Amplitude-phase control circuit with calibration module

Abstract

The invention provides an amplitude-phase control circuit with a calibration module, and relates to the technical field of amplitude-phase control circuits. A first variable gain amplifier of the circuit can input a differential signal, and a feedback signal of an amplitude calibration circuit can perform amplitude calibration on an output signal of the first variable gain amplifier; the output end of the phase calibration circuit is connected with the feedback input end of the orthogonal generator, and a feedback signal generated by the phase calibration circuit can control the phase of an output signal of the orthogonal generator. The amplitude of an input signal of the first variable gain amplifier is controlled through a feedback signal generated by the amplitude calibration circuit, the effects of high-precision gain adjustment and phase stabilization in the gain adjustment process are achieved, and the phase of an input signal of the orthogonal generator is controlled through a feedback signal generated by the phase calibration circuit. Therefore, the output signal of the amplitude-phase control circuit has the advantage of small phase error, so that the amplitude-phase control circuit has the advantages of high gain adjustment precision, high phase adjustment precision and stable phase.

Description

Technical Field

[0001] The present specification relates to the technical field of amplitude and phase control circuits, and in particular, to an amplitude and phase control circuit with a calibration module. Background Art

[0002] With the rapid development of wireless communications and radar, phased array transceivers have been widely studied in recent years. As the core unit in the phased array system, the amplitude and phase control circuit needs to have excellent performance such as high gain adjustment accuracy and low phase error to ensure the signal quality in the phased array system, and plays a vital role in the phased array system. Among them, the amplitude control module can be implemented by attenuators and variable gain amplifiers (VGAs). VGAs can be divided into digital control VGAs and analog control VGAs according to the control signals. Compared with digital control VGAs, analog control VGAs require digital-to-analog converters (DACs) to achieve gain control, but it increases the complexity of the circuit. Low phase change with gain change is one of the key characteristics of VGAs. Adding a control circuit is a common method to achieve constant phase change during gain control, but this method increases the complexity of the circuit. Another way to compensate for phase is to set a PMOS tube and resistor at the output, which also requires additional control bits and makes the circuit more complicated. Summary of the invention

[0003] The purpose of this specification is to provide an amplitude-phase control circuit with a calibration module, which can overcome the above-mentioned defects of the existing amplitude-phase control circuit.

[0004] The embodiments of this specification are implemented as follows:

[0005] An amplitude and phase control circuit with a calibration module comprises an amplitude control module and a phase shift control module;

[0006] The amplitude control module includes a first variable gain amplifier and an amplitude calibration circuit, the output end of the first variable gain amplifier is connected to the input end of the amplitude calibration circuit, the output end of the amplitude calibration circuit is connected to the feedback input end of the first variable gain amplifier, the first variable gain amplifier can input a differential signal, and the feedback signal of the amplitude calibration circuit can perform amplitude calibration on the output signal of the first variable gain amplifier;

[0007] The phase shift control module includes an orthogonal generator, a second variable gain amplifier, a third variable gain amplifier and a phase calibration circuit. The input end of the orthogonal generator is connected to the output end of the first variable gain amplifier, the output end of the orthogonal generator is respectively connected to the input ends of the second variable gain amplifier and the third variable gain amplifier, the output end of the second variable gain amplifier and the output end of the third variable gain amplifier are respectively connected to the input end of the phase calibration circuit, the output end of the phase calibration circuit is connected to the feedback input end of the orthogonal generator, and the feedback signal generated by the phase calibration circuit can control the phase of the output signal of the orthogonal generator.

[0008] The embodiments of this specification have at least the following advantages or beneficial effects:

[0009] Compared with the prior art, the amplitude-phase control circuit with a calibration module can generate a feedback signal to control the amplitude of the input signal of the first variable gain amplifier by setting the amplitude calibration circuit, so as to achieve high-precision gain adjustment and phase stability during the gain adjustment process. Moreover, by setting the phase calibration circuit, a feedback signal can be generated to control the phase of the input signal of the orthogonal generator, so that the output signal of the amplitude-phase control circuit has the advantage of small phase error. It can be seen that the amplitude-phase control circuit has the advantages of high gain adjustment accuracy, high phase adjustment accuracy and phase stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of this specification, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present specification and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0011] Figure 1 A schematic diagram of the structure of an amplitude and phase control circuit with a calibration module provided in this specification;

[0012] Figure 2 Another structural schematic diagram of an amplitude and phase control circuit with a calibration module provided in this specification;

[0013] Figure 3 This is a schematic diagram of the structure of the orthogonal generator provided in this specification.

[0014] Icons: 1. First variable gain amplifier; 2. First analog-to-digital converter; 3. Amplitude calibration circuit; 31. First capacitor; 32. Second capacitor; 33. Multiplier; 34. First amplifier; 35. Bias circuit module; 4. Orthogonal generator; 5. Second variable gain amplifier; 6. Third variable gain amplifier; 7. Phase calibration circuit; 71. Coupler; 72. Second amplifier; 73. Low-pass filter; 74. Second analog-to-digital converter. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of this specification more clear, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are part of the embodiments of this specification, not all of the embodiments. Generally, the components of the embodiments of this specification described and shown in the drawings here can be arranged and designed in various different configurations.

[0016] Therefore, the following detailed description of the embodiments of the present specification provided in the accompanying drawings is not intended to limit the scope of the present specification claimed for protection, but merely represents selected embodiments of the present specification. Based on the embodiments in the present specification, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present specification.

[0017] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0018] In the description of the embodiments of this specification, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of this specification is usually placed when used. It is only for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on this specification. In addition, if the terms "first", "second", "third", etc. appear, they are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0019] In addition, the use of terms such as "horizontal", "vertical", and "overhanging" does not mean that the components must be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0020] In the description of the embodiments of this specification, it is also necessary to explain that, unless otherwise clearly specified and limited, the words "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be fixedly connected, detachably connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be internal communication between two components. For ordinary technicians in this field, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0021] Please refer to Figures 1 to 3 , an amplitude and phase control circuit with a calibration module provided in an embodiment of the present specification mainly includes an amplitude control module and a phase shift control module;

[0022] The amplitude control module includes a first variable gain amplifier 1 and an amplitude calibration circuit 3, the output end of the first variable gain amplifier 1 is connected to the input end of the amplitude calibration circuit 3, the output end of the amplitude calibration circuit 3 is connected to the feedback input end of the first variable gain amplifier 1, the first variable gain amplifier 1 can input a differential signal, and the feedback signal of the amplitude calibration circuit 3 can perform amplitude calibration on the output signal of the first variable gain amplifier 1;

[0023] The phase shift control module includes an orthogonal generator 4, a second variable gain amplifier 5, a third variable gain amplifier 6 and a phase calibration circuit 7. The input end of the orthogonal generator 4 is connected to the output end of the first variable gain amplifier 1, the output end of the orthogonal generator 4 is respectively connected to the input ends of the second variable gain amplifier 5 and the third variable gain amplifier 6, the output end of the second variable gain amplifier 5 and the output end of the third variable gain amplifier 6 are respectively connected to the input end of the phase calibration circuit 7, the output end of the phase calibration circuit 7 is connected to the feedback input end of the orthogonal generator 4, and the feedback signal generated by the phase calibration circuit 7 can control the phase of the output signal of the orthogonal generator 4.

[0024] Specifically, the amplitude-phase control circuit with a calibration module can generate a feedback signal to control the amplitude of the input signal of the first variable gain amplifier 1 by setting the above-mentioned amplitude calibration circuit 3, so as to achieve the effect of high-precision gain adjustment and phase stability during the gain adjustment process. Moreover, by setting the above-mentioned phase calibration circuit 7, it can generate a feedback signal to control the phase of the input signal of the orthogonal generator 4, so that the output signal of the above-mentioned amplitude-phase control circuit has the advantage of small phase error. It can be seen that the above-mentioned amplitude-phase control circuit has the advantages of high gain adjustment accuracy, high phase adjustment accuracy and phase stability.

[0025] In this embodiment, the quadrature generator 4 , the second variable gain amplifier 5 , and the third variable gain amplifier 6 cooperate to form a phase shift control circuit.

[0026] In this embodiment, the first variable gain amplifier 1 is connected to the first analog-to-digital converter 2, and the first analog-to-digital converter 2 can convert an analog control signal into a digital control signal to control the first variable gain amplifier 1 in a digital control manner.

[0027] In this embodiment, the first variable gain amplifier 1 adopts a digital control structure based on the Gilbert structure to amplify the first input signal and the second input signal. It can be seen that the amplitude control module can adjust the gain of the input signal of the first variable gain amplifier 1 in a digital control manner, while achieving the effect of constant input and output impedance, and can ensure the phase stability of the input signal.

[0028] In this embodiment, the amplitude calibration circuit 3 includes a self-mixer, a first amplifier 34 and a bias circuit module 35 connected in sequence, the input end of the self-mixer is connected to the output end of the first variable gain amplifier 1, and the output end of the bias circuit module 35 is connected to the feedback input end of the first variable gain amplifier 1.

[0029] In this embodiment, part of the output signal of the first variable gain amplifier 1 can be input to the self-mixer, and the self-mixer can convert the AC voltage of the part of the output signal into a DC voltage. The first amplifier 34 can perform voltage division comparison on the part of the output signal, and feed back part of the output signal of the first amplifier 34 to the bias circuit module 35. The gain of the first variable gain amplifier 1 is adjusted by the bias circuit module 35, thereby adjusting the response of the first variable gain amplifier 1, and then achieving the effect of calibrating the amplitude of the input signal of the first variable gain amplifier 1. It can be seen that the setting of the amplitude calibration circuit 3 can effectively reduce the amplitude error of the output signal.

[0030] In this embodiment, the input signal is taken as a plurality of signal data collected during a certain period of time as an example for explanation: the amplitude control module can generate a feedback signal according to the signal data at the current moment, and use the feedback signal to adjust the response parameters of the first variable gain amplifier 1, thereby adjusting the gain of the signal data input at the next moment, until the output reaches the expected output signal, thereby achieving the effect of calibrating the signal amplitude and reducing the signal amplitude error.

[0031] In this embodiment, the output signal of the first variable gain amplifier 1 is a first output signal and a second output signal which are differential signals of each other. The self-mixer includes a first capacitor 31, a second capacitor 32 and a multiplier 33. One end of the first capacitor 31 can input the first output signal, and the other end of the first capacitor 31 is connected to the input end of the multiplier 33. One end of the second capacitor 32 can input the second output signal, and the other end of the second capacitor 32 is connected to the input end of the multiplier 33. The output end of the multiplier 33 is connected to the first amplifier 34.

[0032] In this embodiment, the above configuration can output one feedback signal from two output signals through the amplitude calibration circuit 3, which can further reduce the complexity of the above circuit.

[0033] In this embodiment, the phase calibration circuit 7 includes a coupler 71, a second amplifier 72 and a second analog-to-digital converter 74 connected in sequence, the input end of the coupler 71 is connected to the output end of the second variable gain amplifier 5 and the output end of the third variable gain amplifier 6, and the output end of the second analog-to-digital converter 74 is connected to the feedback input end of the orthogonal generator 4.

[0034] In this embodiment, the signal output from the amplitude and phase control module after gain adjustment enters the phase shift control module for phase adjustment, and the input signal of the orthogonal generator 4 is phase adjusted by the setting of the phase calibration circuit 7 to reduce the phase error of the output signal of the above-mentioned amplitude and phase control circuit.

[0035] In this embodiment, a low-pass filter 73 is further provided between the second amplifier 72 and the second analog-to-digital converter 74 .

[0036] In this embodiment, the phase shift control module further includes an adder, the output end of the second variable gain amplifier 5 and the output end of the third variable gain amplifier 6 are respectively connected to the input end of the adder, and the output end of the adder is connected to the input end of the coupler 71. Through the above configuration, the I / Q signals output by the second variable gain amplifier 5 and the third variable gain amplifier 6 can be vector synthesized to obtain a signal with a specific phase.

[0037] In this embodiment, the second variable gain amplifier 5 and the third variable gain amplifier 6 are capable of performing amplitude control on the quadrature signal (I / Q signal) output by the quadrature generator 4 .

[0038] In this embodiment, the coupler 71 includes a first inductor and a second inductor, the input end of the first inductor is connected to the output end of the adder, the output end of the first inductor is a signal output end, the second inductor is coupled to the first inductor, and the output end of the second inductor is connected to the input end of the second amplifier 72.

[0039] In this embodiment, the output signal of the first variable gain amplifier 1 is a first output signal and a second output signal which are differential signals of each other. The orthogonal generator 4 includes four adjustable units, and the adjustable units are composed of adjustable resistors and adjustable capacitors arranged in parallel. Two adjacent adjustable units can input the first output signal to output two orthogonal signals, and the other two adjacent adjustable units can input the second output signal to output two orthogonal signals.

[0040] In this embodiment, the feedback signal generated by the phase calibration circuit 7 is used to control the adjustable resistor and the adjustable capacitor in the orthogonal generator 4 to reduce the phase error under different conditions. It can be seen that the above setting method can effectively improve the accuracy of the output signal of the amplitude and phase control module and reduce the phase error of the output signal of the amplitude and phase control module.

[0041] In this embodiment, the adjustable resistor is composed of a switch MOS tube and a resistor.

[0042] In this embodiment, the on and off states of the switch MOS tube are adjusted to control the size of the access resistor, thereby achieving the function of adjusting the resistor.

[0043] In this embodiment, the above-mentioned adjustable capacitor is a MOS tube. Since the parasitic capacitance of the MOS tube is different under different bias voltages, the magnitude of the parasitic capacitance is changed by adjusting the magnitude of the bias voltage.

[0044] In this embodiment, the signal after phase adjustment by the orthogonal generator 4 and the second variable gain amplifier 5 and the third variable gain amplifier 6 is input to the above-mentioned phase calibration circuit 7, and the feedback signal is fed back to the orthogonal generator 4 through the above-mentioned phase calibration circuit 7 to perform phase calibration, thereby achieving the effect of phase compensation.

[0045] In this embodiment, the phase calibration circuit 7 can perform phase compensation on the input signal by means of a feedback signal, that is, forming a phase compensation structure.

[0046] In this embodiment, the gain range of the amplitude-phase control circuit is -5dB to 10dB, and the gain step is 1dB. When the gain adjustment range is -5dB to 10dB, the phase change is only less than 1 degree. It can be seen that the amplitude-phase control circuit has the characteristics of high gain adjustment accuracy and stable phase.

[0047] The above are only preferred embodiments of this specification and are not intended to limit this specification. For those skilled in the art, this specification may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification shall be included in the protection scope of this specification.

Claims

1. An amplitude and phase control circuit with a calibration module, characterized in that: It includes an amplitude control module and a phase shift control module; The amplitude control module includes a first variable gain amplifier and an amplitude calibration circuit, the output end of the first variable gain amplifier is connected to the input end of the amplitude calibration circuit, the output end of the amplitude calibration circuit is connected to the feedback input end of the first variable gain amplifier, the first variable gain amplifier can input a differential signal, and the feedback signal of the amplitude calibration circuit can perform amplitude calibration on the output signal of the first variable gain amplifier; The phase shift control module includes an orthogonal generator, a second variable gain amplifier, a third variable gain amplifier and a phase calibration circuit. The input end of the orthogonal generator is connected to the output end of the first variable gain amplifier, the output end of the orthogonal generator is respectively connected to the input ends of the second variable gain amplifier and the third variable gain amplifier, the output end of the second variable gain amplifier and the output end of the third variable gain amplifier are respectively connected to the input end of the phase calibration circuit, the output end of the phase calibration circuit is connected to the feedback input end of the orthogonal generator, and the feedback signal generated by the phase calibration circuit can control the phase of the output signal of the orthogonal generator.

2. The amplitude and phase control circuit with a calibration module according to claim 1, characterized in that: The first variable gain amplifier is connected to a first analog-to-digital converter, and the first analog-to-digital converter can convert an analog control signal into a digital control signal to control the first variable gain amplifier in a digital control manner.

3. The amplitude and phase control circuit with a calibration module according to claim 1, characterized in that: The amplitude calibration circuit includes a self-mixer, a first amplifier and a bias circuit module connected in sequence, the input end of the self-mixer is connected to the output end of the first variable gain amplifier, and the output end of the bias circuit module is connected to the feedback input end of the first variable gain amplifier.

4. The amplitude and phase control circuit with a calibration module according to claim 3, characterized in that: The output signal of the first variable gain amplifier is a first output signal and a second output signal which are differential signals of each other. The self-mixer includes a first capacitor, a second capacitor and a multiplier. One end of the first capacitor can input the first output signal, and the other end of the first capacitor is connected to the input end of the multiplier. One end of the second capacitor can input the second output signal, and the other end of the second capacitor is connected to the input end of the multiplier. The output end of the multiplier is connected to the first amplifier.

5. The amplitude and phase control circuit with a calibration module according to claim 1, characterized in that: The phase calibration circuit includes a coupler, a second amplifier and a second analog-to-digital converter connected in sequence, the input end of the coupler is connected to the output end of the second variable gain amplifier and the output end of the third variable gain amplifier, and the output end of the second analog-to-digital converter is connected to the feedback input end of the orthogonal generator.

6. The amplitude and phase control circuit with a calibration module according to claim 5, characterized in that: A low-pass filter is further arranged between the second amplifier and the second analog-to-digital converter.

7. The amplitude and phase control circuit with a calibration module according to claim 5, characterized in that: The phase shift control module further includes an adder, the output end of the second variable gain amplifier and the output end of the third variable gain amplifier are respectively connected to the input end of the adder, and the output end of the adder is connected to the input end of the coupler.

8. The amplitude and phase control circuit with a calibration module according to claim 7, characterized in that: The coupler includes a first inductor and a second inductor, the input end of the first inductor is connected to the output end of the adder, the output end of the first inductor is a signal output end, the second inductor is coupled to the first inductor, and the output end of the second inductor is connected to the input end of the second amplifier.

9. The amplitude and phase control circuit with a calibration module according to claim 1, characterized in that: The output signal of the first variable gain amplifier is a first output signal and a second output signal which are differential signals of each other. The orthogonal generator includes four adjustable units, and the adjustable units are composed of adjustable resistors and adjustable capacitors arranged in parallel. Two adjacent adjustable units can input the first output signal to output two orthogonal signals, and the other two adjacent adjustable units can input the second output signal to output two orthogonal signals.

10. The amplitude and phase control circuit with a calibration module according to claim 9, characterized in that: The adjustable resistor is composed of a switch M0s tube and a resistor.

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