“The importance of wireless communication is self-evident. For wireless communication technology, we apply it every day. In order to enhance everyone’s understanding of wireless communication, this article will introduce the top 10 wireless communication technologies and talk about how these wireless communication technologies contribute to the growth of the Internet of Things.
The importance of wireless communication is self-evident. For wireless communication technology, we apply it every day. In order to enhance everyone’s understanding of wireless communication, this article will introduce the top 10 wireless communication technologies and talk about how these wireless communication technologies contribute to the growth of the Internet of Things.
Among the communication technologies that realize the Internet of Things, Bluetooth, zigbee, Wi-Fi, GPRS, NFC, etc. are the most widely used wireless technologies. In addition to these, there are many wireless technologies that work silently in their respective suitable scenarios and play an indispensable role. The author of this article will introduce the real Internet of Things communication technology through the advantages and disadvantages of the top ten common wireless communication technologies and application scenarios.
1. The technical characteristics of Bluetooth
Bluetooth is a wireless technology standard that can realize short-distance data exchange between fixed devices, mobile devices and building personal area networks. Bluetooth can connect multiple devices to overcome the problem of data synchronization. Bluetooth technology was originally created in 1994 by the telecommunications giant Ericsson. Today, Bluetooth is managed by the Bluetooth Technology Alliance, which has more than 25,000 member companies worldwide, which are distributed in multiple fields such as telecommunications, computers, networks, and consumer electronics.
The characteristics of Bluetooth technology include the use of frequency hopping technology to resist signal fading; fast frequency hopping and short packet technology can reduce co-frequency interference and ensure the reliability of transmission; forward error correction coding technology can reduce the influence of random noise during long-distance transmission; Use FM modulation to reduce the complexity of the equipment, etc. Among them, the Bluetooth core specification is to provide two or more piconet connections to form a distributed network, allowing specific devices to automatically and simultaneously play the roles of master and slave in these piconets. The Bluetooth master device can communicate with up to seven devices in a piconet, and the roles can be switched between the devices through the protocol, and the slave device can also be converted to the master device.
2. Technical characteristics of ZigBee
Unlike Bluetooth technology, ZigBee technology is a short-distance, low-power, and inexpensive wireless communication technology. It is a wireless network protocol for low-speed and short-distance transmission. This name comes from the bee’s eight-character dance, because bees rely on the “dance” of flying and “zig” shaking their wings (bee) to convey the location information of pollen to their companions, which means that bees rely on this method. It constitutes the communication network in the group.
The characteristics of ZigBee are close range, low complexity, self-organization, low power consumption, and low data rate. The ZigBee protocol is divided into physical layer, media access control layer, transport layer, network layer, application layer, etc. The layer and media access control layer follow the provisions of the IEEE 802.15.4 standard. ZigBee technology is suitable for automatic control and remote control, and can be embedded in various devices.
3. Technical characteristics of Wi-Fi
Wi-Fi is very common in our lives. Almost all public places in first-tier cities have wireless networks. This is due to its low cost and transmission characteristics. Wi-Fi is a technology that allows Electronic devices to connect to a wireless local area network. It usually uses 2.4G UHF or 5G SHF ISM radio frequency bands. Connecting to a wireless local area network is usually password-protected; but it can also be open, which allows any Devices within WLAN range can be connected.
Since the frequency band of the wireless network does not require any telecommunications operating license worldwide, WLAN wireless equipment provides a wireless air interface that can be used worldwide with extremely low cost and extremely high data bandwidth. Users can quickly browse the web in the Wi-Fi coverage area, and receive and make calls anytime and anywhere. With Wi-Fi function, we can make long-distance calls, browse the web, send and receive emails, download music, transfer digital photos, etc., no longer need to worry about slow speed And the problem of high cost.
Wireless networks are more and more widely used on handheld devices, and smart phones are one of them. Different from the Bluetooth technology applied to mobile phones earlier, Wi-Fi has a larger coverage area and a higher transmission rate. Therefore, Wi-Fi mobile phones have become a fashion trend in the mobile communications industry in 2010.
4. Technical characteristics of LiFi
LiFi is also called visible light wireless communication. It is a brand-new wireless transmission technology that uses visible light spectrum for data transmission. It was invented by Professor Harald Haas, the chair of the Department of Mobile Communication at the School of Electronics and Communications, University of Edinburgh, UK and the German physicist Harald Haas. LiFi uses already laid equipment to form a device similar to a WiFi hotspot by implanting a tiny chip on the bulb, so that the terminal can access the network at any time.
The biggest feature of this technology is data transmission by changing the flicker frequency of the room lighting. As long as the lights are turned on indoors, the Internet can be accessed without WiFi. It has a wide range of application prospects in smart homes in the future.
5. Technical characteristics of GPRS
We can say that GPRS is very familiar. It is a mobile data service available to GSM mobile phone users and belongs to the data transmission technology in the second generation of mobile communications. GPRS can be said to be the continuation of GSM. GPRS is different from the previous continuous channel transmission method. It is transmitted in packets. Therefore, the user’s cost is calculated in the unit of transmission data, rather than using the entire channel. In theory, it is more Cheap.
GPRS is a technology between 2G and 3G, also known as 2.5G, which lays the foundation for a smooth transition from GSM to 3G. With the development of mobile communication technologies, 3G, 4G, and 5G technologies have been developed, and GPRS has gradually been replaced by these technologies.
6. Technical characteristics of Z-Wave
Z-Wave is an emerging short-range wireless communication technology based on radio frequency, low cost, low power consumption, high reliability, and suitable for networks. It is a wireless networking specification led by the Danish company Zensys. The working frequency band is 908.42MHz (U.S.) ~ 868.42MHz (Europe), using FSK (BFSK/GFSK) modulation mode, and the data transmission rate is 9.6 kbps, which is suitable for narrow broadband applications.
With the increase of communication distance, the complexity, power consumption and system cost of equipment are increasing. Compared with the existing various wireless communication technologies, Z-Wave technology will be the technology with the lowest power consumption and lowest cost. Promoting low-speed wireless personal area networks.
7. Technical characteristics of RF 433
RF 433 is also called wireless transceiver module. It adopts RF technology. It is composed of a single IC RF front-end produced by all-digital technology and ATMEL AVR single-chip microcomputer. It is a micro transceiver that can transmit data signals at a high speed. Wireless transmission data is packaged and error detection is performed. p Error correction processing. The application range of radio frequency 433 technology includes wireless smart terminals such as wireless POS machines, PDAs, security, wireless monitoring of equipment room equipment, and access control systems. Transportation, meteorology, environmental data collection, intelligent community, building automation, PLC, logistics tracking, warehouse inspection and other fields.
8. Technical characteristics of NFC
NFC is an emerging technology. Devices using NFC technology can exchange data when they are close to each other. It is evolved from the integration of non-contact radio frequency identification (RFID) and interconnection technology. It integrates the functions of inductive card reader, inductive card and point-to-point communication, and uses mobile terminals to realize applications such as mobile payment, access control, and identification.
Near field communication technology has realized multiple functions such as electronic payment, identity authentication, ticketing, data exchange, anti-counterfeiting, advertising, etc. It has changed the way users use mobile phones and gradually made their consumption behaviors electronic.
9. Technical characteristics of UWB
UWB is a non-carrier communication technology that uses nanosecond to microsecond non-sine wave narrow pulses to transmit data. UWB was used for short-distance high-speed data transmission in the early days. In recent years, foreign countries have begun to use its sub-nanosecond ultra-narrow pulses for short-distance accurate indoor positioning.
Unlike traditional wireless systems with relatively narrow bandwidths such as Bluetooth and WLAN, UWB can send a series of very narrow low-power pulses over a wide frequency. The wider frequency spectrum, lower power, and pulsed data mean that UWB causes less interference than traditional narrowband wireless solutions, and can provide performance comparable to wired in indoor wireless environments.
10. Technical characteristics of Modbus
Modbus is a serial communication protocol, which was published by Modicon company (now called Schneider Electric) in 1979 for the use of programmable logic controller communication. Modbus has become an industry standard for communication protocols in the industrial field, and is now a common connection method between industrial electronic devices. The Modbus protocol is a master/slave architecture protocol. There is a master node, and other nodes that use Modbus protocol to participate in communication are slave nodes. Each slave device has a unique address. In serial and MB+ networks, only the node designated as the master node can initiate a command.
There are many modems and gateways that support the Modbus protocol, because the Modbus protocol is simple and easy to replicate. Some of them are specially designed for this protocol, but the designer needs to overcome some problems including high latency and timing.