International Telecommunication Union (ITU) in May 2000 to determine W-CDMA, CDMA2000, TD-SCDMA, as well as the mainstream of the four WiMAX wireless interface standard, 3G technology into the guiding text of the "2000 International Mobile Communications Plan" (referred to as IMT-2000 ). CDMA is Code Division Multiple Access (CDMA) acronym, is the third generation mobile communication technology-based systems. The first generation of mobile communication system using frequency division multiple access (FDMA) analog modulation, the system is the fundamental flaw of the spectrum utilization low, signaling interfere with voice service. Second-generation mobile communications systems using time division multiple access (TDMA) digital modulation, to increase the capacity of the system, and an independent channel signal transmission, so that system performance greatly improved, but the TDMA system capacity is still limited, handoff Performance does not improve. CDMA system, with its simple frequency planning, system capacity, frequency reuse factor of high anti-multipath capability, good communication quality, capacity soft, soft switching characteristics, such as showing great potential for development. The following were some brief 3G standards:
(1) W-CDMA
Also known as WCDMA, called Wideband CDMA, also known as CDMA Direct Spread, which means broadband Code-Division Multiple Access, which is based on the GSM network developed 3G technology standard proposed by the European broadband CDMA technology in Japan The proposed broadband CDMA technology is basically the same as is currently being further integration. Its main supporter of the GSM system is mainly of European manufacturers, Japanese companies are more or less involved, including Europe and the United States of Ericsson, Alcatel, Nokia, Lucent, Nortel, as well as Japan's NTT, Fujitsu, Sharp , And other manufacturers. The system can be set up in the existing GSM network, the system providers can be moved less transition, and the GSM system very popular in Asia for the new technology acceptance is expected to be high. Therefore, W-CDMA has the inherent advantages of the market. The proposed standard GSM (2G)-GPRS-EDGE-WCDMA (3G) evolution strategy. GPRS is General Packet Radio Service (GPRS), referred to as, EDGE is Enhanced Data rate for GSM Evolution (Enhanced Data Rates for GSM Evolution), referred to as the two technologies called 2.5 generation mobile communication technology.
(2) CDMA2000
CDMA2000 is by the narrow-band CDMA (CDMA IS95) technology developed from broadband CDMA technology, also known as CDMA Multi-Carrier, from Qualcomm Inc. led the North American made, Motorola, Lucent, subsequently joined by South Korea's Samsung are involved in the process, South Korea Now become the dominant standard. The system is the digital standard from the narrowband CDMAOne derived from the original structure CDMAOne directly to upgrade to 3G, low-cost construction. However, the use of CDMA, only Japan, South Korea and North America, CDMA2000 is why supporters of more than W-CDMA. However, the CDMA2000 technology research and development is currently the fastest progress in standards, and many have been the first to launch 3G mobile phone. The proposed standards from the CDMA IS95 (2G)-CDMA20001x-CDMA20003x (3G) evolution strategy. CDMA20001x called 2.5 generation mobile communication technology. CDMA20003x and CDMA20001x the main difference is that the application of multi-carrier technology, so that through the use of three carrier to increase bandwidth. At present, China Unicom is using the program to transition to 3G and has built a network of CDMA IS95.
(3) TD-SCDMA
Full-called Time Division - Synchronous CDMA (Time Division Synchronous CDMA), by the standards of the Chinese mainland's development of its own 3G standard, June 29, 1999, China's former Ministry of Posts and Telecommunications Academy of Telecommunications Technology (Datang Telecom) made to the ITU. The intelligent wireless standard, synchronous CDMA radio and software, and so today the world's leading technology into one, in the spectrum utilization, and support for business flexibility, frequency and flexibility in areas such as the cost of the unique advantages. In addition, because of the huge domestic market, which is subject to major telecommunications equipment manufacturers attention, more than half of the global equipment manufacturers have announced to support TD-SCDMA standard. The proposed standard without going through the middle of the 2.5-generation link directly to the transition to 3G, is applicable to the GSM system upgrade to 3G.
(4) WiMAX
WiMAX is the full name of the Worldwide Interoperability for Microwave Access (Worldwide Interoperability for Microwave Access), also known as the 802.16 wireless MAN, is also a corporate and home users to provide "last mile" broadband wireless connection program. This technology and the need to avoid authority or authorized by the combination of microwave equipment, due to lower-cost, wireless broadband market will expand and improve the enterprises and service providers awareness. October 19, 2007, the International Telecommunication Union in Geneva at the plenary meeting of wireless communications, after most countries vote, WiMAX was approved to become official following the WCDMA, CDMA2000 and TD-SCDMA after the fourth of global 3G standards.
Monday, October 13, 2008
GPRS and GPS
They do not belong to one area of technology, but we can not in the same breath.
According to reports, GPS for "global positioning system", a location technology to recognize objects of latitude and longitude position, at least 10 years there will not be more advanced than the GPS positioning technology. The GPRS is intended to "General Packet Radio Service data" is just a data transfer method used to transfer data group, as mobile phones to send text messages, do not have any position or function of anti-theft robbery. GPRS is a GPS component, for the application of GPS technology played a data transmission. If the GPS leader, "St. SEG car", there are several ways to use GPRS data transmission.
According to reports, GPS for "global positioning system", a location technology to recognize objects of latitude and longitude position, at least 10 years there will not be more advanced than the GPS positioning technology. The GPRS is intended to "General Packet Radio Service data" is just a data transfer method used to transfer data group, as mobile phones to send text messages, do not have any position or function of anti-theft robbery. GPRS is a GPS component, for the application of GPS technology played a data transmission. If the GPS leader, "St. SEG car", there are several ways to use GPRS data transmission.
GPRS technology
1.GPRS technology embodied
General Packet Radio Service GPRS, GSM-based system is a wireless packet switching technology, to provide end-to-end, wide-area wireless IP connection. Tongsudejiang, GPRS is a high-speed data-processing technology, methods of "division" in the form of transmitting information to the hands of the user. Although GPRS is available as a GSM network to the 3G mobile communications technology evolution of the transition, but in many ways, has a significant advantage. At present, Hong Kong's status as the first testing ground for GPRS areas, have achieved good results.
Due to the use of a "group" of technology, Internet users can be disconnected from the suffering of the (situation about the use of just a software download NetAnts almost). In addition, the use of GPRS and WAP access to the Internet and in different ways, such as WAP access on the Internet at home, the first "dial-up connection" and then the Internet can not use the telephone line, but on more favorable GPRS, download information and can call At the same time. Technically, the transmission of voice (that call) to continue to use GSM, and data can be transmitted using GPRS, this is the case, put mobile phone applications to a higher level. GPRS technology development and also the "economy", because only the existing GSM network to develop. GPRS uses the wide range of issues, including the adoption of mobile phones to send and receive e-mail, browse the Internet, and so on.
Internet phones are now the slogan is "always online", "IP in hand", using GPRS, the realization of the data packet to send and receive, at the same time this means that the user is always online and by billing traffic, to quickly lower the costs of the services. The continued state of dystocia in China Mobile / Unicom WAP tariff policy, if the CSD (circuit-switched data, that is usually said that the dial-up data, WAP European and Asian business methods used by the bearer) carrying changed to achieve the GPRS, it means that Dozens of people from a common commitment to one of the original cost.
And GPRS the greatest advantage: its data transfer speed is not WAP can be compared. The current GSM mobile communications network for the transmission speed of 9.6K bytes per second, GPRS mobile phones launched in the beginning of this year have reached a speed of 56Kbps, up to now is to achieve a 115Kbps (this is the speed of common ideals 56Kmodem twice the rate) . Therefore, we cherish you in the hands of Nokia7110 and MotorolaL2000, I believe that the introduction of GPRS handsets, they have to give way.
2. Packet (Packet) technology
The so-called packet (Packet) is the Date package into a number of separate packets, and then these packets to send out one by one, a bit similar in form to send parcels, the advantages of using packet-switched only when there is a need to send information when Will take up bandwidth, but also to transfer the amount of data pricing, which the user is a more reasonable way of accounting, because the Internet such as data transmission bandwidth is most of the time between the home. In addition, GSM phase 2, the standard, GPRS offers four different coding methods, the encoding also provide different protection error (Error Protection) capability. The use of four different encoding every time slot available for transfer rate of CS-1 (9.05K), CS-2 (13.4K), CS-3 (15.6K) and CS-4 (21.4K), which CS-1 to protect the most rigorous, CS-4, it is absolutely not be any protection. At the same time, each user can use a maximum of eight hours slot, so-called GPRS for a maximum transfer rate of 171.2K.
3.GPRS network structure
GPRS network is based on the existing GSM network to achieve. In the existing GSM networks need to increase the number of nodes, such as GGSN (Gateway GPRSSupporting Node, Gateway GPRS support node) and SGSN (Serving GSN, to support the GPRS service node).
GPRS network reference model as shown in Figure 1. GSN is the GPRS network, the most important nodes of the network. GSN with a mobile routing management functions, which can connect various types of data networks and can be connected to the GPRS register. GSN to be completed and a variety of mobile data network between the data and format conversion. GSN can be a similar independent of routers and prepared, in the GSM and can also be integrated with the MSC.
GSN There are two types: one for the SGSN (Serving GSN, services GSN), the other for the GGSN (GatewayGSN, Gateway GSN), SGSN main role is to record the mobile station from its current location information and mobile station and GGSN Between the completion of the mobile division to send and receive data. GGSN is the main gateway from the role it can be a wide range of data and network connections such as ISDN, PSPDN and LAN, and so on. Some of the literature, the GGSN called GPRS router. GGSN can GSM network in the GPRS packet data protocol conversion package that will allow these groups to send packets to the remote TCP / IP or X.25 network.
In addition, some manufacturers raised GR (GSMRegister, GPRS data) concept. GR similar to the GSM in the HLR, is a GPRS business database. It can stand on its own, and can co-exist HLR by the server or the realization of program-controlled switches. GR in the name of the ETSI's proposal does not specifically mentioned.
GPRS network also introduced a new network interface of the following:
Gn, GSN backbone interface for a variety of between GSN
Gb, BSS and the interface between the sGsN.
Gr, SGSN and the interface between the HLR.
Gp, different GSM networks (different PLMN) interface between.
Gs, SGSN and the interface between the MSC.
4.GPRS agreement model
Um is the interface of the GSM air interface. Um interface communication protocol layer 5, bottom-up followed by the physical layer, MAC Mdium AccessControl) layer, LLC (Logical Link Control) layer, SNDC (Subnetwork DependantConvergence) layer and network layer.
Um interface of the physical layer for the radio frequency interface, and the physical link layer is responsible for providing a variety of air interface logical channel. GSM air interface to the carrier frequency bandwidth 20OkHz, a carrier frequency is divided into 8 physical channels.
8 If you have physical distribution channel for the transmission of GPRS data, the raw data rate of up to 20Okb / s. Forward Error Correction Code to consider the costs, the final data rate of up to 164kb / s or so.
MAC for media access control layer. MAC's main role is to define the distribution of air interface and the GPRS logical channel, so that these channels will be different mobile sharing. GPRS logical channel of a total of 3 categories, namely, the Public Channel, channel and business groups GPRS radio channel. Public Channel used to transmit data communications control signaling, is subdivided into specific responses, such as paging and channel. Business groups to channel packet data transmission. Radio channel is used to the mobile network to send information.
LLC Logical Link Control layer to layer. It is a high-speed data link based on the order of the HDLC protocol wireless link. LLC layer is responsible for the high-level SNDC layer SNDC data unit formed LLC address field frame in order to generate full-frame LLC. In addition, LLC can be a point-to-multipoint addressing the frame and the re-issued control.
LLR in the BSS layer is a logical link layer transmission. This layer is responsible for MS and SGSN transfer between the frame LLC. LLR layer SNDC for the data unit is transparent, that is not responsible for SNDC data.
SNDC known as the combination dependence on sub-layer. Its main role is to complete the transfer of data packet, packing, determine the TCP / IP address and encryption methods. SNDC in the layer, mobile and data transmission between the SGSN has been divided into one or more packets SNDC unit. SNDC packet generation unit was placed intra LLC.
Network layer protocol of the current stage of Phase 1 is provided by the TCP / IP protocol and L25. TCP / IP and X.25 protocol to the traditional GSM network equipment (such as equipment such as the NSS and BSS) is transparent.
5.GPRS routing management
GPRS is the management of the routing GPRS networks and addressing how to set up a data transmission route. GPRS routing management in the following 3 areas: mobile station to send data to establish the route; mobile station set up to receive data routing; and mobile roaming at the time of the establishment of routing data.
In the first case, in Figure 3 shown in a path. When the mobile station have had a PDU (packet data unit), the PDU after SNDC layer processing, called SNDC data unit. LLC layer and then, after dealing with LLC for CHENG through the air interface to the GSM mobile network in Taiwan's SGSN. SGSN the data sent to the GGSN. GGSN to receive the news of solutions for dealing with equipment, can be converted into a public data transmission network in the format (such as PSPDN the PDU), a public data network to the end user. In order to improve the efficiency of the transmission, data transmission and to ensure the safety of air interface can be done on data compression and encryption.
In the second case, a public data network users send data to mobile station. First of all, the data network through the establishment of a standard agreement between the GGSN and data network routing. Data issued by the network user data unit (for example, PSPDN in the PDU), through the establishment of good data routing unit PDU to GGSN. GGSN and then to the PDU mobile station where the SGSN on GSN into the PDU package SNDC data unit, another layer to deal with LLC to LLC unit frame and eventually through the air interface to the mobile station.
The third is a data network to transmit data to a user is roaming of mobile users. The data must go through attribution to the GGSN, and then sent to the mobile user A. In the air by the mouth of the channel constitutes a GPRS air interface channel as follows:
PDTCH (Pachet Data Traffic Channe1), packet data channel. This channel used to send the air interface GPRS packet data.
PPCH (Packet Paging Channe1), group paging channel for paging PPCH called GPRS users.
PRACH (Packet Randem Access Channel), grouping random access channel. GPRS users PRACH to the base station to issue a request channel.
PAGCH (Packet Access Grant Channel), Packet Access response channel. PAGCH is a response channel, the response to PRACH.
PACCH (Packet Asscrchted ControlChannel), with the sub-Channel routes. This channel used to send the realization of GPRS data services signaling.
6. GPRS technology services
GPRS packet data billing functions, that is, according to billing data.
7. GPRS and IP
The introduction of GPRS technology, telecommunications networks and computer networks, organically linked to North Korea in the future all-IP network platform for development.
GPRS can be seen from the structure, the base station and the connection between the SGSN prepared through the general frame relay connection, SGSN and GGSN equipment between the IP network.
GGSN may be replaced by an NAT (network address translation) routers to assume the function of internal and external IP address of the IP network address translation, MS may be accessed within the GPRS network can also be APN (external network access by name) to visit the external PDN / Internet network.
Logo in the GPRS devices such as mobile phones MS logo in addition to the GSM used in the IMSI, MSISDN number, and so on, but also need the distribution of IP addresses. Network element equipment SGSN, GGSN logo of the existing SS7 address, and the IP address of the GGSN data, GSN (SGSN or GGSN) communications between the use of IP addresses, and GSN with the MSC, HLR, and other entities use of communication 7 Signaling its address. GPRS in the system, there are two important records database information. First, the user mobility management context for the management of the mobile user location information, and the other is the user context of the PDP (Packet Data context of the agreement) for the management of MS from the phone to Gateway GGSN and the ISP (Internet Service Provider ) Between the data routing information. When MS access GPRS network internal or external PDN / Internet network, MS to activate PDP fat SGSN context of a request message, MS may choose to contract with the operator of fixed service GGSN. According to the rules of APN or choose from SGSN choice GGSN, SGSN made GGSN to the establishment of information PDP context request. GGSN allocated an IP address of the MS (static or dynamic, public or private), set up in the context of the PDP, the need for the user's identity, the need for quality of service for authentication and verification in the successful establishment and activation after the PDP context, MS , SGSN and GGSN are stored PDP context of the user's information. With the user's location information and data routing information, MS will be able to access the network resources. Second-generation GPRS and a half of the products available in the development and deployment of GPRS business encountered some new concepts.
GPRS application
1.GPRS of WAP application
WAP and GPRS is a combination of current orders, "Internet phone" to a new level of the best implementation of the program: GPRS is a powerful underlying transport, WAP is a high-level applications, if the WAP as a speeding vehicle, then GPRS is wide open for high-speed Road, you any information in the wireless world of surf at random.
2. Equipment
In addition to the GPRS cellular phone can be a variety of devices other than the reality, including the laptop computer PCMCIA modem, personal digital assistants and the extension of the hand-held computer. At present, the popular E-mail portable device BlackBerry (BlackBerry) manufacturer Research in Motion (RIM) in a Microcell Telecommunications known as the GSM providers to study how the other for GPRS wireless system to send messages.
3.GPRS business applications
Since the first text messaging, wireless data applications has gone through a leap of growth, just look at the well-known European and American manufacturers publicized General Packet Radio Service (GPRS) of thrust seems to be able to feel the next generation of mobile Data applications will be the advent of the era. 99 will be the end or early in 2000 to open the General Packet Radio Service GPRS, into a third-generation personal multimedia services an important milestone will enable mobile communications and data networks together so that the IP business to the introduction of a broad mobile market . Although the use of mobile data is a relatively small, but in some markets, the different user groups are being developed rapidly, its main driving force in the area of mobile data services used in the commercial market. Whether Ericsson, Nokia or Alcatel, almost all of the publicity GPRS manufacturers are business users of the fast-growing market to persuade the operator.
GSM system for mobile data communications division (that is, GPRS) is the basic packet radio service, using packet switching the way, the data rate of up to 164kb /, it can be to provide GSM mobile environment, high-speed data business, but also Transceiver to provide Emai1, Internet access features such cases.
4.GPRS function of the corresponding business applications
GPRS is a new GSM data services, which can give mobile users with wireless data packet access Services Unit. GPRS is a remote and mobile users in the data network (such as support for the TCP / IP, X.25 network, and so on) to provide a connection between so as to provide users with high-speed mobile wireless IP and wireless business X.25.
Using GPRS packet switching technology, which allows multiple users to share some of the fixed channel resources. If the air interface on the TDMA frame of 8 slots are used to transmit data, the data rate of up to 164kb/8.GSM air interface channel resources can be occupied by voice, GPRS data services can be occupied. Of course, in the channel adequate conditions, can channel some of the definition of GPRS dedicated channel.
To achieve the GPRS network, the need for the traditional GSM network, the introduction of a new network interface and communication protocols. At present, the introduction of GPRS network GSN (GPRS SurportingNode) node. Taiwan Mobile will be GPRS mobile station or GPRS / GSM dual-mode mobile station.
WAP and GPRS is a combination of current orders, "Internet phone" to a new level of the best implementation of the program: GPRS is a powerful underlying transport, WAP is a high-level applications, if the WAP as a speeding vehicle, then GPRS is wide open for high-speed Road, you any information in the wireless world of surf at random.
2. Equipment
In addition to the GPRS cellular phone can be a variety of devices other than the reality, including the laptop computer PCMCIA modem, personal digital assistants and the extension of the hand-held computer. At present, the popular E-mail portable device BlackBerry (BlackBerry) manufacturer Research in Motion (RIM) in a Microcell Telecommunications known as the GSM providers to study how the other for GPRS wireless system to send messages.
3.GPRS business applications
Since the first text messaging, wireless data applications has gone through a leap of growth, just look at the well-known European and American manufacturers publicized General Packet Radio Service (GPRS) of thrust seems to be able to feel the next generation of mobile Data applications will be the advent of the era. 99 will be the end or early in 2000 to open the General Packet Radio Service GPRS, into a third-generation personal multimedia services an important milestone will enable mobile communications and data networks together so that the IP business to the introduction of a broad mobile market . Although the use of mobile data is a relatively small, but in some markets, the different user groups are being developed rapidly, its main driving force in the area of mobile data services used in the commercial market. Whether Ericsson, Nokia or Alcatel, almost all of the publicity GPRS manufacturers are business users of the fast-growing market to persuade the operator.
GSM system for mobile data communications division (that is, GPRS) is the basic packet radio service, using packet switching the way, the data rate of up to 164kb /, it can be to provide GSM mobile environment, high-speed data business, but also Transceiver to provide Emai1, Internet access features such cases.
4.GPRS function of the corresponding business applications
GPRS is a new GSM data services, which can give mobile users with wireless data packet access Services Unit. GPRS is a remote and mobile users in the data network (such as support for the TCP / IP, X.25 network, and so on) to provide a connection between so as to provide users with high-speed mobile wireless IP and wireless business X.25.
Using GPRS packet switching technology, which allows multiple users to share some of the fixed channel resources. If the air interface on the TDMA frame of 8 slots are used to transmit data, the data rate of up to 164kb/8.GSM air interface channel resources can be occupied by voice, GPRS data services can be occupied. Of course, in the channel adequate conditions, can channel some of the definition of GPRS dedicated channel.
To achieve the GPRS network, the need for the traditional GSM network, the introduction of a new network interface and communication protocols. At present, the introduction of GPRS network GSN (GPRS SurportingNode) node. Taiwan Mobile will be GPRS mobile station or GPRS / GSM dual-mode mobile station.
The development of GPRS
According to the European ETSI's first GSM Phase 2 +, GPRS is divided into two stages of development (that is, Phase 1 and Phase2). GPRS stage of the Phase l will be able to function and support the following:
1.TCP/IP business and X.25
2.'s New GPRS air interface encryption technology
Additional business 3.GPRS
4. Enhanced SMS (E-SMs)
GPRS packet data billing functions, that is, based on the amount of data taken by the above-mentioned functions of billing operations of the most significant is the TCP / IP and X.25 functions. GSM network via TCP / IP and X.25 to provide users with e-mail, WWW browser, a dedicated data, LAN access and other services. GPRS Phase 2 stage of the norms are still being worked out, it will be able to provide more new features and new business.
1.TCP/IP business and X.25
2.'s New GPRS air interface encryption technology
Additional business 3.GPRS
4. Enhanced SMS (E-SMs)
GPRS packet data billing functions, that is, based on the amount of data taken by the above-mentioned functions of billing operations of the most significant is the TCP / IP and X.25 functions. GSM network via TCP / IP and X.25 to provide users with e-mail, WWW browser, a dedicated data, LAN access and other services. GPRS Phase 2 stage of the norms are still being worked out, it will be able to provide more new features and new business.
GPRS features
1. Application on the characteristics of
At present, the Internet using a mobile phone is also a bit less than satisfactory. As a result, a comprehensive solution GPRS so it came into being, this new technology can make you at any time, any place can be quickly and easily connect at the same time very reasonable cost. In short: speed up, and rich in content, applications increased, while the costs are more reasonable.
(1) high-speed data transmission
10 times the speed of GSM, but also fulfill the needs of your ideals, but also to stability in the transmission of high-capacity, high-quality audio and video files, is generally not great progress.
(2) always-on
Since the establishment of a new connection without almost any time (that is, no need for each visit to the establishment of the data call connection), so any time you can keep in touch and network, for example, in the absence of support for GPRS, is when you surf the net, and At this point there is just phone access, most of the time you have to get disconnected after the call, the call after the re-dial-up. For most people, this really is very irritating. And with GPRS, you can easily resolve this conflict.
(3) only by the flow of data billing
That is, based on the amount of data you transfer (such as: downloading information) to billing, rather than time online billing is to say, not as long as data transmission, even if you have been "online", and need not pay. To be a "call" for instance, the use of GSM WAP mobile Internet access, like telephone billing began to get through; use GPRS WAP Internet access will be much more reasonable, just as telephone access charges is not only dialogue When calculating the cost. In short, it truly reflects the use of low pay.
2. Technical characteristics
Data sent to realize and accept the subsector, according to the billing flow; 56 ~ 115Kbps transmission speed.
Due to the use of a "group" of technology, Internet users can be disconnected from the suffering of the (situation about the use of just a software download NetAnts almost). In addition, the use of GPRS and WAP access to the Internet and in different ways, such as WAP access on the Internet at home, the first "dial-up connection" and then the Internet can not use the telephone line, but on more favorable GPRS, download information and can call At the same time. Technically, the transmission of voice (that call) to continue to use GSM, and data can be transmitted using GPRS, this is the case, put mobile phone applications to a higher level. GPRS technology development and also the "economy", because only the existing GSM network to develop. GPRS uses the wide range of issues, including the adoption of mobile phones to send and receive e-mail, browse the Internet, and so on.
Internet phones are now the slogan is "always online", "IP in hand", using GPRS, the realization of the data packet to send and receive, at the same time this means that the user is always online and by billing traffic, to quickly lower the costs of the services. The continued state of dystocia in China Mobile / Unicom WAP tariff policy, if the CSD (circuit-switched data, that is usually said that the dial-up data, WAP European and Asian business methods used by the bearer) carrying changed to achieve the GPRS, it means that Dozens of people from a common commitment to one of the original cost.
GPRS greatest advantage is its data transfer speed is not WAP can be compared. The current GSM mobile communications network for the transmission speed of 9.6kbps, GPRS mobile phones launched in the beginning of this year have reached a speed of 56Kbps, up to now is to achieve a 115Kbps (this is the speed of common ideals 56Kmodem twice the rate).
GPRS is packet-switched data transmission manner, is due to packet switching, so the utilization of network resources than circuit-switched has been greatly improved, but at the same time GPRS voice and data transmission and billing Can be produced in accordance with the traffic statistics. The existing WAP is the bearer of the circuit-switched (CSD) way, way circuit-switched voice and data can not be carried out at the same time, in accordance with the charging system is also a long time to charge.
In fact its own WAP and GPRS are not comparable in nature, the existing WAP content in the above GPRS can browse and application of GPRS is only available means of CSD's WAP faster, more convenient and more reasonable charges, WAP services on the network also due to technological advances and greater promotion and improvement.
In the long run, WAP are using CSD (circuit-switched data), GSM data services, after the WAP can also use GPRS to the new GSM network as a way of carrying.
Therefore, GPRS will not replace the WAP, to cite an example of the image: GPRS and CSD is the way the GSM data services are the road, WAP is a road car, WAP is now running in lane two, GPRS enhanced data transfer speed , Is the 8-lane, it can be said GPRS enhanced WAP services, available on WAP content can browse through GPRS and applications.
GPRS application, but also later with Bluetooth (Bluetooth). At that time, plus a digital camera bluetooth, can be immediately adopted by the phone to send photos to distant places, but a quarter of an hour's time, let cool, this time we will be away from far away.
3.GPRS compared with the GSM show the characteristics of
Compared to the GSM terms of the speed of 9.6kbps visit, GPRS speeds have 171.2kbps visit; in the establishment of connection time, GSM needed 10-30 seconds, and GPRS only a very short period of time can be related to the visit request; for Terms of cost, GSM is connected by the time of billing, and the only GPRS data traffic according to billing; GPRS network resources utilization and relatively much higher than the GSM.
4.GPRS correspond to the characteristics of the scope of services
1. M-Commerce
2. Mobile Information Service
3. Mobile Internet
4. Multimedia services
The technical 5.GPRS advantage
(1) relatively low-cost connectivity
High resource utilization in the GSM network, GPRS introduction of the first packet-switched transmission mode, making use of the original model of the circuit-switched GSM data transmission means there has been a fundamental change in wireless scarce resources under the circumstances it is particularly important. According to circuit-switched mode, to connect the entire period, regardless of whether users will send data occupies its own wireless channel. In conversation, many applications are often a lot of free time, as Internet browsing, send and receive E-mail and so on. The packet switching mode, the user only send or receive data only during the occupation of resources, which means that multiple users can efficiently share the same wireless channel, resulting in improved resource utilization. GPRS user billing to the amount of data communications as the main basis for the concept of "how much, how much to pay" principle. In fact, GPRS users to connect up to a few hours time, but pay relatively low-cost connections.
(2) a high transfer rate
GPRS will provide up to 115kbit / s transfer rate (the highest value for 171.2kbit / s, not including FEC). This means that in a few years, portable computers, GPRS, and ISDN users the same user to quickly browse the Internet, as well as some of the transmission rate-sensitive mobile multimedia applications possible.
(3) access packet-switched access time is short time for less than 1GPRS is a new GSM data services, which can give mobile users with wireless data packet access Services Unit. GPRS is a remote and mobile users in the data network (such as support for the TCP / IP, X.25 network, and so on) to provide a connection between so as to provide users with high-speed mobile wireless IP and wireless business X.25.
Using GPRS packet switching technology, which allows multiple users to share some of the fixed channel resources. If the air interface on the TDMA frame of 8 slots are used to transmit data, the data rate of up to 164kb/8.GSM air interface channel resources can be occupied by voice, GPRS data services can be occupied. Of course, in the channel adequate conditions, the number of channels can be defined as GPRS dedicated channel. To achieve the GPRS network, the need for the traditional GSM network, the introduction of a new network interface and communication protocols. At present, the introduction of GPRS network GSN (GPRS Surporting Node) node. Taiwan Mobile will be GPRS mobile station or GPRS / GSM dual-mode mobile station.
At present, the Internet using a mobile phone is also a bit less than satisfactory. As a result, a comprehensive solution GPRS so it came into being, this new technology can make you at any time, any place can be quickly and easily connect at the same time very reasonable cost. In short: speed up, and rich in content, applications increased, while the costs are more reasonable.
(1) high-speed data transmission
10 times the speed of GSM, but also fulfill the needs of your ideals, but also to stability in the transmission of high-capacity, high-quality audio and video files, is generally not great progress.
(2) always-on
Since the establishment of a new connection without almost any time (that is, no need for each visit to the establishment of the data call connection), so any time you can keep in touch and network, for example, in the absence of support for GPRS, is when you surf the net, and At this point there is just phone access, most of the time you have to get disconnected after the call, the call after the re-dial-up. For most people, this really is very irritating. And with GPRS, you can easily resolve this conflict.
(3) only by the flow of data billing
That is, based on the amount of data you transfer (such as: downloading information) to billing, rather than time online billing is to say, not as long as data transmission, even if you have been "online", and need not pay. To be a "call" for instance, the use of GSM WAP mobile Internet access, like telephone billing began to get through; use GPRS WAP Internet access will be much more reasonable, just as telephone access charges is not only dialogue When calculating the cost. In short, it truly reflects the use of low pay.
2. Technical characteristics
Data sent to realize and accept the subsector, according to the billing flow; 56 ~ 115Kbps transmission speed.
Due to the use of a "group" of technology, Internet users can be disconnected from the suffering of the (situation about the use of just a software download NetAnts almost). In addition, the use of GPRS and WAP access to the Internet and in different ways, such as WAP access on the Internet at home, the first "dial-up connection" and then the Internet can not use the telephone line, but on more favorable GPRS, download information and can call At the same time. Technically, the transmission of voice (that call) to continue to use GSM, and data can be transmitted using GPRS, this is the case, put mobile phone applications to a higher level. GPRS technology development and also the "economy", because only the existing GSM network to develop. GPRS uses the wide range of issues, including the adoption of mobile phones to send and receive e-mail, browse the Internet, and so on.
Internet phones are now the slogan is "always online", "IP in hand", using GPRS, the realization of the data packet to send and receive, at the same time this means that the user is always online and by billing traffic, to quickly lower the costs of the services. The continued state of dystocia in China Mobile / Unicom WAP tariff policy, if the CSD (circuit-switched data, that is usually said that the dial-up data, WAP European and Asian business methods used by the bearer) carrying changed to achieve the GPRS, it means that Dozens of people from a common commitment to one of the original cost.
GPRS greatest advantage is its data transfer speed is not WAP can be compared. The current GSM mobile communications network for the transmission speed of 9.6kbps, GPRS mobile phones launched in the beginning of this year have reached a speed of 56Kbps, up to now is to achieve a 115Kbps (this is the speed of common ideals 56Kmodem twice the rate).
GPRS is packet-switched data transmission manner, is due to packet switching, so the utilization of network resources than circuit-switched has been greatly improved, but at the same time GPRS voice and data transmission and billing Can be produced in accordance with the traffic statistics. The existing WAP is the bearer of the circuit-switched (CSD) way, way circuit-switched voice and data can not be carried out at the same time, in accordance with the charging system is also a long time to charge.
In fact its own WAP and GPRS are not comparable in nature, the existing WAP content in the above GPRS can browse and application of GPRS is only available means of CSD's WAP faster, more convenient and more reasonable charges, WAP services on the network also due to technological advances and greater promotion and improvement.
In the long run, WAP are using CSD (circuit-switched data), GSM data services, after the WAP can also use GPRS to the new GSM network as a way of carrying.
Therefore, GPRS will not replace the WAP, to cite an example of the image: GPRS and CSD is the way the GSM data services are the road, WAP is a road car, WAP is now running in lane two, GPRS enhanced data transfer speed , Is the 8-lane, it can be said GPRS enhanced WAP services, available on WAP content can browse through GPRS and applications.
GPRS application, but also later with Bluetooth (Bluetooth). At that time, plus a digital camera bluetooth, can be immediately adopted by the phone to send photos to distant places, but a quarter of an hour's time, let cool, this time we will be away from far away.
3.GPRS compared with the GSM show the characteristics of
Compared to the GSM terms of the speed of 9.6kbps visit, GPRS speeds have 171.2kbps visit; in the establishment of connection time, GSM needed 10-30 seconds, and GPRS only a very short period of time can be related to the visit request; for Terms of cost, GSM is connected by the time of billing, and the only GPRS data traffic according to billing; GPRS network resources utilization and relatively much higher than the GSM.
4.GPRS correspond to the characteristics of the scope of services
1. M-Commerce
2. Mobile Information Service
3. Mobile Internet
4. Multimedia services
The technical 5.GPRS advantage
(1) relatively low-cost connectivity
High resource utilization in the GSM network, GPRS introduction of the first packet-switched transmission mode, making use of the original model of the circuit-switched GSM data transmission means there has been a fundamental change in wireless scarce resources under the circumstances it is particularly important. According to circuit-switched mode, to connect the entire period, regardless of whether users will send data occupies its own wireless channel. In conversation, many applications are often a lot of free time, as Internet browsing, send and receive E-mail and so on. The packet switching mode, the user only send or receive data only during the occupation of resources, which means that multiple users can efficiently share the same wireless channel, resulting in improved resource utilization. GPRS user billing to the amount of data communications as the main basis for the concept of "how much, how much to pay" principle. In fact, GPRS users to connect up to a few hours time, but pay relatively low-cost connections.
(2) a high transfer rate
GPRS will provide up to 115kbit / s transfer rate (the highest value for 171.2kbit / s, not including FEC). This means that in a few years, portable computers, GPRS, and ISDN users the same user to quickly browse the Internet, as well as some of the transmission rate-sensitive mobile multimedia applications possible.
(3) access packet-switched access time is short time for less than 1GPRS is a new GSM data services, which can give mobile users with wireless data packet access Services Unit. GPRS is a remote and mobile users in the data network (such as support for the TCP / IP, X.25 network, and so on) to provide a connection between so as to provide users with high-speed mobile wireless IP and wireless business X.25.
Using GPRS packet switching technology, which allows multiple users to share some of the fixed channel resources. If the air interface on the TDMA frame of 8 slots are used to transmit data, the data rate of up to 164kb/8.GSM air interface channel resources can be occupied by voice, GPRS data services can be occupied. Of course, in the channel adequate conditions, the number of channels can be defined as GPRS dedicated channel. To achieve the GPRS network, the need for the traditional GSM network, the introduction of a new network interface and communication protocols. At present, the introduction of GPRS network GSN (GPRS Surporting Node) node. Taiwan Mobile will be GPRS mobile station or GPRS / GSM dual-mode mobile station.
GPRS Overview
GPRS is General Packet Radio Service (General Packet Radio Service) abbreviation, it can only be broken through the GSM network to provide circuit-switched way of thinking, only by increasing the functionality of the existing entities and the base part of the system to achieve reform Packet switching, the transformation of inputs is not relatively large, but the user data rate is quite impressive. GPRS (General Packet Radio Service) is a global system of mobile (GSM)-based data transfer technology, is an extension of GSM. GPRS and in the past in a row in the channel of transmission in different ways, based on packet (Packet)-transmission to, so users have to pay the costs of its transmission is calculated on the basis of the information, not to use their channels as a whole, in theory, cheaper.
GPRS transmission rate can be raised to 56 or even 114Kbps. Moreover, no longer needed because the existing wireless applications intermediaries need converter, the connection will be more convenient and easier to transport. However, users can access on-line, participate in the dissemination of interactive video conferencing and video on the same network (VRN) user, even without the need for dial-up, and continued with the network connection.
GPRS transmission rate can be raised to 56 or even 114Kbps. Moreover, no longer needed because the existing wireless applications intermediaries need converter, the connection will be more convenient and easier to transport. However, users can access on-line, participate in the dissemination of interactive video conferencing and video on the same network (VRN) user, even without the need for dial-up, and continued with the network connection.
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