GSM dan berbasis CDMA, mungkin ini dapat menjadi salah satu bahan pertimbangan jika kita ingin membeli sebuah perangkat ponsel, sebab saat ini perangkat ponsel bukan lagi digunakan hanya sekedar berkomunikasi, melainkan sudah menjadi mobilitas yang cukup tinggi dikalangan mereka yang sibuk dengan">The introduction of GSM-based mobile technology and CDMA-based, maybe this could be one consideration if we want to buy a mobile device, because current mobile devices are 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 a cafe or installing telephone cable network that may have been left behind, all this has to be enjoyed by just using a mobile phone. At the moment we want to surf or send email ria and others around the world of the Internet, very able and easy to use the phone as a modem in the computer we have, about the price also very cheap to say, let us learn and we explore more advance about network technology GSM and CDMA mobile phones
GSM Technology ==============
Currently, GSM has been able to serve data services and SMS messages circuitswitched 14.4-Kbps data service for data and fax. 14.4 Kbps data transfer rate is relatively slower compared to wireline modems, which generally has a speed of 33.6 and 56 Kbps. To improve the capability of data services on GSM networks, the GSM operators and infrastructure providers (Provide) has been specifying the development of a new generation GSM GSM Pase II is capable of providing technology services as follows:
1. (2G) High-Speed Circuit-Switched Data (HSCD) using several ciruit cannel
2. (2.5G) GPRS to provide radio packet access service to an external data packet 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 produce value greater throughput of up to three times when compared with GPRS and HSCD.
4. (3G - 3G/WCDMA - Universal Mobile Telecommunications System (UMTS), new wireless technologies that use the infrastructure deployment.
5. GSM developments memungkinakan delivery / communication of data 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 that deliver data transfer speeds and service network accessing the Internet through devices / mobile networks to its users.
GPRS technology was developed in order to allow GSM operators meet the needs of wireless data packet service, which is the impact of the explosion in growth of the Internet and corporate intranets. With GPRS technology which has the advantage of packet-switched networks for data transmission is bursty, it requires no connection setup in advance and allows the use of a common connection to maximize the efficient use of resources.
The purpose of the GPRS technology developed 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 a better optimization in the utilization of radio resources in GPRS network for data applications. This allows application data transmission characteristics as follows:
1. Infrequent data transmission
2. Frequent Transmission of small blocks of data transmission frequency using the data blocks with small size as an example to download some 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 in databases that require more data block / greater and thus require a long time.
4. Between Asymmetrical uplink and downlink throughput as an example in taking the data on a server application 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, such as chat, data transmission / visual and text-based information, transmission of image data / image, web browsing, file transfers such as MMS (Multimedia Message Service), E-mail corporate applications 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 into several classes, each of which has its own advantages / capabilities differ according to the data communications needs of the community. Classes GPRS terminal are as follows:
1. Class A, namely a mobile station that can make or receive calls either GPRS or GSM simultaneously.
2. Class B, namely 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 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 set / sets 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 to serve the strongest and menngunakannya transmission or reception of data services. Periodically mobile station will listen to the radio signals from the set of base stations, and if it is found that there is another base station which has a much stronger radio signals from base stations today, then the mobile station will replace the base station with a new base station has a signal more powerful radio. This process is referred to as 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 active is in the process sending or receiving data packets, then the search process conducted by the level of cell sites (the network will keep track of the cell which is currently being used). As for the moble station in a state of inactive 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 sending the request to the server for later 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 the GPRS mobile station digunaan to access the internet, intranet, or initialize the database with GPRS communication. GPRS mobile station can also act as a server for example when used for monitoring applications telemetery where 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 the Service GPRS Support Node (SGSN). When the SGSN receives a request from a mobile station, the SGSN will make sure whether these will provide the service request. Some factors to be considered 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. It is conducted including the verification process on the ability of subscribers to pay for the service requested and also verify the ability of networks to provide the requested service according to (while simultaneously serving network service to other users).
4. Having decided to accept the request, then the SGSN will store the data track of the mobile station so that knowing the location where the data packet should be sent / diroutekan to the mobile station (process of receiving data packets).
The process of attachment to the SGSN is not a guarantee that the process pegiriman data packet can be made. For mobile statins can make the process of sending data packets, the mobile subscriber must first activate a PDP address (such as IP address).
PDP address is addresess network layer (OSI model layer 3). GPRS system supports both X.25 network layer protocol or IP. Therefore, the PDP address can be X.25, IP, or both. Each PDP address is stored and recognizable (anchored) on a Gateway GPRS Support Node (GGSN). All traffic data packet is sent from a public data packet network to the PDP address will be through the GGSN. When the mobile station to process the data transmission, in addition to attach to the SGSN, then the mobile station will also have to activate a PDP address. PDP address to build an association between the SGSN with 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 to communicate with a computer system connected to the X.25 network or an IP network. Thus the process of sending data (data transfer) and received data (receiving data) using GPRS through the process as follows:
1. Setup a connection to the GPRS network (done separately with a GSM network)
2. Mobile station GPRS attach procedure.
Things that do include:
a. Mobile station to request attachment to the SGSN.
b. SGSN perform authorization and autentication against the 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 SGSN will then save and maintain location data (track) mobile station to perform a database maintained on the location of mobile station that is 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
The main objective of the GPRS technology development is to facilitate the interconnection between a mobile device with packet-switched networks 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) to get the new service / extra as follows:
1. Client-Server Services that 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 the message as a temporary message storage / intermediate before being accepted by the user. Conoth result is an application service Multimedia Message Service (MMS) used for data transmission of multimedia messages via the 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 modem that is present in the market has different characteristics. Among the characteristics of GSM-GPRS modem is 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 when the condition is not active (idle mode) and, 150 mA when communications take place (active) in the GSM 900 @ 12 V, 110 mA current and ongoing communication in communication GSM 1800 @ 12 V
5. Temperature / temperature range between -20 to 55 degrees Celsius.
6. Overall Dimensions 80mmX62mmX31mm / Weight: 200 gr
7. Communication interface with RS-232 through D-type connector with 9 pins TYPE
8. voice communication interface with RJ11 connectors
9. Power supply with a 4 pin Molex connector
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 Tariffs
GPRS rates vary depending on the GSM telecommunications network provider.
CDMA Technology ==============
In the mid-1990s, the International Telecommunication Union (ITU) began efforts to develop telecommunication services to users anywhere and anytime. The goal is interoperability of mobile systems (mobile) that could provide value-added services. In 1998, ITU issued a proposal Radio 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 supported by the North American CDMA community, led by the CDMA Development Group (CDG). The third standard (TDSCDMA) is supported in China. Beginning in 1998, W-CDMA that is included in the standard ETSI UMTS (Universal Mobile Telecommunications System).
W-CDMA has been broadly supported by GSM operators worldwide. Because W-CDMA requires at least 5 MHz of spectrum, which supports WCDMA operators
must 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 the W-CDMA can only handle up to 384 kbps.
CDMA2000 operators are widely used by CDMA (cdmaOne), which already exists. 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 paths. The first stage is called CDMA2000 1xRTT technology, which uses a 1.25 MHz CDMA channel to acquire 153 Kbps data rate and twice the voice capacity compared to cdmaOne. Spectrum that are released due to the use 1xRTT now be used to stage the next evolution, CDMA2000 1xEV-DO.
CDMA2000 1xEV-DO offers data transfer speeds up to 2.4 Mbps. In this paper the discussion is limited to that use CDMA2000 operators in Indonesia. CDMA technology separates users call one another using the code, not the frequency. As a result, all CDMA frequency can be used all the cells, thus increasing the total number of voice channels available and the overall system capacity. CDMA is a spread spectrum technology, which means he is spreading the information contained specific signals into the bandwidth is greater than the original signal. Spread spectrum has been substantially increase the bandwidth of the signal carriers of information, far above the basic communication needs. Increased bandwidth, although not required for communication, can reduce the harmful effects of interference.
CDMA2000
CDMA2000 goal is to provide 2.5G and 3G services using a system consisting of 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 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 speeds 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 are 8 proposals submitted to the 3GPP2 standards committee for the design of EV-DV.
• CDMA2000 3xRTT
3xRTT is a standard IMT-2000 (3G) approved ITU. It is part of what is called the ITU as IMT-2000 CDMA MC. He uses 5 MHz of spectrum to provide data rates 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, Mobile-8 with its Fren, Esia Bakrie Telecommunication with her, and her Indosat StarOne. The technology used by CDMA operators still mostly limited to the CDMA 1xRTT. Although there are operators, which is Mobile-8, which offers CDMA 1xEV-DO for certain areas in Jakarta.
The speed of data transfer that occurs is far from the actual CDMA capacity. For example, Telkom Flexi using CDMA 1xRTT, which should be able to reach speeds of 153 kbps, currently only open at effective speeds of 30 to 70 kbps.
For data access costs, tariffs imposed on each operator tends to equal the USD 5/kb.
Comparison of GSM and CDMA
Transfer speed
CDMA offers higher data transfer rates versus GSM. With CDMA2000 1xRTT technology, we can theoretically deliver up to 153 kbps data. While GPRS only reach 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 wider area than CDMA.
Hope can be useful ............ Source: wahanaponsel
Dissecting Network Technology GSM phone and CDMA phone
