In recent years, as the competition for employment has become more and more intense, research on the quality of employment of graduates has become increasingly extensive and in-depth. Below are the computer papers I recommend for everyone for your reference.
Computer paper sample 1: Analysis of cognitive radio system composition and application scenarios
Cognitive radio system composition
Cognitive radio system refers to the use of cognitive radio It is a wireless communication system with advanced technology that makes communication systems more flexible with the help of more flexible transceiver platforms and enhanced computing intelligence. The cognitive radio system mainly includes three functional modules: information acquisition, learning, and decision-making and adjustment, as shown in Figure 1 [3].
The primary feature of a cognitive radio system is the ability to acquire knowledge of the radio external environment, internal status and related policies, as well as the ability to monitor user needs. The cognitive radio system has the ability to obtain the external radio environment and analyze and process it. For example, by analyzing the current spectrum usage, the carrier frequency and communication bandwidth of the wireless communication system can be expressed, and its coverage and interference level can even be obtained. Information; the cognitive radio system has the ability to obtain radio internal status information, which can be obtained through its configuration information, traffic load distribution information, transmit power, etc.; the cognitive radio system has the ability to obtain relevant policy information, and radio policy information stipulates The frequency band that the cognitive radio system can use in a specific environment, the maximum transmit power, and the frequency and bandwidth of adjacent nodes, etc.; the cognitive radio system has the ability to monitor user needs and make decisions and adjustments based on user needs. As shown in Table 1, users' business requirements can generally be divided into three categories: voice, real-time data (such as images) and non-real-time data (such as large file packages). Different types of services have different requirements for communication QoS.
The second main feature of cognitive radio systems is the ability to learn. The goal of the learning process is to improve performance using information from previously stored decisions and outcomes of the cognitive radio system. According to different learning content, learning methods can be divided into 3 categories. The first type is supervised learning, which is used to learn the external environment, mainly using measured information to train the estimator; the second type is unsupervised learning, which is used to learn the external environment, mainly extracting parameters related to the external environment. The changing rules; the third category is reinforcement learning, which is used to learn internal rules or behaviors, mainly through reward and punishment mechanisms to highlight the rules or behaviors that adapt to the current environment, and abandon the rules or behaviors that are not suitable for the current environment. Machine learning technology can be divided into mechanical learning, explanation-based learning, guided learning, analogical learning and inductive learning according to the learning mechanism.
The third main characteristic of a cognitive radio system is the ability to dynamically and autonomously adjust its operating parameters and protocols based on acquired knowledge, with the purpose of achieving some predetermined goals, such as avoiding interference with other systems. Adverse interference with radio systems. The adjustability of cognitive radio systems does not require user intervention. It can adjust working parameters in real time to achieve appropriate communication quality; or to change the wireless access technology in a certain connection; or to adjust the radio resources in the system; or to adjust the transmit power to reduce interference. Cognitive radio systems analyze acquired knowledge, make decisions and reconstruct dynamically and autonomously. After reconfiguration decisions are made, in response to control commands, the cognitive radio system can change its operating parameters and/or protocols based on these decisions. The decision-making process for cognitive radio systems may include understanding the needs of multiple users and the wireless operating environment, and establishing a policy aimed at selecting appropriate configurations to support the unique needs of these users.
The relationship between cognitive radio and other radios
Before cognitive radio was proposed, there were already some concepts of "such and such radio", such as software-defined radio, adaptive radio, etc. Their relationship with cognitive radio is shown in Figure 2. Software-defined radio is considered an enabling technology for cognitive radio systems. Software-defined radio does not require the characteristics of CRS to work. SDR and CRS are in different stages of development, that is, radio communication systems using SDR applications have been utilized, while CRS is in the research stage, and its applications are also being studied and tested.
SDR and CRS are not radio communication services, but technologies that can be used comprehensively in any radio communication service. Adaptive radios adjust parameters and protocols to adapt to preset channels and environments. Compared with cognitive radio, adaptive radio does not have the learning ability. It cannot learn from the acquired knowledge and decisions made, nor can it improve the way of acquiring knowledge and adjust the corresponding decisions through learning. Therefore, it cannot adapt to Unpreset channels and environments. A reconfigurable radio is a radio whose hardware functionality can be changed through software control, with the ability to update some or all of the physical layer waveforms, as well as higher layers of the protocol stack. Policy-based radios can be updated to adapt to local regulatory policies without changing internal software. As with newer radio networks, Internet routers have always been policy-based. This allows network operators to use policies to control access, allocate resources, and modify network topology and behavior. For cognitive radio, policy-based technology should enable products to be used around the world, automatically adapt to local regulatory requirements, and be automatically updated as regulatory rules change over time and experience. A smart radio is a radio that predicts the future based on previous and current conditions and adjusts in advance. Compared with smart radios, where adaptive radios only determine strategies and make adjustments based on the current situation, cognitive radios can learn, determine strategies, and make adjustments based on previous results.
Key technologies of cognitive radio
The key technologies of cognitive radio systems include wireless spectrum sensing technology, intelligent resource management technology, adaptive transmission technology and cross-layer design technology. They are Cognitive radio distinguishes the characteristic technologies of traditional radio [4, 5].
According to the detection strategy, spectrum detection can be divided into physical layer detection, MAC layer detection and multi-user collaborative detection, as shown in Figure 3. 3.1.1 Physical layer detection The detection method of the physical layer is mainly to determine whether the frequency band is occupied by detecting whether there is an authorized user signal in the time domain, frequency domain and air domain. The detection of the physical layer can be divided into the following three methods :The main methods of transmitter detection include energy detection, matched filter detection, cyclostationary characteristic detection, etc., as well as multi-antenna detection based on one of these methods. When the authorized user receiver receives a signal, a local oscillator needs to be used to convert the signal from high frequency to intermediate frequency. During this conversion process, some energy of the local oscillator signal will inevitably leak out through the antenna, so it can be achieved by converting the low frequency to the intermediate frequency. The power consumption detection sensor is placed near the authorized user receiver to detect the energy leakage of the local oscillator signal, thereby determining whether the authorized user receiver is working. The interference temperature model allows people to shift the way of evaluating interference from the operation of a large number of transmitters to the real-time interaction between transmitters and receivers in an adaptive manner. The basis is the interference temperature mechanism, that is, through the authorized user receiver side Interference temperature to quantify and manage interference sources in wireless communication environments. MAC layer detection mainly focuses on how to improve throughput or spectrum utilization under multi-channel conditions. In addition, it also optimizes the channel detection sequence and detection period to maximize the number of available idle channels detected or minimize the average channel search time. . MAC layer detection can be mainly divided into the following two methods: Active detection is a periodic detection, that is, when the cognitive user has no communication needs, the relevant channels will be detected periodically. The information obtained by using periodic detection can be estimated Statistical properties of channel usage. Passive detection is also called on-demand detection. Cognitive users only detect all authorized channels in sequence when they have communication needs until an available idle channel is found. Due to unfavorable factors such as multipath fading and occlusion shadows, it is difficult for a single cognitive user to make a correct decision on whether there is an authorized user signal. Therefore, multiple cognitive users need to cooperate with each other to improve the sensitivity and accuracy of spectrum detection, and Reduce detection time. Collaborative detection combines the detection technology of physical layer and MAC layer functions. It not only requires each cognitive user to have high-performance physical layer detection technology, but also requires the MAC layer to have efficient scheduling and coordination mechanisms.
The goal of intelligent resource management is to maximize spectrum efficiency and system capacity within limited bandwidth while meeting user QoS requirements, while effectively avoiding network congestion.
In cognitive radio systems, the total capacity of the network has certain time variability, so a certain access control algorithm needs to be adopted to ensure that newly accessed connections will not affect the QoS requirements of existing connections in the network. Dynamic spectrum access conceptual models can generally be divided into three categories as shown in Figure 4. The dynamic exclusive model retains the basic structure of the current static spectrum management policy, that is, spectrum is licensed to specific communication services for exclusive use. The main idea of ??this model is to introduce opportunities to improve spectrum utilization, and includes two implementation methods: spectrum property rights and dynamic spectrum allocation. The open sharing model, also known as the spectrum public model, opens the spectrum to all users for their sharing, such as the open sharing method of the ISM frequency band. The core idea of ??the hierarchical access model is to open licensed spectrum to unlicensed users, but restrict the operations of unlicensed users to a certain extent to avoid interference to authorized users. There are two types of spectrum underlaying and spectrum filling. Spectrum allocation in cognitive radio is mainly based on two access strategies: ① Orthogonal spectrum access. In orthogonal spectrum access, only one cognitive user is allowed to access each channel or carrier at a time. After the allocation is completed, the communication channels between cognitive users are orthogonal to each other, that is, there is no interference between users. (or the interference is negligible). ②*** Enjoy spectrum access. In shared spectrum access, cognitive users access multiple channels or carriers of authorized users at the same time. In addition to the interference tolerance of authorized users, users also need to consider interference from other users. According to the interference tolerance constraints of authorized users, the above two access strategies can be divided into the following two spectrum access modes: filling spectrum access and underlay spectrum access. For fill-in spectrum access, cognitive users wait for opportunistic access to "spectrum holes". They only need to transfer the spectrum in a timely manner when authorized users appear without additional interference problems when sharing channels with authorized users. This kind of The method is easy to implement and does not require existing communication equipment to provide interference tolerance parameters. In the underlying spectrum access mode, cognitive users and authorized users share the spectrum and need to consider the additional interference restrictions when using the channel.
Without affecting the communication quality, power control can be used to minimize the power of the transmitted signal, which can improve the channel capacity and increase the standby time of the user terminal. The power control algorithm design in cognitive radio networks faces a multi-objective joint optimization problem. Due to different requirements of different objectives, there are many compromise solutions. According to different application scenarios, the existing power control algorithms in cognitive radio networks can be divided into two major categories: one is the power control strategy suitable for distributed scenarios, and the other is the power control strategy suitable for centralized scenarios. Most of the power control strategies in distributed scenarios are based on game theory. Some also refer to the power control methods in traditional Adhoc networks, starting from centralized strategies and then converting centralized strategies into distributed strategies; while the power in centralized scenarios Most control strategies take advantage of the base station's ability to centrally process information and adopt a joint strategy, that is, combining power control with spectrum allocation or jointly considering power control and access control.
Adaptive transmission can be divided into service-based adaptive transmission and channel quality-based adaptive transmission. Service-based adaptive transmission is to meet the different QoS requirements of multi-service transmission. It is mainly implemented in the upper layer without considering the actual transmission performance of the physical layer. This adaptive transmission technology is currently considered in wired networks. Cognitive radio can use related technologies to optimize radio parameters and adjust related transmission strategies based on perceived environmental parameters and channel estimation results. Optimization here means that the wireless communication system minimizes the resources it consumes while meeting the user's performance level, such as minimizing occupied bandwidth and power consumption. Parameters that may be adjusted by the physical layer and media control layer include center frequency, modulation method, symbol rate, transmit power, channel coding method, access control method, etc. Obviously, this is a nonlinear multi-parameter multi-objective optimization process.
Existing layered protocol stacks only consider the worst communication conditions when designing, resulting in the inability to effectively utilize limited spectrum resources and power resources. Cross-layer design coordinates the operation of each layer by introducing and transmitting specific information between each layer of the existing layered protocol stack to adapt to the complex and changing wireless communication network environment, thereby satisfying users' needs for various new technologies. different needs of business applications.
The core of cross-layer design is to enable each layer of the layered protocol stack to adaptively optimize and configure various network resources according to changes in the network environment and user needs. In cognitive radio systems, there are mainly the following cross-layer design technologies: In order to select appropriate spectrum holes, dynamic spectrum management strategies need to consider high-level QoS requirements, routing, planning and sensing information. The mutual influence and close integration of the physical layer make the dynamic spectrum management solution must be designed across layers. The spectrum mobility function needs to be combined with other spectrum management functions such as spectrum sensing to jointly determine an available frequency band. In order to estimate the impact of spectrum handover duration on network performance, link layer information and perceived delays are required. The network layer and application layer should also know this duration to reduce sudden performance degradation; in addition, routing information is also important for the route discovery process using spectrum switching. The performance of spectrum sharing directly depends on the spectrum sensing capability in the cognitive radio network. Spectrum sensing is mainly a function of the physical layer. However, in the case of cooperative spectrum sensing, cognitive radio users need to exchange detection information, so cross-layer design between spectrum sensing and spectrum sharing is necessary. In a cognitive radio system, since the available spectrum for each hop in multi-hop communication may be different, the network topology configuration needs to know the information of spectrum sensing. Moreover, a main idea of ??routing design of cognitive radio system is routing and spectrum. combined with decision-making.
Cognitive radio application scenarios
Cognitive radio systems can not only use spectrum effectively, but also have many potential capabilities, such as improving system flexibility, enhancing fault tolerance and improving energy efficiency. wait. Based on the above advantages, cognitive radio has broad application prospects in civilian and military fields.
Spectral efficiency can be improved not only by improving the spectrum efficiency of a single wireless access device, but also by improving the storage performance of each wireless access technology. This new way of utilizing spectrum is expected to increase the performance of the system and the economic value of the spectrum. Therefore, these improvements in the save/share performance of cognitive radio systems promote the development of a new way of spectrum utilization and enable new access to spectrum in a save/share manner. spectrum is possible. The capabilities of cognitive radio systems also help to improve system flexibility, mainly including improving the flexibility of spectrum management, improving the flexibility of equipment operation during the life cycle, and improving system robustness. Fault tolerance is a major performance of communication systems, and cognitive radio can effectively improve the fault tolerance of communication systems. Usually fault tolerance is mainly based on in-machine testing, fault isolation and error correction measures. Another advantage of cognitive radio for fault tolerance is the ability of cognitive radio systems to learn fault, response, and error messages. Cognitive radio systems can improve power efficiency by adjusting operating parameters, such as bandwidth or signal processing algorithms based on business needs.
What cognitive radio wants to solve is the problem of resource utilization. The advantages of application in rural areas can be summarized as follows. The main frequency bands used in rural radio spectrum are broadcasting, television bands and mobile communication bands. Its characteristics are that the occupation of broadcast frequency bands is basically the same as that in cities, the utilization of TV frequency bands is less than that in cities, and the occupation of mobile communication frequency bands is less than that in cities. Therefore, considering the frequency domain, the available frequency resources are richer than those in cities. Rural economies are generally less developed than cities. Except for the relatively fixed occupation of TV bands, the utilization rate of mobile communications is not as high as that of cities. Therefore, the utilization rate of allocated frequencies is relatively low. Because rural areas are vast and sparsely populated, mobile cells are limited by the radiation radius, leaving a large number of areas without mobile communication frequency coverage, especially in remote areas, where the available resources in frequency space are quite abundant.
In a heterogeneous wireless environment, one or more operators run multiple wireless access networks on different frequency bands allocated to them. Using cognitive radio technology allows terminals to choose different operators. and/or capabilities of different radio access networks, some of which may also have the ability to support multiple simultaneous connections on different radio access networks. Since the terminal can use multiple wireless networks at the same time, the communication bandwidth of the application increases. As the terminal moves and/or the wireless environment changes, appropriate wireless networks can be quickly switched to ensure stability.
In the field of military communications, possible application scenarios of cognitive radio include the following three aspects.
Cognitive interference-resistant communication. Because cognitive radio gives the radio the ability to perceive the surrounding environment, it can extract the characteristics of interference signals, and then select appropriate anti-interference communication strategies based on the electromagnetic environment perception information, interference signal characteristics, and communication service needs, greatly improving the radio's performance. Anti-interference level. Battlefield electromagnetic environment perception. One of the characteristics of cognitive radio is the integration of inductive environmental sensing and communication. Since each radio station is both a communication radio and an electromagnetic environment sensing radio, the radios can be used to form an electromagnetic environment sensing network to effectively meet the full-time, full-band and full-region requirements for electromagnetic environment sensing. Battlefield electromagnetic spectrum management. The electromagnetic spectrum in modern battlefields is no longer the traditional radio communication spectrum, and static and centralized spectrum management strategies can no longer meet the requirements of flexible and changeable modern warfare. Battlefield electromagnetic spectrum management based on cognitive radio technology gives spectrum sensing capabilities to various combat elements, allowing spectrum monitoring and spectrum management to proceed simultaneously, greatly improving the coverage of the spectrum monitoring network and broadening the frequency bands covered by spectrum management.
Conclusion
How to improve spectrum utilization to meet users’ bandwidth needs; how to make radio intelligent so that it can autonomously discover when, where and how to use wireless resource acquisition Information services; how to effectively obtain information from the environment, learn, make effective decisions and make adjustments, all of which are problems to be solved by cognitive radio technology. The introduction of cognitive radio technology provides strong support for realizing wireless environment perception, dynamic resource management, improving spectrum utilization and achieving reliable communication. Cognitive radio has broad application prospects and is another milestone in the development of radio technology.
Computer paper sample two: Design research of remote wireless control system
1 Introduction
With the development of my country's aerospace industry, the tasks undertaken by survey ships have emerged The trend of high density and high intensity has caused the task preparation work during the terminal to become more and more arduous. Faced with the reality of multiple assessment projects, short assessment time and coordinated benchmarking of multiple ships, how to improve the efficiency of benchmarking and ensure safe and reliable benchmarking? become an urgent issue. Due to confidentiality requirements, the originally developed remote calibration control system cannot be connected to the existing network, and laying a private network is expensive and cost-effective, so it is not the first choice. In recent years, wireless communication has become the fastest-growing and most widely used technology in the field of information and communication. It is widely used in home, agriculture, industry, aerospace and other fields, and has become an indispensable part of social life in the information age [1], This technology also provides support for remote control of calibration equipment on survey ships. This paper compares commonly used medium and long-distance wireless communication methods, selects wireless bridges, adopts the bridge relay network mode, and realizes the measurement of ship-to-remote equipment by developing a network control module on the remote equipment side and corresponding control software. effective and safe control.
2 Comparison of wireless communication methods
Wireless communication technology is a communication method that uses electromagnetic wave signals to propagate information in free space. It can be divided into two categories according to the technical form: First, Cellular-based access technologies, such as cellular digital packet data, general packet wireless transmission technology, EDGE, etc.; second, local area network-based technologies, such as WLAN, Bluetooth, IrDA, Home-RF, micro-power short-range wireless communication technology, etc. Commonly used in medium and long-distance wireless communications are ISM band communication technologies (such as ZigBee and data transmission modules in other frequency bands, etc.) and wireless network technologies (such as GSM, GPRS, and wireless bridges, etc.). The communication frequency of the data transmission module based on the ISM frequency band is the public frequency band, and there are no restrictions on product development. Therefore, it has developed very rapidly and has been widely used. Especially the emerging ZigBee technology in recent years, because of its low power consumption, low complexity, low cost, especially the self-organizing method of networking, there is no limit on the number of devices in the network segment, and it can flexibly complete network links. In the intelligent It has been applied in the development of network systems such as home and wireless meter reading [2]. However, for the development of this system, the hardware modules of the control point and the controlled point need to be developed separately, and the network environment needs to be configured through software. The development cycle is long and the development cost is high, so it is not the optimal solution for the development of this system.
Wireless mobile communication technologies such as GSM and GPRS have become an indispensable part of people's daily life, and their applications in other fields such as wireless positioning and remote control are also common [3]. However, due to confidentiality, Factors such as communication costs and development costs cannot be applied to the development of this system. The wireless bridge provides favorable support for the low-cost, high-efficiency research and development of this system, and is the preferred wireless communication method for the development of this system. A wireless bridge is a bridge of wireless networks. It can build a communication bridge between two or more networks and is also a branch of a wireless access point. Wireless bridges work in the 2.4GHz or 5.8GHz wireless license-free frequency bands, so they are more convenient to deploy than other wired network equipment, and are especially suitable for short-distance and long-distance communications in cities.
3 System Design
The remote control system is aimed at ensuring the effective control of the remote calibration equipment by the measuring ship, including the switching on and off of the calibration equipment and the collection of status parameters. etc., mainly composed of measuring ship control microcomputer, calibration equipment, network control module, main control microcomputer and wireless network bridge. The workflow is as follows: the measurement ship control microcomputer or main control microcomputer sends control instructions, disseminates information through the wireless bridge, and the network control module receives and parses the instructions, and sends them to a certain calibration equipment through the serial port according to the data format specified by the Modbus protocol. The school equipment responds to the control instructions and executes them; the network control module regularly sends query instructions, packages the collected status data, and sends them to the remote control computer via wireless to facilitate operator monitoring. The network communication protocol adopts UDP mode. For the measurement ship control microcomputer and main control microcomputer, it only needs to send or receive UDP packets according to a certain data format. The network control module is the core component of the system and is the focus of the research and design of this article. At present, commonly used network chips mainly include ENC28J60, CP2200, etc. ENC28J60 was selected here to design and process a hardware circuit based on STC89C52RC microcontroller. Through the development of the network information processing software module, the functional requirements for network information interaction are met; through the development of the Modbus serial port protocol software module, the calibration equipment monitoring function is met, thereby achieving the system design goals.
3.1 Networking mode
Wireless bridge has three working modes, namely point-to-point, point-to-multipoint, and relay connection. According to the system control requirements and environmental factors, this system adopts the relay connection method, and its network topology is shown in Figure 1. It can be clearly seen from the figure that this relay connection method arranges two wireless bridges at the remote control end to communicate with the main control point and the client respectively, and completes data interaction through the network control module to complete the networking.
3.2 Security precautions
Due to its open design, wireless network security is an issue that must be considered. The characteristics of this system are non-scheduled or all-weather startup, the confidential data is only frequency parameters, and the controlled equipment itself has protection measures (protocol protection). Therefore, the system focuses on access point prevention and attack prevention when designing the system. Measures taken include login password facilities, network key settings, fixed IPs, dynamic encryption of confidential data in data structures, etc., so as to maximize the Prevented "being hacked". At the same time, network lightning protectors are used to protect against lightning damage.
3.3 Network control module design
3.3.1 Hardware design
The function of the network control module is to receive command information, send status information, and communicate with the standard through the serial port The school equipment realizes information interaction. Its hardware circuit is mainly composed of MCU (micro control unit), ENC28J60 (network chip), Max232 (serial port chip) and peripheral circuits. Its electrical schematic diagram is shown in Figure 2. The core of hardware design is the selection of MCU and network chips. The STC89C52RC microcontroller selected for the MCU of this system is a low-power, high-performance CMOS 8-bit microcontroller. It can be downloaded directly using the serial port and provides many embedded control application systems. Highly flexible and ultra-effective solution. ENC28J60 is a highly integrated Ethernet control chip produced by M-icrochip. Its interface complies with the IEEE802.3 protocol. Only 28 pins can provide corresponding functions, which greatly simplifies the related design.
ENC28J60 provides an SPI interface, and communication with the MCU is achieved through two interrupt pins and SPI, with a data transmission rate of 10Mbit/s. ENC28J60 complies with all IEEE802.3 specifications and uses a series of packet filtering mechanisms to limit incoming data packets. It provides an internal DMA module to achieve fast data throughput and hardware-supported IP checksum calculation[4] . ENC28J60's external network interface uses HR911102A, which has built-in network transformers, resistor networks, and status display lights. It has the characteristics of signal isolation, impedance matching, interference suppression, etc., which can improve the system's anti-interference ability and the stability of sending and receiving.
3.3.2 Software design
The software design of the network control module mainly includes two parts. One is the writing of the ENC28J60 driver based on the SPI bus, including the definition of the Ethernet data frame structure, Initialization and data sending and receiving; the second is Modbus protocol preparation, the software process is shown in Figure 3.
3.3.2.1 Driver preparation for ENC28J60
(1) The Ethernet data frame structure conforms to the IEEE802.3 standard. The length of the Ethernet frame is between 64~1516bytes. Mainly composed of destination MAC address, source MAC address, type/length field, data payload, optional padding field and cyclic redundancy check. In addition, when sending a data packet over the Ethernet medium, a 7-byte preamble field and a 1-byte start of frame delimiter are appended to the beginning of the Ethernet data packet. The structure of the Ethernet data packet is shown in Figure 4. (2) Driver writing 1) ENC28J60 register reading and writing rules Since the ENC28J60 chip uses the SPI serial interface mode, its rules for reading and writing internal registers are to send the opcode first
3.3.2.2 ModBus protocol process
The data communication of ModBus protocol in this system adopts RTU mode [5]. The network control module serves as the master node and the slave node (calibration equipment) through the serial port Establish a connection, the master node regularly sends query commands to the slave node, and the corresponding slave node responds to the command and sends device status information to the master node. When network data is detected, the command is parsed from the ENC28J60 received data packet, the corresponding function code and data are framed according to the Modbus data frame structure, and sent to the slave node; the corresponding slave node responds to the control command and performs device parameters set up.
4 System debugging and verification
The test debugging environment is arranged according to Figure 1, mainly including 5 wireless bridges, 1 main control point, 2 clients, and 1 network Control module boards and calibration equipment are mainly tested for network communication effects, network control capabilities and simple security protection tests.
Test conclusion: The network connection is reliable, each control point can safely control remote devices, has certain security protection capabilities, and fully meets the remote device control requirements.
5 Conclusion
Based on actual needs, this article selects wireless bridges to realize remote control system networking through comparison of popular wireless communication technologies; through the development of network control modules, As well as the corresponding control software compilation, a system for remote control equipment of measuring ships was developed. The application of several survey ships shows that the use of wireless bridges for networking fully meets the system design requirements, has the advantages of high security, high reliability, and high scalability, and plays an important role in increasingly heavy support tasks. The wireless networking method and hardware circuit design adopted in this system have certain reference value for other related control fields.