Device and method for detecting and calibrating amplitude difference and phase difference among multi-channel signals

Abstract

The invention relates to the technical field of signal calibration, and provides a device and a method for detecting and calibrating amplitude difference and phase difference among multichannel signals, and the device comprises a first power divider, a phase shift attenuation assembly in a multichannel assembly, a coupler, a second power divider, a multipath electronic switch, an amplitude and phase difference detection assembly and a control panel, the control panel obtains amplitude differences and phase differences of all the channels through switching the channels and sends the amplitude differences and the phase differences to the phase shift attenuation assembly, so that calibration of the amplitude differences and the phase differences between the channels is achieved. According to the invention, real-time detection of the amplitude difference and the phase difference among multichannel signals is realized, real-time calibration is carried out according to the detection result, and the problem that detection and monitoring of the amplitude difference and the phase difference among channels of multichannel transmitting power amplifier equipment and phased array equipment are relatively difficult can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of signal calibration, and in particular to a device and method for detecting and calibrating amplitude and phase differences between multi-channel signals. Background Art

[0002] In modern communications, radar, electronic countermeasures, and complex phased array systems, the amplitude and phase consistency of each channel signal plays a vital role in ensuring the efficient operation of the entire system. The system often relies on multiple channels to send and receive signals, and the amplitude and phase relationship between signals directly affects many key performance indicators of the system.

[0003] In the actual system operation process, many factors will cause deviations in amplitude and phase between channels. Differences in components used, changes in working environment temperature, humidity and air pressure and other environmental conditions will affect the amplitude and phase between channels. In addition, as the system is used for a long time, the aging of components will also aggravate the deviation of amplitude and phase. Failure to calibrate in time will seriously affect the accuracy and reliability of the system.

[0004] However, traditional calibration methods have many shortcomings. The calibration method based on manual adjustment is not only inefficient, but also requires extremely high professional skills of the operator, and it is difficult to ensure the accuracy and consistency of the calibration. At the same time, the system needs to be calibrated in time when amplitude and phase problems occur. The manual calibration method has a large workload and low calibration accuracy, and cannot effectively meet the requirements for system accuracy and reliability. As multi-channel systems continue to develop towards high precision and high stability, a new and more effective multi-channel amplitude and phase detection calibration method is needed. Summary of the invention

[0005] In view of the current industry situation that it is difficult to detect and monitor the amplitude and phase differences between channels of multi-channel transmitting power amplifier equipment and phased array equipment, the present invention provides a device and method for detecting and calibrating the amplitude and phase differences between multi-channel signals.

[0006] The present invention provides a multi-channel signal amplitude difference and phase difference detection and calibration device, comprising a first power divider, a phase shift attenuation component in a multi-channel component, a coupler, a second power divider, a multi-channel electronic switch, an amplitude and phase difference detection component and a control board;

[0007] The input end of the first power divider A is used to input a radio frequency input signal, the first output end is connected to the multi-channel component to be tested, and the second output end is connected to the amplitude phase difference detection component;

[0008] There are n directional couplers B, which are respectively connected to n channels of the multi-channel component to be tested. The through end of each directional coupler is connected to the subsequent stage, and the coupling end is connected to the second power divider C.

[0009] There are n second power dividers C, the input end of each second power divider C is connected to the corresponding directional coupler, the first output end is connected to the amplitude difference and phase difference detection component via the multi-way electronic switch D, and the second output end is connected to the amplitude difference and phase difference detection component;

[0010] The control board is connected to the amplitude difference phase difference detection component and the multi-channel component.

[0011] In some embodiments, the amplitude difference and phase difference detection component E implements amplitude difference and phase difference detection based on ADI's AD8302 chip.

[0012] In some embodiments, each path of the multi-path electronic switch is equipped with a load resistor.

[0013] The present invention also provides a method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals, which is implemented based on the above-mentioned device for detecting and calibrating the amplitude difference and phase difference between multi-channel signals; the method comprises:

[0014] The RF input signal is divided into two RF output signals of equal amplitude and phase by the first power divider A, one of which is input into the multi-channel component to be tested, and the other is input into the amplitude and phase difference detection component as the first reference signal;

[0015] The multi-channel component to be tested generates n channel signals which enter n directional couplers B respectively; the through signal of directional coupler B is output to the subsequent stage, and the forward coupling signal is output to the second power divider C;

[0016] The second power divider C divides the forward coupling signal into two coupling signals of equal amplitude and phase, one coupling signal is output from the first output end to the multi-way electronic switch D, and the other coupling signal is output from the second output end to the amplitude difference and phase difference detection component E as the second reference signal;

[0017] The amplitude difference and phase difference detection component E detects the amplitude difference and phase difference of the signal to be tested according to the first reference signal and the second reference signal and outputs them to the control board;

[0018] The control board obtains the amplitude difference and phase difference of all channels by switching channels and sends them to the phase shift attenuation component, so as to calibrate the amplitude difference and phase difference between channels.

[0019] In some embodiments, the control board stores the amplitude difference and phase difference of all channels, calculates the amplitude and phase correction compensation table of each channel based on the amplitude difference and phase difference between the channels, and then sends it to the phase shift attenuation components of each channel to achieve calibration of the amplitude difference and phase difference between the channels.

[0020] In some embodiments, in the amplitude and phase correction compensation table, the calibration values ​​of amplitude and phase are:

[0021] The calibration value X of the amplitude of channel n = ((X1+X2+…+Xn) / n)-Xn;

[0022] The calibration value of the n phase of the channel Y = ((Y1 + Y2 + ... + Yn) / n) - Yn;

[0023] Among them, the phase difference between test channel 1 and the input signal is X1, and the amplitude difference is Y1; the phase difference between test channel 2 and the input signal is X2, and the amplitude difference is Y2; the phase difference between test channel n and the input signal is Xn, and the amplitude difference is Yn.

[0024] In some embodiments, the calibration value needs to be optimized according to the accuracy of the phase shift and attenuation component.

[0025] In some embodiments, the optimized calibration value is:

[0026] The calibration value of the amplitude of the optimized channel n is X'=(X / a)*a;

[0027] The optimized calibration value of the n phases of the channel is Y'=(Y / b)*b;

[0028] Wherein, a is the minimum phase shift step of the phase shift attenuation component, and b is the minimum attenuation step of the phase shift attenuation component.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. In view of the current industry situation that it is difficult to detect and monitor the amplitude and phase differences between channels of multi-channel transmitting power amplifier equipment and phased array equipment, the present invention provides a device and method for detecting and calibrating the amplitude and phase differences between multi-channel signals, which can realize real-time detection of the amplitude difference and phase difference between multi-channel signals, and perform real-time calibration according to the detection results. It can solve the problem that it is difficult to detect and monitor the amplitude and phase differences between channels of multi-channel transmitting power amplifier equipment and phased array equipment, and is of great significance to promoting multi-channel amplitude and phase detection.

[0031] 2. The present invention uses a high-speed detection link and utilizes actual working signal testing and calibration, which can achieve rapid detection without the need for an additional calibration source, and can be calibrated at any time, greatly improving the convenience and speed of amplitude and phase difference detection and calibration between channels of multi-channel transmitting power amplifier equipment and phased array equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The present invention is a schematic diagram of a device for detecting and calibrating amplitude and phase differences between multi-channel signals provided in an embodiment of the present invention.

[0033] Figure 2 This is the internal schematic diagram of the AD8302 chip.

[0034] Figure 3 The present invention provides a flowchart of a method for detecting and calibrating amplitude and phase differences between multi-channel signals in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] like Figure 1 As shown, an embodiment of the present invention proposes an amplitude difference and phase difference detection and calibration device between multi-channel signals, including a first power divider, a phase shift attenuation component in a multi-channel component, a coupler, a second power divider, a multi-way electronic switch, an amplitude phase difference detection component and a control board.

[0038] The input end of the first power divider A is used to input the RF input signal, and the input RF input signal is divided into two RF output signals of equal amplitude and phase through the first power divider A. The first output end is connected to the multi-channel component to be tested, and is used to input one of the RF output signals into the multi-channel component to be tested. The second output end is connected to the amplitude phase difference detection component, and is used to input the other RF output signal as the first reference signal into the amplitude phase difference detection component.

[0039] There are n directional couplers B, which correspond to the n channels of the multi-channel component to be tested. After one RF output signal passes through the multi-channel component to be tested, n channel signals are generated and enter n directional couplers respectively. The through end of each directional coupler is connected to the subsequent stage, which is used to output the through signal to the subsequent stage through the through end of the directional coupler. The coupling end of the directional coupler is connected to the second power divider C, which is used to output the forward coupling signal to the second power divider C through the coupling end of the directional coupler.

[0040] There are n second power dividers C, and the input end of each second power divider C is connected to the corresponding directional coupler B for inputting a forward coupling signal. The forward coupling signal is divided into two coupling signals of equal amplitude and phase through the second power divider C. One coupling signal is output from the first output end to the multi-way electronic switch D, and the other coupling signal is output from the second output end to the amplitude difference and phase difference detection component E as a second reference signal.

[0041] The multi-way electronic switch D is used to select one of the n coupled signals output by the n second power dividers C and output it to the amplitude difference and phase difference detection component E. In order to reduce the reflected signal of the port, each of the multi-way electronic switches is equipped with a load resistor. The control board controls the multi-way electronic switch to select the channel to be calibrated in the multi-channel component to be tested, and the coupled signal corresponding to the selected channel enters the amplitude difference and phase difference detection component as the signal to be tested.

[0042] The amplitude difference and phase difference detection component E is used to detect the amplitude difference and phase difference of the signal to be tested according to the first reference signal and the second reference signal and output them to the control board.

[0043] In some embodiments, the amplitude difference and phase difference detection component E implements amplitude difference and phase difference detection based on the AD8302 chip of ADI. The internal schematic diagram of the AD8302 chip is shown in FIG. Figure 2 The AD8302 chip contains two precisely matched broadband logarithmic amplifiers, a broadband phase detector, and a 1.8V precision reference source, which can simultaneously measure the amplitude difference and phase difference between two input signals in the frequency range from low frequency to 2.7GHz.

[0044] When detecting the amplitude difference, the dynamic range between the two signals is ±30dB, the sensitivity of the output level is 30mV / dB, the measurement error is less than 0.5dB, the output voltage corresponding to -30dB is 30mV, and the output voltage corresponding to +30dB is 1.8V, and the output level conversion rate is 25V / us;

[0045] When detecting phase difference, the measurement range of phase difference is 0°~180°, the corresponding output voltage range is 0V~1.8V, the output voltage sensitivity is 10mV / °, and the measurement error is less than 0.5°. The conversion rate of phase output is 30MHz, and the response time is 40ns~500ns.

[0046] The second reference signal corresponding to the signal to be measured is compared with the first reference signal, and the comparison result is converted into an amplitude difference voltage analog quantity and a phase difference voltage analog quantity, and transmitted to the control board.

[0047] The control board can obtain the analog quantities of the amplitude difference voltage and the phase difference voltage of different channels relative to the reference signal by switching channels, so as to obtain the amplitude differences and phase differences of all channels, store the amplitude differences and phase differences of all channels, calculate the amplitude and phase correction compensation tables of each channel according to the amplitude differences and phase differences between channels, and then uniformly send them to the phase shift attenuation components of each channel to achieve the calibration of the amplitude differences and phase differences between channels. This avoids the detection errors caused by time when detecting and calibrating one channel at a time, and ensures that the same signal is detected within a period of time.

[0048] Therefore, based on the above-mentioned amplitude difference and phase difference detection and calibration device between multi-channel signals, as Figure 3 shown, a method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals includes the following steps:

[0049] S1, The radio frequency input signal is divided into two equal-amplitude and equal-phase radio frequency output signals by the first power divider A. One of the radio frequency output signals is input into the multi-channel component to be tested, and the other radio frequency output signal is input into the amplitude and phase difference detection component as the first reference signal;

[0050] S2, The multi-channel component to be tested generates n channel signals and enters n directional couplers B respectively; the through signals of the directional couplers B are output to the subsequent stage, and the forward coupled signals are output to the second power divider C;

[0051] S3, The second power divider C divides the forward coupled signal into two equal-amplitude and equal-phase coupled signals. One of the coupled signals is output from the first output end to the multi-channel electronic switch D, and the other coupled signal is output to the amplitude and phase difference detection component E as the second reference signal from the second output end;

[0052] S4, The amplitude and phase difference detection component E detects the amplitude difference and phase difference of the signal to be tested according to the first reference signal and the second reference signal and outputs them to the control board;

[0053] S5, The control board obtains the amplitude differences and phase differences of all channels by switching channels and sends them to the phase shift attenuation component, so as to achieve the calibration of the amplitude differences and phase differences between channels.

[0054] In step S5, when the phase difference between the test channel 1 and the input signal is X1 and the amplitude difference is Y1; the phase difference between the test channel 2 and the input signal is X2 and the amplitude difference is Y2; the phase difference between the test channel n and the input signal is Xn and the amplitude difference is Yn. In this embodiment, the unit of phase is ° and the unit of amplitude is dB.

[0055] Then the calibration value of channel n should be:

[0056] The calibration value X of the amplitude of channel n = ((X1+X2+…+Xn) / n)-Xn;

[0057] The calibration value of the n phase of the channel Y = ((Y1 + Y2 + ... + Yn) / n) - Yn;

[0058] In some embodiments, considering the accuracy of the phase shift attenuation component, the minimum phase shift step is a, and the minimum attenuation step is b. We need to optimize the calibration values ​​X and Y:

[0059] The calibration value of the amplitude of the optimized channel n is X'=(X / a)*a;

[0060] The optimized calibration value of the n phases of the channel is Y'=(Y / b)*b;

[0061] In this way, the calibration values ​​of all channels can be obtained, thereby obtaining the amplitude and phase correction compensation table of each channel. The control board stores this amplitude and phase correction compensation table, and performs automatic calibration compensation in the next standby state to assign values ​​to the phase shift attenuation components.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-channel signal amplitude difference and phase difference detection and calibration device, characterized in that: It includes a first power divider, a phase shift attenuation component in a multi-channel component, a coupler, a second power divider, a multi-channel electronic switch, an amplitude phase difference detection component and a control board; The input end of the first power divider A is used to input a radio frequency input signal, the first output end is connected to the multi-channel component to be tested, and the second output end is connected to the amplitude phase difference detection component; There are n directional couplers B, which are respectively connected to n channels of the multi-channel component to be tested. The through end of each directional coupler is connected to the subsequent stage, and the coupling end is connected to the second power divider C. There are n second power dividers C, the input end of each second power divider C is connected to the corresponding directional coupler, the first output end is connected to the amplitude difference and phase difference detection component via the multi-way electronic switch D, and the second output end is connected to the amplitude difference and phase difference detection component; The control board is connected to the amplitude difference phase difference detection component and the multi-channel component.

2. The multi-channel signal amplitude difference and phase difference detection and calibration device according to claim 1, characterized in that: The amplitude difference and phase difference detection component E realizes amplitude difference and phase difference detection based on the AD8302 chip of ADI.

3. The multi-channel signal amplitude difference and phase difference detection and calibration device according to claim 1, characterized in that: Each channel of the multi-channel electronic switch is equipped with a load resistor.

4. A method for detecting and calibrating amplitude and phase differences between multi-channel signals, characterized in that: It is implemented based on the multi-channel signal amplitude difference and phase difference detection and calibration device according to any one of claims 1 to 3; The method comprises: The RF input signal is divided into two RF output signals of equal amplitude and phase by the first power divider A, one of which is input into the multi-channel component to be tested, and the other is input into the amplitude and phase difference detection component as the first reference signal; The multi-channel component to be tested generates n channel signals which enter n directional couplers B respectively; the through signal of directional coupler B is output to the subsequent stage, and the forward coupling signal is output to the second power divider C; The second power divider C divides the forward coupling signal into two coupling signals of equal amplitude and phase, one coupling signal is output from the first output end to the multi-way electronic switch D, and the other coupling signal is output from the second output end to the amplitude difference and phase difference detection component E as the second reference signal; The amplitude difference and phase difference detection component E detects the amplitude difference and phase difference of the signal to be tested according to the first reference signal and the second reference signal and outputs them to the control board; The control board obtains the amplitude difference and phase difference of all channels by switching channels and sends them to the phase shift attenuation component, so as to calibrate the amplitude difference and phase difference between channels.

5. The method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals according to claim 4, characterized in that: The control board stores the amplitude difference and phase difference of all channels, calculates the amplitude and phase correction compensation table of each channel according to the amplitude difference and phase difference between the channels, and then sends it to the phase shift attenuation components of each channel to realize the calibration of the amplitude difference and phase difference between the channels.

6. The method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals according to claim 5, characterized in that: In the amplitude and phase correction compensation table, the calibration values ​​of amplitude and phase are: The calibration value X of the amplitude of channel n = ((X1+X2+…+Xn) / n)-Xn; The calibration value of the n phase of the channel Y = ((Y1 + Y2 + ... + Yn) / n) - Yn; Among them, the phase difference between test channel 1 and the input signal is X1, and the amplitude difference is Y1; the phase difference between test channel 2 and the input signal is X2, and the amplitude difference is Y2; the phase difference between test channel n and the input signal is Xn, and the amplitude difference is Yn.

7. The method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals according to claim 6, characterized in that: The calibration value needs to be optimized according to the accuracy of the phase shift and attenuation component.

8. The method for detecting and calibrating the amplitude difference and phase difference between multi-channel signals according to claim 7, characterized in that: The optimized calibration values ​​are: The calibration value of the amplitude of the optimized channel n is X'=(X / a)*a; The optimized calibration value of the n phases of the channel is Y'=(Y / b)*b; Wherein, a is the minimum phase shift step of the phase shift attenuation component, and b is the minimum attenuation step of the phase shift attenuation component.

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