The background of the formation of "Bluetooth" is as follows:1In May, 1998, five famous manufacturers, such as Ericsson, Nokia, Toshiba, IBM and Intel, put forward Bluetooth technology when jointly carrying out the standardization activities of short-distance wireless communication technology, with the aim of providing a short-distance and low-cost wireless transmission application technology. The five vendors also set up a Bluetooth Special Interest Group to make Bluetooth technology the future wireless communication standard. Chip overlord Intel is responsible for the development of semiconductor chips and transmission software, Ericsson is responsible for the development of radio frequency and mobile phone software, and IBM and Toshiba are responsible for the development of notebook computer interface specifications. 1999 In the second half of the year, five famous industry giants, including Microsoft, Motorola, Sankang, Lucent and Bluetooth Task Force, initiated the establishment of a Bluetooth technology promotion organization, which set off a worldwide "Bluetooth" craze. The global industry is about to develop a large number of applications of Bluetooth technology, which makes Bluetooth technology present an extremely broad market prospect, indicating that a magnificent global wireless communication wave will be ushered in at the beginning of 2 1 century.
Bluetooth and infrared are both a kind of wireless transmission, and infrared has been used for a long time. Bluetooth is a wireless transmission mode that has developed rapidly in recent years.
Compared with infrared, Bluetooth has several advantages: the transmission speed of 1 is about 0 times that of infrared 10, and the effective distance is long. Generally, 10 m 3 is stable, and 4 does not need linear transmission.
Infrared data communication technology
What is IRDA?
IRDA is the abbreviation of infrared data association, and a series of infrared data communication standards formulated by IRDA form the basis of infrared data communication technology. Infrared communication technology is a point-to-point data transmission protocol, which replaces the traditional connecting cable between devices. The communication distance is generally between 0- 1 m, and the fastest transmission rate can reach 16Mbps. The communication medium is near infrared with a wavelength of about 900 nanometers.
Characteristics of infrared communication technology
■ It is a wireless connection technology widely used in the world at present, supported by various software and hardware platforms;
■ Wireless data transmission and reception can be realized through the mutual conversion between data electric pulse and infrared pulse.
■ Mainly used to replace point-to-point cable connection;
■ The new communication standard is compatible with the earlier communication standard;
■ Small angle (within 30-degree cone angle), short distance, point-to-point linear data transmission, strong confidentiality;
■ High transmission rate. At present, the FIR technology with 4M rate has been widely used, and the VFIR technology with 16M rate has been released.
Application of infrared data communication technology
Infrared communication technology is commonly used in the following equipment:
■ Notebooks, desktop computers and palmtop computers;
■ Computer peripherals, such as printers, keyboards and mice;
■ Telephone, mobile phone, pager;
■ Digital cameras, calculators, game consoles, set-top boxes, watches;
■ Industrial equipment and medical equipment;
■ Network access devices, such as modems.
Recognition by manufacturers and consumers
Infrared communication technology has been supported and adopted by many software and hardware manufacturers around the world, and the mainstream software and hardware platforms have provided support for it. Infrared technology has been widely used in mobile computing and mobile communication equipment, and the huge installed capacity makes infrared wireless communication technology have a huge user base.
Implantation cost
Because most system chips have infrared communication control circuits, it is only necessary to add infrared transceiver devices and implant infrared functions into the system. This greatly reduces the implantation cost of infrared communication, and mass production can control the implantation cost within $3.
disadvantaged
■ Short communication distance, unable to move during communication, and communication is interrupted when encountering obstacles.
■ The widely used SIR standard has a low communication rate (1 15.2kbit/s).
■ The main purpose of infrared communication technology is to replace wired connection for wireless data transmission, with single function and poor expansibility.
What is Bluetooth?
Bluetooth is a technical standard for short-range wireless data communication proposed by Toshiba, Ericsson, IBM, Intel and Nokia in May 1998. It can realize wireless data and sound transmission from single point to multipoint within the radius of 10 meter, and the data transmission bandwidth can reach 1Mbps. The communication medium is electromagnetic wave with frequency between 2.402GHz and 2.480GHz.
Characteristics of Bluetooth communication technology
■ Bluetooth works in the globally open 2.4GHz ISM (i.e. industrial, scientific and medical) frequency band;
The frequency band is divided into several frequency hopping channels by using frequency hopping spread spectrum technology. In a connection, the radio transceiver constantly "hops" from one channel to another according to a certain code sequence;
■ One Bluetooth device can establish connection with seven other Bluetooth devices at the same time;
■ The data transmission rate can reach1mbit/s;
■ Low power consumption and good communication security;
■ It can be connected across obstacles within an effective range without special communication angle and direction requirements;
■ Support voice transmission;
■ Networking is simple and convenient
The Use of Bluetooth Communication Technology
Bluetooth technology is a new technology and has not been widely used. At present, many Bluetooth devices are still in the laboratory testing stage. But what is certain is that in the future, most devices with infrared wireless data communication function can use Bluetooth technology to realize wireless connection. At the same time, the network characteristics and voice transmission technology of Bluetooth technology enable it to realize some specific functions that infrared technology cannot, such as wireless telephone and networking of multiple devices.
Recognition by manufacturers and consumers
Bluetooth technology has been responded by more than 2000 enterprises, so it has great development and production capacity. Bluetooth has a high popularity and consumers are very interested in this technology.
Implantation cost
At present, Bluetooth devices on the market are still relatively rare. Bluetooth adapters with USB interface, Bluetooth PC cards and Bluetooth mobile phones have been marketed with higher prices. It can be seen that the implantation cost of Bluetooth in the early stage of development is still relatively high. However, it is estimated that the implantation cost after mass production can be below $30. In the mature period of Bluetooth technology, the implantation cost should be controlled within 10 USD.
disadvantaged
Bluetooth is a technology that is not yet fully mature. Although the description is attractive, it still needs strict inspection in actual use. The communication speed of Bluetooth is not very high, and it may also affect its development in today's era of data explosion.
At present, the mainstream software and hardware platforms do not provide support for Bluetooth, which makes the application cost of Bluetooth higher and the popularization more difficult.
ISM band is an open band, which may be interfered by microwave ovens, cordless phones, scientific research instruments, industrial or medical equipment.
abstract
Overview of popular wireless technology
Maximum data rate range radius (meters) Cost Voice network support data network support
Ieee 802.11b11Mbps100 ~ 300 is high.
Bluetooth1Mbps10 ~100 is generally.
HomeRF 1.6 Mbps
It can be increased to 1 1Mbps 50, usually.
IrDA 16 Mbps 2 Low No Yes
To sum up, it can be seen that Bluetooth has obvious technical advantages and should be an alternative technology for infrared wireless data communication. However, because Bluetooth technology is still in the early stage of development and restricted by various conditions, Bluetooth technology has some problems, such as high implantation cost, few communication objects, low communication rate and immature technology. Its development and popularization need to be tempered by the market and tested by time, and its own technology needs to be constantly improved and improved. On the other hand, infrared communication technology has the characteristics of mature technology, low cost, good compatibility and fast communication speed, which has been widely supported by software and hardware and is being widely used. Although Bluetooth technology may eventually replace infrared communication technology, this process may take a long time, during which infrared communication technology will still play an important role in the field of short-distance wireless data communication.
Infrared technology (IRDA) and Bluetooth technology have their own advantages and disadvantages. In the future, they will be in a competitive, mutually reinforcing and complementary development trend. Bluetooth technology is difficult to shake the stable position of infrared technology in a short time. In fact, the coexistence of infrared technology and Bluetooth technology constitutes a perfect short-distance wireless data communication technology system.