The introduction of GSM-based mobile technology and CDMA-based, maybe this can be one consideration if we want to buy a mobile device, because current mobile devices is no longer used merely to communicate, but has become a fairly high mobility among those who are busy with business. They had no need to go to the cafe or install telephone wiring network that may be out, all this has to be enjoyed by just using a cell phone. At the moment we want to surf ria or send email and so forth around the world of the Internet, can and very easy to use phone as a modem in the computer we have, the price is also very cheap to say, let's explore and learn in advance about the network technology GSM and CDMA mobile phones
GSM Technology
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Current GSM data services have been able to serve SMS and 14.4-Kbps data circuitswitched service for data and fax. 14.4 Kbps data transfer rate is relatively slower when compared to wireline modems, which generally has a speed of 33.6 and 56 Kbps. To enhance the capability of data services on GSM, the GSM operators and infrastructure providers (Provider) has to specify the development of a new generation of GSM GSM Pase II is capable of providing technology services as follows:
1. (2G) High-Speed Circuit-Switched Data (HSCD) by using some ciruit cannel
2. (2.5G) GPRS to provide access packet radio service to external packet data networks such as X.25 or the Internet.
3. (2.75G) Enhanced Data Rate for GSM Evolution (EDGE) which uses a new modulation scheme to generate greater value for throughput up to three times when compared with GPRS and HSCD.
4. (3G - 3G/WCDMA - Universal Mobile Telecommunications System (UMTS), a new wireless technology that uses the infrastructure deployment.
5. Development-development that enables the delivery of GSM / data communication with a value greater throughput, better spectral efficiency, and time of call setup semakian low.
· Technology GPRS
General Packet Radio Service or better known as GPRS is a data transmission service based on GSM network data packets. With the GPRS technology is making mobile data transmission on GSM networks become faster, cheaper and user-friendly than ever. GPRS also introduces the packet switching and Internet Protocol in mobile networks so as to provide a service speed of data transfer and accessing services via the internet network / mobile network to its users.
GPRS technology was developed in order to allow GSM operators will meet the needs of wireless data packet services is the impact of the explosion in growth of the Internet and corporate intranets. With GPRS technology which has the advantage of packet-switched network for data transmission is bursty, it requires no connection setup in advance and allows the use of a common connection to maximize the efficiency of resource use.
GPRS technology development objectives for GSM network operators is to provide data transmission services and network access the Internet faster and cheaper.
The GPRS packet switching means that GPRS radio resources will be used only when users are sending or receiving data packets. With the technology-switchign package is then a radio channel or bandwidth can be used jointly by two or more users concurrently. Thus the packet switching mode allows better optimization in the utilization of radio resources in GPRS network for data applications. This allows the application of data transmission has the following characteristics:
1. Infrequent data transmission
2. Frequent Transmission of small blocks of data transmission using the frequency data blocks with small size as an example to download several web pages (html) via a web browser application requires only a few kilobytes.
3. Infrequent Transmission of larger data blocks. As an example of a transaction to access the data storage on a database that requires a block of data is more / bigger so it takes a long time.
4. Asymmetrical the between uplink and downlink throughput as an example in the data retrieval application on the server which is used to transmit uplink command signal (signaling command) while the downlink is used to receive data in response to the request.
GPRS has been widely used to support applications related to data communication services. Some examples of applications that use GPRS technology include chat, sending data / text based and visual information, image data transmission / image, web browsing, file transfer, including MMS (Multimedia Message Service), application of corporate e-mail and the Internet, SMS, etc. . GPRS can transmit data to the applications on top of up to 0.22 bps to 111 Kbps.
GPRS mobile station or GPRS terminals are grouped in several classes, each of which has advantages / capabilities differ according to community needs for data communications. GPRS terminal classes that include the following:
1. Class A, namely a mobile station that can make or receive calls either GPRS or GSM simultaneously.
2. Class B, which is a mobile station that can make and receive calls either GPRS or GSM but not simultaneously.
3. Class C, the mobile station that can be set manually whether GSM or GPRS mode.
· Shipping and receiving data on a GPRS mobile station
Geographical area covered by the GPRS network is divided into smaller areas called cells and routing areas. A cell is an area that dilayanai by the set / the set of radio base stations. When a GPRS mobile station to perform data transmission or reception of data, then the mobile station will be looking for the strongest radio signal that can be found among the existing base station stationnbase. After finding the strongest radio signal from a base station, the mobile station will send notification to the network from cell to select the base stations that transmit radio signals menngunakannya strongest and services to serve the sending or receiving data. Periodically the mobile station will listen to the radio signal from the set of base stations, and if it is found that there is another base station that has a stronger radio signal from the current base station, the mobile station will replace the base station with a new base station has a signal more powerful radio. This process is referred to reselect. Routing area is the set of cell-cell or group of adjacent areas. Routing area will be useful in the process of location-updating traffic and paging traffic. For mobile stations that are actively doing the process of sending or receiving data packets, then the search process is done through the cell site (the network will keep track of the cell which is currently being used). As for the condition of the moble station in a state of inactivity or idle, then the search is based on the routing area (the network will keep track of the routing area).
Use of GPRS mobile stations on the application using the GPRS data transmission is generally made with client / server architecture. In principle client is the agent that sends requests to the server for processing by the server and the results are sent back to the client. And the role of the GPRS mobile station can be set as a client mode or server mode. GPRS mobile station in general act as a client, for example, is when a GPRS mobile station digunaan to access the internet, intranet, or to initialize the database with GPRS communication. GPRS mobile station can also act as a server for example when used for applications where monitoring telemetery GPRS mobile station associated with the device / devices such as cameras to monitor or retrieve data telemetry.
then when a GPRS mobile station will use the services of wireless data packet network, the first mobile station to attach to a Service GPRS Support Node (SGSN). When the SGSN receives a request from a mobile station, then the SGSN will ensure whether to provide services such request. Some factors to consider are as follows:
1. Whether the user is a subscriber mobile station of the GPRS services or not. Pengecekkan process (verification) subcription information from the mobile station is called authorization.
2. Pencekkan process (verification) of information about the identity of the mobile station. This is referred to as authentication.
3. Pengecekkan to the level of QoS (Quality of Service) of the request service requested by the mobile station. Things to do include the verification of the ability of subscribers to pay the requested service and also verify the ability of networks to provide services as requested (the same time serving a service network to other users).
4. Having decided to accept the request, then the SGSN will store the data track of the mobile station so knowing the location where the data packet must be sent / diroutekan to the mobile station (receiving process data packets).
The process of attachment to the SGSN is not a guarantee that the process pegiriman data packets can be done. In order for mobile statins can make the process of sending data packets, then the mobile subscriber must first activate a PDP address (eg IP address).
PDP address is addresess network layer (OSI model layer 3). GPRS system supports both X.25 network layer protocol or IP. Because of that PDP address can be X.25, IP, or both. Each PDP address is stored and identified (anchored) on a Gateway GPRS Support Node (GGSN). All the traffic of data packets sent from a public data packet network to the PDP address will go through the GGSN. When the mobile station to process the data transmission, in addition to attach to the SGSN, then the mobile station must also be activating a PDP address. PDP address to build an association between the SGSN to the GGSN that the information stored in the PDP context. A mobile station to attach to only one SGSN, but can activate some PDP addresses may be anchored by a different GGSN.
When the mobile station has attached to the SGSN and activate a PDP address, then the mobile station is ready to communicate with other devices. For example GPRS mobile can communicate with a computer system connected to an X.25 network or IP network. Thus the process of sending data (data transfer) and revenue data (receiving data) using GPRS through the process as follows:
1. Setup a connection to the GPRS network (done separately by the GSM network)
2. Mobile station GPRS attach procedure.
Things that are done include:
a. Mobile station to request attachment to the SGSN.
b. SGSN autentication to perform authorization and requirements of the mobile station.
c. SGSN verifies the QoS service level requested by the mobile station.
d. If the attachment request is received, then the next and maintain SGSN will save the location data (tracks) with the mobile station to maintain a database of mobile station locations of the HLR and MSC / VLR.
3. To be able to perform data transmission, then the mobile station will activate the PDP address. Opera-needed to activate the PDP address is stored in the PDP context.
GPRS Technology Utilization
The main objective of GPRS technology development is to facilitate the interconnection between a mobile device with a packet-switch network to other data through kajaringan access the internet. With the introduction of the GPRS packet mode, it allows the integration between mobile telephony and Internet technologies into mobile Internet technology (mobile internet technology). This technology enables mobile phone users (mobile phone) service gets a new / additional as follows:
1. Client-Server Services, which allows accessing data stored in a database. Typical application is accessing the Web through a browser.
2. Messaging Services is intended for communication between individual users by utilizing the storage server for handling messages as a temporary message storage / intermediate before being accepted by the user. Conoth result is an application service Multimedia Message Service (MMS) which is used for multimedia data transmission over GSM network using a cellular phone.
3. Real-time conversational Services that provide two-way communication services to users in real-time. Some examples of its application is on the Internet and multimedia applications such as Voice over IP and video conferencing.
4. Tele-action services
GSM-GPRS modem (GPRS terminal / GPRS mobile station) GSM-GPRS modem (GPRS terminal / mobile station) is a mobile device that allows the user / mobile users perform data communications using GPRS technology. GSM-GPRS modems are present in the market has different characteristics. Among the characteristics of GSM-GPRS modems are antaralain as follows:
1. Or treeband Dualband GSM-GPRS modem (EGSM 900/1800 MHz and EGSM 900/1800/1900 MHZ).
2. Designed for GPRS-based applications, data, fax, SMS, and voice applications.
3. Input voltage between 8 volts to 40 volts.
4. 8 mA of input current during the off state (idle mode) and, 150 mA when the communication takes place (active) in the GSM 900 @ 12 V and 110 mA when the communication takes place in communication GSM 1800 @ 12 V
5. Temperature / temperature range from -20 to 55 degrees centigrade.
6. Overall Dimensions 80mmX62mmX31mm / Weight: 200 gr
7. Interface with RS-232 communications via D-type connector with 9 pins TYPE
8. voice communication interfaces with RJ11 connectors
9. Power supply with Molex 4 pin connector that has
10. Interce communication with SMA antenna connector
11. Togle Spring SIM holder
12. Red LED power on
13. Green LED status of GSM / GPRS module
To perform data communications (either sending or receiving data) on the GSM-GPRS modem, then use the command AT + Command.
GPRS Tariff
GPRS rates vary depending on the GSM telecommunications network provider.
CDMA Technology
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In the mid 1990s, the International Telecommunication Union (ITU) began efforts to establish telecommunications services to users anywhere and anytime. The goal is interoperability of mobile systems (mobile) who could provide value added services. In 1998, the ITU Radio issued a proposal Transmission Technology (RTT) for International Mobile Telecommunications-2000 (IMT-2000), the formal name for the 3G standard. IMT-2000 approved three standards for 3G W-CDMA, CDMA2000, and TDSCDMA. W-CDMA (Wideband Code Division Multiple Access) is supported by the European Telecommunications Standards Institute (ETSI) and the GSM operators in Europe and elsewhere. While CDMA2000 is supported by the North American CDMA community, led by the CDMA Development Group (CDG). The third standard (TDSCDMA) supported in China. Early in 1998, W-CDMA is included in the standard ETSI UMTS (Universal Mobile Telecommunications System).
W-CDMA has been widely supported by GSM carriers worldwide. Because W-CDMA requires at least 5 MHz spectrum, which supports WCDMA operators
have to buy new spectrum, with the cost of billions of dollars, to use this technology. W-CDMA promises the use of voice and data service with a maximum capacity of 2 Mbps over 5 MHz channel. But the field, operators believe that W-CDMA can only handle up to 384 kbps.
CDMA2000 operators are widely used by CDMA (cdmaOne) that already exist. CDMA2000 is designed to operate on the same spectrum with cdmaOne networks that do not require new spectrum. To obtain this, CDMA offers a two-stage evolutionary path. The first stage is called CDMA2000 1xRTT technology that uses a 1.25 MHz CDMA channel to acquire 153 Kbps data rate and twice the voice capacity compared to cdmaOne. Spectrum that is released due to the use 1xRTT now be used for the next stage of evolution, CDMA2000 1xEV-DO.
CDMA2000 1xEV-DO offers data transfer speeds of up to 2.4 Mbps. In this paper the discussion is limited to that use CDMA2000 operators in Indonesia. CDMA technology separates the user's call to each other using the code, not the frequency. The result, all CDMA frequencies can be used all the cells, thus increasing the total number of voice channels available and the capacity of the system as a whole. CDMA is a spread spectrum technology, which means he is spreading the information contained specific signals into the bandwidth that is greater than the original signal. Spread spectrum has substantially increased bandwidth of the signal carriers of information, far above the basic communication needs. Increased bandwidth, although not required for communication, can reduce the adverse effects of interference.
CDMA2000
CDMA2000 goal is to provide 2.5G and 3G services using a system consisting of a system TIA/EIA-41 IS-95A, B, and cdmaOne
There are several types of CDMA2000 namely:
• CDMA2000 1xRTT
1xRTT specifications developed by the Third Generation Partnership Project 2 (3GPP2), a partnership consisting of five telecommunications standards bodies: CWTS in China, ARIB and TTC in Japan, TTA in Korea and TIA in North America. CDMA2000 1xRTT offers service with speeds up to 153 kbps in a small range of the spectrum (1.25 MHz per carrier).
• CDMA2000 1xEV-DO
1xEV-DO, also known as 1X-EV Phase One, is an improvement by putting voice and data on separate channels to provide data transmission at a speed of 2.4 Mbit / s.
• CDMA2000 1xEV-DV
EV-DV, or 1X-EV Phase Two promises data speeds ranging from 3Mbps to 5Mbps. Until now there have been eight proposals were submitted to the 3GPP2 standards committee for the design of EV-DV.
• CDMA2000 3xRTT
3xRTT is a standard IMT-2000 (3G), which approved the ITU. He is part of what is called the ITU as IMT-2000 CDMA MC. It uses the 5 MHz spectrum to deliver data speeds ranging from 2 to 4 Mbps.
3.3 CDMA in Indonesia
Currently in Indonesia have been there at least four CDMA operators. Telkom with its Flexi, Fren Mobile-8 with her, Bakrie Telecommunication with its Esia, and Indosat StarOne her. The technology used by CDMA operators are still mostly limited to the CDMA 1xRTT. While there are operators, namely Mobile-8, which offers CDMA 1xEV-DO for certain areas in Jakarta.
Speed of data transfer that occurs is far from the actual capacity of CDMA. For example, Telkom Flexi using CDMA 1xRTT, which should be capable of reaching speeds of 153 kbps, is currently only opened at effective speeds of 30 to 70 kbps.
For data access costs, tariffs imposed each operator tends to equal the Rp 5/kb.
Comparison of GSM and CDMA
Transfer speed
CDMA offers higher data transfer rates versus GSM. With CDMA2000 1xRTT technology theoretically we can deliver data up to 153 kbps. GPRS while only reaching 111 kbps.
GPRS coverage area to more spacious than CDMA because GPRS uses the GSM technology which first existed, more established and covers an area larger area when compared to CDMA.
