Local oscillator phase adjustment circuit, calibration method and device in radio frequency receiver

Abstract

The present application relates to a local oscillator phase adjustment circuit, calibration method, and device in a radio frequency receiver. The local oscillator phase adjustment circuit includes an inverting module and a first phase adjustment module. The inverting module is used to generate a second local oscillator signal from a first local oscillator signal. After receiving a current fine-tuning signal, the first phase adjustment module can control the delay between the first local oscillator signal and the second local oscillator signal via the second and third input terminals of the inverting module, respectively, thereby adjusting the phase of the second local oscillator signal in the orthogonal channel or the in-phase channel in the orthogonal demodulation method, thereby solving the phase mismatch problem of the local oscillator signal during the orthogonal demodulation process.

Description

Technical Field

[0001] The present application relates to the technical field of receivers, and in particular to a local oscillator phase adjustment circuit, calibration method, and device in a radio frequency receiver. Background Art

[0002] IQ modulation (In-Phase and Quadrature Modulation) uses two orthogonal carrier signals to carry information. Ideally, the I and Q signals should have the same amplitude and be strictly orthogonal. However, due to hardware differences, environmental interference, and other factors in actual systems, the I and Q signals often exhibit amplitude and phase imbalances, known as IQ mismatch. IQ mismatch exists in both the local oscillator (LO) and baseband signals. Mismatch calibration typically involves pre-distortion calibration of both the LO and baseband signals in the digital domain. However, this approach does not provide high LO calibration accuracy. Summary of the Invention

[0003] Based on this, it is necessary to provide a local oscillator phase adjustment circuit, calibration method and device in a radio frequency receiver.

[0004] In a first aspect, the present application provides a local oscillator phase adjustment circuit, comprising:

[0005] an inverting module, comprising a first input terminal, a second input terminal, a third input terminal and an output terminal, configured to receive a first local oscillation signal through the first input terminal and output a second local oscillation signal through the output terminal;

[0006] A first phase adjustment module is connected to the second input terminal and the third input terminal of the inverting module, and is used to control the delay duration between the first local oscillator signal and the second local oscillator signal according to the received current fine-tuning signal; wherein the phase difference between the first local oscillator signal and the second local oscillator signal is related to the delay duration.

[0007] In one embodiment, the first phase adjustment module includes:

[0008] a first phase adjustment module, connected to the second input terminal of the inverting module, configured to receive a current fine-tuning signal and, when the first local oscillation signal is a rising edge signal, control a delay time between the first local oscillation signal and the second local oscillation signal;

[0009] The second phase adjustment module is connected to the third input end of the inverting module, and is used to receive the current fine-tuning signal, and when the first local oscillation signal is a falling edge signal, control the delay time between the first local oscillation signal and the second local oscillation signal.

[0010] In one embodiment, the first phase adjustment module and the second phase adjustment module both include:

[0011] a current source array, configured to receive the current fine-tuning signal and output a first conduction current according to the current fine-tuning signal;

[0012] a first transistor, wherein a gate of the first transistor is connected to the current source array, a first electrode of the first transistor is connected to a target power supply, a second electrode of the first transistor is connected to a target input terminal of the inverting module, and a turn-on delay duration of the first transistor is related to the first turn-on current;

[0013] In the first phase adjustment module, the target power supply is a working power supply, and the target input end is the second input end;

[0014] In the second phase adjustment module, the target power source is a common ground, and the target input terminal is the third input terminal.

[0015] In one embodiment, the inversion module includes two inverters, and the connection point of the two inverters serves as an intermediate node; the signal of the intermediate node is opposite in phase to the first local oscillator signal and the second local oscillator signal respectively;

[0016] The local oscillator phase adjustment circuit also includes:

[0017] The second phase adjustment module is respectively connected to the first input end, the intermediate node and the output end of the inverting module, and is used to control the level flip delay time of the signal of the intermediate node according to the received first power supply signal, the second power supply signal, the first local oscillator signal and the second local oscillator signal.

[0018] In one embodiment, the second phase adjustment module includes:

[0019] a third phase adjustment module, connected to the first input end, the intermediate node, and the output end, respectively, for controlling a level flip delay duration of a signal at the intermediate node according to the first power supply signal, the first local oscillator signal, and the second local oscillator signal;

[0020] The fourth phase adjustment module is respectively connected to the first input end, the intermediate node, and the output end, and is used to control the level flip delay length of the signal of the intermediate node according to the second power supply signal, the first local oscillator signal, and the second local oscillator signal.

[0021] In a second aspect, the present application further provides a local oscillator phase calibration device, comprising:

[0022] The local oscillator phase adjustment circuit provided by any of the above embodiments;

[0023] A local oscillator phase calibration circuit is connected to the local oscillator phase adjustment circuit, and is used to obtain an orthogonal baseband signal and an in-phase baseband signal, determine a current fine-tuning signal according to the orthogonal baseband signal and the in-phase baseband signal, and send the current fine-tuning signal to the local oscillator phase adjustment circuit.

[0024] In a third aspect, the present application further provides a radio frequency receiver, comprising:

[0025] A local oscillator signal generating circuit, configured to generate a first local oscillator signal;

[0026] The local oscillator phase calibration device provided in any of the above embodiments is connected to the local oscillator signal generating circuit, and is used to calibrate the first local oscillator signal into a second local oscillator signal;

[0027] a down-conversion mixer, connected to the local oscillator phase calibration device, configured to mix the second local oscillator signal with the radio frequency signal to generate an orthogonal demodulation signal and an in-phase demodulation signal;

[0028] The baseband filter is connected to the down-conversion mixer and is used to filter the quadrature demodulation signal to generate a quadrature baseband signal; and to filter the in-phase demodulation signal to generate an in-phase baseband signal.

[0029] In a fourth aspect, the present application further provides a local oscillator phase calibration method, which is applied to the local oscillator phase calibration device provided in any of the above embodiments, and the method includes:

[0030] Obtaining a quadrature baseband signal and an in-phase baseband signal;

[0031] determining a current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal;

[0032] According to the current fine-tuning signal, the delay duration between the first local oscillation signal and the second local oscillation signal is controlled; wherein the phase difference between the first local oscillation signal and the second local oscillation signal is related to the delay duration.

[0033] In one embodiment, determining the current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal includes:

[0034] Acquire a first orthogonal baseband signal and a first in-phase baseband signal corresponding to a first radio frequency signal; the first radio frequency signal has a different frequency from the first local oscillator signal;

[0035] Acquire a link gain and a baseband amplitude mismatch value according to the first orthogonal baseband signal and the first in-phase baseband signal;

[0036] Acquire a second orthogonal baseband signal and a second in-phase baseband signal corresponding to a second radio frequency signal, wherein the second radio frequency signal has the same frequency as the first local oscillator signal;

[0037] Acquire a phase of the second radio frequency signal according to the second orthogonal baseband signal and the link gain;

[0038] Obtaining a local oscillator phase mismatch value according to the phase of the second radio frequency signal, the link gain, the baseband amplitude mismatch value, and the second in-phase baseband signal;

[0039] The current fine-tuning signal is generated according to the local oscillator phase mismatch value.

[0040] In one embodiment, after controlling the delay between the first local oscillation signal and the second local oscillation signal according to the current fine-tuning signal, the method further includes:

[0041] Repeating the operation of obtaining a third quadrature baseband signal and a third in-phase baseband signal corresponding to the third RF signal, and obtaining a local oscillator phase mismatch value according to the third quadrature baseband signal, the third in-phase baseband signal, the link gain, and the baseband amplitude mismatch value until the local oscillator phase mismatch value has a different sign from the local oscillator phase mismatch value obtained previously;

[0042] The third radio frequency signal has the same frequency as the first local oscillator signal.

[0043] In the local oscillator phase adjustment circuit, calibration method, and device in the aforementioned radio frequency receiver, the local oscillator phase adjustment circuit includes an inverting module and a first phase adjustment module. The inverting module is used to generate a second local oscillator signal from a first local oscillator signal. Upon receiving a current fine-tuning signal, the first phase adjustment module controls the delay between the first and second local oscillator signals via the inverting module's second and third input terminals, respectively. This adjusts the phase of the second local oscillator signal in the quadrature channel or the in-phase channel in a quadrature demodulation scheme, ensuring that the local oscillator signals in the quadrature and in-phase channels remain consistent. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 A structural block diagram of a local oscillator phase adjustment circuit provided in one embodiment;

[0046] Figure 2A schematic diagram of the circuit structure of a local oscillator phase adjustment circuit provided in one embodiment;

[0047] Figure 3 A structural block diagram of a local oscillator phase calibration device provided in one embodiment;

[0048] Figure 4 A structural block diagram of a radio frequency receiver provided by an embodiment;

[0049] Figure 5 A schematic flow chart of a local oscillator phase calibration method provided in one embodiment;

[0050] Figure 6 A schematic diagram of a flow chart for determining a current fine-tuning signal based on a quadrature baseband signal and an in-phase baseband signal according to an embodiment;

[0051] Figure 7 A schematic flow chart of a local oscillator phase calibration method provided in another embodiment;

[0052] Figure 8 This is an internal block diagram of a controller provided by an embodiment. DETAILED DESCRIPTION

[0053] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0055] It will be understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor without departing from the scope of this application. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0056] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0057] It is understood that “at least one” refers to one or more, “a plurality” refers to two or more, and “at least a portion of an element” refers to a portion or all of an element.

[0058] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Furthermore, the term "and / or" as used in this specification includes any and all combinations of the relevant listed items.

[0059] In one embodiment, Figure 1 As shown, the present application provides a local oscillator phase adjustment circuit, including an inverting module 110 and a first phase adjustment module 120 .

[0060] The inverting module 110 includes a first input terminal, a second input terminal, a third input terminal, and an output terminal. The first phase adjustment module 120 is connected to the second input terminal and the third input terminal of the inverting module 110 .

[0061] The inverting module 110 can be configured to receive a first local oscillator signal through a first input terminal and output a second local oscillator signal through an output terminal. The first local oscillator signal can be an initial local oscillator signal of a quadrature channel or an in-phase channel generated by a phase-locked loop or a signal generator. The second local oscillator signal is the signal that is ultimately mixed with the RF signal received by the RF receiver. The first and second local oscillator signals are periodic signals with the same waveform, which can be a sine wave, a triangle wave, a square wave, or the like.

[0062] For example, Figure 2 As shown, the inverting module 110 may include a two-stage inverter composed of transistors M1-M4, wherein transistors M1 and M2 constitute a first-stage inverter, and transistors M3 and M4 constitute a second-stage inverter. Transistors M1 and M3 are P-type, and transistors M2 and M4 are N-type. The connection point of the two-stage inverter serves as an intermediate node A, and the signal at the intermediate node has a phase opposite to that of the first local oscillator signal and the second local oscillator signal, respectively.

[0063] The first phase adjustment module 120 can be used to control the delay between the first and second local oscillator signals based on the received current fine-tuning signal. The phase difference between the first and second local oscillator signals is related to the delay. The delay refers to the time required for the inverting module 110's output terminal to output the corresponding second local oscillator signal after the first input terminal of the inverting module 110 inputs the first local oscillator signal. The phase difference between the first and second local oscillator signals accumulates over the delay.

[0064] In the embodiment of the present application, the local oscillator phase adjustment circuit includes an inverting module 110 and a first phase adjustment module 120. The inverting module 110 is used to generate a second local oscillator signal from a first local oscillator signal. After receiving the current fine-tuning signal, the first phase adjustment module 120 can control the delay between the first local oscillator signal and the second local oscillator signal through the second input terminal and the third input terminal of the inverting module 110, respectively, thereby adjusting the phase of the local oscillator signal of the orthogonal channel or the in-phase channel in the orthogonal demodulation method, so that the local oscillator signals of the orthogonal channel and the in-phase channel remain consistent.

[0065] In one embodiment, Figure 2 As shown, the first phase adjustment module 120 includes a first phase adjustment module 121 and a second phase adjustment module 122 .

[0066] The first phase adjustment module 121 is connected to the second input terminal of the inverting module 110 , and the second phase adjustment module 122 is connected to the third input terminal of the inverting module 110 .

[0067] The first phase adjustment module 121 is configured to receive a current fine-tuning signal and, when the first local oscillation signal is a rising edge signal, control a delay time between the first local oscillation signal and the second local oscillation signal.

[0068] The second phase adjustment module 122 is configured to receive the current fine-tuning signal and, when the first local oscillation signal is a falling edge signal, control the delay between the first local oscillation signal and the second local oscillation signal.

[0069] Specifically, the first phase adjustment module 121 and the second phase adjustment module 122 each include a current source array and a first transistor (ie Figure 2 transistors M5 and M6 in FIG).

[0070] The current source array can be used to receive a current fine-tuning signal and output a first conduction current according to the current fine-tuning signal.

[0071] The gate of the first transistor is connected to the current source array, the first electrode of the first transistor is connected to the target power supply, and the second electrode of the first transistor is connected to the target input terminal of the inverter module 110. The turn-on delay duration of the first transistor is related to the first turn-on current. The turn-on delay duration represents the time required for the first transistor to fully turn on from the off state. The smaller the first turn-on current, the longer the turn-on delay duration of the first transistor.

[0072] In the first phase adjustment module 121 , the target power source is the working power source, and the target input end is the second input end.

[0073] In the second phase adjustment module 122 , the target power source is the common ground, and the target input terminal is the third input terminal.

[0074] It is understandable that Figure 2 As shown, the first phase adjustment module 121 includes a current source array I_trim_P and a transistor M5. The second phase adjustment module 122 includes a current source array I_trim_N and a transistor M6. The current source array I_trim_P and the current source array I_trim_N each include multiple current sources connected in series. The transistor M5 is N-type, and the transistor M6 is P-type.

[0075] The working principle of the local oscillator phase adjustment circuit is as follows: when the first local oscillator signal is a rising edge signal, the transistor M1 is turned off and the transistor M2 is quickly turned on. The magnitude of the first on-current generated by the current source array I_trim_N is controlled by the current trimming signal, thereby controlling the on-delay time of the transistor M6. After the transistor M6 is turned on, the potential of the intermediate node A begins to flip from a high level to a low level. When the voltage of the intermediate node A drops to the on-voltage of the transistor M3, the transistor M3 is quickly turned on and the transistor M4 is turned off. The second local oscillator signal changes from a low level to a low level. When the first local oscillator signal is a falling edge signal, transistor M2 is turned off and transistor M1 is quickly turned on. The current trimming signal controls the magnitude of the first on-current generated by the current source array I_trim_P, thereby controlling the on-delay duration of transistor M5. After transistor M5 is turned on, the potential of the intermediate node A flips from a low level to a high level. After the voltage at the intermediate node A rises to the on-voltage of transistor M4, transistor M4 is quickly turned on, transistor M3 is turned off, and the second local oscillator signal flips from a high level to a low level. When the current source arrays I_trim_N and I_trim_P receive the same current trimming signal, the magnitude of the first on-current generated by the current source array I_trim_N is the same as the first on-current generated by the current source array I_trim_P, i.e., the on-delay durations of transistors M5 and M6 are the same.

[0076] In some embodiments, Figure 2As shown, both the first phase adjustment module 121 and the second phase adjustment module 122 further include a filter unit, wherein a first end of the filter unit is connected to the current source array, a second end of the filter unit is connected to the gate of the first transistor, and a third end of the filter unit is connected to the first electrode of the first transistor. The filter unit can improve the stability of the first conduction current. Specifically, in the first phase adjustment module 121, resistor R1 and capacitor C1 constitute the filter unit, and in the second phase adjustment module 122, resistor R2 and capacitor C2 constitute the filter unit.

[0077] In one embodiment, Figure 2 As shown, the local oscillator phase adjustment circuit further includes a second phase adjustment module 130. The second phase adjustment module 130 is connected to the first input terminal, the intermediate node, and the output terminal of the inverting module 110, respectively. The second phase adjustment module 130 is configured to control the level-flipping delay of the signal at the intermediate node based on the received first power signal, the second power signal, the first local oscillator signal, and the second local oscillator signal. The level-flipping delay represents the time required for the signal at the intermediate node to flip from a low level to a high level, or vice versa.

[0078] Specifically, if Figure 2 As shown, the second phase adjustment module 130 includes a third phase adjustment module 131 and a fourth phase adjustment module 132 .

[0079] The third phase adjustment module 131 is connected to the first input terminal, the intermediate node, and the output terminal, respectively, and can be used to control the level flip delay duration of the signal at the intermediate node based on the first power supply signal, the first local oscillator signal, and the second local oscillator signal. The third phase adjustment module 131 includes a transistor M7 and a transistor M8. The gate of transistor M7 is connected to the first input terminal of the inverting module 110, and the gate of transistor M8 is connected to the output terminal of the inverting module 110. Both transistors M7 and M8 are P-type.

[0080] The fourth phase adjustment module 132 is connected to the first input terminal, the intermediate node, and the output terminal, respectively, and can be used to control the level flip delay of the signal at the intermediate node based on the second power supply signal, the first local oscillator signal, and the second local oscillator signal. The third phase adjustment module 131 includes transistors M9 and M10. The gate of transistor M10 is connected to the first input terminal of the inverting module 110, and the gate of transistor M9 is connected to the output terminal of the inverting module 110. Transistors M9 and M10 are N-type.

[0081] The operating principle of the second phase adjustment module 130 is as follows: when the first local oscillator signal is a rising edge signal, transistor M10 is turned on. Since the second local oscillator signal is initially at a low level, transistor M9 is still in the off state. When the voltage of the second local oscillator signal rises to the turn-on voltage of transistor M9, transistor M9 is turned on, and the potential of the intermediate node A is quickly pulled down to zero, thereby shortening the level flip delay of the signal at the intermediate node. Similarly, when the first local oscillator signal is a falling edge signal, transistor M7 is turned on. Since the second local oscillator signal is initially at a high level, transistor M8 is still in the off state. When the voltage of the second local oscillator signal drops to the turn-on voltage of transistor M8, transistor M8 is quickly turned on, and the potential of the intermediate node A is quickly pulled up to the power supply voltage, thereby shortening the level flip delay of the signal at the intermediate node.

[0082] In this embodiment, by setting the second phase adjustment module 130 to accelerate the level flipping of the intermediate node signal when the level of the second local oscillator signal begins to flip, it can be ensured that the potential flipping of the intermediate node is completed within half a clock cycle. In addition, since the level of the second local oscillator signal begins to reverse only after the voltage of the intermediate node rises or falls to the turn-on voltage of the transistor in the second-stage inverter, therefore, by setting the second phase adjustment module 130 to accelerate the level flipping of the intermediate node signal when the level of the second local oscillator signal begins to flip, a larger adjustment range can be provided for the turn-on delay time of the first transistor, that is, the adjustment range of the delay time of the first local oscillator signal and the second local oscillator signal is increased, and the phase adjustment range of the local oscillator signal is increased.

[0083] In one embodiment, Figure 3 As shown, the present application also provides a local oscillator phase calibration device, including a local oscillator phase adjustment circuit 100 and a local oscillator phase calibration circuit 200.

[0084] Among them, the local oscillator phase calibration circuit 200 is connected to the local oscillator phase adjustment circuit 100, and can be used to obtain the orthogonal baseband signal and the in-phase baseband signal, determine the current fine-tuning signal according to the orthogonal baseband signal and the in-phase baseband signal, and send the current fine-tuning signal to the local oscillator phase adjustment circuit.

[0085] The local oscillator phase adjustment circuit 100 has been introduced in the above embodiment and will not be described again here.

[0086] In an embodiment of the present application, the local oscillator phase calibration device includes a local oscillator phase adjustment circuit 100 and a local oscillator phase calibration circuit 200. The local oscillator phase calibration circuit 200 determines the current fine-tuning signal according to the orthogonal baseband signal and the in-phase baseband signal, and the local oscillator phase adjustment circuit 100 adjusts the delay length of the first local oscillator signal and the second local oscillator signal, thereby realizing phase adjustment of the local oscillator signal of the orthogonal channel or the in-phase channel, so that the local oscillator signals of the orthogonal channel and the in-phase channel remain consistent.

[0087] In one embodiment, Figure 4 As shown, the present application also provides a radio frequency receiver, including a local oscillator signal generating circuit 20, a local oscillator phase calibration device 10, a down-conversion mixer 30, and a baseband filter 40. The local oscillator phase calibration device 20 is connected to the local oscillator signal generating circuit 10, the down-conversion mixer 30, and the baseband filter 40, respectively. The down-conversion mixer 30 is also connected to the baseband filter 40. More specifically, the local oscillator phase calibration circuit 200 is connected to the baseband filter 40, and the local oscillator phase adjustment circuit 100 is connected to the local oscillator signal generating circuit 20 and the down-conversion mixer 30, respectively.

[0088] The local oscillator signal generating circuit 20 can be used to generate a first local oscillator signal. The local oscillator signal generating circuit can be a phase-locked loop or a signal generator.

[0089] The local oscillator phase calibration device 10 may be used to calibrate a first local oscillator signal into a second local oscillator signal.

[0090] The down-conversion mixer 30 can be used to mix the second local oscillator signal with the radio frequency signal to generate an orthogonal demodulation signal and an in-phase demodulation signal. The radio frequency signal can be generated by a phase-locked loop circuit for calibration.

[0091] The baseband filter 40 may be configured to filter the quadrature demodulation signal to generate a quadrature baseband signal, and to filter the in-phase demodulation signal to generate an in-phase baseband signal.

[0092] In one embodiment, the RF receiver further includes an analog-to-digital converter, which is respectively connected to the baseband filter and the local oscillator signal calibration circuit and can be used to convert the orthogonal baseband signal and the in-phase baseband signal into digital signals and send them to the local oscillator signal calibration circuit.

[0093] In one embodiment, Figure 5 As shown, the present application also provides a local oscillator phase calibration method, which is applied to Figure 3 In the local oscillator phase calibration device shown, the local oscillator phase calibration method includes steps 502-506.

[0094] Step 502: Acquire a quadrature baseband signal and an in-phase baseband signal.

[0095] The local oscillator phase calibration circuit 200 can obtain a quadrature baseband signal and an in-phase baseband signal based on a baseband filter.

[0096] Step 504 : Determine a current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal.

[0097] The local oscillator phase calibration circuit 200 can determine the phase value of the local oscillator signal that needs to be compensated by analyzing and comparing the orthogonal baseband signal and the in-phase baseband signal, generate a current fine-tuning signal based on the phase value that needs to be compensated, and send the current fine-tuning signal to the local oscillator phase adjustment circuit 100.

[0098] Step 506: Control the delay time between the first local oscillation signal and the second local oscillation signal according to the current fine-tuning signal, wherein the phase difference between the first local oscillation signal and the second local oscillation signal is related to the delay time.

[0099] The local oscillator phase adjustment circuit 100 can control the delay duration between the first local oscillator signal and the second local oscillator signal according to the received current fine-tuning signal.

[0100] In an embodiment of the present application, by obtaining an orthogonal baseband signal and an in-phase baseband signal, a current fine-tuning signal is determined based on the orthogonal baseband signal and the in-phase baseband signal. Furthermore, based on the current fine-tuning signal, the delay duration between the first local oscillator signal and the second local oscillator signal is controlled, thereby achieving adjustment of the phase difference between the second local oscillator signal and the first local oscillator signal, thereby solving the problem of phase mismatch of the local oscillator signal.

[0101] In one embodiment, Figure 6 As shown, determining the current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal includes steps 602 to 612.

[0102] Step 602: Acquire a first quadrature baseband signal and a first in-phase baseband signal corresponding to a first radio frequency signal. The first radio frequency signal and the first local oscillator signal have different frequencies.

[0103] The first radio frequency signal can be generated by a calibration phase-locked loop circuit. The expression of the first radio frequency signal can be cos((ω LO +ω BB )t+φ1). Among them, ω LO is the angular frequency of the local oscillator signal, ω BB is the angular frequency of the baseband signal. Taking the signal of the orthogonal channel as the reference, after the first RF signal passes through the down-conversion mixer and the baseband filter, the first in-phase baseband signal obtained is RX_I1=G(1+a)cos(ω BB t+φ1-AB) / 2, the first orthogonal baseband signal can be expressed as RX_Q1=Gsin(ω BBt+φ1) / 2. Where G represents the link gain of the receiving channel, a represents the baseband amplitude mismatch between the first quadrature baseband signal and the first in-phase baseband signal, A represents the baseband phase mismatch between the first quadrature baseband signal and the first in-phase baseband signal, and B represents the local oscillator phase mismatch between the local oscillator signals of the quadrature channel and the in-phase channel.

[0104] Step 604 : Acquire a link gain and a baseband amplitude mismatch value according to the first quadrature baseband signal and the first in-phase baseband signal.

[0105] It is detected that the amplitude of the first in-phase baseband signal is m1 and the amplitude of the first quadrature baseband signal is n1. Then, let G(1+a) / 2=m1 and G / 2=n1 to obtain the link gain G and the baseband amplitude mismatch value a.

[0106] Step 606: Acquire a second orthogonal baseband signal and a second in-phase baseband signal corresponding to the second radio frequency signal; the second radio frequency signal has the same frequency as the first local oscillation signal.

[0107] Change the angular frequency of the radio frequency signal generated by the calibration phase-locked loop circuit, and let the second radio frequency signal be cos(ω LO t+φ1). Using the signal in the quadrature channel as a reference, the second RF signal, after passing through the down-conversion mixer and baseband filter, yields the second in-phase baseband signal RX_I2 = G(1+a)cos(φ2-B) / 2. The second quadrature baseband signal can be expressed as RX_Q2 = Gsin(φ2) / 2. Obviously, the second in-phase baseband signal and the second quadrature baseband signal are DC signals.

[0108] Step 608: Acquire the phase of the second radio frequency signal according to the second orthogonal baseband signal and the link gain.

[0109] The amplitude of the second orthogonal baseband signal is detected to be n2, and Gsin(φ2) / 2=n2 is set to obtain the phase φ2 of the second RF signal.

[0110] Step 610: Obtain a local oscillator phase mismatch value according to the phase, link gain, baseband amplitude mismatch value of the second RF signal and the second in-phase baseband signal.

[0111] The amplitude of the second in-phase baseband signal is detected to be m2. Let G(1+a)cos(φ2-B) / 2=m2. The local oscillator phase mismatch value B can be obtained based on the link gain G, baseband amplitude mismatch value a and phase φ2 of the second RF signal calculated previously.

[0112] Step 612: Generate a current fine-tuning signal according to the local oscillator phase mismatch value.

[0113] According to the direction of decreasing absolute value of the local oscillator phase mismatch value, the current fine-tuning signal is increased or decreased to adjust the phase of the local oscillator signal of the in-phase channel, so that the local oscillator signals of the quadrature channel and the in-phase channel are consistent.

[0114] Steps 602 to 612 can all be completed by the local oscillator phase calibration circuit 200 .

[0115] In one embodiment, Figure 7 As shown, after controlling the delay duration between the first local oscillator signal and the second local oscillator signal according to the current fine-tuning signal, it is necessary to repeatedly obtain the third orthogonal baseband signal and the third in-phase baseband signal corresponding to the third RF signal, and obtain the local oscillator phase mismatch value according to the third orthogonal baseband signal, the third in-phase baseband signal, the link gain, and the baseband amplitude mismatch value until the local oscillator phase mismatch value is inconsistent with the local oscillator phase mismatch value obtained previously.

[0116] The frequency of the third RF signal is the same as the first local oscillator signal. The expression of the third RF signal is cos(ω LO t+φ1). In practical applications, it is difficult to complete the phase adjustment of the in-phase channel local oscillator signal in a single pass based on the current fine-tuning signal generated by the local oscillator phase mismatch value. Therefore, the current fine-tuning signal can be increased or decreased by a preset value each time. Accordingly, it is necessary to repeatedly obtain the third orthogonal baseband signal and the third in-phase baseband signal corresponding to the third RF signal, and obtain the local oscillator phase mismatch value based on the third orthogonal baseband signal, the third in-phase baseband signal, the link gain, and the baseband amplitude mismatch value to obtain a new local oscillator phase mismatch value. This is done until the local oscillator phase mismatch value no longer has the same sign as the previously obtained local oscillator phase mismatch value, thereby determining that the phase calibration of the local oscillator signal is complete.

[0117] In some embodiments, to improve determination accuracy, the phase calibration of the local oscillator signal may be completed when two consecutive local oscillator phase mismatch values have different signs from the previous local oscillator phase mismatch value.

[0118] In one embodiment, after the local oscillator signal is calibrated using the local oscillator phase calibration method provided in any of the above embodiments, IQ mismatch calibration can also be performed on the baseband signal. The IQ mismatch between the quadrature baseband signal and the in-phase baseband signal includes baseband amplitude mismatch and baseband phase mismatch. Since the local oscillator signal has already been calibrated during baseband signal calibration, the local oscillator phase mismatch value B can be set to zero.

[0119] Specifically, a fourth in-phase baseband signal and a fourth quadrature baseband signal corresponding to the fourth RF signal can be obtained. The fourth in-phase baseband signal can be expressed as RX_I4=G(1+a)cos(ω BBt+φ3-A) / 2, the fourth orthogonal baseband signal can be expressed as RX_Q4=Gsin(ω BB t+φ3) / 2.

[0120] It is detected that the amplitude of the fourth in-phase baseband signal is m3, the amplitude of the fourth orthogonal baseband signal is n3, and the phase difference between the fourth in-phase baseband signal and the fourth orthogonal baseband signal is p1. Then, let G(1+a) / 2=m3, G / 2=n3, -A=-π / 2+p1, and the link gain G, baseband amplitude mismatch value a, and baseband phase mismatch value A can be obtained.

[0121] The IQ mismatch calibration of the baseband signal can be completed by compensating the quadrature baseband signal and the in-phase baseband signal of the receiving path according to the baseband phase mismatch value A and the baseband amplitude mismatch value a.

[0122] In an exemplary embodiment, a controller is provided, the internal structure of which can be shown as follows: Figure 8 As shown. The controller includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O) and a communication interface. The processor, memory and input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the controller is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the computer device is used to store data such as local oscillator phase mismatch value, baseband amplitude mismatch value, baseband phase mismatch value, link gain, etc. The input / output interface of the controller is used to exchange information between the processor and external devices. The communication interface of the controller is used to connect and communicate with external circuits. When the computer program is executed by the processor, a local oscillator phase calibration method is implemented.

[0123] In an exemplary embodiment, a controller is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the local oscillator phase calibration method provided in any of the above embodiments when executing the computer program.

[0124] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the local oscillator phase calibration method provided in any of the above embodiments is implemented.

[0125] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the local oscillator phase calibration method provided in any of the above embodiments is implemented.

[0126] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0127] In the description of this specification, reference to the terms "some embodiments" or "other embodiments" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0128] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A local oscillator phase adjustment circuit, characterized in that: include: an inverting module, comprising a first input terminal, a second input terminal, a third input terminal and an output terminal, configured to receive a first local oscillation signal through the first input terminal and output a second local oscillation signal through the output terminal; The first phase adjustment module includes a first phase adjustment module and a second phase adjustment module, wherein: The first phase adjustment module is connected to the second input end of the inverting module, and is used to receive a current fine-tuning signal, and when the first local oscillation signal is a rising edge signal, control the delay between the first local oscillation signal and the second local oscillation signal according to the current fine-tuning signal; The second phase adjustment module is connected to the third input end of the inverting module, and is used to receive the current fine-tuning signal, and when the first local oscillator signal is a falling edge signal, control the delay duration between the first local oscillator signal and the second local oscillator signal according to the current fine-tuning signal; wherein the phase difference between the first local oscillator signal and the second local oscillator signal is related to the delay duration.

2. The local oscillator phase adjustment circuit according to claim 1, characterized in that: The first phase adjustment module and the second phase adjustment module both include: a current source array, configured to receive the current fine-tuning signal and output a first conduction current according to the current fine-tuning signal; a first transistor, wherein a gate of the first transistor is connected to the current source array, a first electrode of the first transistor is connected to a target power supply, a second electrode of the first transistor is connected to a target input terminal of the inverting module, and a turn-on delay duration of the first transistor is related to the first turn-on current; In the first phase adjustment module, the target power supply is a working power supply, and the target input end is the second input end; In the second phase adjustment module, the target power source is a common ground, and the target input terminal is the third input terminal.

3. The local oscillator phase adjustment circuit according to claim 1, wherein: The inverting module includes two inverters, and the connection point of the two inverters serves as an intermediate node; the phase of the signal of the intermediate node is opposite to that of the first local oscillator signal and the second local oscillator signal respectively; The local oscillator phase adjustment circuit also includes: The second phase adjustment module is respectively connected to the first input end, the intermediate node and the output end of the inverting module, and is used to control the level flip delay time of the signal of the intermediate node according to the received first power supply signal, the second power supply signal, the first local oscillator signal and the second local oscillator signal.

4. The local oscillator phase adjustment circuit according to claim 3, characterized in that: The second phase adjustment module includes: a third phase adjustment module, connected to the first input end, the intermediate node, and the output end, respectively, for controlling a level flip delay duration of a signal at the intermediate node according to the first power supply signal, the first local oscillator signal, and the second local oscillator signal; The fourth phase adjustment module is respectively connected to the first input end, the intermediate node, and the output end, and is used to control the level flip delay length of the signal of the intermediate node according to the second power supply signal, the first local oscillator signal, and the second local oscillator signal.

5. A local oscillator phase calibration device, characterized in that: include: The local oscillator phase adjustment circuit according to any one of claims 1 to 4; A local oscillator phase calibration circuit is connected to the local oscillator phase adjustment circuit, and is used to obtain an orthogonal baseband signal and an in-phase baseband signal, determine a current fine-tuning signal according to the orthogonal baseband signal and the in-phase baseband signal, and send the current fine-tuning signal to the local oscillator phase adjustment circuit.

6. A receiver, characterized in that: include: A local oscillator signal generating circuit, configured to generate a first local oscillator signal; The local oscillator phase calibration device according to claim 5, connected to the local oscillator signal generating circuit, and configured to calibrate the first local oscillator signal into a second local oscillator signal; a down-conversion mixer, connected to the local oscillator phase calibration device, configured to mix the second local oscillator signal with the radio frequency signal to generate an orthogonal demodulation signal and an in-phase demodulation signal; a baseband filter connected to the down-conversion mixer, configured to filter the quadrature demodulated signal to generate a quadrature baseband signal; And filtering is performed on the in-phase demodulated signal to generate an in-phase baseband signal.

7. A local oscillator phase calibration method, characterized in that: Applied to the local oscillator phase calibration device according to claim 5, the method comprises: Obtaining a quadrature baseband signal and an in-phase baseband signal; determining a current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal; According to the current fine-tuning signal, the delay duration between the first local oscillation signal and the second local oscillation signal is controlled; wherein the phase difference between the first local oscillation signal and the second local oscillation signal is related to the delay duration.

8. The method according to claim 7, characterized in that Determining a current fine-tuning signal according to the quadrature baseband signal and the in-phase baseband signal includes: Acquire a first orthogonal baseband signal and a first in-phase baseband signal corresponding to a first radio frequency signal; the first radio frequency signal has a different frequency from the first local oscillator signal; Acquire a link gain and a baseband amplitude mismatch value according to the first orthogonal baseband signal and the first in-phase baseband signal; Acquire a second orthogonal baseband signal and a second in-phase baseband signal corresponding to a second radio frequency signal, wherein the second radio frequency signal has the same frequency as the first local oscillator signal; Acquire a phase of the second radio frequency signal according to the second orthogonal baseband signal and the link gain; Obtaining a local oscillator phase mismatch value according to the phase of the second radio frequency signal, the link gain, the baseband amplitude mismatch value, and the second in-phase baseband signal; The current fine-tuning signal is generated according to the local oscillator phase mismatch value.

9. The method according to claim 8, characterized in that After controlling the delay between the first local oscillation signal and the second local oscillation signal according to the current fine-tuning signal, the method further includes: Repeating the steps of obtaining a third quadrature baseband signal and a third in-phase baseband signal corresponding to the third radio frequency signal, and obtaining a local oscillator phase mismatch value according to the third quadrature baseband signal, the third in-phase baseband signal, the link gain, and the baseband amplitude mismatch value until the local oscillator phase mismatch value has a different sign from the local oscillator phase mismatch value obtained previously; The third radio frequency signal has the same frequency as the first local oscillator signal.

Images