Bluetooth is a radio technology that supports short-range communication between devices. Wireless information exchange can be performed between mobile phones, PDAs, wireless headsets, notebook computers, and related peripherals. Using “Bluetooth” technology can effectively simplify the communication between mobile communication terminal devices, and also simplify the communication between the devices and the Internet, so that data transmission becomes more rapid and efficient. Bluetooth adopts decentralized network structure and fast frequency hopping and short packet technology, supports point-to-point and point-to-multipoint communication, and works in the 2.4GHz ISM (ie industrial, scientific, medical) frequency band that is commonly used in the world. Its data rate is 1Mbps. The time division duplex transmission scheme is used to realize full duplex transmission.Bluetooth technology was originally created by Ericsson. On May 20, 1999, industry leaders such as Sony Ericsson, IBM, Intel, Nokia and Toshiba established the Bluetooth Special Interest Group to formulate Bluetooth technology standards. In 1998, Ericsson hoped that the wireless communication technology could be unified and named “Bluetooth”.The characteristics of Bluetooth technology can be summarized as follows: It is applicable worldwide, can transmit voice and data at the same time, can establish a temporary peer-to-peer connection (Ad-hoc Connection), has good anti-interference ability, and the Bluetooth module is small in size , easy to integrate, low power consumption, open interface standard, low cost.
WiFi (Wireless Fidelity, wireless fidelity technology), the IEEE 802.11 protocol, is a short-range wireless transmission technology that can support radio signals for Internet access within a range of hundreds of feet. The first version of WiFi was published in 1997, which defined the medium access control layer (MAC layer) and the physical layer.It specifies the basic network structure and basic transmission medium of wireless local area network, and standardizes the characteristics of the physical layer (PHY) and the medium access layer (MAC). The physical layer uses infrared, DSSS (Direct Sequence Spread Spectrum) or FSSS (Frequency Modulated Spread Spectrum) technology. In 1999, the IEEE 802.11a and IEEE 802.11g standards were added. Its transfer rate is up to 54 Mb/s. It can widely support services such as data, image, voice and multimedia.Advantages of WiFi technology: wide coverage of radio waves, fast transmission speed of WiFi, health and safety, WiFi applications are now very common, more and more electronic products supporting WiFi, such as mobile phones, MP4, computers, etc., have basically become Mainstream standard configuration.There are two main shortcomings of wifi: one is limited coverage; the other is poor mobility.
The smart home industry may become a popular field of Bluetooth
Today, Bluetooth-enabled devices are everywhere. In fact, Bluetooth is an important communication method common in life. Compared with ZigBee, Z-wave, WiFi and other technologies that “appear less” in smart homes, Bluetooth is also a mainstream communication technology for wireless smart homes. Bluetooth technology has been widely used, and products integrating this technology include mobile phones, computers, headphones, speakers, automobiles, medical equipment, and so on.As we all know, Bluetooth is a point-to-point communication method that supports radio technology for short-distance communication of devices (generally within 10m, Bluetooth 4.0 extends to 100m). Wireless information exchange between devices. The use of “Bluetooth” technology can effectively simplify the communication between mobile communication terminal devices, and can also successfully simplify the communication between devices and the Internet, so that data transmission becomes more rapid and efficient, and the road for wireless communication is widened. The design scheme of smart home based on bluetooth technology, using this solution, can make data acquisition and home security monitoring flexible and convenient, get rid of the shackles of wiring system, and the frequency hopping technology of bluetooth improves the anti-interference ability of the system to a certain extent.In addition, Bluetooth devices are small and easy to carry, so in the field of smart homes, Bluetooth technology is more suitable for some devices that are used privately at close range, such as smart bracelets, smart watches, and smart scales.Different from mainstream smart home companies such as IoT sensing and technologies such as ZigBee, Bluetooth technology is obviously better at small devices that “play alone”. Bluetooth technology can be directly inserted into smaller smart home devices, especially after the improvement in security and energy consumption . It is also used in many smart home items.Of course, Bluetooth smart is not perfect – although its transmission distance can reach 60 meters, the premise is that the chip manufacturer provides sufficient support. For example, for rival mobile devices, the distance is basically limited to 10 meters~ within 30 meters. In addition, if the amount of data is large, the transmission efficiency of Bluetooth Smart will be a bit slow and it will take a long time. Others include the lack of channel compatibility, reliability and security. Leakage incidents are very common, and true “roaming” cannot be achieved. There is no network self-healing function, which will greatly reduce the operation of equipment for smart homes based on wireless networks. efficiency, and the Bluetooth anti-interference ability is poor. In addition, due to its short transmission distance, the network carrying capacity is relatively low, and the network scale of the new standard generally cannot exceed 300, so it is not suitable for setting up a huge home network. These are all issues that need to be addressed next.
Gradually becoming mainstream, wifi leads the smart home
The general trend of smart home has a broad market: The smart home market dominated by wireless technology will usher in rapid growth in the next five years. In 2018, the smart home market will be worth $25 billion, according to the research firm. However, due to the limitations of technology and price, smart homes have not been able to show all their characteristics, and it is not realistic to expect smart homes to be popularized soon. At present, smart home appliances are limited to high-end residences, but in the future, with the penetration of bottom-level suppliers and terminal equipment, smart homes will benefit the public.
No matter what kind of wireless communication technology the smart home network is composed of, the premise is to connect the home network, which happens to be the advantage of Wi-Fi. Today, most spaces in the world support Wi-Fi networking. This will greatly reduce the development difficulty of Wi-Fi technology in the smart home field.Compared with Bluetooth and other technologies, Wi-Fi has its own obvious shortcomings, such as relatively high power consumption, relatively low security and anti-interference, and the carrying capacity of network equipment is also very limited, but “short and powerful” Wi-Fi It also has its own advantages. Wi-Fi has a wide coverage of radio waves with a radius of up to 100 meters. It can be used in homes, offices, and even entire buildings. At the same time, the transmission speed of Wi-Fi without wiring is also very fast, which can reach 11mbps. , the amount of radiation from Wi-Fi devices is also very small, and it does not pose a threat to human health as feared.Finally, although the home equipment carried by the Wi-Fi network is limited, if you want to connect all the home equipment and realize the comprehensive intelligence of the home equipment, it is also “catch a duck to the shelf”, but “lightness” also has the advantage of “lightness”. From another point of view, WIFI just has the flexibility and mobility that other wireless communication technologies do not have, which is also an important factor for it to be welcomed by the majority of smart home manufacturers.
The popularization of smart home Wi-Fi makes great contribution: with the rise of light intelligence and micro intelligence, WIFI shows its bright spot in smart home applications. Different from companies such as IoT Sensing who are devoted to wireless technologies such as Bluetooth, light smart home manufacturers prefer to use home Wi-Fi to directly connect home devices, and put Wi-Fi modules into switches and sockets. The entrance of the light smart home and a control center can realize the intelligent control of home equipment.