Real-time calibration method and device for IQ imbalance of transmitting terminal

Abstract

The invention relates to a transmitting end IQ imbalance real-time calibration method and device, and the method comprises the steps: enabling a local oscillator module to reach a first phase and a second phase through two times of configuration of a delay adjustment module, and enabling the basic features of a transmitting channel signal obtained after two times of adjustment to be a first phase and a second phase, recording the data as a first basic feature and a second basic feature, and simultaneously obtaining corresponding first node data and second node data before compensation of a transmitting path and corresponding first node data and second node data after compensation of a feedback path; when the first basic feature is similar to the second basic feature, calculating a compensation coefficient of I / Q imbalance of a transmitting path and a compensation coefficient of I / Q imbalance of a feedback path; and adjusting the transmitting path compensation module and the feedback path compensation module according to the I / Q imbalance compensation coefficient of the transmitting path and the feedback path. According to the invention, the compensation effect can be improved by adopting relatively low hardware cost.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a method and device for real-time calibration of IQ imbalance at a transmitting end. Background Art

[0002] For zero-IF transmitters, since it is difficult for the I / Q local oscillators to be perfectly orthogonal, it is difficult for the analog filter characteristics (amplitude-frequency and phase-frequency responses) of the I / Q channels to be consistent. These two points are collectively referred to as the unbalanced characteristics of the I / Q channels. The unbalanced characteristics of the I / Q channels will cause the transmitter signal to generate a relatively large image, thereby deteriorating the EVM of the transmitter signal. Therefore, the correction of IQ imbalance is a problem that must be solved for zero-IF transmitters.

[0003] In the prior art, two methods, open-loop and closed-loop, are usually used to solve this problem. Among them, open-loop calibration is to use an instrument (spectrum analyzer or power meter) to complete the I / Q imbalance calibration of the zero intermediate frequency transmitter. This method requires the use of an instrument to complete the calibration, and its application scenario is limited to factory calibration. The characteristics of analog devices will change during use due to factors such as ambient temperature and device aging, and the factory calibration coefficients cannot be updated in real time, so the compensation effect will deteriorate. Closed-loop calibration uses the feedback channel to down-convert the RF signal at the transmitter to the baseband, and then completes the I / Q imbalance calibration of the zero intermediate frequency transmitter. Although this solution has a relatively good compensation effect, the disadvantage is that the hardware cost is very high. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method and device for real-time calibration of IQ imbalance at a transmitting end, which can improve the compensation effect with a relatively low hardware cost.

[0005] The technical solution adopted by the present invention to solve the technical problem is: to provide a real-time calibration method for IQ imbalance at a transmitting end, wherein both a transmitting path and a feedback path are zero intermediate frequency architectures, and the transmitting path and the feedback path share a local oscillator module, and a delay adjustment module is provided between the feedback path and the local oscillator module, specifically comprising the following steps:

[0006] Configuring the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a first phase phi1;

[0007] Obtain the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously obtain the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n), where n = 0, 1, 2, ..., N-1;

[0008] The delay adjustment module is configured so that the phase of the local oscillator module reaching the feedback path is a second phase phi2, wherein |phi1-phi2|≠0orπ;

[0009] Obtain the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously obtain the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n);

[0010] determining whether the first basic feature and the second basic feature are similar;

[0011] If the first basic feature is similar to the second basic feature, calculating a compensation coefficient for I / Q imbalance of a transmission path and a compensation coefficient for I / Q imbalance of a feedback path based on the first node data before compensation of the transmission path, the first node data after compensation of the feedback path, the second node data before compensation of the transmission path, and the second node data after compensation of the feedback path;

[0012] The compensation filter coefficient in the transmission path compensation module is adjusted according to the compensation coefficient of the I / Q imbalance of the transmission path, and the compensation filter coefficient in the feedback path compensation module is adjusted according to the compensation coefficient of the I / Q imbalance of the feedback path.

[0013] The calculating of the frequency domain compensation coefficient of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient of the I / Q imbalance of the feedback path based on the first node data before the transmission path compensation, the first node data after the feedback path compensation, the second node data before the transmission path compensation and the second node data after the feedback path compensation specifically includes:

[0014] According to the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n) constructing a first set of equations, and obtaining g1(n) and h1(n) in the time domain by solving the equations, and performing K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the first set of equations is:

[0015] is the adjoint matrix of x1(n);

[0016] According to the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2(n) construct a second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the second set of equations is:

[0017] is the adjoint matrix of x2(n);

[0018] pass Calculate the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path;

[0019] Perform fast Fourier transform on the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path, respectively, to obtain the I / Q imbalance compensation coefficient u(n) of the transmission path and the I / Q imbalance compensation coefficient v(n) of the feedback path.

[0020] The transmission path compensation module is implemented using four real filters, and the compensation filter coefficients of the four real filters in the transmission path compensation module are respectively: h 11 =-Re{u(n)},h 12 =-Im{u(n)},h 21 =-Im{u(n)}, h 22 =Re{u(n)} , where h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of the four real filters in the transmit path compensation module, u(n) is the transmit path I / Q imbalance compensation coefficient, Re{} represents the real part, and Im{} represents the imaginary part.

[0021] The feedback path compensation module is implemented using four real filters, and the compensation filter coefficients of the four real filters in the feedback path compensation module are: h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)}, wherein h1′1, h1′2, h2′1 and h2′2 are the compensation filter coefficients of the four real filters in the feedback path compensation module, respectively, and v(n) is the feedback path I / Q imbalance compensation coefficient.

[0022] The basic characteristics of the current transmission path signal include: the carrier type, carrier modulation mode and carrier average power of the signal.

[0023] The technical solution adopted by the present invention to solve the technical problem is: to provide a real-time calibration device for IQ imbalance at a transmitting end, wherein both a transmitting path and a feedback path are zero intermediate frequency architectures, and the transmitting path and the feedback path share a local oscillator module, and a delay adjustment module is arranged between the feedback path and the local oscillator module, including:

[0024] A first configuration module, configured to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a first phase phi1;

[0025] The first acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously acquire the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n), where n = 0, 1, 2, ..., N-1;

[0026] A second configuration module is used to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a second phase phi2, wherein |phi1-phi2|≠0orπ;

[0027] The second acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously acquire the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n);

[0028] A judging module, used for judging whether the first basic feature and the second basic feature are similar;

[0029] a calculation module, configured to calculate a compensation coefficient of I / Q imbalance of a transmission path and a compensation coefficient of I / Q imbalance of a feedback path based on first node data before compensation of the transmission path, first node data after compensation of the feedback path, second node data before compensation of the transmission path, and second node data after compensation of the feedback path when the first basic feature is similar to the second basic feature;

[0030] The adjustment module is used to adjust the compensation filter coefficient in the transmission path compensation module according to the compensation coefficient of the I / Q imbalance of the transmission path, and adjust the compensation filter coefficient in the feedback path compensation module according to the compensation coefficient of the I / Q imbalance of the feedback path.

[0031] The calculation module comprises:

[0032] The first constructing and solving unit is used to calculate the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation. com1 (n) constructing a first set of equations, and obtaining g1(n) and h1(n) in the time domain by solving the equations, and performing K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the first set of equations is: is the adjoint matrix of x1(n);

[0033] The second constructing and solving unit is used to calculate the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation. com2 (n) construct a second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the second set of equations is: is the adjoint matrix of x2(n);

[0034] The frequency domain compensation coefficient calculation unit is used to calculate the frequency domain compensation coefficient through Calculate the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path;

[0035] The transformation unit is used to perform fast Fourier transformation on the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path, respectively, to obtain the I / Q imbalance compensation coefficient u(n) of the transmission path and the I / Q imbalance compensation coefficient v(n) of the feedback path.

[0036] The transmission path compensation module is implemented using four real filters, and the adjustment module is implemented by h 11 = -Re{u(n)},h 12 = -Im{u(n)},h 21 = -Im{u(n)},h 22 = Re{u(n)} adjusts the compensation filter coefficients of the four real filters in the transmit path compensation module, where h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of the four real filters in the transmit path compensation module, u(n) is the transmit path I / Q imbalance compensation coefficient, Re{} represents the real part, and Im{} represents the imaginary part.

[0037] The feedback path compensation module is implemented using four real filters, and the adjustment module adjusts the compensation filter coefficients of the four real filters in the feedback path compensation module through h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)}, wherein h1′1, h1′2, h2′1 and h2′2 are the compensation filter coefficients of the four real filters in the feedback path compensation module respectively, and v(n) is the feedback path I / Q imbalance compensation coefficient.

[0038] The basic characteristics of the current transmission path signal acquired by the first acquisition module and the second acquisition module include: the carrier type, carrier modulation mode and carrier average power of the signal.

[0039] Beneficial Effects

[0040] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art: the present invention simultaneously considers the influence of I / Q imbalance of the transmission channel and the feedback channel, and calibrates the influence of I / Q imbalance of the transmission channel and the feedback channel in real time by using business signals, without sending additional training sequences to interrupt the business, and can track the performance changes caused by environmental factors such as the temperature of the module components. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 2 is a schematic diagram of an application system of a real-time calibration method for IQ imbalance at a transmitting end according to a first embodiment of the present invention;

[0042] Figure 2 is a flow chart of a method for real-time calibration of IQ imbalance at a transmitting end according to a first embodiment of the present invention;

[0043] Figure 3 is an implementation architecture diagram of a transmission path compensation module in a first embodiment of the present invention;

[0044] Figure 4 is a schematic diagram of the amplitude and phase response of the transmission channel in Example 1;

[0045] Figure 5 is a schematic diagram of the amplitude and phase response of the feedback channel in Example 1;

[0046] Figure 6 is a spectrum diagram before and after the transmission path compensation in Example 1;

[0047] Figure 7 is a spectrum diagram before and after feedback path compensation in Example 1;

[0048] Figure 8 is a schematic diagram of the amplitude and phase response of the transmit channel in Example 2;

[0049] Fig. 9 is a schematic diagram of the amplitude and phase response of the feedback channel in Example 2;

[0050] Fig.10 is a spectrum diagram before and after the transmission path compensation in Example 2;

[0051] Fig.11 1 is a spectrum diagram before and after feedback path compensation in Example 2. DETAILED DESCRIPTION

[0052] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0053] The first embodiment of the present invention relates to a real-time calibration method for IQ imbalance at a transmitting end, such as Figure 1 As shown, the internal transmission path and feedback path of the RF transceiver used in this method are both zero intermediate frequency architectures, and the transmission path and the feedback path share a local oscillator module 104. A delay adjustment module 105 is set between the feedback path and the local oscillator module, and the delay adjustment module 105 can adjust the phase of the local oscillator module 104 reaching the feedback path, which is used to distinguish the I / Q imbalance of the transmission path and the feedback path.

[0054] The basic principles for implementing this implementation are as follows:

[0055] The baseband complex signal at the transmitting end is denoted as x(n), the output after DAC and up-converter is denoted as y(n), and the influence caused by the non-ideal characteristics of the ABB filter module 102 and up-converter module 103 on the I / Q transmission path is denoted as g tx (n) and h tx (n), we can easily get formula (1):

[0056]

[0057] The output of y(n) after the downconverter and DAC is z(n). The effect of the non-ideal characteristics of the downconverter 106 and the ABB filter module 107 on the I / Q feedback path is represented by g. fb (n) and h fb (n), we can easily get formula (2):

[0058]

[0059] In formula (1) and (2), represents the convolution of two signals in the time domain. Substituting equation (1) into equation (2) yields the relationship between z(n) and x(n), as shown in equation (3):

[0060]

[0061] Transform equation (3) to the frequency domain through FFT to obtain equation (4):

[0062] Z(k)=G(k)X(k)+H(k)X * (k) (4)

[0063] Among them, G(k) and H(k) are both I / Q imbalance components that include both the transmission path and the feedback path, as shown in equation (5):

[0064]

[0065] Thus, the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path can be obtained:

[0066]

[0067] If we can obtain two sets of irrelevant G1(k) and H1(k), G2(k) and H2(k), and write them in matrix form as shown in equation (7), we can solve equation (7) by LS to obtain U(k) and V(k).

[0068]

[0069] like Figure 2 As shown, the real-time calibration method for IQ imbalance at the transmitting end of this embodiment includes the following steps:

[0070] Step 1, configuring the delay adjustment module 105 so that the phase of the local oscillator module 104 reaching the feedback path is a first phase phi1;

[0071] Step 2, obtain the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously obtain the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n), where n=0, 1, 2, ..., N-1; this step can be implemented by triggering the signal feature extraction module 109, and its specific implementation principle is as follows: the DFE entry DUC module 100 can obtain the carrier type, carrier modulation mode and carrier power information sent by the high-level in real time. This information is originally the information required by the transmitting DFE module to complete the cell establishment, transmission power control and digital pre-distortion module; there is a slot-level interrupt signal in the signal feature extraction module 109. Once the interrupt signal is triggered, the signal feature extraction module 109 can obtain the carrier type, carrier modulation mode and carrier average power of the signal sent in the current slot from the DUC module; while triggering the timing interrupt of the signal feature extraction module 109, it also triggers the capture module 200 of the transmission path and the capture module 201 of the feedback path to obtain the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n) to ensure that the currently acquired carrier information and the captured data are corresponding.

[0072] Step 3, configuring the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is the second phase phi2, where |phi1-phi2|≠0orπ;

[0073] Step 4, obtain the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously obtain the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n); The implementation method of this step is the same as step 2 and will not be repeated here.

[0074] Step 5, determine whether the first basic feature and the second basic feature are similar; if the first basic feature and the second basic feature are similar, proceed to step 6, otherwise, return to step 1.

[0075] Step 6: Based on the first node data x1(n) before the transmission path compensation and the first node data z1(n) after the feedback path compensation com1 (n), the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n) Calculate the compensation coefficient of the I / Q imbalance of the transmission path and the compensation coefficient of the I / Q imbalance of the feedback path. This step specifically includes the following sub-steps:

[0076] Step (a), based on the first node data x1(n) before the transmission path compensation and the first node data z1(n) after the feedback path compensation com1 (n) constructing a first set of equations, and obtaining g1(n) and h1(n) in the time domain by solving the equations, and performing K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the first set of equations is:

[0077] is the adjoint matrix of x1(n).

[0078] Step (b), according to the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n) construct a second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the second set of equations is:

[0079] is the adjoint matrix of x2(n).

[0080] Step (c), by The frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path are calculated.

[0081] Step (d) performs fast Fourier transform on the frequency domain compensation coefficient U(k) of the transmit path I / Q imbalance and the frequency domain compensation coefficient V(k) of the feedback path I / Q imbalance, respectively, to obtain the transmit path I / Q imbalance compensation coefficient u(n) and the feedback path I / Q imbalance compensation coefficient v(n).

[0082] Step 7: adjust the compensation filter coefficient in the transmission path compensation module according to the compensation coefficient of the transmission path I / Q imbalance, and adjust the compensation filter coefficient in the feedback path compensation module according to the compensation coefficient of the feedback path I / Q imbalance.

[0083] like Figure 3 As shown, the transmission path compensation module in this step is implemented using four real filters, and the compensation filter coefficients of the four real filters in the transmission path compensation module are respectively:

[0084] h 11 =-Re{u(n)},h 12 = -Im{u(n)},h 21 = -Im{u(n)},h 22 = Re{u(n)};

[0085] Among them, h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of four real filters in the transmission path compensation module, Re{} represents the real part, and Im{} represents the imaginary part.

[0086] The feedback path compensation module in this step has the same structure as the transmission path compensation module and is also implemented using four real filters. The compensation filter coefficients of the four real filters in the feedback path compensation module are:

[0087] h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)};

[0088] Among them, h1′1, h1′2, h2′1 and h2′2 are respectively the compensation filter coefficients of four real filters in the feedback path compensation module.

[0089] It is not difficult to find that the present invention takes into account the impact of I / Q imbalance of the transmission channel and the feedback channel at the same time, and calibrates the impact of I / Q imbalance of the transmission channel and the feedback channel in real time by using business signals, without sending additional training sequences to interrupt the business, and can track performance changes caused by environmental factors such as the temperature of module components.

[0090] Figure 1 Since it is difficult for the LOs of the IQ paths (modules 103_I and 103_Q) to be perfectly orthogonal, the amplitudes of the I / Q paths are inconsistent and the phases are not completely orthogonal. To verify the applicability of this implementation, the mathematical model of the transmission channel can be written as formula (8), where x com_I (n) and x com_Q (n) means Figure 1 The I / Q data output by the mid-baseband TXQEC compensation module 101, y I (n) and y Q (n) means Figure 1 Medium com_I (n) and x com_Q (n) Output after the quadrature modulator, ε tx Indicates the amplitude imbalance degree of the transmitter module 103_I and the module 103_Q, expressed as a percentage, φ tx The phase imbalance measurement between the transmitter module 103_I and the module 103_Q is expressed in radians. The low-pass filter of the transmitter I path (module 102_I) is represented by H filter_tx_I Indicates that the low-pass filter (module 102_Q) of the transmitter Q path is H filter_tx_Q express.

[0091]

[0092] The mathematical model of the feedback channel is shown in equation (9), where z I (n) and z Q (n) means Figure 1 middle y I (n) and y Q (n) Output after feedback quadrature demodulator, ε fb Indicates the amplitude imbalance degree of the feedback channel module 106_I and module 106_Q, expressed as a percentage, φ fb The phase imbalance measure of the feedback channel modules 106_I and 106_Q is expressed in radians. The low-pass filter (module 107_I) of feedback channel I is expressed in H filter_fb_I Indicates that the low-pass filter (module 107_Q) of the feedback channel Q is H filter_fb_Q express.

[0093]

[0094] The first adjustment value of the delay adjustment module 105 is recorded as φ1, and the second adjustment value is recorded as φ2, and the unit is radian.

[0095] Embodiment 1:

[0096] The parameters of this embodiment are as follows:

[0097] (1) Parameter ε of the mathematical model of the transmission channel tx =0.05,φ tx =0.05(rad),H filter_tx_I =[0.010.021-0.15

[0098] -0.02], H filter_tx_q =[0.02-0.0110.050.01];

[0099] (2) Parameter ε of the attribute model of the feedback channel fb =0.05,φ fb =0.05(rad),H filter_fb_I =[0.010.10.1-0.02], H filter_fb_q =[0.030.11-0.1-0.01];

[0100] (3) The first adjustment value of the delay adjustment module 105 is φ1=pi / 8, and the second adjustment value is φ2=13*pi / 7;

[0101] (4) The transmitter sends the NR 100M baseband signal, and the input sampling rate of the TX QEC compensation module 101 is 491.52Msps;

[0102] (5) The filter coefficient order of each real filter in the TXQEC compensation module 101 is K=11.

[0103] Figure 4 is a schematic diagram of the amplitude and phase response of the transmission channel in Example 1; Figure 5 is a schematic diagram of the amplitude and phase response of the feedback channel in Example 1; Figure 6 is a spectrum diagram before and after the transmission path compensation in Example 1; Figure 7 1 is a spectrum diagram before and after feedback path compensation in Example 1. It can be seen that this embodiment can complete the simultaneous calibration of I / Q imbalance of the transmission channel and the feedback channel.

[0104] Embodiment 2:

[0105] The parameters of this embodiment are as follows:

[0106] (1) Parameter ε of the mathematical model of the transmission channel tx=0.025,φ tx =0.025(rad),

[0107]

[0108] (2) Parameter ε of the attribute model of the feedback channel fb =0.025,φ fb =0.025(rad),

[0109]

[0110] (3) The first adjustment value of the delay adjustment module 105 is φ1=pi / 8, and the second adjustment value is φ2=19*pi / 7;

[0111] (4) The transmitter sends the NR 100M baseband signal, and the input sampling rate of the TX QEC compensation module 101 is 491.52Msps;

[0112] (5) The filter coefficient order of each real filter in the TXQEC compensation module 101 is K=32.

[0113] Figure 8 is a schematic diagram of the amplitude and phase response of the transmit channel in Example 2; Fig. 9 is a schematic diagram of the amplitude and phase response of the feedback channel in Example 2; Fig.10 is a spectrum diagram before and after the transmission path compensation in Example 2; Fig.11 1 is a spectrum diagram before and after feedback path compensation in Example 2. It can be seen that this embodiment can complete the simultaneous calibration of the I / Q imbalance of the transmission channel and the feedback channel.

[0114] The second embodiment of the present invention relates to a real-time calibration device for IQ imbalance at a transmitting end, wherein both a transmitting path and a feedback path are zero intermediate frequency architectures, and the transmitting path and the feedback path share a local oscillator module, and a delay adjustment module is provided between the feedback path and the local oscillator module, including:

[0115] A first configuration module, configured to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a first phase phi1;

[0116] The first acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously acquire the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n), where n = 0, 1, 2, ..., N-1;

[0117] A second configuration module is used to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a second phase phi2, wherein |phi1-phi2|≠0orπ;

[0118] The second acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously acquire the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n);

[0119] A judging module, used for judging whether the first basic feature and the second basic feature are similar;

[0120] a calculation module, configured to calculate a compensation coefficient of I / Q imbalance of a transmission path and a compensation coefficient of I / Q imbalance of a feedback path based on first node data before compensation of the transmission path, first node data after compensation of the feedback path, second node data before compensation of the transmission path, and second node data after compensation of the feedback path when the first basic feature is similar to the second basic feature;

[0121] The adjustment module is used to adjust the compensation filter coefficient in the transmission path compensation module according to the compensation coefficient of the I / Q imbalance of the transmission path, and adjust the compensation filter coefficient in the feedback path compensation module according to the compensation coefficient of the I / Q imbalance of the feedback path.

[0122] The calculation module comprises:

[0123] The first constructing and solving unit is used to calculate the first node data x1(n) before the transmission path is compensated and the first node data z after the feedback path is compensated. com1 (n) constructing a first set of equations, and obtaining g1(n) and h1(n) in the time domain by solving the equations, and performing K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the first set of equations is: is the adjoint matrix of x1(n);

[0124] The second constructing and solving unit is used to calculate the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation. com2 (n) construct a second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the second set of equations is: is the adjoint matrix of x2(n);

[0125] The frequency domain compensation coefficient calculation unit is used to calculate the frequency domain compensation coefficient through Calculate the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path;

[0126] The transformation unit is used to perform fast Fourier transformation on the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path, respectively, to obtain the I / Q imbalance compensation coefficient u(n) of the transmission path and the I / Q imbalance compensation coefficient v(n) of the feedback path.

[0127] The transmission path compensation module is implemented using four real filters, and the adjustment module is implemented by h 11 =-Re{u (n)},h 12 =-Im{u(n)},h 21 =-Im{u(n)},h 22 =Re{u(n)} The compensation filter coefficients of the four real filters in the transmit path compensation module are adjusted, where h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of the four real filters in the transmit path compensation module, u(n) is the transmit path I / Q imbalance compensation coefficient, Re{} represents the real part, and Im{} represents the imaginary part.

[0128] The feedback path compensation module is implemented using four real filters, and the adjustment module adjusts the compensation filter coefficients of the four real filters in the feedback path compensation module through h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)}, wherein h1′1, h1′2, h2′1 and h2′2 are the compensation filter coefficients of the four real filters in the feedback path compensation module respectively, and v(n) is the feedback path I / Q imbalance compensation coefficient.

[0129] The basic characteristics of the current transmission path signal acquired by the first acquisition module and the second acquisition module include: the carrier type, carrier modulation mode and carrier average power of the signal.

[0130] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0131] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0132] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction method, which is implemented in the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0133] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0134] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A real-time calibration method for IQ imbalance at a transmitting end, characterized in that: Both the transmitting path and the feedback path are zero intermediate frequency architectures, and the transmitting path and the feedback path share a local oscillator module, and a delay adjustment module is set between the feedback path and the local oscillator module, specifically including the following steps: Configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is the first phase phi1; obtain the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously obtain the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n), where n=0,1,2,…,N-1; The delay adjustment module is configured so that the phase of the local oscillator module reaching the feedback path is the second phase phi2, in, Obtain the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously obtain the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n); determining whether the first basic feature and the second basic feature are similar; If the first basic feature is similar to the second basic feature, calculating a compensation coefficient for I / Q imbalance of a transmission path and a compensation coefficient for I / Q imbalance of a feedback path based on the first node data before compensation of the transmission path, the first node data after compensation of the feedback path, the second node data before compensation of the transmission path, and the second node data after compensation of the feedback path; The compensation filter coefficient in the transmission path compensation module is adjusted according to the compensation coefficient of the I / Q imbalance of the transmission path, and the compensation filter coefficient in the feedback path compensation module is adjusted according to the compensation coefficient of the I / Q imbalance of the feedback path.

2. The real-time calibration method for IQ imbalance at the transmitting end according to claim 1, characterized in that: The calculating of the frequency domain compensation coefficient of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient of the I / Q imbalance of the feedback path based on the first node data before the transmission path compensation, the first node data after the feedback path compensation, the second node data before the transmission path compensation and the second node data after the feedback path compensation specifically includes: According to the first node data x1(n) before the transmission path compensation and the first node data z after the feedback path compensation com1 (n) constructing a first set of equations, and obtaining g1(n) and h1(n) in the time domain by solving the equations, and performing K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the first set of equations is: is the adjoint matrix of x1(n); According to the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation com2 (n) construct a second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the second set of equations is: is the adjoint matrix of x2(n); pass Calculate the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path; Perform fast Fourier transform on the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path, respectively, to obtain the I / Q imbalance compensation coefficient u(n) of the transmission path and the I / Q imbalance compensation coefficient v(n) of the feedback path.

3. The real-time calibration method for IQ imbalance at the transmitting end according to claim 1, characterized in that: The transmission path compensation module is implemented using four real filters, and the compensation filter coefficients of the four real filters in the transmission path compensation module are respectively: 11 =-Re{u(n)},h 12 = -Im{u(n)},h 21 = -Im{u(n)},h 22 = Re{u(n)}, where h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of the four real filters in the transmit path compensation module, u(n) is the transmit path I / Q imbalance compensation coefficient, Re{} represents the real part, and Im{} represents the imaginary part.

4. The real-time calibration method for IQ imbalance at the transmitting end according to claim 1, characterized in that: The feedback path compensation module is implemented using four real filters, and the compensation filter coefficients of the four real filters in the feedback path compensation module are: h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)}, wherein h1′1, h1′2, h2′1 and h2′2 are the compensation filter coefficients of the four real filters in the feedback path compensation module, respectively, and v(n) is the feedback path I / Q imbalance compensation coefficient.

5. The real-time calibration method for IQ imbalance at the transmitting end according to claim 1, characterized in that: The basic characteristics of the current transmission path signal include: the carrier type, carrier modulation mode and carrier average power of the signal.

6. A real-time calibration device for IQ imbalance at a transmitting end, characterized in that: Both the transmitting path and the feedback path are zero intermediate frequency architectures, and the transmitting path and the feedback path share a local oscillator module. A delay adjustment module is provided between the feedback path and the local oscillator module, including: A first configuration module, configured to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a first phase phi1; The first acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the first basic characteristics, and simultaneously acquire the first node data x1(n) before the transmission path compensation and the first node data x1(n) after the feedback path compensation. z com1 (n), where n = 0, 1, 2, ..., N-1; A second configuration module is used to configure the delay adjustment module so that the phase of the local oscillator module reaching the feedback path is a second phase phi2, wherein |phi1-phi2|≠0orπ; The second acquisition module is used to acquire the basic characteristics of the current transmission path signal, recorded as the second basic characteristics, and simultaneously acquire the second node data x2(n) before the transmission path compensation and the second node data x2(n) after the feedback path compensation. z com2 (n); A judging module, used for judging whether the first basic feature and the second basic feature are similar; a calculation module, configured to calculate a compensation coefficient of I / Q imbalance of a transmission path and a compensation coefficient of I / Q imbalance of a feedback path based on first node data before compensation of the transmission path, first node data after compensation of the feedback path, second node data before compensation of the transmission path, and second node data after compensation of the feedback path when the first basic feature is similar to the second basic feature; The adjustment module is used to adjust the compensation filter coefficient in the transmission path compensation module according to the compensation coefficient of the I / Q imbalance of the transmission path, and adjust the compensation filter coefficient in the feedback path compensation module according to the compensation coefficient of the I / Q imbalance of the feedback path.

7. The real-time calibration device for IQ imbalance at the transmitting end according to claim 6, characterized in that: The calculation module comprises: The first constructing and solving unit is used to calculate the first node data x1(n) before the transmission path is compensated and the first node data z after the feedback path is compensated. com1 (n) construct the first set of equations, and obtain g1(n) and h1(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g1(n) and h1(n) to obtain G1(k) and H1(k), respectively, wherein the The first set of equations is: is the adjoint matrix of x1(n); The second constructing and solving unit is used to calculate the second node data x2(n) before the transmission path compensation and the second node data z after the feedback path compensation. com2 (n) construct the second set of equations, and obtain g2(n) and h2(n) in the time domain by solving the equations, and perform K-point fast Fourier transform on g2(n) and h2(n) to obtain G2(k) and H2(k), respectively, wherein the The second set of equations is: is the adjoint matrix of x2(n); The frequency domain compensation coefficient calculation unit is used to calculate the frequency domain compensation coefficient through Calculate the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path; The transformation unit is used to perform fast Fourier transformation on the frequency domain compensation coefficient U(k) of the I / Q imbalance of the transmission path and the frequency domain compensation coefficient V(k) of the I / Q imbalance of the feedback path, respectively, to obtain the I / Q imbalance compensation coefficient u(n) of the transmission path and the I / Q imbalance compensation coefficient v(n) of the feedback path.

8. The real-time calibration device for IQ imbalance at the transmitting end according to claim 6, characterized in that: The transmission path compensation module is implemented using four real filters, and the adjustment module is implemented by h 11 =-Re{u(n)},h 12 = -Im{u(n)},h 21 = -Im{u(n)},h 22 = Re{u(n)} adjusts the compensation filter coefficients of the four real filters in the transmit path compensation module, where h 11 、h 12 、h 21 and h 22 They are the compensation filter coefficients of the four real filters in the transmit path compensation module, u(n) is the transmit path I / Q imbalance compensation coefficient, Re{} represents the real part, and Im{} represents the imaginary part.

9. The real-time calibration device for IQ imbalance at the transmitting end according to claim 6, characterized in that: The feedback path compensation module is implemented using four real filters, and the adjustment module adjusts the compensation filter coefficients of the four real filters in the feedback path compensation module through h1′1=Re{v(n)}, h1′2=Im{v(n)}, h2′1=Im{v(n)}, h2′2=-Re{v(n)}, wherein h1′1, h1′2, h2′1 and h2′2 are the compensation filter coefficients of the four real filters in the feedback path compensation module respectively, and v(n) is the feedback path I / Q imbalance compensation coefficient.

10. The real-time calibration device for IQ imbalance at the transmitting end according to claim 6, characterized in that: The basic characteristics of the current transmission path signal acquired by the first acquisition module and the second acquisition module include: the carrier type, carrier modulation mode and carrier average power of the signal.

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