CDMA Code-Division Multiple Access (Code Division Multiple Access)
Qualcomm developed CDMA is a digital cellular (Digital Cellular) type communication technologies, is also a 3G system communications technology base.
TDMA and GSM, or different, CDMA communication terminal will be digitized signals, the can take advantage of all available spectrum to spread transmission, each message transmission have been assigned a serial number.
3G systems is to CDMA-based access technology for communication, CDMA using multi-group code, in the same channel to send multiple messages, the receiver will only accept a special set of their own voice and data encoding, even within the same channel other different code signals exist, it will not affect the reception quality.
To CDMA-based 3G technology, mainly European regulation of WCDMA, the U.S. rules of cdma2000 and mainland China, the development of TD-SCDMA. These three organizations are regulated by the International Telecommunications IMT-2000 technical standards.
With CDMA standards-based Personal Communications Services (Personal Communications Services; PCS) network provides a 9.6Kbps and 14.4Kbps transfer rate, while including Lucent and Northern Telecom and other telecommunications companies are actively developing a new generation of CDMA, not only the transmission speed can be upgraded to 2 Mbps, but also solved the original and current specifications IS-95 incompatibility issues.
In terms of the communication equipment, CDMA mobile phone and most people now use cell phones, GSM cell phone that is, to compare with the radiation is small, call clear, data transmission and so on.
PCS networks than any other digital cellular communications standards, such as the time-multiple-access (Time Division Multiple Access; TDMA) offer better call clarity (call clarity) and security, but also there are many value-added services, such as callerID, call waiting (call waiting) and voice mail functions, and available to users with mobile phone (handset) send and receive short text messages and paging messages capability. Due to the high transfer rate of CDMA and diversification of services in the United States has gradually prevailed.
Cell Broadcast SMS Broadcast Service
Cell broadcasting services are broadcasting way digital information sent in the duplication of a region so that all the users, making two-way communication outside of the time, can receive these broadcasts messages on a regular basis.
In general, the carriers provide stock quotes, weather forecasts, traffic reports, etc., because the recipient no special restrictions on the object, it is broadcast via short message service to reach.
A wide range of applications, such as leisure and entertainment activities in the recreation area to inform the tourism industry of the popular tourist itinerary promotions, cultural and educational sector of the popular books list, daily horoscope, fortune resolution, time-limited discount notification, department store's seasonal uniform auction, anniversary event notifications, exchange gifts notice, to send coupons and other marketing industry, the traditional advertising companies marketing, and marketing, Integrated Marketing Zhi Xiaoye use of the Internet industry, Member Services advised that the activities of this web site, website maintenance, instant messaging notification.
CGI Common Gateway Interface
Web server (WEB SERVER) and application data transfers between the interface specifications. CGI program can be used in any programming language (PROGRAMMING LANGUAGE) production, usually PERL, using the CGI program can read the user's input and generates dynamic HTML Web (WEB PAGE). Most of the commercial web server to provide programming interface (API) to replace the CGI, because CGI will implement the establishment of a stroke every time (PROCESS), the server is a burden.
Chipset PC
Chipset, a group to accomplish a specific function of the chip (CHIP). Motherboard (MOTHERBOARD) on the chipset used to control bus (BUS), memory (MEMORY), and other peripheral devices. |
