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What is a WiFi serial server? How does it work in wireless communication?
With the continuous development of wireless communication technology, as an important communication device, WiFi serial server is playing an increasingly critical role in various fields. This article will give an in-depth introduction to the concept of a WiFi serial server and its role in wireless communication.
What is a WiFi serial server?
WIFI serial server also known as wireless serial server or WiFi to Serial converter, is a device used to connect and convert traditional serial communication interfaces (such as RS-232, RS-485) to WiFi networks. It allows users to remotely access, control and monitor serial devices through a WiFi network, realizing wireless serial communication. This kind of equipment usually has a serial port interface, a WiFi module and a processor, which can convert the serial port data into network data and transmit it through the WiFi network.
The role of WiFi serial server
Remote access and control: WIFI serial server can turn traditional serial devices into devices that can be remotely accessed and controlled through WiFi networks. Users can achieve remote access and control through terminal devices (such as computers, mobile phones, and tablets) connected to the same WiFi network without physical contact with the device.
Wireless serial devices: Many traditional serial devices (such as industrial control equipment, monitoring instruments, etc.) usually lack wireless communication capabilities. By connecting to a WiFi serial server, these devices can realize wireless communication, which facilitates remote data transmission and monitoring.
Device networking: Single serial port server can bring serial devices into LAN or Internet to realize the interconnection between devices. This facilitates data sharing, monitoring and control, and also supports IoT applications.
Extended transmission distance: Traditional serial communication is limited by distance, but through the WiFi serial server, the serial communication can be extended to the coverage of the WiFi network, increasing the flexibility and reliability of communication.
Equipment integration and automation: The WiFi serial server can be integrated into the existing automation system to realize remote control and data collection of equipment. This helps to improve production efficiency and reduce labor costs.
Role in wireless communications
WiFi serial server plays an important role in wireless communication:
Real-time data transmission: Through the WiFi serial port server, the device can transmit data to a remote server or cloud platform in real-time to realize timely monitoring and analysis of data.
Remote maintenance: Maintenance personnel can connect to the equipment through the WiFi network for remote diagnosis and maintenance without on-site operation.
Flexible layout: By making serial devices wireless, devices can be arranged more flexibly, no longer limited by physical connection lines.
Internet of Things application: WiFi serial port server provides communication support for Internet of Things applications, enabling various devices to interconnect and realize intelligence and automation.
in conclusion
The WiFi serial server is a device that plays a key role in the field of wireless communication. It realizes wireless serial communication by connecting traditional serial devices with a WiFi network and provides users with the convenience of remote access, control, and monitoring. No matter in the fields of industrial automation, the Internet of Things, or smart home, WiFi serial servers are promoting the development of wireless communication technology, bringing more convenience and intelligence to people's life and work.
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How does the Remote I/O module realize remote data acquisition and control?
With the continuous development of industrial automation, Internet of Things and remote monitoring, Remote I/O (Input/Output) modules have become an important tool for remote data acquisition and control. These modules allow users to obtain environmental data and control remote equipment at remote locations, bringing convenience and intelligence to various industries. This article will discuss in depth how the Remote I/O module realizes the process of remote data acquisition and control.
1. Sensor interface and data acquisition
Remote I/O modules are usually equipped with a variety of sensor interfaces, including analog and digital inputs. The analog input is used to connect various analog sensors, such as temperature, humidity, pressure sensors, etc. The digital input is used to connect digital sensors, such as buttons, switches, photoelectric sensors, etc. These sensors convert the sensed physical quantities into electrical signals, and the Remote I/O module is responsible for reading and converting them into digital data for collection.
2. Communication interface and data transmission
Remote I/O modules are usually equipped with various communication interfaces, such as Ethernet, Wi-Fi, Bluetooth, RS-485, etc., for communicating with remote hosts or monitoring systems. Through these interfaces, the module can transmit the collected data to a remote server or cloud platform. These communication interfaces provide the key foundation for real-time data transmission and monitoring.
3. Data transfer protocol
The Remote I/O module transmits the collected data to the remote system using a specific communication protocol. Commonly used protocols include Modbus TCP, MQTT (Message Queuing Telemetry Transport), CoAP (Constrained Application Protocol), etc. These protocols ensure the secure transmission and interpretation of data, enabling remote systems to accurately understand and process the data.
Related terms:
Ethernet IO
RS485/RS232 IO
4. Remote monitoring and control
After being transmitted to a remote server or cloud platform, the data can be monitored and analyzed in real time. Users can access these data through remote terminal devices (such as computers, mobile phones, and tablets) to understand the status of the environment in real time. At the same time, users can also make corresponding control decisions based on monitoring data. Send control commands to the Remote I/O module through the cloud platform to realize remote device control, such as switch control, parameter adjustment, etc.
5. Feedback and alarm
The Remote I/O module can not only feed back the results of control operations to the cloud platform or remote Serial server but also monitor environmental parameters and trigger an alarm mechanism. If an abnormal situation is detected or exceeds a preset threshold, the module can immediately trigger an alarm and send a notification to the user to help the user take timely measures.
To sum up, the Remote I/O module realizes the function of remote data acquisition and control through key links such as sensor interface, data acquisition, communication transmission and remote control. These modules play an indispensable role in industrial automation, Internet of Things, remote monitoring and other fields, bringing convenience, efficiency and intelligence to various industries. Through continuous technological innovation and application expansion, the Remote I/O module will further promote the development of remote data acquisition and control technology, and create more possibilities for the future intelligent world.
What is LORA?
What is LORA?
Whenever someone asks me "what is LORA", if I don't know why he asked me this question, it is difficult for me to know how to answer his question, because LORA does not only refer to a thing, So I will let the editor of Chengdu Yibyte Electronic Technology Co., Ltd. answer this question for everyone. Technically speaking, LORA is a radio modulation scheme - a multi-symbol modulation radio signal using Chirp method; LORA technology also refers to systems that support modulation, including LORA chips and gateways; sometimes it refers to LORA communication networks in IoT applications. In essence, LORA chips are very cheap, but they have high acceptance sensitivity And low bit error rate (BER).
This means that in low-speed application scenarios, using LORA can get LoRaWAN farther than using other radio technologies of the same price. LoRaWAN is a media access control ( MAC) layer protocol, built using Semtech's LoRa modulation scheme (LoRa is just a physical layer protocol). However, LoRaWAN is rarely used in industrial (private network) application scenarios, it is more suitable for LoRa Wireless module public wide area networks because all channels are modulated to the same frequency ;For a private network, in order to avoid conflicts, it is best to have only one network running. The above picture is a network architecture diagram of LoRaWAN, all gateways in the network are bound to the same server, and the server decides which gateway should respond to the transmission. In a large In the network, any given transmission is usually detected by multiple receivers; then the server notifies a gateway to respond, and other gateways ignore the transmission.
This process helps to avoid conflicts between uplink and downlink, because only one gateway is transmitting, and overlapping A gateway can simply listen for other transmissions. What many people don't realize is that there is a way to use LoRaWAN's underlying technology (aka LoRa) without using LoRaWAN. LoRa module For example, Link Labs' Symphony Link in Semtech's A proprietary MAC layer is used on the chip, making it more suitable for enterprise and industrial customers who need to securely connect IoT devices to the cloud. In addition, there are many companies using LoRa chips in other protocols. From Answer "What is LoRa" at the technical level From a technical point of view, bluetooth Wireless Module is a unique modulation method. Semtech RF components (SX1272, SX1276/7/8 transceiver chips) integrate LoRa modulation technology (this technology is a proprietary modulation technology, currently Technical details have not been disclosed), the technology is called frequency modulation (FM) Chirp.
The core technology of LoRa is to use fractional phase-locked loop (PLL) to generate a stable Chirp signal. Other modulation formats include frequency shift keying (FSK), phase shift Keying (PSK), etc. It is important to note that LoRa itself does not describe system functionality above the physical (RF medium) layer. Let's first look at the Chirp signal (this word comes from the signal characteristics of the bird's call of the same name, and it can also be called frequency sweep for signal processing). The characteristic of Chirp is that the frequency of the signal changes with a certain rule, while the signal of FSK will only switch between two frequency points. The following figure is a linear Chirp signal time domain diagram. LoRa Internet of Things Protocol Semtech acquired the French Cycleo SAS for $5 million in 2012, thus obtaining LoRa wireless technology. The modem can filter the Chirp signal when processing the LoRa message, so it can obtain additional processing gain and improve the receiving sensitivity. In order to "lock" the LoRa signal, a long "constant Chirp" preamble needs to be transmitted (see Figure 1). This is the uniqueness of Lora - very high receiving sensitivity can be obtained using cheap chips and crystals.
This leading signal can be set to a variable number of "symbols", that is, the number of Chirps. It is conceivable that there is no selectivity between the preamble signals of different LoRa transmitters, but the LoRa demodulator can listen to a constant Chirp signal at the appropriate frequency and Chirp change rate (regardless of whether it comes from the intended system or not). The anti-interference performance of a LoRa receiving system in the face of conventional power interference and LoRa interference is very important, which is also the key technology of Symphony Link. Once the LoRa modem "locks" to the preamble, the end of the preamble is signaled by the "Reverse Chirp" shown in Figure 1. Data transmission then begins, which has a series of "symbols" that function much like M-ARY FSK symbols, but occur on Chirps, see Figure 2. Another powerful feature of LoRa is the ability to demodulate several "orthogonal" or simultaneous signals of the same frequency, as long as they have different chirp change rates. In the data sheet, the LoRa Chirp change rate is called the spread factor (Spread Factor). The higher the spread factor, the slower the Chirp change. Semtech's SX1301 chip supports this feature and has the ability to decode many LoRa Chirps simultaneously, a feature that makes it possible to create large networks. Building such a LoRa network or system requires a lot of development. Going from LoRa to a wireless system is like going from a BPSK wireless chip to a WiFi network. OSI Layer 2 and above functions for large networks include gateways, repeaters, addressing, adaptive data rates, message retries, message acknowledgments, and high-capacity OFDM downlink signaling, which are functions of systems such as LoRaWAN and Symphony Link. LoRa Alliance The LoRa Alliance was founded in 2015 to standardize the MAC function of the LoRa network. The LoRa Alliance developed the LoRaWAN protocol to facilitate mobile network operators using unlicensed spectrum to communicate with IoT devices on their networks. Some details about LoRaWAN are listed below: LoRaWAN is a server-side implementation of a multi-access protocol designed to reduce collisions for a large number of endpoints. It requires a server application to run the MAC function on the network connection; LoRaWAN network architecture usually adopts a star topology, where the gateway is a transparent bridge that relays messages between the end device and the backend central network server; the client logic is built into the network in a server; it is primarily designed for uplink-only applications with multiple endpoints, or applications that only require a small number of downlink messages (limited by the number of applications or endpoints); gateways in the same network need to be synchronized; end-devices and Communication between gateways is distributed over different frequencies and data rates. There is a trade-off between transmission distance and data rate (that is, the longer the transmission distance, the lower the data rate); Different data rates do not interfere with each other and create a set of "virtual" channels to increase the capacity of the gateway; LoRaWAN network server Data rate and RF output per end device managed through an Adaptive Data Rate (ADR) scheme, which is typically updated every 24 hours; Multi-layered security/encryption (EUI64 at network level and application level and EUI128 keys specific to the device ); AES CCM (128 bits) is used for encryption and authentication; The working range is within the range of 1% and 10% of the transmission time duty cycle ETSI, working in the 868 band; According to the draft, the B-type downlink node can be Polling a beacon from 1 second to 128 seconds (now using the engineering prototype provided by IBM's LMiC), the beacon period is 128 seconds (2^n), where n is 0 to 7; antenna diversity, because all gateways listen to the same uplink channel. LoRa Technology Applications Some companies are using all LoRa technology and LoRaWAN technology in interesting ways.
Chinese bike-sharing company OfO, which has equipped its bikes with LoRa devices and radio-frequency technology to determine the location of bikes, operates in more than 180 cities in China. Another example of LoRa network utilization comes from PNI Sensors in Santa Rosa, California. PNI uses LoRaWAN-based wireless connectivity to provide real-time city parking data, making it easier for drivers to find available parking spaces for on-street and off-street public and private parking management. The ultimate goal is to reduce traffic congestion and carbon emissions, which are caused by drivers repeatedly turning back and forth to find a parking space. Many industries are utilizing the open LoRaWAN IoT device standard, including agriculture (for irrigation/water level monitoring and pest control), utilities (for smart meters, lighting and energy management scenarios) and building construction (for building door and window sensors and Building Structural Health Applications).
There are also many companies that do LoRa networks that are not based on LoRaWAN. Deploying IoT devices with LoRa modules If you want to build on a public network owned and operated by an operator, LORAWAN is a very good choice, there are a lot of hardware and network servers providing services in this field, so there are many options is also a Very big advantage. However, the process of developing and deploying a system around LORAWAN is quite complicated. If you do not have much professional knowledge or experience in radio frequency protocols or wireless systems and planning, this will be a challenge. You also need to consider whether deploying a LORAWAN network can meet need. In some cases it may be better to use a custom protocol, where all you have to do is send the data to a node already written to link to the cloud. That's all for today's sharing. EBYTE people are committed to better assisting the development of IoT, intelligence, and automation every day, improving resource utilization, more products and more information. Interested partners can log in to us Visit the official website of Ebyte to understand, and there is also online customer service to answer questions!
"Those things" about LoRa, how many LoRa terminal devices do you know?
What is lora? LoRa must be familiar to everyone. It is an ultra-long-distance wireless transmission scheme based on spread spectrum technology developed by Semtech in the United States. Due to its unique modulation method,bluetooth Wireless Module it has low power consumption, long distance and high flexibility. , so the name "LoRa" (Long Range, meaning long distance). At present, LoRa devices mainly operate in the global free frequency bands, including 433, 868, 915 MHz and so on.
In addition, we also need to understand the concepts related to lora. Today we will talk about LoRa's "those things." LoRa modulation technology LoRa is a modulation technology from a technical point of view. Compared with similar technologies, Provide longer communication distance. LoRa modulation is based on spread spectrum technology, a variant of linear modulation spread spectrum (CSS), with forward error correction (FEC). LoRa significantly improves receiver sensitivity and, like other spread spectrum techniques, uses the entire channel bandwidth to broadcast a signal, making it more robust to channel noise and insensitivity to frequency offsets due to the use of low-cost crystals. LoRa can modulate the signal 19.5dB below the noise floor, while most frequency shift keying (FSK) requires a signal power of 8-10dB above the noise floor to be correctly modulated.
LoRa modulation is a physical layer (PHY) that can be used for different protocols and different network architectures - Mesh ad hoc network, Star, point-to-point transmission, etc. The difference between LoRa and LoRaWAN is that LoRa modulation is PHY, and LoRaWAN is MAC protocol, which is used for high-capacity, long-distance and low-power star network. The LoRa Alliance is standardizing WiFi Wireless Module Low Power Wide Area Network (LPWAN). The LoRaWAN protocol is optimized for low-power, battery-powered sensors, including different levels of end nodes to optimize the balance between network latency and battery life. The LoRaWAN protocol is fully bidirectional, built by security experts to ensure reliability and security. The LoRaWAN architecture also easily locates moving objects for asset tracking, the fastest growing application in the IoT. Major telecom operators are deploying LoRaWAN as a nationwide network, and the LoRa Alliance is standardizing LoRaWAN to ensure that different national networks are interoperable.
LoRa Gateway LoRa Gateway is designed for long-distance star architecture and used in LoRaWAN system, multi-channel, multi-modulation transceiver, multi-channel demodulation at the same time, due to the characteristics of LoRa, it can even demodulate multiple signals on the same channel at the same time. The LoRa gateway uses RF devices different from terminal nodes, has higher capacity, and acts as a transparent bridge to relay messages between terminal devices and central network servers. LoRa gateways are connected to network servers through standard IP connections, and LoRa end devices use single-hop wireless communication to one or more gateways. The communication of all terminal nodes is generally two-way, but it also supports multicast function operations, software upgrades, wireless transmission or other mass release of messages, which reduces the wireless communication time. Depending on the required capacity and the installation location (home or tower), there are different gateway versions. LoRa Concentrator The terms LoRa Gateway and LoRa Concentrator are both used, but they are equivalent components in a LoRa system. In other industries, the definitions of gateway and concentrator mean different components.
LoRa Anti-interference Capability The LoRa modem can suppress co-channel GMSK interference up to 19.5dB, or in other words, it can accept a signal 19.5dB lower than the interference signal or the noise floor. Because of such strong anti-interference, the LoRaTM modulation system can not only be used in frequency bands with high spectrum utilization, but also in mixed communication networks to expand coverage when the original modulation scheme in the network fails. LoRa's data rate LoRaWAN defines a specific set of data rates, but the end chip or PHY can have multiple options. The SX1272 chip supports data rates from 0.3 to 37.5kbps, and the SX1276 chip supports 0.018 to 37.5kbps. LoRa End Node A LoRa End Node is the part of the LoRa network that performs sensing or control. They are battery powered at a distance. These end nodes establish communication with LoRa gateways (concentrators or base stations) using the LoRaWAN network protocol. LoRa Adaptive Data Rate (ADR) ADR is a method that changes the actual data rate to ensure reliable packet delivery, optimal network performance, and capacity scaling. For example, nodes closer to the gateway use higher data rates (reducing transmission time) and lower output power. Only nodes at the very edge of the link budget use the lowest data rate and maximum output power.
The ADR method can adapt to changes in the network infrastructure and support varying path losses. In order to maximize the battery life of end devices and the overall network capacity, the LoRa network infrastructure manages the data rate and RF output of each end device individually by implementing ADR. LoRa has quickly been recognized by the market due to its low power consumption, long-distance and high flexibility. Many representative products of Ebyte are based on LoRa spread spectrum technology. In order to further reduce costs, Ebyte also launched A new generation of LoRa solution, more cost-effective, welcome new and old friends to buy!
WiFi Wireless Module has a wide range of application scenarios
WiFi Wireless Module has a wide range of application scenarios and can be applied to various fields and industries. The following are some common application scenarios of WiFi Wireless Module:
Smart home: WiFi Wireless Module can be used in smart home systems to realize interconnection and remote control between devices. By connecting to a home WiFi network, users can remotely control home devices such as smart lamps, smart sockets, smart door locks, etc. through smartphones or other devices.
Industrial automation: WiFi Wireless Module can be embedded in industrial equipment to realize communication and data transmission between equipment. It can be used to remotely monitor and control industrial equipment, realize remote maintenance and management, and improve production efficiency and operational safety.
Smart health: WiFi Wireless Module can be embedded in health monitoring devices, such as smart bracelets, smart scales, etc., to realize data transmission and interconnection with smart phones or cloud platforms. Users can monitor and manage their own health through the mobile app.
Logistics and warehouse management: WiFi Wireless Module can be used in logistics and warehouse management systems to realize remote monitoring and management of equipment and systems. It can be used to track and manage logistics transportation vehicles, warehouse goods, etc., and improve the efficiency and accuracy of logistics operations.
Hotels and commercial places: WiFi Wireless Module can be used for wireless network coverage and management in hotels and commercial places. It can provide wireless network connection to meet the needs of customers and employees for the Internet, and supports functions such as user authentication and flow control.
Smart city: WiFi Wireless Module can be used in various aspects of smart city construction, such as intelligent transportation system, intelligent public facility management, intelligent parking system, etc. It can provide wireless connection and communication capabilities within the city, and realize the intelligence and interconnection of urban facilities.
In general, the application scenarios of WiFi Wireless Module are very wide, covering many fields such as home, industry, health, logistics, hotels, commercial places, and smart cities. It provides reliable wireless communication and interconnection capabilities for devices and systems, and promotes the development of the Internet of Things and the realization of intelligence.