Mobile phone direct connection S-band phased array radio frequency system based on multi-layer mixed pressing plate technology

Abstract

The application relates to a mobile phone direct connection S-band phased array radio frequency system based on a multi-layer mixed pressing plate technology, and belongs to the technical field of low-orbit satellite wireless communication, and specifically relates to a mobile phone direct connection S-band phased array radio frequency system based on a multi-layer mixed pressing plate technology. The phased array radio frequency system contains a plurality of single-channel radio frequency components, each single-channel radio frequency component is internally integrated with a radio frequency SIP module, a power supply SIP module, a radio frequency PA and a transceiving filter; the complete radio frequency transceiving link and the calibration branch are highly integrated in the single-channel TR component with the size of 60*50*8mm, the overall structure and the peripheral interconnection design of the component are greatly simplified, the single-channel radio frequency component multiplexing and the small-size and light-weight design of the component are realized, and the S-band low-orbit satellite engineering application is adapted.

Description

Technical Field

[0001] This invention relates to the field of low-Earth orbit satellite wireless communication technology, specifically to a mobile phone direct-connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology. Background Technology

[0002] Against the backdrop of deepening 5G commercialization and forward-looking 6G technology deployment, S-band spaceborne antenna RF systems, due to their strong signal penetration and coverage advantages, have become a core element of mobile phone direct-to-satellite communication systems. Their basic principle involves using an array of multiple antenna elements and a beamforming network to control the amplitude and phase of each channel, achieving rapid electrical scanning and shaping of the beam, thereby ensuring a stable communication link between low-Earth orbit satellites and ordinary mobile terminals on the ground. Therefore, the miniaturization and integration, calibration accuracy, and mixed-signal design of the RF system are key factors determining antenna performance and engineering practicality. However, currently, S-band spaceborne antenna RF systems still face the following three technical challenges in engineering applications:

[0003] (1) Insufficient miniaturization and integration: Traditional design schemes use discrete components or modular assembly integration methods, resulting in bulky and heavy components, which are difficult to meet the lightweight and flat payload requirements of low-orbit satellites. In addition, the interconnection paths between components are long, which can easily cause serious signal attenuation and electromagnetic crosstalk, resulting in low power utilization and limiting the system's operating bandwidth and power efficiency.

[0004] (2) Low calibration accuracy and poor consistency: Existing calibration links mostly use external switching switches and independent calibration power dividers. The switching switches are deployed outside the TR module, which introduces additional insertion loss and path length differences, making it difficult to guarantee the phase and amplitude consistency between the transmit and receive links and the calibration links. At the same time, the external power divider network and the main RF feed network are independent of each other, and it is difficult to optimize the impedance matching and distribution uniformity of the two in a coordinated manner. Therefore, the calibration accuracy is limited and cannot meet the requirements of high-precision beamforming in the S-band.

[0005] (3) Lack of reasonable mixed-signal design: The RF component and the digital baseband component are mostly designed separately and deployed on multiple PCBs. The boards are interconnected by connectors, which introduces signal delay and impedance mismatch problems. Even if a layered PCB layout is used, it only relies on the isolation ground layer and does not have a systematic design of a dedicated high- and low-frequency mixed voltage board architecture and targeted shielding design. The isolation effect between the RF and digital areas is poor, which easily generates electromagnetic interference and makes it difficult to meet the dual requirements of low insertion loss transmission of S-band RF signals and high stability of digital signals at the same time.

[0006] In summary, S-band spaceborne phased array radio frequency systems have significant technical challenges in terms of miniaturization integration, calibration accuracy, and mixed-signal design, which urgently require new technical solutions to overcome. Summary of the Invention

[0007] To address the aforementioned problems, the purpose of this invention is to propose a direct-connect S-band phased array RF system for mobile phones based on multi-layer hybrid pressure board technology. With the envelope size of a single-channel RF component limited to 60×50×8mm, the microwave transceiver link, high-precision calibration branch, and digital control circuit are integrated into a single unit, achieving multi-channel multiplexing and miniaturized, lightweight component design, making it suitable for engineering applications of S-band low-Earth orbit satellites.

[0008] The phased array radio frequency system adopts a vertically layered assembly structure, which is arranged from bottom to top as follows: outer shell structure, radio frequency multilayer mixing board and antenna array.

[0009] The housing structure is rigidly fixed to the radio frequency multilayer hybrid plate, and the housing structure provides an electromagnetic shielding layer and physical support for the radio frequency multilayer hybrid plate.

[0010] The RF multilayer mixing board integrates a digital baseband module, a power conversion module, a calibration power divider network, and several single-channel RF components.

[0011] Each single-channel RF component includes a built-in RF module SIP, a power module SIP, an RF PA, a transmit filter No. 1, and a receive filter No. 1.

[0012] The radio frequency module (SIP) includes a built-in driver amplifier, transmit filter 2, switch 1, switch 3, switch 2, low-frequency noise amplifier 1, receive filter 2, and low-frequency noise amplifier 2.

[0013] The antenna array is used to radiate and receive radio frequency signals. The bottom of the antenna array is welded with an RF connector, which can be electrically interconnected with the lower RF multilayer hybrid circuit board.

[0014] Furthermore, the radio frequency multilayer hybrid board adopts a vertical layered architecture, with a core CNC layer and a core radio frequency layer arranged sequentially from bottom to top. The core CNC layer and the core radio frequency layer are connected by a prepreg and a secondary pressing process. An isolation ground plane is provided inside the radio frequency multilayer hybrid board.

[0015] The core numerical control layer carries the interconnection network of digital baseband components and power conversion components;

[0016] The core radio frequency layer integrates a calibration power divider network and radio frequency signal traces. Equally spaced shielding holes are arranged around the radio frequency signal traces to form electromagnetic shielding.

[0017] Furthermore, the RF multilayer hybrid board adopts a partitioned symmetrical structure in the horizontal direction, with several single-channel RF components symmetrically distributed on both sides of the digital baseband module and power conversion module as the center.

[0018] Each single-channel RF component measures 60×50×8mm, and all modules within each single-channel RF component are surface-mount packaged.

[0019] Furthermore, each single-channel RF component integrates a receive link, a transmit link, a power supply filter circuit, and a calibration switching branch;

[0020] The receiving link is connected to the antenna array to receive the radio frequency input signal, and performs filtering and low-noise amplification processing before sending it to the digital baseband unit to complete the signal analog-to-digital conversion and demodulation.

[0021] The digital baseband unit generates the signal to be transmitted, which is then converted from digital to analog and modulated accordingly. After filtering and power amplification through the transmission link, the signal is sent to the antenna array for outward radiation.

[0022] Furthermore, the receiving link passes through the following components sequentially from input to output: receiving filter No. 1, low-frequency noise amplifier No. 1, receiving filter No. 2, low-frequency noise amplifier No. 2, and switch No. 2.

[0023] The transmission link passes through the following components sequentially from input to output: driver amplifier, transmit filter 2, RF PA, and transmit filter 1.

[0024] The power supply filtering circuit provides a stable, low-ripple power supply for each single-channel RF component. The power supply filtering circuit includes a power supply module (SIP).

[0025] Furthermore, each single-channel RF component includes at least 5 TTL control signals;

[0026] The calibration switching branch controls switches 1 (5), 2 (12), and 3 (6) via TTL control signals to switch between the normal transceiver link mode and different calibration modes.

[0027] Furthermore, switch 1 is located in the coupling loop between the RF PA and transmit filter 1 in the transmit link, and switch 1 controls the on / off state of the transmit calibration branch;

[0028] Switch No. 2 is located after the No. 2 low-frequency noise amplifier in the receiving link. It is a single-pole triple-throw switch that controls the switching between three modes: transmit calibration branch, receive link, and receive calibration switch small loop.

[0029] Switch No. 3 is located after the calibration power divider network. It is a single-pole three-throw switch and can control the switching of three states: small circuit for receiving calibration, large circuit for receiving calibration coupling, and switch load.

[0030] Furthermore, the calibration modes include: transmit calibration branch mode, receive coupling calibration mode, and receive switch calibration mode;

[0031] In the transmit calibration branch mode, switch 1 is turned on and switch 2 is turned on to select the transmit calibration branch, which is used to obtain the calibration parameters of the transmit link;

[0032] In the receive coupling calibration mode, switch 2 selects the receive link and switch 3 selects the receive calibration coupling loop, which is used to send the standard calibration signal into the digital baseband module through the complete receive link to obtain the calibration parameters of the receive link.

[0033] In the receive switch calibration mode, switch 2 and switch 3 select the receive calibration small loop, which are used to return the standard calibration signal directly to the digital baseband module without processing by the receive link front-end module, so as to obtain the small loop reference error and separate the independent error components of the receive link front-end module.

[0034] The beneficial effects of the method described in this invention are as follows:

[0035] 1. Built-in high-precision calibration link design: This invention breaks through the design limitations of traditional external switching calibration links and innovatively adopts an integrated calibration architecture of "built-in switch + coupling detection + dynamic compensation", which completely solves the industry pain points of low calibration accuracy, large insertion loss and poor consistency in S-band. The single-pole multi-throw switch is integrated into the RF SIP module, replacing the traditional external switching switch. This reduces link nodes, lowers insertion loss by nearly 1dB, and shortens the distance between the calibration link and the transmit / receive link, reducing signal attenuation and interference and significantly improving link consistency. A built-in coupler in the transmit / receive link collects amplitude and phase information of the transmitted and received signals in real time. Combined with the standard calibration signal generated by the digital baseband, the performance differences between the RF component channels of the calibration subarray are compared and analyzed to achieve accurate calculation of calibration parameters. Multiple TTL control signals are reserved to enable rapid switching between calibration mode and normal transmit / receive mode. Calibration parameters can be dynamically adjusted based on factors such as ambient temperature and operating time to compensate for link drift. The calibration power divider network is integrated into the RF layer of the multi-layer hybrid board, using a Wilkinson power divider topology to achieve uniform distribution of the calibration signal. Its design is compatible with the main RF feed network, avoiding compatibility issues between traditional external calibration networks and the main link, and significantly simplifying the system structure.

[0036] 2. Dedicated High-Low Frequency Mixed-Pressure Multilayer Board Design: This invention employs radio frequency (RF) multilayer mixed-pressure board technology, concentrating the CNC and RF modules on the same substrate. This reduces the number of RF cables interconnecting between different board designs and significantly lowers the assembly steps and complexity of the entire phased array payload. The multilayer mixed-pressure board adopts a vertical layered architecture of "high-frequency layer + low-frequency layer" and a dual isolation design of "reference ground plane + multiple rows of metal shielding vias." Both the vertical stacking and horizontal layout effectively partition the CNC module and the multi-channel RF TR components, ensuring effective interconnection while improving isolation and shielding to avoid signal crosstalk.

[0037] 3. Miniaturized Integrated Design of S-Band: To overcome the bottleneck of miniaturization of S-band RF components, this invention adopts an integrated miniaturized design of SIP integration and high-density layout. Key components such as the receive link amplifier, transmit link driver amplifier, and built-in switching switch are integrated into a single RF SIP module (size only 21×16×3.7mm). The power supply module also adopts SIP packaging. The single-channel RF component achieves complete integration of the transmit and receive links and calibration branches within a unit size of only 60*50*8mm through only five independent surface-mount components. This maximizes the use of space and simplifies and highly integrates the design, reducing the difficulty of soldering and debugging, and adapting to the lightweight and flat payload requirements of low-Earth orbit satellites. Attached Figure Description

[0038] Figure 1 This is a schematic cross-sectional view of the phased array radio frequency system structure described in this invention;

[0039] Figure 2 This is a schematic diagram of the longitudinal stacking of the radio frequency mixing board described in this invention;

[0040] Figure 3 This is a schematic diagram of the horizontal layout of the radio frequency mixing board described in this invention;

[0041] Figure 4 This is a block diagram of the single-channel radio frequency component described in this invention;

[0042] Among them, 1-1 transmit filter, 2-RF PA, 3-2 transmit filter, 4-driver amplifier, 5-1 switch, 6-3 switch, 7-calibration power divider network, 8-1 receive filter, 9-1 low-frequency noise amplifier, 10-2 receive filter, 11-2 low-frequency noise amplifier, and 12-2 switch. Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1

[0045] This embodiment provides a mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology.

[0046] The fundamental difficulties faced by existing technologies in miniaturizing S-band calibration links stem from the combined constraints of the inherent physical path limitations of external calibration architectures, electromagnetic coupling runaway during high- and low-frequency signal mixing, and the redundancy matching requirements brought about by discrete component networking. External calibration links require additional connectors and transmission cables, resulting in significantly higher insertion losses than integrated solutions. Simultaneously, to ensure continuous transmission line impedance and avoid VSWR degradation and additional losses, strict constraints are placed on wiring configuration and spatial layout, making further volume reduction difficult. In multilayer hybrid circuit boards with digital and RF circuits co-located on the same ground plane, digital power supply noise can easily intrude into the RF path through ground plane noise conduction and near-field coupling. To block such coupling paths, a large isolation gap must be reserved in the design, making it difficult to compress the layout space and restricting the miniaturization design of the system.

[0047] Traditional external calibration networks, built using discrete couplers, switches, and attenuators, are inherently limited in amplitude and phase accuracy due to the accumulation of insertion loss, standing wave ripple, and connector repeatability errors introduced by device cascading. With high-density integration, near-field crosstalk between strong RF signals and weak calibration signals intensifies, directly impacting calibration accuracy. Furthermore, the lack of an on-chip real-time closed-loop correction mechanism for thermally induced amplitude and phase drift in devices and transmission lines further affects system amplitude and phase consistency and long-term stability. To address these challenges, this invention constructs an integrated calibration architecture with multiple built-in switches and coupled detection, achieving numerically controlled dynamic compensation. This eliminates the insertion loss uncertainty and mechanical connection failure risk introduced by long external links at their source. Simultaneously, relying on the isolated ground plane and multiple rows of metal shielded via arrays within a multi-layer hybrid pressure plate, a vertical electromagnetic isolation boundary is constructed between the RF and digital regions within a limited space, effectively suppressing parallel plate resonance, reducing ground bounce noise, and mitigating crosstalk. By combining SIP high-density integration technology with on-chip fusion of discrete matching networks, this invention achieves extreme convergence of the physical profile of the RF front-end and long-term stability of amplitude and phase consistency while ensuring calibration accuracy, precisely meeting the stringent requirements of low-Earth orbit satellite constellations for lightweight payloads and high reliability.

[0048] like Figure 1 As shown, the mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology adopts a vertically layered assembly structure, which is arranged from bottom to top as follows: shell structure, radio frequency multi-layer hybrid pressure board and antenna array.

[0049] Each layer is connected by standardized mechanical connections and RF interconnects to form a rigid whole. The outer shell structure, as the overall load-bearing base, is located at the bottom layer, providing mechanical protection, heat dissipation channels, and structural strength for the entire package structure. At the same time, the cavity formed by its metal material can act as a natural electromagnetic shielding layer, effectively suppressing the interference of the external electromagnetic environment on the internal sensitive circuits. In addition, combined with the internal metal partition structure, each RF channel is isolated, further blocking signal crosstalk between internal multi-carriers and channels.

[0050] The outer shell structure and the radio frequency multilayer hybrid platen are rigidly fixed by fastening screws and positioning stud holes in the outer shell structure. The outer shell structure provides an electromagnetic shielding layer and physical support for the radio frequency multilayer hybrid platen.

[0051] The antenna array is located at the top of the overall structure and is used to radiate and receive radio frequency (RF) signals. An RF connector is soldered to its bottom, allowing for electrical interconnection with the lower RF multilayer hybrid circuit board via SMT soldering or plug-and-play methods. Based on this structure, the signal flow of the device of this invention forms a closed loop, specifically including a transmit link and a receive link: In transmit (TX) mode, the transmit RF signal stream is generated by digital baseband components and filtered and initially amplified by the RF module SIP before being transmitted to RF PA2 for power amplification. It then passes through a filter to suppress out-of-band spurious and harmonic radiation, and is transmitted to the antenna array via the SMP connector within the RF multilayer hybrid circuit board, ultimately radiated into free space by the antenna array. In receive (RX) mode, the receive RF signal stream is captured by the antenna array and transmitted to the RF multilayer hybrid circuit board via the RF connector. It then undergoes bandpass filtering and low-noise amplification by the RF module SIP before finally being transmitted to the digital baseband components for subsequent signal demodulation and data processing.

[0052] The RF multilayer mixing board integrates a digital baseband module, a power conversion module, a calibration power divider network 7, and several single-channel RF components.

[0053] As the core electrical carrier substrate of this invention, the radio frequency multilayer hybrid board adopts a multilayer high-density interconnection process and a radio frequency-specific hybrid dielectric substrate. It integrates low-loss radio frequency transmission lines, low-noise high-isolation power distribution network and high-density digital control traces, providing full-link electrical interconnection and mechanical support for each functional module.

[0054] Example 2

[0055] This embodiment further defines the radio frequency multilayer hybrid platen in Embodiment 1.

[0056] The radio frequency multilayer hybrid circuit board adopts a high-frequency hybrid printed circuit board integrated architecture, and uses a multilayer hybrid structure. Its specific stack-up information is as follows: Figure 2As shown. The upper part is the core RF layer, which mainly integrates key RF links such as the power divider network and RF TR component signal input / output traces. The core RF layer integrates the calibration power divider network 7 and RF signal traces. Equally spaced shielding holes are arranged around the RF signal traces to form electromagnetic shielding. Due to the strict symmetry requirements of transmission line length, impedance, and path geometry, the power divider network is independently arranged on one layer, and the radiation and crosstalk effects are effectively reduced through the upper and lower ground layers and the double-row shielding hole design of the traces. This invention adopts a Wilkinson power divider topology to ensure the performance consistency and good isolation of each port, and achieves multi-channel port control through multi-stage cascading of a 1-to-2 power divider structure. Due to limitations in buried resistor materials and processes, the isolation resistor of the power divider is implemented by connecting it to the surface layer via through-holes.

[0057] The lower half is the core CNC layer, mainly containing the digital control network, power supply network, and some multiplexed TR single-channel module internal traces. This core CNC layer carries the interconnection network of digital baseband components and power conversion components. Multilayer dielectric boards are connected via high-performance prepreg, and the two core layers are tightly bonded through a secondary lamination process, ensuring interlayer bonding strength and interconnect reliability. The board material uses Panasonic's high-frequency, low-loss MEGTRON6 to meet the dual requirements of low insertion loss transmission of RF signals and high stability of digital circuits. In terms of layout design, the RF links and shielding ground layer are located at the top of the multilayer board, while the digital control and power network are integrated in the middle. The RF TR integrated module is SMT soldered to the bottom transceiver area of ​​the PCB and interconnected with the top RF network via inner layer striplines. The digital control unit is located in the non-RF projection area and connected to the middle digital layer via vias, achieving a digital-analog isolation layout. No components are laid out or soldered on the top layer of the multilayer board. Only the SMP adapter connected to the antenna array is soldered. The board adopts a full-board bare copper window design, which facilitates the efficient conduction and heat dissipation of heat from the bottom components through the PCB to the outside via the metal structure.

[0058] The radio frequency multilayer hybrid board adopts a partitioned symmetrical layout architecture, such as... Figure 3As shown, the central area houses the digital baseband and power conversion design. Several single-channel RF TR components are arranged symmetrically on both sides of the multi-layer hybrid board, with each channel's TR components concentrated within a rectangular area of ​​equal-sized units (each single-channel RF component measures 60×50×8mm). To control the number of layers and overall weight of the hybrid board, except for BGA-packaged SIP components which require interconnection via inner layer traces, other signals within a single channel component are preferentially routed on the surface layer, reducing vias and additional inner layer requirements. This optimizes board thickness while ensuring RF signal transmission performance. The signal input / output ports and control ports of the SIP are directly introduced into the corresponding inner layers of the hybrid board through metallized vias, achieving high-density interconnection. To ensure the amplitude and phase consistency of the final multi-channel RF ports, in addition to strictly controlling the process precision of the single-channel TR components, the electrical path length of the traces from the CNC 9840 chip to the output SMP adapters of each channel's TR components must be consistent in the overall hybrid board layout and routing design, thereby achieving balanced and stable multi-channel performance. The RF and digital regions are physically isolated through an isolation ground plane and multiple rows of metal shielded vias around the traces, effectively suppressing electromagnetic interference from digital control signals to the RF transceiver link and ensuring the system's electromagnetic compatibility. In terms of power supply design, the power supply lines employ a wide wire diameter design, and decoupling capacitor arrays are placed at key nodes to reduce power impedance and ripple, ensuring the stability and purity of power supply to each module. The output ports of the multi-channel RF components are directly interconnected to the antenna array via RF connector mating or SMT soldering, significantly shortening external interconnect links and reducing insertion loss and VSWR of RF signals. This invention addresses the layout and routing of RF TR components by collaboratively optimizing trace width, impedance matching, and path length based on a full-link electromagnetic simulation model, ensuring impedance continuity between functional modules and effectively reducing signal energy loss during transmission. Simultaneously, equally spaced metal shielded via arrays are arranged around the RF traces according to the simulation optimization results, forming a continuous electromagnetic shielding boundary to suppress crosstalk and unwanted radiation between traces.

[0059] Example 3

[0060] This embodiment further defines the single-channel radio frequency component in embodiments 1 and 2.

[0061] Traditional S-band RF TR components mostly use discrete components and modular splicing architecture, which generally suffer from problems such as heavy weight, large size, low integration, and complicated assembly process. Moreover, the dispersed layout of components is prone to introducing additional trace loss, impedance mismatch and channel inconsistency, making it difficult to meet the urgent needs of the new generation of phased array systems for miniaturization, lightweighting and high-density integration.

[0062] To address the aforementioned requirements, this invention features an optimized design for extreme miniaturization and high integration of single-channel RF TR components. Since the envelope size of the single-channel RF TR component needs to be within the range of 60×50×15mm, this height range is the total height limit of the entire component + PCB + structural parts. Considering the thickness of the multi-layer hybrid board and the need to reserve a certain height for the heat dissipation pad, the height of all RF components must be ensured to be below 10mm. All components within the single-channel RF component adopt surface mount packaging, achieving a low-profile structure while effectively reducing the difficulty of assembly and soldering processes. The soldering and installation of the entire board's core components can be completed in a single SMT (Surface Mount Technology) operation, effectively improving assembly efficiency and saving mass production time and costs. Key components such as the receive link amplifier and transmit link driver amplifier are integrated into a single RF SIP module, significantly reducing component size and overall weight, improving RF performance consistency between channels, and effectively avoiding additional performance losses caused by impedance mismatch during processing and assembly. The SIP package uses wire bonding for electrical interconnection, and after sintering and laser sealing of the upper and lower layers, the overall package provides excellent metal shielding. Simultaneously, the input and output ports of the receive and transmit links are directly connected to the multilayer hybrid board via BGA-packaged signal vias, with a wide port spacing. Combined with grounding solder balls around the signal vias, this further enhances transmit-receive isolation. The overall highly integrated RF SIP measures only 21×16×3.7mm. The power supply module also uses a SIP package, integrating a negative voltage protection chip and a negative voltage regulator chip, enabling 28V and 5V modulation. The 28V power supply on / off is controlled by TTL levels, and its dimensions are 10.9×6.9×2.25mm. Both passive filters employ dielectric filters for their respective frequency bands, measuring 24×9.2×8mm and 24×8.5×8mm respectively. Their metal shielding sheets must be properly grounded to ensure shielding effectiveness, stabilize the resonant mode, and guarantee filtering performance. The high-power amplifier device utilizes a metal-ceramic package with a metal heat sink at the bottom, providing excellent heat dissipation and ensuring long-term reliable operation under high-power conditions. Its dimensions are 24×17.4×4.4mm. The device integrates an impedance matching network, effectively reducing the number of external matching components, simplifying circuit design, and further improving the integration and reliability of the RF components. This achieves a balance between miniaturization, weight reduction, and high integration in the S-band TR component.

[0063] The single-channel RF component of this invention includes a power input, an RF input / output interface (SMP type, plug-in with the antenna array or SMT soldered), and five additional reserved TTL control signals (5V) for switching between the component's normal transmit / receive mode and calibration mode. The RF TR component can receive and process input RF signals from the S-band mobile communication frequency band. The signal undergoes filtering and channel selection by two stages of dielectric filters to suppress out-of-band interference and spurious signals, and amplification by two stages of low-noise amplifiers (LNAs), providing an overall signal gain of approximately 30dB. The amplified and conditioned RF signal is then output to the baseband module for subsequent analog-to-digital conversion and digital signal processing. The RF TR component can also amplify and transmit RF signals from frequency bands near the S-band mobile communication frequency band with a high peak-to-average power ratio. The signal first enters the RF SIP module, where it undergoes pre-amplification and out-of-band filtering via the internally integrated driver amplifier 4 (DA) and filter. It is then fed into a high-power amplifier for final-stage power amplification, with a peak output power exceeding 40dBm. After further suppression of spurious and harmonics by the transmitter dielectric filter, the signal is fed to the corresponding channel of the phased array antenna. The antenna element then completes the spatial electromagnetic wave radiation, achieving directional transmission and beamforming of the RF signal.

[0064] like Figure 4 As shown, in this embodiment, each single-channel RF component has a built-in RF module SIP, a power module SIP, an RF PA2, a transmit filter 1 and a receive filter 8.

[0065] The radio frequency module SIP has built-in driver amplifier 4, transmit filter 3, switch 5, switch 6, switch 12, low-frequency noise amplifier 9, receive filter 10, and low-frequency noise amplifier 11.

[0066] Each single-channel RF component integrates a receive link, a transmit link, a power supply filter circuit, and a calibration switching branch;

[0067] The receiving link is connected to the antenna array to receive the radio frequency input signal, and performs filtering and low-noise amplification processing before sending it to the digital baseband unit to complete the signal analog-to-digital conversion and demodulation.

[0068] The digital baseband unit generates the signal to be transmitted, which is then converted from digital to analog and modulated accordingly. After filtering and power amplification through the transmission link, the signal is sent to the antenna array for outward radiation.

[0069] The receiving link passes through the following components sequentially from input to output: receiving filter 8 (No. 1), low-frequency noise amplifier 9 (No. 1), receiving filter 10 (No. 2), low-frequency noise amplifier 11 (No. 2), and switch 12 (No. 2).

[0070] The transmission link passes sequentially from input to output through driver amplifier 4, transmit filter 3 (number 2), RF PA2, and transmit filter 1 (number 1).

[0071] The power supply filtering circuit provides a stable, low-ripple power supply for each single-channel RF component. The power supply filtering circuit includes a power supply module (SIP).

[0072] Each single-channel RF component includes at least 5 TTL control signals;

[0073] The calibration switching branch controls three switches via TTL control signals to switch between the normal transmit / receive link mode and different calibration modes.

[0074] Switch 5 is located in the coupling loop between RF PA2 and transmit filter 1 in the transmit link. Switch 5 controls the on / off state of the transmit calibration branch. When the transmit calibration branch is on, the transmit link is on by default.

[0075] Switch 12 is located after low-frequency noise amplifier 11 in the receiving link. It is a single-pole triple-throw switch that can control the switching between three modes: transmit calibration branch, receive link, and receive calibration switch small loop.

[0076] Switch 6, number 3, is located after the calibration power divider network 7. It is a single-pole three-throw switch that can control the switching between three states: small circuit for receiving calibration switch, large circuit for receiving calibration coupling, and switch load.

[0077] The calibration modes include: transmit calibration branch mode, receive coupling calibration mode, and receive switch calibration mode.

[0078] In the transmit calibration branch mode, switch 5 of switch 1 is turned on and switch 12 of switch 2 is turned on to select the transmit calibration branch, which is used to obtain the calibration parameters of the transmit link;

[0079] In the receive coupling calibration mode, switch 12 of switch 2 selects the receive link and switch 6 of switch 3 selects the receive calibration coupling loop, which is used to send the standard calibration signal to the digital baseband module through the complete receive link to obtain the calibration parameters of the receive link.

[0080] In the receive switch calibration mode, switch 12 of switch 2 and switch 6 of switch 3 select the receive calibration small loop. This is used to return the standard calibration signal directly to the digital baseband module without processing by the receive link front-end module, so as to obtain the small loop reference error and separate the independent error components of the receive link front-end module.

[0081] The transmit calibration branch includes: digital baseband module, switch 12 (No. 2), and switch 5 (No. 1);

[0082] The receiving calibration switch loop includes: digital baseband module, calibration power divider network 7, switch 3 6 and switch 2 12;

[0083] The large receiving calibration coupling loop includes: digital baseband module, calibration power divider network 7, switch 3 6, low-frequency noise amplifier 1 9, receiving filter 2 10, low-frequency noise amplifier 2 11, and switch 2 12.

[0084] Example 4

[0085] This embodiment provides a triggering method for different calibration modes, which is triggered by a TTL control signal.

[0086] In this example, the triggering methods for different calibration modes and the working process of each calibration mode are as follows:

[0087] When switch 5 (control signal C1) is set to 1 and switch 2 (control signals C2 and C3) is set to 10, the transmit calibration branch mode is triggered. In the transmit calibration branch mode, the transmit coupling loop of each single-channel RF component couples the transmit link output signal and outputs it to the digital baseband component through switch 5 (1) and switch 12 (2) in sequence. This is used to determine the actual transmit signal power of each single-channel RF component. The digital baseband component compares the actual transmit signal power with the transmit standard signal power emitted by the digital baseband component to obtain the transmit calibration parameters.

[0088] The transmit coupling circuit is set between transmit filter 1 and RF PA2. Transmit filter 1 is used to suppress out-of-band unwanted signals. The transmit coupling circuit is connected to switch 5.

[0089] When control signals C2 and C3 of switch 12 are set to 11 and control signals C4 and C5 of switch 6 are set to 00, the receive coupling calibration mode is triggered. In the receive coupling calibration mode, the digital baseband components send a calibration signal, which is sent to the receive link sequentially through the calibration power divider network 7, switch 6 of 3, and the receive coupling circuit. After being processed by the receive link, the calibration signal is output to the digital baseband components through switch 12 to determine the actual received signal power of each single-channel RF component. The digital baseband components compare the actual received signal power with the calibration signal power sent by the digital baseband components to obtain the receive calibration parameters.

[0090] The receiving coupling circuit is set between receiving filter 8 and low-noise amplifier 2. Receiving filter 8 is used for receiving filter 8. The receiving coupling circuit is connected to switch 6.

[0091] When control signals C2 and C3 of switch 12 are set to 01 and control signals C4 and C5 of switch 6 are set to 10, the receiver switch calibration mode is triggered. In the receiver switch calibration mode, the digital baseband components emit calibration signals, which pass through the calibration power divider network 7, switch 6 of 3, and switch 12 of 2 in sequence, and return directly to the digital baseband components. The calibration signals do not pass through the receiver coupling loop and the receiver link front-end amplification and filtering processing, and are used to clarify the measured signals of the small loop between switch 6 of 3 and switch 12 of 2. The digital baseband components compare the measured signals of the small loop with the emitted calibration signals to obtain the small loop reference error parameters. The small loop reference error parameters are subtracted from the receiver calibration parameters obtained in the receiver coupling calibration mode to separate the error components of the receiver coupler and the receiver link.

[0092] Compared to existing design methods, this invention achieves maximum space utilization by highly integrating the complete RF transceiver link and calibration branch into a single-channel TR component of 60×50×8mm. This significantly simplifies the overall component structure and peripheral interconnect design, effectively solving the problems of scattered links, low space utilization, and cumbersome assembly in existing designs. Combined with SIP integrated packaging and chip-based device selection, the core components inside the component are highly integrated and miniaturized, controlling the total weight of the single-channel components to 30g. This meets the lightweight and flattened application requirements of low-Earth orbit satellites, providing strong support for lightweight deployment, efficient space utilization, and engineering installation of phased array RF systems. The built-in calibration link design integrates the calibration branch and RF transceiver link within the component, eliminating the need for additional external calibration modules and interconnect cables, reducing link insertion loss and external electromagnetic interference, and improving efficiency from an architectural perspective. The system enhances the stability and anti-interference capabilities of the calibration link. Simultaneously, it achieves efficient dynamic compensation for performance deviations in each channel through reserved TTL control signals and coupling detection loops, improving calibration accuracy and addressing the pain points of poor consistency and low accuracy in traditional calibration links. This ensures amplitude and phase consistency of multi-channel RF TR components, adapting to high-precision beamforming requirements. Furthermore, relying on RF multilayer hybrid board integration technology, it integrates RF transceiver, amplitude and phase control, signal conditioning, and power management functions into a single board, achieving a fully integrated subarray-level design. This eliminates the need for numerous external RF cables, adapters, and interconnect leads between traditional discrete modules. Signal transmission is completed through vertical interconnection and planar wiring within the board, significantly shortening the RF path, reducing link insertion loss and signal reflection, and greatly improving signal transmission purity and channel consistency. This effectively meets the stringent requirements of long-distance, high-sensitivity, and low-latency transmission for direct communication between low-orbit satellite phones. In addition, the high-density co-board integration of the CNC module and the RF front-end simplifies the system architecture and assembly process, reduces manual assembly steps and assembly errors, improves product consistency and reliability, significantly reduces mass production costs and production difficulty, and adapts to the engineering mass production needs of low-orbit communication satellite mobile phones directly connected to phased arrays.

Claims

1. A mobile phone direct-connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology, characterized in that, The phased array radio frequency system adopts a vertically layered assembly structure, which is arranged from bottom to top as follows: outer shell structure, radio frequency multilayer mixing board and antenna array. The housing structure is rigidly fixed to the radio frequency multilayer hybrid plate, and the housing structure provides an electromagnetic shielding layer and physical support for the radio frequency multilayer hybrid plate. The radio frequency multilayer hybrid board integrates a digital baseband module, a power conversion module, a calibration power divider network (7), and several single-channel radio frequency components. Each single-channel RF component has a built-in RF module SIP, a power module SIP, an RF PA (2), a transmit filter (1) and a receive filter (8). The radio frequency module SIP has a built-in driver amplifier (4), a transmit filter (3) No. 2, a switch (5) No. 1, a switch (6) No. 3, a switch (12) No. 2, a low-frequency noise amplifier (9) No. 1, a receive filter (10) No. 2, and a low-frequency noise amplifier (11). The antenna array is used to radiate and receive radio frequency signals. The bottom of the antenna array is welded with an RF connector, which can be electrically interconnected with the lower RF multilayer hybrid circuit board.

2. The mobile phone direct-connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 1, characterized in that, The radio frequency multilayer hybrid board adopts a vertical layered architecture, with a core CNC layer and a core radio frequency layer arranged sequentially from bottom to top. The core CNC layer and the core radio frequency layer are connected by a prepreg and a secondary pressing process. An isolation ground plane is provided inside the radio frequency multilayer hybrid board. The core numerical control layer carries the interconnection network of digital baseband components and power conversion components; The core radio frequency layer integrates a calibration power divider network (7) and radio frequency signal traces. Equally spaced shielding holes are arranged around the radio frequency signal traces to form electromagnetic shielding.

3. The mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 2, characterized in that, The radio frequency multilayer hybrid board adopts a partitioned symmetrical structure in the horizontal direction, with several single-channel radio frequency components symmetrically distributed on both sides of the digital baseband module and power conversion module as the center. Each single-channel RF component measures 60×50×8mm, and all modules within each single-channel RF component are surface-mount packaged.

4. The mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 3, characterized in that, Each single-channel RF component integrates a receive link, a transmit link, a power supply filter circuit, and a calibration switching branch; The receiving link is connected to the antenna array to receive the radio frequency input signal, and performs filtering and low-noise amplification processing before sending it to the digital baseband unit to complete the signal analog-to-digital conversion and demodulation. The digital baseband unit generates the signal to be transmitted, which is then converted from digital to analog and modulated accordingly. After filtering and power amplification through the transmission link, the signal is sent to the antenna array for outward radiation.

5. The mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 4, characterized in that, The receiving link passes through the following components in sequence from input to output: receiving filter 1 (8), low-frequency noise amplifier 1 (9), receiving filter 2 (10), low-frequency noise amplifier 2 (11), and switch 2 (12). The transmission link passes through the following components sequentially from input to output: driver amplifier (4), transmission filter 2 (3), RF PA (2), and transmission filter 1 (1). The power supply filtering circuit provides a stable, low-ripple power supply for each single-channel RF component. The power supply filtering circuit includes a power supply module (SIP).

6. The mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 5, characterized in that, Each single-channel RF component includes at least 5 TTL control signals; The calibration switching branch controls switch 1 (5), switch 2 (12), and switch 3 (6) respectively via TTL control signals to achieve switching between the normal transceiver link mode and different calibration modes.

7. The mobile phone direct-connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 6, characterized in that, Switch 1 (5) is located in the coupling loop between the RF PA (2) of the transmit link and the transmit filter (1). Switch 1 (5) controls the on / off state of the transmit calibration branch. Switch No. 2 (12) is located after the No. 2 low-frequency noise amplifier (11) in the receiving link. It is a single-pole triple-throw switch that controls the switching between three modes: transmit calibration branch, receive link, and receive calibration switch small loop. Switch No. 3 (6) is set after the calibration power divider network (7). It is a single-pole three-throw switch that can control the switching of three states: small circuit of receiving calibration switch, large circuit of receiving calibration coupling, and switch load.

8. The mobile phone direct connection S-band phased array radio frequency system based on multi-layer hybrid pressure board technology according to claim 7, characterized in that, The calibration modes include: transmit calibration branch mode, receive coupling calibration mode, and receive switch calibration mode. In the transmit calibration branch mode, switch 1 (5) is turned on and switch 2 (12) is turned on to select the transmit calibration branch to obtain the calibration parameters of the transmit link; In the receive coupling calibration mode, switch 2 (12) selects the receive link and switch 3 (6) selects the receive calibration coupling loop, which is used to send the standard calibration signal into the digital baseband module through the complete receive link to obtain the calibration parameters of the receive link; In the receiving switch calibration mode, switch 2 (12) selects the receiving calibration small loop and switch 3 (6) selects the receiving calibration small loop. This is used to return the standard calibration signal directly to the digital baseband module without processing by the receiving link front-end module, so as to obtain the small loop reference error and to separate the independent error components of the receiving link front-end module.

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