A calibration method for a power splitter board, a TR component, and a calibration method for a radio frequency front end

Abstract

The present invention relates to the field of electronic communication technology, and in particular to a calibration method for a power splitter board, a TR component, and a calibration method for a radio frequency front end. The power splitter board includes a top metal layer, a normal signal transmission layer, an isolation layer, a self-calibration function signal transmission layer, and a bottom metal layer from top to bottom; the normal signal transmission layer is provided with a first power splitter network and a main signal strip line connected, and the self-calibration function signal transmission layer is provided with a second power splitter network; the normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer; the normal signal transmission layer is provided with a coupler for coupling with a signal on the main signal strip line; the load end of the coupler is connected to a load, the input end of the coupler is connected to the calibration strip line, and the calibration strip line passes through the via hole and is connected to the second power splitter network. Through the calibration method for the power splitter board, the TR component, and the calibration method for the radio frequency front end, it is not necessary to build a darkroom far field, and a variety of self-calibration functions can be achieved using limited area and thickness.

Description

Technical Field

[0001] The present invention relates to the field of electronic communication technology, and in particular to a calibration method for a power splitter board, a TR component, and a calibration method for a radio frequency front end. Background Art

[0002] The RF front end is composed of integrated RF components, power splitter boards, TR components, wave control components, power supply components and antennas. The power splitter board is a passive circuit that connects the integrated RF components and TR components. The traditional RF front end power splitter board is composed of multiple power splitters and SMP RF connectors, and the power and frequency distribution and synthesis of fixed ports are achieved through the power splitter network, so as to achieve the purpose of signal transmission between the integrated RF components and the integrated TR components.

[0003] As the working environment such as temperature and humidity changes, the performance indicators of the RF front end such as power and phase may drift. At the same time, after the RF front end has been working for a long time or has been placed, the performance of the chip will also change, which will cause the front end to not work in the best state. In addition, after the RF front end is assembled, it is impossible to monitor and compensate for the modular and integrated indicators of the product in real time during the working process, and if a component is damaged, it may not be possible to locate the problem immediately. The RF front end needs to be disassembled and the single module needs to be checked one by one, which will cause problems such as status changes and increased workload.

[0004] Furthermore, in the prior art, calibration methods generally require the construction of a darkroom far field, which results in low verification efficiency. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a calibration method for a power splitter board, a TR component and a calibration method for a radio frequency front end, which does not require the construction of a darkroom far field and utilizes a limited area and thickness to achieve multiple self-calibration functions, thereby reducing the verification time and ensuring the stability of the performance indicators of the whole machine, and is not susceptible to external electromagnetic interference.

[0006] The present invention is achieved by adopting the following technical solutions: A power division board comprises, from top to bottom, a top metal layer, a normal signal transmission layer, an isolation layer, a self-calibration function signal transmission layer and a bottom metal layer; the normal signal transmission layer is provided with a first power division network and a main signal strip line connected to each other, and the self-calibration function signal transmission layer is provided with a second power division network; one end of the first power division network and the second power division network are respectively connected to a TR component through the same SMP connector, and the other end is also respectively connected to an integrated radio frequency component through the same SMP connector; the normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer; the normal signal transmission layer is provided with a coupler for coupling with a signal on the main signal strip line; the load end of the coupler is connected to a load, the input end of the coupler is connected to the calibration strip line, and the calibration strip line is connected to the second power division network through the via.

[0007] The load is disposed on the top metal layer.

[0008] The isolation layer includes a first isolation layer and a second isolation layer.

[0009] The load end of the coupler is arranged at a side away from the TR component.

[0010] The position of the coupled strip line of each combined circuit on the power splitter board is consistent with the number of corners of the strip line.

[0011] A third power division network is also provided on the normal signal transmission layer.

[0012] The lengths of the wirings in the third power division network are consistent.

[0013] A calibration method for a TR component based on the power splitter board, comprising transmitting calibration of the TR component and receiving calibration of the TR component; The transmission calibration of the TR component specifically refers to: inputting the excitation signal to the power splitter board, dividing the excitation signal into multiple paths through the second power splitter network on the self-calibration function signal transmission layer, reaching the normal signal transmission layer through the via, coupling the excitation signal to the main signal line through the coupler, and then distributing the signal to the TR component according to demand through the first power splitter network; after passing through the transmission channel of the TR component, it is transmitted from the antenna, and the signal is received by the antenna outside, thereby realizing data collection and calibration; The receiving calibration of the TR component specifically refers to: multiple signals are transmitted from the antenna, pass through the receiving channel of the TR component, enter the first power division network that reaches the normal signal transmission layer through the SMP connector, and are power synthesized to the main signal line. Each group of signals is coupled to the calibration line through a coupler, and then transmitted to the self-calibration function signal transmission layer through a via. After being synthesized into one path through the second power division network, they are divided into two paths, and then one of the ports is selected for output to achieve data collection and calibration.

[0014] A calibration method for a radio frequency front end based on the power splitter board, comprising performing a transmission calibration on the radio frequency front end and performing a reception calibration on the radio frequency front end; The transmission calibration of the RF front end specifically refers to: the excitation signal enters from the integrated RF component, passes through the transmission channel of the integrated RF component, the first power division network in the normal signal transmission layer of the power division board, and the transmission channel of the TR component to reach the antenna, and then couples the signal to the calibration link of the TR component through stripline coupling, and after power synthesis in the third power division network in the normal signal transmission layer of the power division board, it is output to the calibration channel of the integrated RF component, and data collection is realized through AD acquisition; The receiving calibration of the RF front end specifically refers to: the excitation signal enters from the integrated RF component, is coupled and output at the transmitting end of the integrated RF component to the third power division network in the normal signal transmission layer of the power division board, and its signal is power-distributed and output to the calibration channel of the TR component, and then coupled through the antenna port to reach the receiving channel of the TR component to reach the first power division network in the normal signal transmission layer of the power division board, and is output to the AD through the multi-channel reception of the integrated RF component to realize data collection.

[0015] When it is determined through the calibration method of the RF front end that there is a problem with the RF front end, the TR component is calibrated. If it is detected that there is no problem with the TR component, it is determined that there is a problem with the comprehensive RF component.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the present invention, by improving the structure of the power splitter board, while ensuring that the area of ​​the power splitter board remains unchanged, it is possible to utilize limited area and thickness to realize multiple self-calibration functions, and ensure the stability of the performance indicators of the whole machine, which is not easily affected by external electromagnetic interference.

[0017] Through the stacking design of the power splitter board, signal transmission is mainly carried out in the middle layer of the power splitter board and goes through different layers, saving area, ensuring the thickness of the power splitter board and the isolation of signals transmitted in different layers, and preventing mutual interference.

[0018] 2. In the present invention, the load is arranged on the top metal layer, which can reduce the cost.

[0019] 3. The isolation layer includes a first isolation layer and a second isolation layer, and has a good isolation effect.

[0020] 4. The load end of the coupler is set on the side away from the TR component. When the signal of the TR component reaches the power splitter board, more signals can be left because of the distance from the coupling. When the signal of the integrated RF component reaches the power splitter board, due to the reverse signal, the near end of the coupler becomes a load, and the signal will no longer go through the second power splitter network, but will be transmitted according to the original normal signal direction.

[0021] 5. The position of the coupled strip line of each combined circuit on the power splitter board and the number of corners of the strip line are kept consistent to ensure the consistency of phase and amplitude.

[0022] 6. The setting of the third power division network can better realize the calibration of the RF front end.

[0023] 7. The lengths of the various routing lines in the third power division network are consistent, which can ensure the consistency of phase and insertion loss.

[0024] 8. This method can be used to calibrate the TR components without disassembling the RF front end. In addition, there is no need to build a darkroom far field, and the limited area and thickness of the power splitter board can be used to achieve the calibration function, which can reduce the verification time.

[0025] 9. By combining the TR calibration method with the calibration method of the RF front end, and by routing different signal layers on the power splitter board, it is possible to quickly locate damaged components without disassembling the RF front end. It can also reduce the area, enhance signal isolation, and prevent mutual interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein: Figure 1 It is a schematic diagram of the structure of the power distribution board in the present invention; Figure 2 It is a schematic diagram of the stacking of the power splitter board in the present invention. DETAILED DESCRIPTION

[0027] Example 1 As a basic embodiment of the present invention, the present invention includes a power division board, which includes a top metal layer, a normal signal transmission layer, an isolation layer, a self-calibration function signal transmission layer and a bottom metal layer from top to bottom. The normal signal transmission layer is provided with a first power division network and a main signal strip line connected to each other, and the self-calibration function signal transmission layer is provided with a second power division network. One end of the first power division network and the second power division network are respectively connected to the TR component through the same SMP connector; the other ends of the first power division network and the second power division network are also respectively connected to the integrated RF component through another SMP connector. The normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer. The normal signal transmission layer is provided with a coupler for coupling with the signal on the main signal strip line. The load end of the coupler is connected to the load, the input end of the coupler is connected to the calibration strip line, and the calibration strip line is connected to the second power division network through the via.

[0028] Example 2 As a preferred embodiment of the present invention, the present invention includes a power division board, which includes a top metal layer, a normal signal transmission layer, an isolation layer, a self-calibration function signal transmission layer and a bottom metal layer from top to bottom. The normal signal transmission layer is provided with a first power division network and a main signal strip line connected to each other, and the self-calibration function signal transmission layer is provided with a second power division network. One end of the first power division network and the second power division network are respectively connected to the TR component through the same SMP connector. The other ends of the first power division network and the second power division network are respectively connected to the integrated radio frequency component through the same SMP connector. The normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer. The normal signal transmission layer is provided with a coupler for coupling with the signal on the main signal strip line. The load end of the coupler is connected to a load. Specifically, the load is arranged on the top metal layer. The input end of the coupler is connected to the calibration strip line, and the calibration strip line is connected to the second power division network through the via.

[0029] Based on the above power splitter board, the calibration of the TR component can be realized. The calibration method of the TR component can include transmitting calibration of the TR component and receiving calibration of the TR component.

[0030] The transmission calibration of the TR component specifically refers to: inputting the excitation signal to the power division board, dividing the excitation signal into multiple paths through the second power division network on the self-calibration function signal transmission layer, reaching the normal signal transmission layer through vias, coupling the excitation signal to the main signal line through the coupler, and then distributing the signal to the TR component as required through the first power division network; after passing through the transmission channel of the TR component, it is transmitted from the antenna, and the signal is received externally through the horn antenna, thereby realizing data collection and calibration.

[0031] The receiving calibration of the TR component specifically refers to: multiple signals are transmitted from the antenna, pass through the receiving channel of the TR component, enter the first power division network that reaches the normal signal transmission layer through the SMP connector, and are power synthesized to the main signal line. Each group of signals is coupled to the calibration line through a coupler, and then transmitted to the self-calibration function signal transmission layer through a via. After being synthesized into one path through the second power division network, they are divided into two paths, and then one of the ports is selected for output to achieve data collection and calibration.

[0032] Example 3 As another preferred embodiment of the present invention, refer to the attached Figure 2The present invention includes a power splitter board, which includes a top metal layer, a normal signal transmission layer, a first isolation layer, a second isolation layer, a self-calibration function signal transmission layer and a bottom metal layer from top to bottom. Since the three-proof treatment will cause the heat dissipation performance of the PCB surface to decrease, the signal line on the PCB surface is easily affected by the electromagnetic interference of the external environment. Therefore, the power splitter signal transmission of the present invention is mainly carried out in the middle layer, that is, in the normal signal transmission layer and the self-calibration function signal transmission layer. In order to ensure the thickness of the board and the isolation of the signals transmitted in different layers, the present invention adopts a 6-layer board structure, and the first isolation layer and the second isolation layer of the two middle layers serve as isolation.

[0033] The normal signal transmission layer is provided with a connected first power division network and a main signal strip line, and the self-calibration function signal transmission layer is provided with a second power division network. One end of the first power division network and the second power division network are respectively connected to the TR component through the same SMP connector, that is, they can be connected to the TR component through the first SMP connector. The other ends of the first power division network and the second power division network are also respectively connected to the integrated RF component through the same SMP connector, that is, they can be connected to the integrated RF component through the second SMP connector. The normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer. The normal signal transmission layer is provided with a coupler for coupling with the signal on the main signal strip line. The number of couplers corresponds to the number of channels of the integrated RF component.

[0034] Since the load end of the coupler does not need to output a signal, a load is connected, which can be set on the top metal layer and can be a 50Ohm resistor. The load end is far away from the TR component to control the transmission direction and power of the calibration signal. The input end of the coupler is connected to the calibration strip line, which passes through the via and is connected to the second power division network.

[0035] In order to achieve calibration of the RF front end, a third power division network is also provided on the normal signal transmission layer. The third power division network is composed of multiple power dividers, which synthesize the multi-channel output signals of the TR component into one channel and output it to the integrated RF component, or distribute the output signals of the integrated RF component into multiple channels and output them to the TR component. The routing length of each channel is kept consistent to ensure the consistency of phase and insertion loss.

[0036] The position of the coupled stripline and the number of corners of the stripline of each combined path on the power splitter board should be kept consistent as much as possible to ensure phase consistency. The trace length of the TR calibration should also be consistent from the design level to ensure phase and amplitude consistency. Among them, combining is the power divider combining multiple signals into one path, the coupled stripline of the combined path refers to the stripline of the normally transmitted signal, and the stripline refers to the signal line transmitted in the middle of the board.

[0037] Through the above power splitter board, a variety of self-calibration functions are realized by using limited area and thickness, and the stability of the performance indicators of the whole machine is guaranteed, and it is not easily affected by external electromagnetic interference. The specific design method of the above power splitter board may include: 1) Determine the input and output port locations, area, shape and thickness of the power splitter board; 2) Determine the model of the RF connector, paying special attention to the length of the pins; 3) Make a preliminary layout based on the area and shape of the power splitter board to determine the board stacking and thickness; 4) Determine the selection of PP and RF transmission media according to the process and material specifications and requirements provided by the plate maker, and set thresholds to ensure the processability of the design; 5) Simulate the power divider, SMP connector welding, transition between board layers and coupler to ensure that their return loss is less than -30dB within the operating frequency band; 6) Perform joint simulation on the above models to ensure that the return loss is less than -20dB within the operating frequency band; 7) Based on the simulation results, perform power distribution board layout on CAD software; 8) Import the CAD drawing results into the PCB board drawing software to draw the PCB board diagram of the power splitter.

[0038] Example 4 The basic principle of calibration is to adjust and correct the amplitude and phase changes in the antenna system due to aging and other factors by comparing the transmission and reception data stored internally before and after leaving the factory. In this regard, the present invention improves the structure of the power splitter board to achieve real-time monitoring and correction of performance indicators such as power and phase. The present invention completes the calibration of the TR component and the calibration of the RF front end on the basis of the power splitter board in Example 3.

[0039] Specifically, when the RF front end needs to perform transmit channel amplitude and phase calibration, the calibration method of the RF front end includes performing transmit calibration on the RF front end and performing receive calibration on the RF front end.

[0040] Transmit calibration of the RF front end specifically means: the excitation signal enters the integrated RF component, passes through the transmit channel of the integrated RF component, the first power division network in the normal signal transmission layer of the power division board, and the transmit channel of the TR component to reach the antenna, and then couples the signal to the calibration link of the TR component through stripline coupling, and after power synthesis in the third power division network in the normal signal transmission layer of the power division board, it is output to the calibration channel of the integrated RF component, and data collection is achieved through AD acquisition.

[0041] The receiving calibration of the RF front end specifically refers to: the excitation signal enters from the integrated RF component, is coupled and output at the transmitting end of the integrated RF component to the third power division network in the normal signal transmission layer of the power division board, and its signal is power-distributed and output to the calibration channel of the TR component, and then coupled through the antenna port to reach the receiving channel of the TR component to reach the first power division network in the normal signal transmission layer of the power division board, and is output to the AD through the multi-channel reception of the integrated RF component to realize data collection.

[0042] When the RF front end is judged to have a problem through the RF front end calibration method, the TR component is calibrated, and if it is detected that there is no problem with the TR component, it is judged that there is a problem with the integrated RF component. Among them, when the TR component is calibrated, that is, the amplitude and phase of the transmission channel of the TR component are calibrated, the calibration method of the TR component can include transmitting calibration of the TR component and receiving calibration of the TR component.

[0043] To calibrate the TR module, the following steps are performed: Input the excitation signal to the power splitter board (see the attached manual). Figure 1 The GF-J49 port in the self-calibration function signal transmission layer is divided into multiple paths by the power divider in the second power division network, and reaches the normal signal transmission layer, that is, the board layer where the coupler is located, through the via hole, and couples the excitation signal to the main signal line through the coupler, and then distributes the signal to the TR component according to the demand through the first power division network. After passing through the transmission channel of the TR component, it is transmitted from the antenna and received by the horn antenna outside, thereby realizing data collection and calibration.

[0044] The receiving calibration of the TR component specifically refers to: transmitting multiple signals from the antenna, passing through the receiving channel of the TR component, entering the first power division network that reaches the normal signal transmission layer through the SMP connector, and then being synthesized to the main signal line. Each group of signals is coupled to the calibration line through a coupler, and then transmitted to the self-calibration function signal transmission layer through a via, synthesized into one path through the second power division network, and then divided into two paths, and then one of the ports is selected for output (see the manual). Figure 1 GF-J50 port in the PCB) to realize data collection and calibration.

[0045] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the present invention without creative mental labor, which all fall within the scope of protection of the present invention.

Claims

1. A power splitter board, characterized in that: From top to bottom, it includes a top metal layer, a normal signal transmission layer, an isolation layer, a self-calibration function signal transmission layer and a bottom metal layer; the normal signal transmission layer is provided with a connected first power division network and a main signal strip line, and the self-calibration function signal transmission layer is provided with a second power division network; one end of the first power division network and the second power division network are respectively connected to the TR component through the same SMP connector, and the other end is also respectively connected to the integrated RF component through the same SMP connector; the normal signal transmission layer and the isolation layer are provided with vias connected to the self-calibration function signal transmission layer; the normal signal transmission layer is provided with a coupler for coupling with the signal on the main signal strip line; the load end of the coupler is connected to the load, the input end of the coupler is connected to the calibration strip line, and the calibration strip line is connected to the second power division network through the via.

2. A power splitter board according to claim 1, characterized in that: The load is disposed on the top metal layer.

3. A power splitter board according to claim 1, characterized in that: The isolation layer includes a first isolation layer and a second isolation layer.

4. A power splitter board according to claim 1, characterized in that: The load end of the coupler is arranged at a side away from the TR component.

5. A power splitter board according to claim 1, characterized in that: The position of the coupled strip line of each combined circuit on the power splitter board is consistent with the number of corners of the strip line.

6. A power splitter board according to any one of claims 1 to 5, characterized in that: A third power division network is also provided on the normal signal transmission layer.

7. A power splitter board according to claim 6, characterized in that: The lengths of the wirings in the third power division network are consistent.

8. A calibration method for a TR assembly based on the power splitter board according to claim 1, characterized in that: Including transmitting calibration of TR components and receiving calibration of TR components; The transmission calibration of the TR component specifically refers to: inputting the excitation signal to the power splitter board, dividing the excitation signal into multiple paths through the second power splitter network on the self-calibration function signal transmission layer, reaching the normal signal transmission layer through the via, coupling the excitation signal to the main signal line through the coupler, and then distributing the signal to the TR component according to demand through the first power splitter network; after passing through the transmission channel of the TR component, it is transmitted from the antenna, and the signal is received by the antenna outside, thereby realizing data collection and calibration; The receiving calibration of the TR component specifically refers to: multiple signals are transmitted from the antenna, pass through the receiving channel of the TR component, enter the first power division network that reaches the normal signal transmission layer through the SMP connector, and are power synthesized to the main signal line. Each group of signals is coupled to the calibration line through a coupler, and then transmitted to the self-calibration function signal transmission layer through a via. After being synthesized into one path through the second power division network, they are divided into two paths, and then one of the ports is selected for output to achieve data collection and calibration.

9. A calibration method for a radio frequency front end of a power splitter board according to claim 6, characterized in that: Including transmitting calibration of the RF front end and receiving calibration of the RF front end; The transmission calibration of the RF front end specifically refers to: the excitation signal enters from the integrated RF component, passes through the transmission channel of the integrated RF component, the first power division network in the normal signal transmission layer of the power division board, and the transmission channel of the TR component to reach the antenna, and then couples the signal to the calibration link of the TR component through stripline coupling, and after power synthesis in the third power division network in the normal signal transmission layer of the power division board, it is output to the calibration channel of the integrated RF component, and data collection is realized through AD acquisition; The receiving calibration of the RF front end specifically refers to: the excitation signal enters from the integrated RF component, is coupled and output at the transmitting end of the integrated RF component to the third power division network in the normal signal transmission layer of the power division board, and its signal is power-distributed and output to the calibration channel of the TR component, and then coupled through the antenna port to reach the receiving channel of the TR component to reach the first power division network in the normal signal transmission layer of the power division board, and is output to the AD through the multi-channel reception of the integrated RF component to realize data collection.

10. The calibration method of a radio frequency front end based on a power splitter board according to claim 9, characterized in that: When it is determined through the calibration method of the RF front end that there is a problem with the RF front end, the TR component is calibrated. If it is detected that there is no problem with the TR component, it is determined that there is a problem with the comprehensive RF component.

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