FPGA-based 10-channel RS422 to UWB interface conversion terminal and conversion method

Abstract

This invention proposes a 10-channel RS422 to UWB interface conversion terminal and conversion method based on FPGA, belonging to the field of satellite wireless communication technology. It solves the problem that existing RS422 to UWB interface conversion terminals cannot achieve simultaneous full-duplex transmission of multiple RS422 interfaces. The conversion terminal includes: an RS-422 terminal module, an interface conversion module, a UWB module, and a power supply module. The RS-422 interface module is used to convert RS422 differential signals to and from TTL level single-ended signals. The conversion interface module is used to split and synthesize TTL level single-ended signals. The UWB module receives the synthesized TTL level single-ended signal, converts it to a UWB signal, and transmits it through a UWB antenna. The power supply module supplies power to the RS422 interface chip, the main controller, and the DW1000 chip.

Description

Technical Field

[0001] This invention relates to an FPGA-based 10-channel RS422 interface to UWB interface conversion terminal and conversion method, belonging to the field of satellite wireless communication technology. Background Technology

[0002] In recent years, with the increasing demand for space exploration, the number and types of payloads have gradually increased. Furthermore, the hardware interfaces and transmission rates of these payloads vary, making testing and experimentation difficult. Traditional satellite data distribution mostly uses wired data interfaces or systems, such as the 1553B, CAN, SpaceWire standard bus, and RS422. Most of these communication standards use redundant cables to improve reliability, thus increasing the complexity and quality of satellite wiring harnesses. Meanwhile, wireless communication technology is developing rapidly, and its cableless and easy-to-maintain characteristics make it highly suitable for testing and experimentation. The aforementioned redundancy design has a significant impact on spacecraft quality, assembly, and testing. Therefore, using wireless communication within the satellite module can effectively solve the problem of different transmission rates due to different hardware interfaces, effectively improving joint debugging efficiency.

[0003] RS422 stands for "Electrical Characteristics of Balanced Voltage Digital Interface Circuits." This standard evolved from RS232, offering significantly improved transmission speed and distance compared to RS232. Furthermore, because RS422 employs balanced drive and differential signal transmission, it solves the level offset problem inherent in RS232's single-ended transmission, exhibiting high common-mode rejection ratio and strong anti-interference capabilities. Therefore, the RS422 standard is widely used in the design of serial communication interfaces.

[0004] UWB (Ultra Wide Band) is an ultra-wideband wireless communication technology. Its essential difference from conventional communication systems lies in its use of nanosecond-level narrow pulses to transmit data. Therefore, compared with narrowband systems, UWB technology has significant advantages such as stronger anti-interference capabilities, higher transmission rates, wider bandwidth, lower power consumption, better security, and higher positioning accuracy.

[0005] The RS-422 interface to UWB interface conversion terminal enables short-range wireless communication of satellite payloads, which can effectively improve the flexibility and adaptability of satellite communication, reduce cable weight, and save costs. This project has high application value and practical significance.

[0006] The shortcomings and deficiencies of existing technologies are as follows: 1. In the current domestically designed RS422 to UWB interface conversion terminal, the aerospace single machine A sends the RS422 signal to the wireless transmission system. The core processing unit MCU of the wireless transmission system converts the RS422 signal into a UWB signal, and then conducts intra-cabin wireless communication through the UWB antenna. This design requires one wireless transmission system for each of the multiple RS422 interfaces, resulting in high cost and complex structure. 2. Currently, the RS422 to UWB interface conversion terminal designed abroad uses the domestically designed VN360 UWB module. The controller of this module is the STM32L486, a single-core microcontroller based on the ARM Cortex-M4 core. It does not have parallel processing capabilities. Similarly, when facing multiple RS422 interfaces, only one VN360 UWB module can be used for each channel, resulting in high cost and complex structure.

[0007] In summary, there is currently no good design solution for an RS422 interface to UWB interface conversion terminal that requires simultaneous full-duplex transmission of multiple RS422 interfaces. Summary of the Invention

[0008] To address the problem that existing RS422 to UWB interface conversion terminals cannot achieve simultaneous full-duplex transmission of multiple RS422 interfaces, this invention proposes a 10-channel RS422 to UWB interface conversion terminal and conversion method based on FPGA.

[0009] The technical solution adopted by this invention to solve the above problems is as follows: The FPGA-based 10-channel RS422 interface to UWB interface conversion terminal proposed in this invention includes:

[0010] RS-422 terminal module, interface conversion module, UWB module and power supply module;

[0011] The RS-422 interface module is used to convert RS422 differential signals to TTL level single-ended signals.

[0012] The conversion interface module is used to split and synthesize TTL level single-ended signals;

[0013] The UWB module is used to receive a synthesized single-ended TTL level signal and convert it into a UWB signal, and then transmit the data through a UWB antenna.

[0014] The power module is used to power the RS422 interface chip, the main controller, and the DW1000 chip.

[0015] Preferably, the RS-422 terminal module includes 10 RS422 channels and 20 RS422 interface chips. The RS422 interface chips are used to convert 10 RS422 differential signals received from the 10 RS422 channels into TTL level single-ended signals, and to convert the 10 split TTL level single-ended signals into RS422 differential signals and input them into the corresponding 10 RS422 channels.

[0016] Preferably, the interface conversion module includes a main controller, a combiner, and a splitter;

[0017] The main controller uses an FPGA chip to design the control logic for the combiner and splitter;

[0018] The combiner is used to combine 10 single-ended TTL level signals into 1 TTL level signal;

[0019] The splitter is used to split one TTL level signal into ten TTL level signals.

[0020] Preferably, the UWB module includes a DW1000 chip and a UWB antenna;

[0021] The DW1000 chip is connected to the host controller via the SPI bus and is used to convert TTL level single-ended signals into UWB signals.

[0022] UWB antennas are used for data transmission between UWB modules.

[0023] A method for converting 10 RS422 interfaces to UWB interfaces based on FPGA, including:

[0024] Step 1: The first RS422 terminal module receives 10 RS422 differential signals from 10 RS422 channels, which are converted into TTL level single-ended signals by the RS422 interface chip IL422E. The 10 TTL level single-ended signals are then input to the first interface conversion module.

[0025] Step 2: Using the combiner logic designed in the FPGA chip of the first interface conversion module, the 10 TTL level single-ended signals are combined into 1 TTL level single-ended signal, and the combined 1 TTL level single-ended signal is input into the DW1000 chip of the first UWB module through the SPI bus.

[0026] Step 3: The DW1000 chip converts the received TTL level single-ended signal into a UWB signal, and then transmits the UWB signal through the UWB antenna in the second UWB module;

[0027] Step 4: The DW1000 chip in the second UWB module receives the transmitted UWB signal, converts the UWB signal into a single-ended TTL level signal, and inputs it into the second interface conversion module.

[0028] Step 5: Using the splitter logic designed in the FPGA chip of the second interface conversion module, the 1 TTL level single-ended signal is split into 10 TTL level single-ended signals. The 10 TTL level single-ended signals are input to the second RS422 terminal module and converted into RS422 differential signals by the RS422 interface chip, which are then input to the corresponding 10 RS422 channels to complete the single-ended signal conversion.

[0029] Step 6: Following the logic in Steps 1-5, the 10 RS422 differential signals are input to the second interface conversion module via the second RS422 terminal module and synthesized into one TTL level single-ended signal. Then, they are input to the first interface conversion module via the second UWB module and the first UWB module and split into 10 TTL level single-ended signals. Finally, the 10 TTL level single-ended signals are input to the first RS422 terminal module and converted into RS422 differential signals, which are then input to the corresponding 10 RS422 channels, thus completing the single-ended signal conversion.

[0030] Step 7: Repeat steps 1-6 to perform fast transmit / receive switching of the RS422 terminal module to achieve full-duplex transmission.

[0031] The beneficial effects of this invention are:

[0032] (1) By controlling the working mode of DW1000, the present invention can achieve full-duplex transmission with good performance.

[0033] (2) This invention uses an FPGA as the main control chip, which has strong processing capabilities and excellent processing capabilities for multiple RS422 interfaces. Specifically, it employs a combiner and splitter design to combine multiple RS422 signals into a single TTL level single-ended signal or split a single TTL level single-ended signal into multiple RS422 signals, and can simultaneously support the mutual conversion between up to 10 RS422 and UWB signals. Only one FPGA chip is needed for 10 RS422 signals, resulting in lower space and price costs. Attached Figure Description

[0034] Figure 1 A structural block diagram of the FPGA-based 10-channel RS422 interface to UWB interface conversion terminal provided by the present invention;

[0035] Figure 2 A schematic diagram of an RS422 interface to UWB interface conversion terminal designed in China for the background technology;

[0036] Figure 3 A schematic diagram of the VN 360 module structure, an RS422 interface to UWB interface conversion terminal designed for use in China and abroad, is shown in the background technology.

[0037] Figure 4 A schematic diagram of the structure of an RS422 interface to UWB interface conversion terminal designed for use in China and abroad, as shown in the background technology.

[0038] Figure 5 A flowchart illustrating the FPGA-based 10-channel RS422 interface to UWB interface conversion method provided by this invention. Detailed Implementation

[0039] Specific implementation method one: Combining Figure 1-4 This implementation method is described as follows: Figure 1 As shown, the structure of the FPGA-based 10-channel RS422 interface to UWB interface conversion terminal described in this embodiment includes:

[0040] RS-422 terminal module, interface conversion module, UWB module and power supply module;

[0041] In this embodiment, the circuit is powered by DC 28V. The RS-422 interface module includes: 10 RS422 channels and 20 RS422 interface chips IL422E, which are used to convert RS422 differential signals to TTL level single-ended signals.

[0042] The interface conversion module includes a main controller, a combiner, and a splitter. The main controller uses an FPGA chip XC7Z020-2CLG400I, which has high programmability and flexibility, supports Verilog hardware description language, and can implement the functions of the combiner and the classifier. The combiner combines the 10 single-ended TTL level signals into 1 TTL level signal, and the splitter splits the 1 TTL level signal into 10 TTL level signals.

[0043] The UWB module includes a DW1000 chip and a UWB antenna. The DW1000 chip is connected to the main controller via an SPI bus and transmits UWB signals through the UWB antenna. The UWB antenna is also used for data transmission between UWB modules.

[0044] The power supply section uses a 28V to 5V DC-DC converter J10W24S05A, a 5V to 3.3V DC-DC converter TPS74401RGWT, an AMS1117-3.3, a 5V to 1.8V DC-DC converter AMS1117-1.8, and an isolation input chip DCR010505P, which are used to power the RS422 interface chip IL422E, the FPGA, and the DW1000 chip, respectively.

[0045] In this embodiment, the FPGA circuit consists of an XC7Z020-2CLG400I and simple peripheral circuits. The FPGA is equipped with 12 RS422 buses, 1 SPI bus, and 1 JTAG interface. The FPGA is powered by DC 3.3V and has 114 general-purpose I / O ports, which can well realize the design requirements proposed in this invention.

[0046] In this embodiment, the RS422 terminal module circuit consists of one J30JA-66ZKW-J transceiver, five DCR010505P transceivers, ten IL422E transceivers, and simple peripheral circuitry. The J30JA-66ZKW-J is a 66-pin connector used to connect ten RS422 channels, transmitting the ten RS422 data to the IL422E. The IL422E is an electrically isolated high-speed differential bus transceiver that can convert RS422 differential signals into TTL level single-ended signals. The DCR010505P is a high-efficiency, input-isolated, output-regulated DC-DC converter with high precision and low noise.

[0047] In this embodiment, the UWB module consists of one DW1000 chip, one HHM1595A1, one SMA, and simple peripheral circuitry. The DW1000 chip is a UWB RF signal transceiver chip with an SPI slave interface, offering advantages such as high integration, low power consumption, and low cost. The HHM1595A1 is a multi-layer balun, primarily used in the 3GHz to 8GHz frequency range, meeting the design requirements of this invention. The SMA is an ultra-small coaxial cable connector widely used in the RF and microwave industries; when connected to a UWB antenna, it can transmit UWB signals.

[0048] In this embodiment, the power supply section consists of one J10W24S05A, two TPS74401RGWT, one AMS1117-3.3, one AMS1117-1.8, and peripheral circuitry. The J10W24S05A is an ultra-wide voltage input 10W isolated regulated DC-DC module power supply, meeting the 28V voltage input requirement of this design. The TPS74401RGWT is a single-output low-dropout regulator with the advantage of fast transient response. The AMS1117-3.3 and AMS1117-1.8 are both low-dropout linear regulators, both featuring low quiescent current, low voltage drop, high output current, and thermal shutdown protection.

[0049] Through and Figure 2-4 Compared with the prior art, the present invention requires only one FPGA chip for 10 RS422 signals, and can simultaneously support the mutual conversion between up to 10 RS422 and UWB signals. It has strong processing capabilities and low space and price costs, and solves the problem that the prior art cannot achieve simultaneous full-duplex transmission of multiple RS422 interfaces.

[0050] Specific Implementation Method Two: Combining Figure 5 This embodiment will be described as follows: Figure 5 As shown, the FPGA-based 10-channel RS422 interface to UWB interface conversion method described in this embodiment includes:

[0051] S1: The first RS422 terminal module receives 10 RS422 differential signals from 10 RS422 channels respectively, converts them into TTL level single-ended signals via RS422 interface chip IL422E, and inputs the 10 TTL level single-ended signals into the first interface conversion module.

[0052] S2: Through the combiner logic designed in the FPGA chip of the first interface conversion module, 10 TTL level single-ended signals are combined into 1 TTL level single-ended signal, and the combined 1 TTL level single-ended signal is input to the DW1000 chip of the first UWB module through the SPI bus;

[0053] S3: The DW1000 chip converts the received TTL level single-ended signal into a UWB signal, and transmits the UWB signal through the UWB antenna in the second UWB module;

[0054] S4: The DW1000 chip in the second UWB module receives the transmitted UWB signal, converts the UWB signal into a single-ended TTL level signal through the DW1000 chip in the second UWB module, and inputs it into the second interface conversion module;

[0055] S5: Through the splitter logic designed in the FPGA chip of the second interface conversion module, the 1 TTL level single-ended signal is split into 10 TTL level single-ended signals. The 10 TTL level single-ended signals are input to the second RS422 terminal module and converted into RS422 differential signals by the RS422 interface chip and input to the corresponding 10 RS422 channels, thus completing the single-ended signal conversion.

[0056] S6: According to the logic in S1-S5, the 10 RS422 differential signals are input to the second interface conversion module via the second RS422 terminal module and synthesized into 1 TTL level single-ended signal. Then, they are input to the first interface conversion module via the second UWB module and the first UWB module and split into 10 TTL level single-ended signals. The 10 TTL level single-ended signals are input to the first RS422 terminal module and converted into RS422 differential signals via the RS422 interface chip and input to the corresponding 10 RS422 channels, thus completing the single-ended signal conversion.

[0057] S7: Repeat S1-S6 to perform fast transmit / receive switching of the RS422 terminal module to achieve full-duplex transmission.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A 10-channel RS422 interface to UWB interface conversion terminal based on FPGA, characterized in that, The structure of the FPGA-based 10-channel RS422 interface to UWB interface conversion terminal includes: RS-422 terminal module, interface conversion module, UWB module and power supply module; The RS-422 terminal module is used to convert RS422 differential signals to TTL level single-ended signals. The RS-422 terminal module includes 10 RS422 channels and 20 RS422 interface chips. The RS422 interface chips are used to convert the 10 RS422 differential signals received from the 10 RS422 channels into TTL level single-ended signals, and to convert the 10 split TTL level single-ended signals into RS422 differential signals and input them into the corresponding 10 RS422 channels. The interface conversion module is used to split and synthesize TTL level single-ended signals; The interface conversion module includes a main controller, a combiner, and a splitter; The main controller uses an FPGA chip to design the control logic for the combiner and splitter; The combiner is used to combine 10 single-ended TTL level signals into 1 TTL level signal; The splitter is used to split one TTL level signal into ten TTL level signals; The UWB module is used to receive a synthesized single-ended TTL level signal and convert it into a UWB signal, and then transmit the data through a UWB antenna. The UWB module includes a DW1000 chip and a UWB antenna; The DW1000 chip is connected to the host controller via the SPI bus and is used to convert TTL level single-ended signals into UWB signals. The UWB antenna is used for data transmission between UWB modules; The power module is used to supply power to the RS422 interface chip, the main controller, and the DW1000 chip.

2. A method for converting 10 RS422 interfaces to UWB interfaces based on FPGA, applied to the 10 RS422 interface to UWB interface conversion terminal based on FPGA as described in claim 1, characterized in that, include: Step 1: The first RS422 terminal module receives 10 RS422 differential signals from 10 RS422 channels, which are converted into TTL level single-ended signals by the RS422 interface chip IL422E. The 10 TTL level single-ended signals are then input to the first interface conversion module. Step 2: Using the combiner logic designed in the FPGA chip of the first interface conversion module, the 10 TTL level single-ended signals are combined into 1 TTL level single-ended signal, and the combined 1 TTL level single-ended signal is input into the DW1000 chip of the first UWB module through the SPI bus. Step 3: The DW1000 chip converts the received TTL level single-ended signal into a UWB signal, and then transmits the UWB signal through the UWB antenna in the second UWB module; Step 4: The DW1000 chip in the second UWB module receives the transmitted UWB signal, converts the UWB signal into a single-ended TTL level signal, and inputs it into the second interface conversion module. Step 5: Using the splitter logic designed in the FPGA chip of the second interface conversion module, the 1 TTL level single-ended signal is split into 10 TTL level single-ended signals. The 10 TTL level single-ended signals are input to the second RS422 terminal module and converted into RS422 differential signals by the RS422 interface chip, which are then input to the corresponding 10 RS422 channels to complete the single-ended signal conversion. Step 6: Following the logic in Steps 1-5, the 10 RS422 differential signals are input to the second interface conversion module via the second RS422 terminal module and synthesized into one TTL level single-ended signal. Then, they are input to the first interface conversion module via the second UWB module and the first UWB module and split into 10 TTL level single-ended signals. Finally, the 10 TTL level single-ended signals are input to the first RS422 terminal module and converted into RS422 differential signals, which are then input to the corresponding 10 RS422 channels, thus completing the single-ended signal conversion. Step 7: Repeat steps 1-6 to perform fast transmit / receive switching of the RS422 terminal module to achieve full-duplex transmission.

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