HSPA + technology
HSPA + (HSPA plus) or HSPA Evolution (HSPA improved) is the next generation of HSPA launched by 3GPP after R6 (HSUPA technology). HSPA + is considered 3.5G technology. This means that HSPA + will be backward compatible with HSPA. Therefore, Telco has HSPA infrastructure available, upgrading to HSPA + will be very easy, cost-effective (due to the availability of existing stations), the speed is quite high.
Figure 3 : HSPA + is capable of serving all IP services *: Multicasting is a one-to-many way of transferring data.This is an effective way to transmit text, audio, and video to a group of people online.
HSPA + R7 is currently commercialized earlier this year, and HSPA + R8 will be officially launched next year. The highlight of this technology compared to HSPA is the use of 2x2 MIMO (Multiple Input Multiple Output) technology with 2 transmitting antennas and 2 receiving antennas, using 16QAM modulation method (HSPA using QPSK) for uplink and 64QAM ( instead of 16QAM as HSPA) for downlink, it is much faster than HSPA. HSPA + R7 has 28Mbps downlink speed (twice as high as HSPA and more than double that of WCDMA), 11Mbps uplink; HSPA + R8 has downlink speeds of up to 42Mbps and 11Mbps uplink. In the future, HSPA + R9 may have uplink speeds of up to 84Mbps and uplink up to 23Mbps or higher.(See pictures 2 and 3)
GPRS and EDGE
GPRS (General Package Radio Service - general packet radio service) is a value-added service of GSM network. GPRS uses packet switching technology to access external data networks (such as LAN, Internet .) using IP (Internet Protocol) protocol with high speed. This is considered generation network technology 2.5 (2.5G) - a step forward from GSM to 3G. The traditional data service of GSM network only has a maximum speed of 9.6Kbps, while GPRS R98 and R99 have a maximum speed of up to 171.2Kbps (theoretically), nearly 20 times higher than Data service of GSM network. According to R97, GPRS has a speed of 40Kbps (downlink) and 14Kbps (uplink). With this relatively high speed, GSM network subscribers can access additional value-added services such as WAP, MMS (Multimedia Messaging Service - multimedia messaging service), web browsing, video watching, music listening . GPRS allows 8 subscribers to use a radio channel and a subscriber can use 8 radio channels simultaneously. This technology uses modulation method for GMSK.
EDGE (Enhanced Data GSM Environment) is a technology that speeds up data transmission in GSM networks. EDGE is not a 3G network but it is only at 2.75G. EDGE, sometimes called EGPRS, is an upgraded GPRS technology that allows data transfer at speeds of up to 384Kbps for fixed or slow-moving users and 144Kbps for high-speed users. . According to R98, EDGE has a downlink rate of 1.3Mbps and uplink of 653Kbps. This technology is the premise for mobile information service providers when switching to 3G using HSPA technology - a GSM transition of 2.5G to 3G. During the transition period when switching to 3G, Telco has applied EDGE technology to enhance the transmission speed for its value-added services.
EDGE is also a value-added service of GSM networks but has higher speeds, lower latency than GPRS. EDGE supports EGPRS (Enhanced General Packet Radio Service) packet switching and ESCD (Enhanced Circuit Switched Data) circuit switching. With a high data transfer rate, EDGE allows providers to deploy advanced mobile services such as downloading videos, music clips, multimedia messages, Internet access, email . EDGE using methods New modulation, coding and transmission mechanism to achieve maximum data transfer rate (3 times the maximum speed of GPRS). While GPRS uses GMSK modulation, EDGE uses an additional 8-PSK modulation. Therefore, to implement EDGE, mobile information service providers also need to prepare appropriate upgrade / replacement solutions.
CDMA20001xEVDO for CDMA network
Originally, 1xEV-DO was an acronym for ' 1x Evolution-Data Only ' (1x Improvements - Data-exclusive). After that, because the negative meaning can be given when the market of the word ' Only ' is introduced, the ' DO ' part in the name 1xEV-DO has been changed to 'Data Optimized'. Therefore, 1xEV-DO stands for '1x Evolution-Data Optimized' (1x Improvements - Data Optimization), to make a better impression of the ability to optimize data transfer when marketed. This is the standard for wireless broadband data transmission for wireless devices, allowing speeds up to 2.4Mbps (downlink) on CDMA networks (Code Division Multiple Access - multiple accesses divided by code). This technology is standardized by the 3GPP2 agreement as part of the CDMA2000 set of standards. The main objective of CDMA20001xEV-DO is to allow users to implement high-speed applications, 2-way interactions (downlink and uplink) in real time such as sending / receiving emails, photos, videos, and music content. great…
WCDMA
WCDMA followers claim that CDMA technology outperforms GSM technology. CDMA is 3G technology. To go to 3G, GSM also has to rely on CDMA (exactly Wideband Code Division Multiple Access (WCDMA) - Multi-access technology divided by broadband code. In spread spectrum engineering, instead of using GSM or FDMA or TDMA methods, WCDMA uses DS-CDMA (Direct Spread CDMA) direct spread method to get higher speed and support more users than 2G network. .
The advantage of this technology is to support many different speed levels: 144Kbps when moving fast, 384Kbps when walking (outdoor) and the highest is 2Mbps when not moving (indoors). With high speed, WCDMA is capable of supporting broadband services such as high-speed Internet access, watching movies, listening to music at the same level as the wired connection. WCDMA is in the 1920MHz -1980MHz range, 2110MHz - 2170MHz . This technology is currently being deployed on GSM networks available in the US and some other regions.
1x technology mainly uses CDM algorithm (Code Division Multiplexing) while EV-DO uses TDM technology (Time Division Multiplexing). When deployed with an existing mobile network, CDMA20001xEV-DO requires a separate 1.25MHz bandwidth. Note that CDMA20001xEV-DO has many versions. In particular, CDMA20001xEV-DO Rev.A (data and voice), which was developed from the first version CDMA20001xEV-DO Rev.0 (data only), has been implemented in Japan and South Korea. Rev.A shows how to set up high-speed packet data transfer in both up and down directions. Rev.B is improved by combining multiple 1.25MHz channels on Rev. A speed up, reduce latency. Download / upload speed of CDMA20001xEV-DO Rev.0 is 2.4576Mbps / 157Kbps, Rev.A is 3.1Mbps / 1.8Mbps and Rev.B is 9.3Mbps / 5.4Mbps, much faster than public GPRS and EDGE technology on GSM network.
The next step of CDMA20001xEV-DO technology is CDMA20001xEV-DV technology (1x Evolution Data and Voce). CDMA20001X EV-DV includes subsequent versions of CDMA20001XEV-DO: Rev.C and Rev.D. Download / upload speeds of CDMA20001xEV-DV Rev.C are 2.4576Mbps / 307Kbps and Rev.D are 3.1Mbps / 1.8Mbps (like Rev.A).
Based on this high-speed platform, top speed 2.4Mbps (Rev.0), suppliers can create a lot of services for customers, such as mobile applications in cars, trucks, taxis. , commercial services, advertising, performances, conferences, replying letters . and Rev.A's radio communication technology help reduce latency and have higher speeds than Rev.0 for translation VoIP service and phone with picture on the same carrier channel.
Currently, S-Fone is providing services based on CDMA20001xEVDO technology (download speed is 2.4Mbps, uploading 380Kbps) this attractive: VOD / MOD (watching movies, television / listening to music directly on electricity mobile phones) and Mobile Internet (mobile Internet - connect to the Internet for computers using S-Fone network phones). To use this service, you must be a S-Fone subscriber along with a mobile phone or USB modem supporting CDMA20001xEVDO technology (refer to B0810_77).
Being licensed for 3G deployment, does not mean that Telco can only use 3G technologies. Based on their own infrastructure, financial capacity and business strategy, operators can choose 3G technology; 3.5G even 3.75G or 4G.
The basic difference between CDMA & GSM *
GSM (Global System for Mobile communications) and CDMA (Code Division Multiple Access - Multi-access code division) are two advanced mobile communication systems widely applied across world. In particular, GSM networks account for more than 74% of the worldwide network. GSM is Europe's digital information system, using TDMA (Multi-temporal division access) method with time slot structure to create flexibility in voice, data and control information. . GSM digitizes and compresses data, then transfers to the transmission channel by two different user data streams, each occupying a separate time slot. The bandwidth initially divided into 200kHz wave channels and then channeled based on the time slot. Users of wave channels take turns sequentially, so there is only one user on a channel and can only be used in very short periods.
Meanwhile, CDMA uses a multiple-access method, divided by code, ie all subscribers of the CDMA network talk on the same broadband band and are distinguished by random code. Each subscriber will be coded with different random codes, then mixed and broadcast on the same frequency band and only recovered at the subscriber device (mobile phone) with random code corresponding.
Technology
GSM
The number of GSM networks is the majority, so it is easy for users to roam (roaming) when moving from one country to another. GSM is superior to CDMA because it uses SIM card, flexibility, security and high security. Users can remove the SIM card on this phone and install it in another device easily. Users have more freedom in selecting terminals.
CDMA
With high frequency reuse frequency reuse and energy control, CDMA allows the management of the number of subscribers to be 5-20 times higher than GSM. Improved call quality: CDMA provides clearer and clearer sound quality than other technology-based mobile systems. High security. Less battery life, longer talk time and smaller device size. Provides a variety of high-speed data transfer and addition services. The coverage radius of the base station is larger than GSM.