Bluetooth and wireless network
(2010-03-10 15:45:59) - - We are currently in the case of "overline". In our office, the usual situation will have an Ethernet socket within a few meters. At home, the situation is even worse - a large pile of long shortlines behind the computer connects large and small peripherals - printers, scanners, modems, speakers, game poles, etc., and more It is always easy to connect, such as digital cameras to save photos, MP3 players want to exchange files, handheld to make file synchronization, pull this line to insert it, but it is not easy. ---- Trouble is not only these, not only these, now high-speed access equipment has become more and more popular - what isDN, ADSL, Cable Modem, but face multi-phone, multiple Internet equipment, can not move Run, can you buy several access devices? ---- All these issues, the answer is pointed to one. That is to use air to replace the wired wireless solution. ---- How to transfer information in your phone to your PC? In addition to directly take the data cable connection, we can also have many options: two-way paging network, circuit-switched cellular mobile communication system, cellular digital packet switched CDPD (Cellular Digital Packet Data), Homerf, 802.11b Wi-Fi, 128-Kbit / S Ricochet Network, Ericsson's experimental EDGE cellular system (Edge is a packet-switched mobile technology similar to GPRS, but the highest speed can be 384kbit / s , Higher than GPRS, there is Bluetooth technology, and so on. ---- In all these nouns, the visibility of possible Bluetooth technology is highest. After the WAP's boom is gradually retracted, the name of Bluetooth is often mentioned. Bluetooth, directly translated from English words Bluetooth, in fact, this name is integrated from Harald Bluetooth - a Danish king in Denmark in the 10th century, Norway. The inventors undoubtedly hope that Bluetooth technology can closely combine mobile phones, laptops, and handheld devices like this king. ---- Bluetooth technology is a wireless personal network (PAN) technology, its initiator includes Ericsson, IBM, Intel, Nokia and Toshiba. As an open standard, Bluetooth can provide digital speech and data transmission within a short distance, which can support a pair or multipoint application between mobile devices and desktop devices. ---- The original intention of this technology is to establish a wireless connection between the PC and the mobile phone, but with the standards of the standard, people give more functions for it - connected digital cameras , Printers, other peripherals, and even a car, later even Microsoft and Intel also expressed the development of the Bluetooth on the software and hardware platform. ---- As a technology, Bluetooth technology can provide up to 720K speed transmission, allowing information to share information within 10 meters; if power is large enough, it is said to be extended to 100 meters. Bluetooth is not like an infrared transfer protocol (IrDa), and the other side must be aligned between the devices that require transmission, it uses the wireless microwave in the whole direction to transmit the wall and other non-metallic disorders.
---- With Bluetooth technology, with JINI technology such as Sun, we can use their printers while waiting for friends or customers (Hewlett-Packard and Nokia companies are working directly. Mobile phone printing web content printer); can send photos directly to the distant relatives and relatives directly using digital camera; our mobile phone can automatically receive flight information from the airport during airport ... In short, When an electronic device opens or enters the valid area, it can accept the relevant information. ---- But to achieve this beautiful foreground, Bluetooth still needs to span many obstacles. Some analysts pointed out: --- 1. Each Bluetooth device requires a Bluetooth chip that needs to be compatible with each other, which requires different manufacturers of manufacturers. At the same time, the Bluetooth chip based on CMOS technology, how to avoid interference with other signals, how to control errors, power consumption, appropriate output power, and acceptable sensitivity, etc., need to be resolved. ----2. The compatibility of technology is just one aspect. On the other hand, each Bluetooth chip requires the payment fee for users. More importantly, these chips are not very suitable - now, a Bluetooth PC card requires approximately $ 100, and the manufacturer intends to reduce the price to $ 5 in a few years. ---- 3. Ericsson has introduced a headset with a Bluetooth module. This way you don't have to drag a wire below the chin and call your phone directly. But the problem is that if you still want to talk to the PC or other handheld devices, how do this relationship solves? ---- And Bluetooth is better, and can only solve the problem in a small environment, and it needs a large environment to cooperate. This is the technology of wireless networking. At present, the standard wireless networking is still in the state of the two armies - 802.11b and Homerf. Before 802.11b, there are more than 70 companies of Dell, 3COM, Cisco, Sony, Apple and Lucent, and Homerf, 80 companies such as HP, Compaq, Intel, Motorola and Siemens. Before they divided high, the market is inevitably waiting for the situation waiting to wait and see. While enjoying the benefits of competition, we must first endure the chaos brought by competition. ---- Two techniques, 802.11b has a high-speed transmission rate of 11M BPS but the price is more expensive, while Homerf is low (1.6M bps) but the cost is also low. At the same time, since the high bandwidth provided by 802.11b is the cost of dividing the data into a TCP / IP package, this will have a bad impact on the playback of "streaming media". Therefore, it is relatively regarded that HOMERF supports support and image data support 802.11b. ---- According to reports, FCC (Federal Communications Commsion, US Federal Communications Commission) will allow Homerf to increase the rate to 10m this summer. One side of the 802.11b also said that it will also speed up to 22M and will support voice calls, and the price will also be reduced to Homerf. ---- In terms of application conditions, both standards are also difficult to divide. Currently, 802.11b terminals can be used in 30 airports and major hotels in the United States. According to the investigation of PC Data Reports, 95% of wireless computer products currently selling home are based on Homerf protocol. ---- Analyst believes that Internet equipment manufacturers and service providers, such as AT & T and Pacific Bell, etc., who will win the important weight.
At the same time, speech support can be achieved well, and it is also an important factor. Because ISP can of course hope that their high-speed connection (whether DSL or Cable is capable of fully replacing the functionality of the telephone line. ---- Two standards are like Bluetooth, based on the 2.4GHz band, that is, on this frequency band, will be mixed. Although both agreements claim that they will be very compatible with Bluetooth, who can guarantee that they will not interfere with each other? ---- When two protocols are unknown, the updated technology has not slowed down. Recently, the two US companies Radiata Inc and Atheros Communications announced that the chipset for faster wireless LAN protocol IEEE 802.11a will be launched this year, the price is about $ 35. The data transfer rate of 802.11a will be increased to 54M BPS. Atheros is even more claims that their chipset is at the "Turbo Mode", the rate can reach 72M BPS. For 802.11a, greater significance may not only increase the transmission rate. 802.11a will work in the frequency of 5GHz, which avoids the crowded 2.4GHz band, which is undoubtedly good news for those who should use Bluetooth and Wireless LANs. ---- In Europe, Ericsson and Nokia in supporting another standard called Hyperlan II, which has the same highest bandwidth as 802.11a. ---- In fact, the increasing hot wireless network does not mean that it can solve any new problems. However, wireless networks can provide greater flexibility, liquidity, and save costs and effort spent on integrated wiring. The simplicity and convenience of the wireless network will also greatly promote the process of home networking. It is predicted that this year's wireless network will easily break through $ 1 billion. It is not difficult to envision, HP's E-Services, Sun's Net Effect and Microsoft's service driver's next-generation Internet described, will be based on the wireless network. Now we can confirming such a future network architecture - high-speed fiber network constitutes the main business and home networks, and a large number of mobile devices will become the main terminal, and then supplemented Long-distance mobile data communication. --- With the popularity of wireless networks, there will be many other business opportunities, and stimulate the sales of related equipment, this situation has been reflected in the sales of laptops.
---- Compared with the sales growth of the desktop PC, the sales of laptops have maintained a good momentum last year. The sales of laptops in 2000 increased by 21% (desktop only increased by 1.6% of the district), and the price did not drop, according to NPD INTELECT, the average retail price of notebook in the fourth quarter of 2000 is $ 1725, and The same period in 1999 is $ 1709. Among them, the huge promotion of wireless networks cannot.
---- Wireless network will bring changes, I am afraid it is still difficult to expect.
