2 when the reference RSB is smaller than the first additional RSB ( 4A, it is assumed that the reference RSB is larger than the first additional RSB).

According to Equation (15), when the phase error parameter? _Err is determined, it can be known that there are two solutions of the gain error parameter g _err .

However, gain error parameter (g _err) that there may be cases that the one year alone exist, since in this case the point of intersection between the dimensions RSB and first additional RSB there be only one, measuring a second additional RSB below It is possible to directly determine the parameter corresponding to the intersection point by using the gain error parameter g _err and the phase error parameter? _Err of the transmitter 1 directly.

However, as shown in FIG. 4A, when there are two intersection points between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), it is determined which one of the two intersection points is the gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

FIG. 4B is _a diagram illustrating a second additional RSB measured when _a gain mismatch parameter g _a is further input to _a digital baseband, The control unit 120 can further input the gain mismatch parameter g _a to the digital baseband in order to determine an intersection corresponding to the gain error parameter g _err and the phase error parameter _{err er} of the digital baseband signal 1 Accordingly, the RSB measuring unit 110 can measure the RSB of the signal output from the direct conversion transmitter 1 as a second additional RSB according to the input of the gain mismatch parameter g _a .

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (16), and the second additional RSB may be represented by a gain (g) and a phase (?) As shown in FIG. 4B A circle having a center (g _a , θ _a ) in the plane in which it is formed

).

&Quot; (16) &quot;

Referring to Figure 4b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection exists only _(g, θ) Only 1 dog on a plane (that is, sol _2).

The intersection point where the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the control unit 120 having the equations (4), (13), and (16)

이고, 제2 추가 RSB의 크기가 제1 추가 RSB의 크기보다 큰 경우에는

이 됨을 알 수 있으므로, 제어부(120)는 기준 RSB와 제1 추가 RSB를 통해 위상 에러 파라미터(θ_err)를 결정한 뒤, 제1 추가 RSB의 크기와 제2 추가 RSB의 크기 비교를 통해 게인 에러 파라미터(g_err)를 결정할 수도 있다.Alternatively, the intersection point at which the reference RSB, the first additional RSB, and the second additional RSB meet is determined by the controller 120 firstly receiving a phase error parameter (a combination of Equations 4 and 13) through the reference RSB and the first additional RSB 0 _err ) and then comparing the size of the first additional RSB with the size of the second additional RSB. More specifically, referring to FIG. 4B, if the size of the second additional RSB is smaller than the size of the first additional RSB

, And if the size of the second additional RSB is larger than the size of the first additional RSB

The control unit 120 determines the phase error parameter? _Err through the reference RSB and the first additional RSB and then determines the gain error parameter? _Err by comparing the size of the first additional RSB with the size of the second additional RSB. (g _err ) may be determined.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

&Lt; Third Embodiment >

5A is _a diagram illustrating a first additional RSB measured when _a gain mismatch parameter g _a is input to _a digital baseband.

In order to determine the direct conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err), the controller 120 may enter the gain mismatch parameter (g _a) in a digital baseband, At this time, the RSB measuring unit 110 may measure the RSB of the signal output from the direct conversion transmitter 1 as the first additional RSB according to the input of the gain mismatch parameter g _a .

)으로 나타나게 된다.The first additional RSB may be expressed as Equation (17), and the scheme of the first additional RSB may be represented by a gain g and a phase &amp;thetas; A circle centered at (g _a , 0) in the plane in which it is formed

).

&Quot; (17) &quot;

Referring to FIG. 5A, it can be seen that there are two intersections (ie, sol ₁ and sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet, and the reference RSB and the first additional RSB Can be obtained by solving the equations (4) and (17) together.

However, this intersection point is based RSB and first additional RSB met _(g, θ), if present on a plane only 1 there can be, in this case corresponding to the intersection points, without having to measure the second additional RSB below The parameter can be determined by the gain error parameter g _err and the phase error parameter? _Err of the direct conversion transmitter 1.

However, as shown in FIG. 5A, when there are two intersection points between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), it is determined which one of the two intersections is the gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

5B is _a diagram exemplarily showing a second additional RSB measured when _a phase mismatch parameter? _A is input to _a digital baseband instead of the gain mismatch parameter ga, wherein _a reference RSB and a first additional RSB between the two gains of the direct conversion transmitter (1) in the intersection between the error parameter (g _err) and the phase error parameter gain mismatch parameter, to determine the intersection point corresponding to (θ _err), the control part 120 to a digital baseband ( g _a), instead it is possible to input the phase mismatch parameter (θ _a), thus RSB measuring section 110 outputted from the direct conversion transmitter (1) according to the input of the matching parameter (θ _a) the phase Miss The RSB of the signal can be measured as the second additional RSB.

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (18), and the second RSB scheme may be expressed as gain (g) and phase (?) As shown in FIG. 5B (0,? _A ) in the plane that is formed

).

&Quot; (18) &quot;

Referring to Figure 5b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection exists only _(g, θ) Only 1 dog on a plane (that is, sol _1).

The intersection at which the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the control unit 120 having the equations (4), (17), and (18) together.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

<Fourth Embodiment>

6A is _a diagram illustrating a first additional RSB measured when _a phase mismatch parameter? _A is input to _a digital baseband.

In order to determine the direct conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err), the controller 120 may enter a phase mismatch parameter (θ _a) in a digital baseband, At this time, the RSB measuring unit 110 may measure the RSB of the signal output from the direct conversion transmitter 1 as the first additional RSB according to the input of the phase mismatch parameter θ _a .

)으로 나타나게 된다.The first additional RSB may be expressed as Equation (19), and the scheme of the first additional RSB may be represented by a gain (g) and a phase (?) As shown in FIG. 6A (0,? _A ) in the plane that is formed

).

&Quot; (19) &quot;

Referring to FIG. 6A, it can be seen that there are two intersections (ie, sol ₁ and sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet, and the reference RSB and the first additional RSB Can be found by solving the equations (4) and (19) together.

However, this intersection point is based RSB and first additional RSB met _(g, θ), if present on a plane only 1 there can be, in this case corresponding to the intersection points, without having to measure the second additional RSB below The parameter can be determined by the gain error parameter g _err and the phase error parameter? _Err of the direct conversion transmitter 1.

However, as shown in FIG. 6A, when there are two intersections between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), which of the two intersecting points is the gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

6B is _a diagram exemplarily showing a second additional RSB measured when _a gain mismatch parameter g _a is input to _a digital baseband instead of the phase mismatch parameter θ _a , In order to determine the intersection corresponding to the gain error parameter g _err and the phase error parameter? _Err of the direct conversion transmitter 1 among the two intersections between the RSBs, the control unit 120 sets the phase mismatch parameter (θ _a), instead it is possible to input the gain mismatch parameter (g _a), thus RSB measuring section 110 outputted from the direct conversion transmitter (1) according to the input of the gain mismatch parameter (g _a) Can be measured as the second additional RSB.

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (20), and the second additional RSB may be represented by a gain (g) and a phase (?) As shown in FIG. 6B A circle centered at (g _a , 0) in the plane in which it is formed

).

&Quot; (20) &quot;

Referring to Figure 6b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection is _(g, θ) Only 1 dog on a plane (that is, sol ₂₎ only exists.

The intersection at which the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the control unit 120 receiving the equations (4), (19), and (20) together.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

<Fifth Embodiment>

7A is _a diagram exemplifying a first additional RSB measured when _a gain mismatch parameter g _a and a phase mismatch parameter _a are input to _a digital baseband.

In order to determine the gain error parameter (g _err) and the phase error parameter (θ _err) of the direct conversion transmitter (1), the control unit 120 the gain mismatch parameter to a digital baseband (g _a) and the phase mismatch parameter ( θ _a) a can be input at the same time, this time RSB measuring section 110 outputted from the direct conversion transmitter (1) according to the input of the gain mismatch parameter (g _a) and the phase mismatch parameter (θ _a) The RSB of the signal can be measured as the first additional RSB.

)으로 나타나게 된다.The first additional RSB may be expressed by the following Equation (21), and the scheme of the first additional RSB may be represented by a gain g and a phase &amp;thetas; A circle having a center (g _a , θ _a ) in the plane in which it is formed

).

&Quot; (21) &quot;

Referring to FIG. 7A, it can be seen that there are two intersections (ie, sol ₁ and sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet, and the reference RSB and the first additional RSB Can be found by solving the equations (4) and (21) together.

However, this intersection point is based RSB and first additional RSB met _(g, θ), if present on a plane only 1 there can be, in this case corresponding to the intersection points, without having to measure the second additional RSB below The parameter can be determined by the gain error parameter g _err and the phase error parameter? _Err of the direct conversion transmitter 1.

However, as shown in FIG. 7A, when there are two intersection points between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), which of the two intersection points is the gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

7B is _a diagram exemplarily showing a second additional RSB measured when the phase mismatch parameter? _A is removed from the digital baseband so that only the gain mismatch parameter g _a is input to the digital baseband, for reference RSB and first additional RSB between 2 to determine the intersection direct gain error parameter (g _err) and the phase error parameter (θ _err) of the conversion transmitter (1) in the two cross point, the control part 120 is a digital base Only the gain mismatch parameter g _a can be input to the digital baseband by removing the phase mismatch parameter θ _{a in the} band. Accordingly, the RSB measurer 110 can calculate the gain mismatch parameter g _a , The RSB of the signal output from the direct conversion transmitter 1 can be measured as the second additional RSB.

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (22), and the second additional RSB may be represented by a gain (g) and a phase (?) As shown in FIG. 7B A circle having a center (g _a , 0) in the plane in which it is formed

).

&Quot; (22) &quot;

Referring to Figure 7b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection exists only _(g, θ) Only 1 dog on a plane (that is, sol _1).

The intersection at which the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the control unit 120 receiving the equations (4), (21), and (22) together.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

<Sixth Embodiment>

8A is _a diagram exemplarily showing a first additional RSB measured when _a gain mismatch parameter g _a and a phase mismatch parameter _a are input to _a digital baseband.

In order to determine the gain error parameter (g _err) and the phase error parameter (θ _err) of the direct conversion transmitter (1), the control unit 120 the gain mismatch parameter to a digital baseband (g _a) and the phase mismatch parameter ( θ _a) a can be input at the same time, this time RSB measuring section 110 outputted from the direct conversion transmitter (1) according to the input of the gain mismatch parameter (g _a) and the phase mismatch parameter (θ _a) The RSB of the signal can be measured as the first additional RSB.

)으로 나타나게 된다.The first additional RSB may be expressed as Equation (23), and the scheme of the first additional RSB may be represented by a gain g and a phase &amp;thetas; A circle having a center (g _a , θ _a ) in the plane in which it is formed

).

&Quot; (23) &quot;

Referring to FIG. 8A, it can be seen that there are two intersections (ie, sol ₁ and sol ₂ ) on the (g _, θ) plane where the reference RSB and the first additional RSB meet, and the reference RSB and the first additional RSB Can be found by solving the equations (4) and (23) together.

However, this intersection point is based RSB and first additional RSB met _(g, θ), if present on a plane only 1 there can be, in this case corresponding to the intersection points, without having to measure the second additional RSB below The parameter can be determined by the gain error parameter g _err and the phase error parameter? _Err of the direct conversion transmitter 1.

However, as shown in FIG. 8A, when there are two intersections between the reference RSB and the first additional RSB (i.e., sol ₁ and sol ₂ ), which of the two intersections is directly connected to the gain of the direct conversion transmitter 1 It is necessary to determine whether it corresponds to the error parameter g _err and the phase error parameter? _Err .

8B is _a diagram exemplarily showing a second additional RSB measured when the gain mismatch parameter g _a is removed from the digital baseband so that only the phase mismatch parameter? _A is input to the digital baseband, for reference RSB and first additional RSB between 2 to determine the intersection direct gain error parameter (g _err) and the phase error parameter (θ _err) of the conversion transmitter (1) in the two cross point, the control part 120 is a digital base The gain mismatch parameter g _a may be removed from the band so that only the phase mismatch parameter θ _a may be input to the digital baseband so that the RSB measurer 110 calculates the phase mismatch parameter θ _a , The RSB of the signal output from the direct conversion transmitter 1 can be measured as the second additional RSB.

)으로 나타나게 된다.The second additional RSB may be expressed as Equation (24), and the second additional RSB may be represented by a gain g and a phase &amp;thetas; (0,? _A ) in the plane that is formed

).

&Quot; (24) &quot;

Referring to Figure 8b, it can be seen that the reference RSB, RSB first additional and second additional RSB meet intersection exists only _(g, θ) Only 1 dog on a plane (that is, sol _1).

The intersection at which the reference RSB, the first additional RSB, and the second additional RSB meet can be known by the control unit 120 receiving the equations (4), (23), and (24) together.

That is, the control unit 120 determines the gain error parameter g _err and the phase error parameter? _{Err of} the direct conversion transmitter 1 using the reference RSB and the first additional RSB when present RSB intersection is only one inter), wherein the reference RSB, the first additional RSB and second additional RSB conversion transmitter (1) the gain error parameter (g _err) and the phase error parameter (θ _err of directly using a) the (If there are two intersections between the reference RSB and the first additional RSB).

9 is a flowchart of an I / Q imbalance compensation method of a direct conversion transmitter according to an embodiment of the present invention. Referring to FIG. 9, the I / Q imbalance compensation method of the direct conversion transmitter 1 according to an embodiment of the present invention will be described below. A method of compensating the Q imbalance will be described.

The I / Q imbalance compensation method of the direct conversion transmitter 1 according to an embodiment of the present invention is configured such that the RSB measurement unit 110 receives the digital baseband in-phase signal I _D input to the direct conversion transmitter 1, And a digital baseband quadrature-phase signal (Q _D ), a reference RSB measurement step of measuring the RSB of the signal output from the direct conversion transmitter 1 as a reference RSB is performed (S100).

Next, a gain mismatch parameter g _a or a phase mismatch parameter _{a a} is input to the digital baseband, and an RSB corresponding to the gain mismatch parameter g _a or the phase mismatch parameter _{a is} calculated An additional RSB measurement step is performed to measure as an additional RSB (S200).

The input of the gain mismatch parameter g _a or the phase mismatch parameter? _A for the digital baseband can be performed by the control unit 120. The reason that the controller 120 inputs the gain mismatch parameter g _a or the phase mismatch parameter? _A to the digital baseband is that the controller 120 sets the gain mismatch parameter g _a to the digital baseband, Or inputting only the phase mismatch parameter? _A , or inputting both the gain mismatch parameter g _a and the phase mismatch parameter? _A at the same time. And the measurement of the RSB (i.e., the additional RSB) according to the gain mismatch parameter g _a or the phase mismatch parameter θ _a may be performed by the RSB measuring unit 110.

Next, an error parameter determination step of determining a gain error parameter g _err and a phase error parameter? _Err using the reference RSB and the additional RSB is performed by the controller 120 (S300).

를 입력(즉, 게인 미스매치 파라미터로서

을 입력하고, 위상 미스매치 파라미터로서

을 입력)함으로써 직접 변환 송신기의 I/Q 불균형을 보상할 수 있다.Finally, the control unit 120 inputs the gain error parameter g _err and the inverse compensation value of the phase error parameter? _Err to the digital baseband to calculate I / Q imbalance compensation step (S400). More specifically, the control unit 120 controls the digital baseband

(I.e., as a gain mismatch parameter

As a phase mismatch parameter,

The I / Q imbalance of the direct conversion transmitter can be compensated.

In the I / Q imbalance compensation method of the direct conversion transmitter according to the present invention, the additional RSB measurement step may be performed by the first to sixth embodiments described above.

In the additional RSB measurement step according to the first embodiment, the gain mismatch parameter g _a is input to the digital baseband, and the RSB of the signal output from the direct conversion transmitter 1 is added to the first addition RSB, and input the phase mismatch parameter (? _A ) to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter (1) as a second additional RSB.

In the additional RSB measuring step according to the second embodiment, the phase mismatch parameter? _A is input to the digital baseband, the RSB of the signal output from the direct conversion transmitter 1 is measured as the first additional RSB, The gain mismatch parameter g _a may be further input to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter 1 as the second additional RSB.

In the additional RSB measurement step according to the third embodiment, the gain mismatch parameter g _a is input to the digital baseband, the RSB of the signal output from the direct conversion transmitter 1 is measured as the first additional RSB, The phase mismatch parameter? _A may be input to the digital baseband instead of the gain mismatch parameter g _a to measure the RSB of the signal output from the direct conversion transmitter 1 as a second additional RSB.

In the additional RSB measurement step according to the fourth embodiment, the phase mismatch parameter? _A is input to the digital baseband, the RSB of the signal output from the direct conversion transmitter 1 is measured as the first additional RSB, The gain mismatch parameter g _a may be input to the digital baseband instead of the phase mismatch parameter θ _a to measure the RSB of the signal output from the direct conversion transmitter 1 as a second additional RSB.

In the additional RSB measuring step according to the fifth embodiment, the gain mismatch parameter g _a and the phase mismatch parameter θ _a are input to the digital baseband, and the RSB of the signal output from the direct conversion transmitter 1 is set to A first additional RSB and removing the phase mismatch parameter θ _a from the digital baseband so that only the gain mismatch parameter g _a is input to the digital baseband, Can be measured as the second additional RSB.

Finally, in the additional RSB measurement step according to the sixth embodiment, the gain mismatch parameter g _a and the phase mismatch parameter? _A are input to the digital baseband, and the RSB of the signal output from the direct conversion transmitter is And the gain mismatch parameter g _a is removed from the digital baseband so that only the phase mismatch parameter? _A is input to the digital baseband, Can be measured as the second additional RSB.

After the additional RSB measurement step according to the above embodiments, the controller 120 uses the reference RSB, the first additional RSB, and the second additional RSB to calculate the gain error parameter g _err of the direct conversion transmitter 1 and the phase can determine the error parameter (θ _err), the I / Q imbalance of the gain error parameter (g _err) and the phase error parameter (θ _err) conversion transmitter (1) directly to station a compensation value by entering the digital base band You can compensate.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Of course, it is possible to modify it. Accordingly, it is intended that the technical scope of the present invention be defined only by the appended claims, and that all equivalent or equivalent variations thereof fall within the technical scope of the present invention.

1: direct conversion transmitter
11: first DAC 12: second DAC
21: first low-pass filter 22: second low-pass filter
31: first mixer 32: second mixer
40: local oscillator 50: adder
100: I / Q imbalance compensation device
110: RSB measuring unit 120:

Claims (14)

An apparatus for compensating an I / Q imbalance of a direct conversion transmitter,
(Residual Side-Band) of a signal output from the direct conversion transmitter is measured as a reference RSB for the in-phase signal I _D and the quadrature-phase signal Q _D of the digital baseband input to the direct conversion transmitter An RSB measuring unit; And
And a controller for inputting a gain mismatch parameter g _a or a phase mismatch parameter? _A to the digital baseband,
The RSB measuring unit measures the RSB of the signal output from the direct conversion transmitter as an additional RSB according to the gain mismatch parameter g _a or the phase mismatch parameter θ _a inputted to the digital baseband,
Wherein the controller the gain error parameter (g determine the gain error parameter (g _err) and the phase error parameter (θ _err) of the direct-conversion transmitter by using the reference RSB and the additional RSB measured in the RSB measuring unit, and _err ) and an inverse compensation value of a phase error parameter ( _err ) to the digital baseband to compensate the I / Q imbalance of the direct conversion transmitter.
The method according to claim 1,
Wherein the controller inputs _a gain mismatch parameter g _a to the digital baseband and the RSB measurer obtains RSB of a signal output from the direct conversion transmitter according to an input of the gain mismatch parameter g _a , Measured as an additional RSB,
The control unit may delete the RSB of the signal output from the direct conversion transmitter according to an input of the phase-mismatch parameter (θ _a) a further input, and the phase mismatch parameter (θ _a) the RSB measurement unit to the digital baseband 2 &lt; / RTI &gt; additional RSB,
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
The method according to claim 1,
Wherein the controller inputs _a phase mismatch parameter (θ _a ) to the digital baseband, and the RSB measurer obtains a RSB of a signal output from the direct conversion transmitter according to an input of the phase mismatch parameter (θ _a ) Measured as an additional RSB,
The control unit further inputs _a gain mismatch parameter g _a to the digital baseband, and the RSB measurer sets RSB of the signal output from the direct conversion transmitter in accordance with the input of the gain mismatch parameter g _a 2 &lt; / RTI &gt; additional RSB,
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
The method according to claim 1,
Wherein the controller inputs _a gain mismatch parameter g _a to the digital baseband and the RSB measurer obtains RSB of a signal output from the direct conversion transmitter according to an input of the gain mismatch parameter g _a , Measured as an additional RSB,
The control unit wherein the directly depending on the input of the gain mismatch parameter (g _a) instead of the phase mismatch parameter (θ _a) input, and the phase mismatch parameter (θ _a) the RSB measurement unit to the digital baseband, The RSB of the signal output from the conversion transmitter is measured as a second additional RSB,
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
The method according to claim 1,
Wherein the controller inputs _a phase mismatch parameter (θ _a ) to the digital baseband, and the RSB measurer obtains a RSB of a signal output from the direct conversion transmitter according to an input of the phase mismatch parameter (θ _a ) Measured as an additional RSB,
Wherein the controller inputs the gain mismatch parameter (g _a ) instead of the phase mismatch parameter (? _A ) to the digital baseband, and the RSB measurer obtains, based on the gain mismatch parameter (g _a ) The RSB of the signal output from the conversion transmitter is measured as a second additional RSB,
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
The method according to claim 1,
Wherein the controller inputs _a gain mismatch parameter g _a and a phase mismatch parameter θ _a to the digital baseband and the RSB measurer receives the gain mismatch parameter g _a and the phase mismatch parameter θ _a The RSB of the signal output from the direct conversion transmitter is measured as a first additional RSB,
Wherein the controller removes the phase mismatch parameter (? _A ) from the digital baseband so that only the gain mismatch parameter (g _a ) is input to the digital baseband, and the RSB measurer obtains the gain mismatch parameter the RSB of the signal output from the direct conversion transmitter is measured as a second additional RSB according to the input of _a )
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
The method according to claim 1,
Wherein the controller inputs _a gain mismatch parameter g _a and a phase mismatch parameter θ _a to the digital baseband and the RSB measurer receives the gain mismatch parameter g _a and the phase mismatch parameter θ _a The RSB of the signal output from the direct conversion transmitter is measured as a first additional RSB,
Wherein the controller removes the gain mismatch parameter g _a from the digital baseband so that only the phase mismatch parameter? _A is input to the digital baseband, and the RSB measurer obtains the phase mismatch parameter? the RSB of the signal output from the direct conversion transmitter is measured as a second additional RSB according to the input of _a )
The control unit the reference RSB, the first additional RSB and second add using the RSB gain error parameter (g _err) and the phase error parameter I / Q imbalance compensation in a direct conversion transmitter, characterized in that for determining a (θ _err) Device.
A method for compensating for I / Q imbalance of a direct conversion transmitter,
(RSB) of a signal output from the direct conversion transmitter to a reference RSB for a digital baseband in-phase signal (I _D ) and a digital baseband quadrature signal (Q _D ) input to the direct conversion transmitter, A reference RSB measuring step of measuring a reference RSB;
Gain mismatch parameters to the digital baseband (g _a) or the phase mismatch parameter (θ _a) to enter the said direct conversion transmitter according to the gain mismatch parameter (g _a) or the phase mismatch parameter (θ _a) An additional RSB measurement step of measuring the RSB of the signal output from the RSB as an additional RSB;
An error parameter determination step of determining a gain error parameter (g _err ) and a phase error parameter (? _Err ) of the direct conversion transmitter using the reference RSB and the additional RSB; And
And an I / Q imbalance compensation step of inputting the inverse compensation value of the gain error parameter g _err and the phase error parameter? _Err into the digital baseband to compensate the I / Q imbalance of the direct conversion transmitter I / Q imbalance compensation method of a direct conversion transmitter.
9. The method of claim 8,
In the additional RSB measuring step,
A gain mismatch parameter g _a is input to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter as a first additional RSB and a phase mismatch parameter θ _a to the digital baseband And measures the RSB of the signal output from the direct conversion transmitter as a second additional RSB,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.
9. The method of claim 8,
In the additional RSB measuring step,
A phase mismatch parameter? _A is input to the digital baseband to measure RSB of a signal output from the direct conversion transmitter as a first additional RSB, and a gain mismatch parameter g _a is further added to the digital baseband And measures the RSB of the signal output from the direct conversion transmitter as a second additional RSB,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.
9. The method of claim 8,
In the additional RSB measuring step,
A gain mismatch parameter g _a is input to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter as a first additional RSB, and the gain mismatch parameter g _a is substituted into the digital baseband The RSB of the signal output from the direct conversion transmitter is measured as a second additional RSB by inputting the phase mismatch parameter θ _a ,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.
9. The method of claim 8,
In the additional RSB measuring step,
A phase mismatch parameter? _A is input to the digital baseband to measure the RSB of the signal output from the direct conversion transmitter as a first additional RSB, and the phase mismatch parameter? _A is substituted into the digital baseband Inputting the gain mismatch parameter g _a to measure the RSB of the signal output from the direct conversion transmitter as a second additional RSB,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.
9. The method of claim 8,
In the additional RSB measuring step,
A gain mismatch parameter g _a and a phase mismatch parameter _a are input to the digital baseband to measure the RSB of a signal output from the direct conversion transmitter as a first additional RSB, The RSB of the signal output from the direct conversion transmitter is measured as the second additional RSB in a state where only the gain mismatch parameter g _a is input to the digital baseband by removing the phase mismatch parameter θ _a ,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.
9. The method of claim 8,
In the additional RSB measuring step,
A gain mismatch parameter g _a and a phase mismatch parameter _a are input to the digital baseband to measure the RSB of a signal output from the direct conversion transmitter as a first additional RSB, The RSB of the signal output from the direct conversion transmitter is measured as a second additional RSB in a state where only the phase mismatch parameter? _A is input to the digital baseband by removing the gain mismatch parameter g _a ,
In the error parameter determination step,
Wherein the gain error parameter g _err and the phase error parameter _err are determined using the reference RSB, the first additional RSB, and the second additional RSB.

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