Unmanned aerial vehicle data unvarnished transmission device and unvarnished transmission method based on LWIP protocol stack

Abstract

The invention discloses an unmanned aerial vehicle data unvarnished transmission device and unvarnished transmission method based on an LWIP protocol stack, and particularly relates to the field of unmanned aerial vehicle communication. Comprising the following steps: receiving an uplink data packet of a ground end, sending the uplink data packet to a protocol stack for processing, converting the uplink data packet into an uplink wireless signal, and sending the uplink wireless signal to a target unmanned aerial vehicle; receiving a downlink wireless signal of the target unmanned aerial vehicle, sending the downlink wireless signal to the protocol stack to be processed into a downlink data packet, and sending the downlink data packet to the ground end; the processing process of the protocol stack comprises the following steps: transmitting a received data packet to the protocol stack through a wired physical layer or a wireless physical layer, receiving or forwarding the data packet through a network layer, and encapsulating or de-encapsulating the received data packet through a transmission layer and an application layer; and the controller transmits the packaged data packet to the target unmanned aerial vehicle and transmits the de-packaged data packet to the ground end. The time edge of data transmission is reduced, and the transmission efficiency of the unvarnished transmission equipment is improved.

Description

Technical Field

[0001] The present application relates to the field of drone communications, and in particular to a drone data transparent transmission device and method based on the LWIP protocol stack. Background Art

[0002] In drone data communication equipment, data transmission rate, transmission distance, bit error rate, etc. are usually the key technical indicators of drone communication equipment. As these technologies become more mature, indicators such as the versatility, latency, and user-friendliness of communication equipment are becoming more and more the focus of users.

[0003] Generally speaking, in a UAV system, when the ground-end measurement and control station sends remote control commands to the airborne UAV through the UAV communication equipment, the communication equipment needs to agree on the interface data transmission frame protocol with the ground-end measurement and control computer and the airborne flight control computer respectively, and transmit strictly in accordance with the agreed frame protocol, resulting in reduced user-friendliness. At the same time, the UAV communication equipment has wired ports and wireless ports. The data processing of the wired port follows the standard network protocol stack TCP / IP, and the data processing of the wireless port has no standard protocol stack due to the complexity and particularity of the wireless channel. When performing data connection communication testing and routing forwarding between devices, it is necessary to wait until the data reaches the application layer to determine the type of data, and then decide whether to directly process or route the data based on the data type, resulting in reduced versatility of the data link and increased transmission delay. Summary of the invention

[0004] The main purpose of this application is to provide a UAV data transparent transmission device and method based on the LWIP protocol stack, aiming to solve the problem of increased transmission delay in existing transmission methods.

[0005] To achieve the above-mentioned purpose, the present application provides a UAV data transmission device based on the LWIP protocol stack, including: a network interface unit, connected to the ground end, for receiving uplink data packets from the ground end; a controller, connected to the network interface unit, for sending the uplink data packets to the protocol stack for encapsulation processing, and processing the encapsulated data packets into baseband signals; a radio frequency interface unit, connected to the controller, for converting the baseband signal into a radio frequency signal; a transceiver component, connected to the radio frequency interface unit and the antenna, for preprocessing the radio frequency signal, and converting it into an uplink wireless signal to send to the target UAV; it is also used to receive the downlink wireless signal of the target UAV, and convert the downlink wireless signal into a radio frequency signal; the radio frequency interface unit is also used to convert the radio frequency signal into a baseband signal; the controller is also used to process the baseband signal into a digital signal, and send it to the protocol stack for decapsulation processing to obtain a downlink data packet; the network interface unit is also used to send a downlink data packet to the ground end.

[0006] To achieve the above-mentioned purpose, the present application also provides a method for transparent transmission of drone data based on the LWIP protocol stack, which adopts the above-mentioned transparent transmission device, and the method includes: receiving an uplink data packet from the ground end through a network interface unit, and the controller sends the uplink data packet to the protocol stack for processing, and converts the processed data packet into an uplink wireless signal through a radio frequency interface unit and a transceiver component in turn, and sends it to the target drone; receiving a downlink wireless signal from the target drone through the transceiver component, and converting the downlink wireless signal into a digital signal through a radio frequency interface unit and a controller in turn, and sending it to the protocol stack for processing into a downlink data packet, and sending it to the ground end; wherein the protocol stack includes a wired physical layer, a wireless physical layer, a network interface layer, a network layer, a transmission layer, and a wireless communication layer. The processing process of the protocol stack includes: configuring the wired physical layer for the network interface unit through the controller; configuring the wireless physical layer for the radio frequency interface unit through the controller; setting the wireless network interface driver function in the network interface layer; allocating the information of its own device to the wireless network interface, adding the wireless network interface to the network interface layer linked list, and setting the wireless network interface as the default destination network in the routing table; transmitting the received data packet to the protocol stack through the wired physical layer or the wireless physical layer, receiving or forwarding the data packet through the network layer, and encapsulating or decapsulating the received data packet through the transport layer and the application layer; the controller transmits the encapsulated data packet to the target drone, and transmits the decapsulated data packet to the ground end.

[0007] Optionally, the information includes an IP address, a physical address, and a data receiving callback function; the network layer receives or forwards the data packet, including: when it is determined that the data packet is of the ARP data type and the destination address of the current data frame is the IP address of its own device, the IP address and physical address of its own device form a reply frame, and a unicast reply is performed according to the physical layer source of the data packet; when it is determined that the data packet is an ARP request data packet and the destination address of the current request data packet is not the IP address of its own device, the destination address of the request data packet is searched in the routing table and then routed and forwarded.

[0008] Optionally, receiving or forwarding a data packet at the network layer also includes: when it is determined that the data packet is an IP data packet and the destination address of the current IP frame is the IP address of its own device, passing it upward to the transport layer and the application layer; when it is determined that the destination address of the data packet is not the IP address of its own device, routing and forwarding the data packet.

[0009] Optionally, configuring the wired physical layer for the network interface unit through the controller includes: the controller performs read and write operations on a register of the network interface unit through an MDIO interface to obtain register parameters of the network interface unit.

[0010] Optionally, the register read and write parameters of the network interface unit include configurations of the working mode and the interface mode.

[0011] Optionally, configuring the wireless physical layer for the radio frequency interface unit through the controller includes: the controller performs read and write operations on registers of the wireless physical layer and the radio frequency interface unit through an SPI interface to obtain register parameters of the radio frequency interface unit.

[0012] Optionally, the register parameters of the radio frequency interface unit include radio frequency channel, sampling rate, bandwidth, frequency and working mode.

[0013] Compared with the prior art, the beneficial effects of this application are as follows: The UAV data transparent transmission device based on the LWIP protocol stack of the present invention sends an uplink data packet to the protocol stack through a controller, receives and routes the data packet at the network layer of the protocol stack, processes the received data packet, and sends the processed data packet to the UAV through a radio frequency interface unit and a transceiver component; at the same time, a downlink data packet is sent to the protocol stack through the controller, transmitted to the network layer through the wireless physical layer and the wired network interface layer, received and routes the data packet at the network layer, processes the received data packet, and sends the processed data packet to the ground end through the network interface unit; thereby, transparent transmission of data packets between the ground end and the UAV is achieved, and user data can detect the destination address of the data packet at the network layer for reception or forwarding without transmitting it to the application layer for judgment, thereby reducing the time edge of data transmission and improving the transmission efficiency of the transparent transmission device.

[0014] The UAV data transparent transmission method based on the LWIP protocol stack of the present invention configures a wireless network interface at the network interface layer of the LWIP protocol stack, adds a wireless network interface layer protocol, and modifies the data forwarding strategy of the network layer, so that users can perform cross-segment network communication through simple routing configuration. Compared with ordinary UAV data transmission equipment, the versatility and user-friendliness of UAV communication equipment are improved, and data forwarding delay is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of a drone data transparent transmission device based on the LWIP protocol stack for this application; Figure 2 This is a schematic diagram of the structure of the protocol stack in a drone data transparent transmission method based on the LWIP protocol stack in this application; Figure 3 This is a data interaction diagram of a drone data transparent transmission method based on the LWIP protocol stack in this application; Figure 4 This application provides a processing flow chart of the network layer in a drone data transparent transmission method based on the LWIP protocol stack.

[0016] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0018] The first embodiment of the present invention provides a UAV data transparent transmission device based on the LWIP protocol stack, such as Figure 1 As shown, it includes a network interface unit, a controller, a radio frequency interface unit and a transceiver component; wherein the network interface unit is connected to the ground end and is used to receive uplink data packets from the ground end; the controller is connected to the network interface unit and is used to send the uplink data packets to the protocol stack for encapsulation processing, and process the encapsulated data packets (including encoding and modulation) into baseband signals; the radio frequency interface unit is connected to the controller and is used to convert (i.e., up-convert) the baseband signal into a radio frequency signal; the transceiver component is connected to the radio frequency interface unit and the antenna, and is used to pre-process (including filtering and amplifying) the radio frequency signal, and convert it into an uplink wireless signal and send it to the target UAV; it is also used to receive the downlink wireless signal of the target UAV and convert the downlink wireless signal into a radio frequency signal; the radio frequency interface unit is also used to convert (i.e., down-convert) the radio frequency signal into a baseband signal; the controller is also used to process (including demodulation and decoding) the baseband signal into a digital signal, and send it to the protocol stack for decapsulation processing to obtain a downlink data packet; the network interface unit is also used to send a downlink data packet to the ground end. It also includes a power supply unit, which is respectively connected to the network interface unit, the controller, the radio frequency interface unit and the transceiver component. The power supply unit provides a stable voltage for the controller, the network interface unit, the radio frequency interface unit and the TR transceiver component as needed.

[0019] Exemplarily, the network interface unit is a network interface chip, and its model may be RTL8211, 88E1518 or LAN8742. The radio frequency interface unit is a radio frequency interface chip, and its model may be AD9361, AD9371 or AD9026. The model of the controller may be ZYNQ7100, ZYZQ7045 or ZYNQ7020.

[0020] Furthermore, the transceiver component includes a power amplifier and a filter, the power amplifier is connected to the output end of the radio frequency interface unit, and the filter is connected to the input end of the radio frequency interface unit.

[0021] In this embodiment, a data packet from the ground end is received through the network interface unit, and the data packet is sent to the protocol stack through the controller, transmitted to the network layer through the wired physical layer and the wired network interface layer, received and routed at the network layer, processed, and sent to the drone through the RF interface unit and the transceiver component; at the same time, the data packet sent by the drone is received through the transceiver component, and sent to the protocol stack through the RF interface unit and the controller, transmitted to the network layer through the wireless physical layer and the wired network interface layer, received and routed at the network layer, processed, and sent to the ground end through the network interface unit; thereby, transparent transmission of data packets between the ground end and the drone is achieved, and user data can detect the destination address of the data packet at the network layer for reception or forwarding without being transmitted to the application layer for judgment, thereby reducing the time edge of data transmission and improving the transmission efficiency of the transparent transmission device.

[0022] The second embodiment of the present invention provides a method for transparent transmission of drone data based on the LWIP protocol stack, using the above-mentioned drone data transparent transmission device based on the LWIP protocol stack, comprising the following steps: The uplink data packet from the ground end is received through the network interface unit, and the controller sends the uplink data packet to the protocol stack for processing, and processes the encapsulated data packet (including encoding and modulation) into a baseband signal, and converts the baseband signal into an RF signal through the RF interface unit, and filters and amplifies the RF signal through the transceiver component, and converts it into an uplink wireless signal, and sends it to the target drone; the downlink wireless signal from the target drone is received through the transceiver component, and the downlink wireless signal is converted into an RF signal, and the RF signal is down-converted into a baseband signal through the RF interface unit, and the baseband signal is converted into a digital signal through the controller, and sent to the protocol stack for processing into a downlink data packet, and sent to the ground end. Among them, if Figure 2 As shown in the figure, the LWIP protocol stack includes a wired physical layer, a wireless physical layer, a network interface layer, a network layer, a transport layer, and an application layer; the processing of the protocol stack specifically includes the following steps: Step S1, configuring a wired physical layer for a network interface unit through a controller; Specifically, the network interface unit is connected to the PS processor system of the controller through the MDIO interface for interface configuration; the network interface unit is connected to the PL logic part of the controller through the RGMII interface for data communication. Interface configuration, that is, the physical layer configuration of the wired interface is as follows: the controller reads and writes the register of the network interface unit through the MDIO interface to obtain the register parameters of the network interface unit. The main register parameters of the network interface unit include the working mode and the interface mode.

[0023] Step S2, configuring a wireless physical layer for the radio frequency interface unit through the controller; Specifically, the RF interface unit is connected to the PS processor system of the controller through the SPI interface for interface configuration; the RF interface unit is connected to the PL logic part of the controller through the LVDS interface for data communication. Interface configuration, that is, the wireless physical layer configuration method is: the controller reads and writes the registers of the wireless physical layer and the RF interface unit through the SPI interface to obtain the register parameters of the RF interface unit. The register parameters of the RF interface unit include RF channel, sampling rate, bandwidth, frequency and working mode.

[0024] Step S3, configure the network interface layer. This mainly includes configuring the wired network interface layer and the wireless network interface layer, wherein the wired network interface layer has been implemented in the LWIP protocol stack, and the wireless network interface layer needs to modify the LWIP protocol stack to add the protocol layer, and the specific steps are as follows.

[0025] Step S31, configuring a driver function for setting a wireless network interface at the network interface layer; specifically, the driver function includes memory allocation, DMA interruption, and transceiver control; Step S32, initialize the protocol stack, that is, allocate the wireless network interface's own device information, and add the wireless network interface to the linked list of the network interface layer; wherein the information includes the IP address, the physical address, the subnet mask and the data receiving callback function, the subnet mask is used to divide the network part and the host part, the physical address is used for network routing forwarding, and the data receiving callback function is used to interrupt the processing of received data.

[0026] Step S33: setting the wireless network interface as the default destination network in the routing table.

[0027] Step S4, sending the data packet to the protocol stack through the wired physical layer or the wireless physical layer, receiving or forwarding the data packet through the network layer, and encapsulating or decapsulating the received data packet through the transport layer and the application layer; Specifically, the data packet includes an uplink network frame and a downlink wireless frame; wherein the uplink network frame is received through the network interface unit, and the downlink wireless frame is received through the TR component and the radio frequency interface unit. After receiving the uplink network frame and the downlink wireless frame, it is necessary to classify them to determine whether the data packet is an ARP request frame or an IP data frame. If it is an ARP request frame, it is necessary to compose an ARP reply frame for reply, and then perform subsequent data packet transparent transmission; if it is an IP data frame, it is directly transparently transmitted. The specific method is as follows.

[0028] like Figure 3-4As shown, when an uplink network frame is received, the uplink network frame is transmitted to the network layer through the wired physical layer and the wired network interface by the controller, and the data packet is classified at the network layer. When it is determined that the uplink network frame is of the ARP data type and the destination address of the current data frame is the IP address of its own device, the IP address and physical address of its own device are combined into a reply frame, and a unicast reply is performed according to the physical layer source of the data packet; when it is determined that the uplink network frame is of the ARP data type and the destination address of the current data frame is not the IP address of its own device, it is necessary to query the routing configuration. If the destination address exists in the destination network of the routing table, it is necessary to modify the source physical address and the destination physical address of the IP frame, and then recompose the uplink wireless frame and send it out through the forwarding port of the routing table.

[0029] When it is determined that the uplink network frame is an IP data frame, and the destination address of the current IP data frame is the IP address of its own device, the IP data frame is passed upward to the physical layer and application layer; when it is determined that the uplink network frame is an IP data frame, and the destination address of the current IP frame is not the IP address of its own device, the IP data frame is routed and forwarded. Specifically, if the destination address of the IP data frame is not the IP address of its own device, it is necessary to query the routing configuration. If the destination address exists in the destination network of the routing table, it is necessary to modify the source physical address and destination physical address of the IP data frame, and then reassemble the uplink wireless frame and send it out through the forwarding port of the routing table. When forwarding specifically: data entering the wired port is forwarded by the wireless port, or data entering the wireless port is forwarded through the wired port.

[0030] When receiving a downlink wireless frame, the controller transmits the downlink wireless frame to the network layer through the wireless physical layer and the wireless network interface, classifies the data packet at the network layer, and when it is determined that the downlink wireless frame is a request data packet and the destination address of the current request data packet is the IP address of the own device, the IP address and physical address of the own device are combined into a reply frame; the reply frame is replied to the target drone end through the wireless network interface in the form of an uplink wireless frame through the wireless physical layer; When it is determined that the downlink wireless frame is a request data packet and the destination address of the current request data packet is not the IP address of its own device, it is necessary to query the routing configuration. If the destination address exists in the destination network of the routing table, it is necessary to modify the source physical address and destination physical address of the IP frame, reassemble the downlink network frame and send it out through the forwarding port of the routing table.

[0031] When it is determined that the downlink wireless frame is an IP data frame and the destination address of the current IP data frame is the IP address of its own device, the IP data frame is passed upward to the physical layer and the application layer; when it is determined that the downlink wireless frame is an IP data frame and the destination address of the current IP frame is not the IP address of its own device, the IP data frame is routed and forwarded. Specifically, if the destination address of the IP data frame is not the IP address of its own device, it is necessary to query the routing configuration. If the destination address exists in the destination network of the routing table, it is necessary to modify the source physical address and the destination physical address of the IP data frame, reassemble the downlink network frame and send it out through the forwarding port of the routing table.

[0032] In this embodiment, by configuring a wireless network interface at the network interface layer of the LWIP protocol stack, adding a wireless network interface layer protocol, and modifying the data forwarding strategy of the network layer, users can conduct cross-segment network communication through simple routing configuration. Compared with ordinary drone data transmission equipment, the versatility and user-friendliness of drone communication equipment are improved, and the data forwarding delay is reduced.

[0033] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A drone data transparent transmission device based on LWIP protocol stack, characterized in that: include: A network interface unit, connected to the ground terminal, for receiving uplink data packets from the ground terminal; A controller, connected to the network interface unit, configured to send the uplink data packet to the protocol stack for encapsulation processing, and process the encapsulated data packet into a baseband signal; A radio frequency interface unit, connected to the controller, for converting the baseband signal into a radio frequency signal; A transceiver component is connected to the RF interface unit and the antenna, and is used to pre-process the RF signal and convert it into an uplink wireless signal to send to the target UAV; it is also used to receive the downlink wireless signal of the target UAV and convert the downlink wireless signal into a RF signal; The radio frequency interface unit is also used to convert the radio frequency signal into a baseband signal; The controller is also used to process the baseband signal into a digital signal and send it to the protocol stack for decapsulation processing to obtain a downlink data packet; The network interface unit is also used to send the downlink data packet to the ground terminal.

2. A method for transparent transmission of drone data based on LWIP protocol stack, characterized in that: Using the transparent transmission device according to claim 1, the method comprises: The network interface unit receives an uplink data packet from the ground end, the controller sends the uplink data packet to the protocol stack for processing, and the radio frequency interface unit and the transceiver component sequentially convert the processed data packet into an uplink wireless signal, which is sent to the target drone; The downlink wireless signal of the target UAV is received by the transceiver component, and the downlink wireless signal is converted into a digital signal through the radio frequency interface unit and the controller in sequence, and sent to the protocol stack for processing into a downlink data packet, and then sent to the ground end; The protocol stack includes a wired physical layer, a wireless physical layer, a network interface layer, a network layer, a transport layer and an application layer; the processing of the protocol stack includes: configuring a wired physical layer for a network interface unit by a controller; configuring a wireless physical layer for the radio frequency interface unit through the controller; Setting a wireless network interface driver function in the network interface layer; Allocate the wireless network interface with its own device information, add the wireless network interface to the network interface layer linked list, and set the wireless network interface as the default destination network in the routing table; The received data packets are transmitted to the protocol stack through the wired physical layer or the wireless physical layer, the data packets are transmitted to the network layer through the network interface layer, the data packets are received or forwarded through the network layer, and the received data packets are encapsulated or decapsulated through the transport layer and the application layer.

3. The method for transparent transmission of drone data based on the LWIP protocol stack according to claim 2 is characterized in that: The information includes IP address, physical address, and data receiving callback function; The network layer receives or forwards the data packet, including: Classify the data packet, and when it is determined that the data packet is of ARP data type and the destination address of the current data frame is the IP address of the own device, compose a reply frame with the IP address and physical address of the own device, and perform a unicast reply according to the physical layer source of the data packet; When it is determined that the data packet is an ARP request data packet and the destination address of the current request data packet is not the IP address of its own device, the routing table is searched for the destination address of the request data packet and then routing forwarding is performed.

4. The method for transparent transmission of drone data based on the LWIP protocol stack according to claim 3 is characterized in that: The receiving or forwarding of the data packet at the network layer also includes: When it is determined that the data packet is an IP data packet and the destination address of the current IP frame is the IP address of the own device, it is passed upward to the transport layer and the application layer; When it is determined that the destination address of the data packet is not the IP address of its own device, the data packet is routed and forwarded.

5. The method for transparent transmission of drone data based on LWIP protocol stack according to claim 2 is characterized in that: The method of configuring a wired physical layer for a network interface unit through a controller includes: The controller performs read and write operations on the register of the network interface unit through the MDIO interface to obtain the register parameters of the network interface unit.

6. The method for transparent transmission of drone data based on the LWIP protocol stack according to claim 5 is characterized in that: The register parameters of the network interface unit include configurations of the working mode and the interface mode.

7. The method for transparent transmission of drone data based on LWIP protocol stack according to claim 2 is characterized in that: The step of configuring the wireless physical layer for the radio frequency interface unit by using the controller includes: The controller reads and writes the registers of the wireless physical layer and the radio frequency interface unit through the SPI interface to obtain the register parameters of the radio frequency interface unit.

8. The method for transparent transmission of drone data based on the LWIP protocol stack according to claim 7 is characterized in that: The register parameters of the RF interface unit include RF channel, sampling rate, bandwidth, frequency and working mode.

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