CN-122026099-A - Electromagnetic characteristic optimization method for radio frequency signal transmission channel in tile type phased array system

Abstract

The invention discloses a method for optimizing electromagnetic characteristics of a radio frequency signal transmission channel in a tile type phased array system, and belongs to the field of radio frequency and microwaves. The method comprises the steps of establishing a three-dimensional electromagnetic field numerical calculation model of a radio frequency signal transmission channel, simulating and analyzing TDR parameters of the radio frequency signal transmission channel, calculating impedance mutation points of the signal transmission channel, and optimizing characteristic impedance of the impedance mutation points based on an anti-bonding pad, a trapezoid bonding pad and a reference plane slotting compensation mode to finish optimization of the radio frequency signal transmission channel. The invention adopts a mode of combining simulation analysis and experimental test, and can improve the signal integrity of electronic equipment and systems.

Inventors

• XU XIAOLONG
• CUI XIAODONG
• FAN JINGXU
• Ma Pingzhao
• HE PINXI
• GAO JINCHUN
• ZHANG TIANMENG
• ZHANG ZIYANG
• GUO CHAOZONG
• SONG QINGHUI
• ZHANG HAIFU
• WANG YATAO
• LI BIN
• Luo hanyang

Assignees

• 中国电子科技集团公司第五十四研究所
• 北京邮电大学

Dates

Publication Date

20260512

Application Date

20260130

Claims (7)

1. 1. The electromagnetic characteristic optimization method for the radio frequency signal transmission channel in the tile type phased array system is characterized by comprising the following steps of: step 1, establishing a three-dimensional electromagnetic field numerical calculation model of a radio frequency signal transmission channel; step 2, simulating and analyzing the TDR parameter of the radio frequency signal transmission channel, and calculating the impedance mutation point of the signal transmission channel; And 3, optimizing the characteristic impedance of the impedance mutation points based on the anti-bonding pad, the trapezoid bonding pad and the reference plane slotting compensation mode, and completing the optimization of the radio frequency signal transmission channel.
2. 2. The method for optimizing electromagnetic properties of a radio frequency signal transmission channel in a tile-type phased array system of claim 1, wherein the radio frequency signal transmission channel is a four-layer circuit board carrying a radio frequency connector, a peripheral radio frequency circuit, a packaging structure and a radio frequency chip, wherein the peripheral radio frequency circuit comprises a coplanar waveguide, a bonding pad, a via hole, a blind hole and a coaxial-coplanar waveguide switching structure, and the packaging structure is a ball grid array packaging structure.
3. 3. The method for optimizing electromagnetic properties of a radio frequency signal transmission channel in a tile-type phased array system according to claim 2, wherein the four-layer circuit board comprises a top layer, a first middle layer, a second middle layer and a bottom layer, and two adjacent layers are separated by a dielectric substrate; The coplanar waveguide comprises a signal conductor positioned at a first intermediate layer, a grounding conductor positioned at a top layer, the first intermediate layer, a second intermediate layer and a bottom layer, a dielectric substrate positioned among the top layer, the first intermediate layer, the second intermediate layer and the bottom layer, and a grounding via hole penetrating through all layers; The coaxial-coplanar waveguide switching structure comprises a coaxial connector, a signal pad and a blind hole for connecting the signal pad and a signal conductor; the ball grid array package structure is used for connecting a peripheral radio frequency circuit and a radio frequency chip.
4. 4. The method for optimizing electromagnetic characteristics of a radio frequency signal transmission channel in a tile type phased array system according to claim 2, wherein the three-dimensional electromagnetic field numerical calculation model is built through electromagnetic field simulation software, the electromagnetic field simulation software is built with a size and material parameter library of each structure in the radio frequency signal transmission channel in advance, and when the three-dimensional electromagnetic field numerical calculation model is built, similar structures in the three-dimensional electromagnetic field numerical calculation model are built in batches according to corresponding structure parameters.
5. 5. The method of optimizing electromagnetic properties of a radio frequency signal transmission channel in a tile phased array system of claim 2, wherein the impedance discontinuity is located at a solder ball of a co-axial-co-planar waveguide transfer structure, a via, a co-planar waveguide, and a ball grid array package structure.
6. 6. The method for optimizing electromagnetic characteristics of a radio frequency signal transmission channel in a tile phased array system according to claim 1, wherein the specific manner of step 3 is as follows: aiming at the coaxial-coplanar waveguide switching structure, a trapezoid gradient bonding pad is adopted to replace a rectangular bonding pad, the length-width ratio of the trapezoid gradient bonding pad is scanned, optimization is carried out with the interface impedance closest to 50 ohms as a target, and the optimal parameter combination is determined; On the basis of the model comprising the optimal trapezoid gradual change bonding pad, introducing anti-bonding pad structures with different shapes to the solder balls of the coaxial-coplanar waveguide switching structure, the blind holes and the ball grid array packaging structure, and cooperatively optimizing the lengths of the anti-bonding pads at different positions, the widths of the library and the sizes of the radius lamps to adjust the characteristic impedance of the coaxial-coplanar waveguide switching structure, the through holes and the solder balls to be within 50 omega +/-5%; In an electromagnetic field model of a complete signal channel containing the optimization results of the first two steps, a slot is etched on a reference ground plane below a coplanar waveguide, a ground via hole array around the channel is used as an electromagnetic interference isolation barrier, the shape and layout of the slot are consistent with those of the coplanar waveguide, the slot width is scanned, the voltage standing wave ratio of the system reaches standard in a full frequency band, the maximum of S21 parameters is a primary target in the full frequency band, the characteristic impedance of the channel is the flattest secondary target, and the optimal slot width is determined.
7. 7. The method for optimizing electromagnetic properties of a radio frequency signal transmission channel in a tile phased array system according to claim 6, wherein the voltage standing wave ratio is obtained by converting an S parameter obtained by a vector network test.

Description

Electromagnetic characteristic optimization method for radio frequency signal transmission channel in tile type phased array system Technical Field The invention relates to the field of radio frequency and microwaves, in particular to a method for optimizing electromagnetic characteristics of a radio frequency signal transmission channel in a tile type phased array system. Background Tile-type phased array antennas are one of the key technologies widely adopted in modern radar, communication systems. The tile structure integrates a large number of high-density transceiver components, high-speed digital control circuits, power management units, and multi-layer high-density interconnect substrates within a small-scale "tile" and is tightly packed. This high density integration results in a more complex electromagnetic environment within the system and a significant enhancement of electromagnetic coupling effects. In addition, the development of high density has led to a dramatic increase in impedance discontinuities within the system (e.g., such as e-microstrip transitions, inter-layer vertical interconnects, different material interfaces, vias, chip-package interfaces, inter-tile blind mate connectors, etc.). Furthermore, it is possible to provide a device for the treatment of a disease. In the radio frequency range, the dimensions of the interconnect structure can be compared to the wavelength of electromagnetic waves. The combined action of these factors makes the impedance mismatch problem of the whole signal transmission channel become prominent, and further causes problems such as increased signal reflection, reduced signal integrity, reduced channel isolation and the like. More seriously, in the high-power working state, the reflected power can be converted into heat energy, so that the local heat generation of the system is aggravated, the heat dissipation burden of the system is increased, and the reliability of the system is affected. The research on the electromagnetic characteristics of the tile type phased array system is one of key core technologies for solving the electromagnetic compatibility problem caused by the complex electromagnetic environment in the system and guaranteeing the reliable operation. At present, most researches on a tile type phased array system focus on the design of a phased array radar antenna structure and the design of a beam control circuit, and few researches on electromagnetic characteristics and optimal designs in the tile type phased array system. In addition, the impedance compensation of the channel routing focuses more on the aspects of optimizing design of line width and line spacing, and the method faces practical limitations such as layout space and processing tolerance. Disclosure of Invention In view of the above, the invention provides a method for optimizing electromagnetic characteristics of a radio frequency signal transmission channel in a tile-type phased array system. The invention effectively avoids the electromagnetic interference problem caused by the traditional optimal design under the limitation of layout space, and can also remarkably improve the signal integrity of the tile type phased array system. The invention adopts the technical scheme that: The electromagnetic characteristic optimization method of the radio frequency signal transmission channel in the tile type phased array system comprises the following steps: step 1, establishing a three-dimensional electromagnetic field numerical calculation model of a radio frequency signal transmission channel; step 2, simulating and analyzing the TDR parameter of the radio frequency signal transmission channel, and calculating the impedance mutation point of the signal transmission channel; And 3, optimizing the characteristic impedance of the impedance mutation points based on the anti-bonding pad, the trapezoid bonding pad and the reference plane slotting compensation mode, and completing the optimization of the radio frequency signal transmission channel. Further, the radio frequency signal transmission channel is a four-layer circuit board carrying a radio frequency connector, a peripheral radio frequency circuit, a packaging structure and a radio frequency chip, wherein the peripheral radio frequency circuit comprises a coplanar waveguide, a bonding pad, a via hole, a blind hole and a coaxial-coplanar waveguide switching structure, and the packaging structure is a ball grid array packaging structure. Further, the four-layer circuit board comprises a top layer, a first middle layer, a second middle layer and a bottom layer, and two adjacent layers are separated by a dielectric substrate; The coplanar waveguide comprises a signal conductor positioned at a first intermediate layer, a grounding conductor positioned at a top layer, the first intermediate layer, a second intermediate layer and a bottom layer, a dielectric substrate positioned among the top layer, the first intermediate layer, the