Dissecting Network Technology GSM phone and CDMA phone

Introduction of mobile technology-based GSM and CDMA-based, maybe this could be one consideration if we want to buy a mobile device, because current mobile devices is no longer used merely to communicate, but have become high enough mobility among those who are busy with business. They had no need to go to cafes or installing telephone cables that may have missed, this is all can 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, are able and easy to use the phone as a modem in the computer we have, the price is also very cheap to say, let's explore and learn first about the network technology GSM phone and CDMA phone

GSM Technology


We have been able to serve the GSM data services SMS and 14.4-Kbps data circuitswitched service for data and fax. The speed of 14.4 Kbps data transfer is relatively slower compared to wireline modems, which generally has a top speed 33.6 and 56 Kbps. To enhance data service capabilities on GSM networks, the operators and the GSM infrastructure providers (provide) has to specify the development of a new generation of GSM GSM Pase II is capable of providing technology services as follows:

1. High-Speed Circuit-Switched Data (HSCD) by using several ciruit cannel

2. GPRS provide access to the radio packet to an external data packet networks such as X.25 or the Internet.

3. Enhanced Data Rate for GSM Evolution (EDGE) which uses a new modulation scheme to produce value greater throughput up to three time when compared to GPRS and HSCD.

4. Universal Mobile Telecommunications System (UMTS), a new wireless technology that uses the infrastructure deployment.

5. GSM developments are allowing transmission / communication of data with values greater throughput, spectral efficiency is better, and call setup time low semakian.

GPRS technology

General Packet Radio service, or better known as the GPRS is a data transmission service based on the data packet GSM network. With the GPRS technology is making mobile data transmission on GSM networks become faster, cheaper and user-friendly than ever. GPRS also introduces a packet switching and Internet Protocol in mobile networks that deliver services and data transfer speed Internet network access services through the device / mobile network to its users.

GPRS technology is developed in order to allow GSM operators to meet the needs of wireless data packet service, which is the impact of the explosion of growth of the Internet and corporate intranets. With GPRS technology which has the advantage of packet-switched for data transmission is bursty, it does not require prior connection setup and allows you to use a common connection to maximize the efficiency of resource use.

GPRS technology development objectives for the GSM network operator 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 sending or receiving data packets. With the technology-switchign package is then a radio channel or the bandwidth can be shared by two or more users concurrently. Thus the packet switching mode allows a better optimization of resource use in the GPRS radio network for data applications. This allows the application of data transmission has the following characteristics:

1. Infrequent transmission of data

2. Frequent transmision of small blocks of data transmission frequency of the use of 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 transmision of larger data blocks. For example, transactions to access the database storing data on a block of data requires more / bigger and thus require a long time.

4. Asymmetrical throughput between the uplink and downlink as an example of data acquisition application on a server which is used for uplink command signal (signaling command) while the downlink is used to receive data in response to the request.

GPRS has been used to support applications related to data communication services. Some examples of applications that use GPRS technology, including a chat, sending data / text-based information and visual image data / image, web browsing, file transfer including MMS (Multimedia Message Service), the application of corporate e-mail and the Internet, SMS, etc. . GPRS can transmit data for applications on up to 0.22 bps to 111 Kbps.

GPRS GPRS mobile stations or terminals are grouped in several classes, each has advantages / capabilities that differ according to the needs of the community will be the data communications. Classes of GPRS terminals that include the following:

1. Class A, which is 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 or receive calls and either GPRS or GSM but not simultaneously.

3। Class C, the mobile station that can be set manually whether GSM or GPRS mode.

Sending and receiving data in GPRS mobile stations

Geographical area covered by the GPRS network is divided into the smaller areas called cells and routing areas. A cell is the area dilayanai by set / sets of radio base stations. When a GPRS mobile station to perform data transmission or reception of data, the mobile station will search for the strongest radio signals that can be found between the base station is stationnbase. After finding the strongest radio signal from a base station, the mobile station will send a notification to the network from cell to select the base station that sends the strongest radio signals and services to serve menngunakannya sending or receiving data. Mobile station periodically to listen to the radio signals from base stations are set, and if it is found that there is another base station has a stronger radio signal from the current base station, the mobile station will replace the base station with a new base station which has a signal more powerful radio. This process is called the reselect. Routing area is a set or group of cell-cell adjacent areas. Routing area will be useful in the process of updating the location-paging traffic and traffic. For mobile stations that are actively being made the process of sending or receiving data packets, then the location search process is carried out through the cell (the network will keep track of the cell that is currently being used). As for conditions that moble station are off or idle, then the search is based on the routing area (the network will keep track of the routing area).

GPRS mobile station utilization in data transmission applications using GPRS are generally made with the architecture of client / server. In principle client is the agent that sends requests to a server for processing by the server and the results sent back to the client. And the role of GPRS mobile stations can be set as a client mode or server mode. GPRS mobile station generally serves as a client, for example is when the GPRS mobile station to perform digunaan internet access, intranet, or initialize the database with GPRS communications. GPRS mobile station can also act as a server for example when used for monitoring applications where telemetery GPRS mobile station associated with the device / devices such as cameras to monitor or retrieve telemetry data.

then when a GPRS mobile station will use the services of wireless data packet network, first the mobile station to attach to the Service GPRS Support Node (SGSN). When the SGSN receives a request from a mobile station, the SGSN will ensure whether to provide services such request. Some factors to consider are as follows:

1. Does a mobile user is a subscriber 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 called the authentication.

3. Pengecekkan to level QoS (Quality of Service) of the requested service request by the mobile station. This does include a verification process on the subscriber's ability to pay the requested service, and also verifies the network's ability to provide appropriate services required (at the same time was serving network service to other users).

4. Having decided to accept the request, the SGSN will keep track of data from the mobile station so that the location where the data packet should be sent / diroutekan into the mobile station (receiving the data packet).

The process of attachment to SGSN does not guarantee that the data packet pegiriman process can be done. In order for mobile statins are able to process data packet transmission, the mobile subscriber must first activate a PDP address (such as IP address).

PDP is a network layer address addresess (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 recognized (anchored) in a Gateway GPRS support node (GGSN). All the traffic data packets sent from a public data packet network to a PDP address to the GGSN. When the mobile station data transmission process, then in addition to attach to the SGSN, the mobile station must also activate a PDP address. PDP address to build an association between the SGSN with the GGSN that the information is 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 done attach 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 the X.25 network or IP network. Thus the process of data transmission (data transfer) and revenue data (receiving data) using GPRS done through the following process:

1. Setup a connection to the GPRS network (done separately with the 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 the requirements of autentication mobile station.

c. SGSN verify the QoS service level requested by the mobile station.

d. If the attachment request is accepted, then the SGSN will meyimpan and maintains the location data (tracks) with the mobile station to maintain the database of mobile station location HLR and MSC / VLR.

3. To be able to perform data transmission, the mobile station will activate PDP address. Infromasi required to activate the PDP address is stored in the PDP context.

GPRS Technology Utilization

The main purpose of the GPRS technology development is to facilitate the interconnection between a mobile device with packet-switching network of the other data through the internet kajaringan access. With the introduction of GPRS packet mode, it enables the integration of mobile telephony technology and the Internet into mobile Internet technology (mobile internet technology). This technology enables mobile phone users (mobile phone) get new services / enhancements as follows:

1. Client-Server Services that allows accessing data stored in a database. Example of this application is accessed via WEB browser.

2. Messaging Services is intended for communication between individual users by utilizing storage server for handling the message as a temporary message storage / intermediate before it is received by the user. Conoth result is an application service Multimedia Message Service (MMS) which is used for data transmission of multimedia messages via the GSM network using cell phone.

3. Real-time conversational Services which provides 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 terminals / GPRS mobile station) GSM-GPRS modem (GPRS terminal / mobile station) is a mobile device that allows the user / mobile user data communications using GPRS technology. GSM-GPRS modem is present in the market has different characteristics. Among the characteristics of GSM-GPRS modem is antaralain as follows:

1. GSM Dualband or treeband-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. Input current 8 mA when inactive state (idle mode) and, 150 mA when the communication (active) in the GSM 900 @ 12 V, 110 mA as well as the communication in communication GSM 1800 @ 12 V

5. Temperature / temperature range from -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. communications interface with voice RJ11 connectors

9. Molex power supply with a 4 pin connector has

10. Interce communication with SMA antenna connector

11. SIM holder spring Togle

12. Red LED power on

13. Green LED status of GSM / GPRS module

To perform data communications (either sending or receiving data) in the GSM-GPRS modem, then use the command AT + Command.

CDMA


In mid 1990, the International Telecommunication Union (ITU) began efforts to develop telecommunications services to users anywhere and anytime. The goal is interoperability mobile systems (mobile) that can provide value-added services. In 1998, the ITU Radio Transmission proposals issued Technology (RTT) for International Mobile Telecommunications-2000 (IMT-2000), the formal name for the 3G standard. IMT-2000 approved three standards for 3G: the W-CDMA, CDMA2000, and TDSCDMA. W, CDMA (Wideband Code Division Multiple Access) is supported by the European Telecommunications Standards Institute (ETSI), and 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) supported in China. At the beginning of the year 1998, W-CDMA included in the ETSI standard UMTS (Universal Mobile Telecommunications System).

W-CDMA has been widely supported by GSM operators throughout the world. Because the CDMA W-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-promising use of CDMA voice and data services with a maximum capacity of 2 Mbps over 5 MHz channel. But the field, operators believe that the W-CDMA only handle up to 384 kbps.

CDMA2000 operators are widely used by CDMA (cdmaOne) that already exists. CDMA2000 is designed to operate on the same spectrum with cdmaOne networks that do not require new spectrum. To get this, CDMA offers a two-stage evolutionary line. The first stage is a technology called CDMA2000 1xRTT, which uses a 1.25 MHz CDMA channel to acquire 153 Kbps data rate and twice the voice capacity of cdmaOne compared. Spectrum that is released for use 1xRTT can now be used for the next stage of evolution, CDMA2000 1xEV-DO.

CDMA2000 1xEV-DO offers data transfer speeds up to 2.4 Mbps. In this paper the discussion is limited to the use CDMA2000 operators in Indonesia. CDMA technology separates users call each other using the code, not the frequency. The results, all CDMA frequencies can be used all the cells, thus increasing the total number of voice channels are available and the overall system capacity. CDMA is a spread spectrum technologies, which means he spread the information contained specific signals into the bandwidth is greater than the original signal. Spread spectrum has been substantially increased the information carrier signal bandwidth, well 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 services using 2.5G and 3G systems TIA/EIA-41 system consisting of the IS-95A, B, and cdmaOne

There are several types of CDMA2000 are:

• CDMA2000 1xRTT

1xRTT Specification 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 service offers speeds of up to a range of 153 kbps in a small 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.

• 1xEV-DV CDMA2000

EV-DV, or 1X-EV Phase Two promising data speeds ranging from 3Mbps to 5Mbps. To date there have been 8 proposal submitted to 3GPP2 standards committees to draft EV-DV.

• CDMA2000 3xRTT

3xRTT is an IMT-2000 standard (3G) approved ITU. He is part of what is called the ITU as IMT-2000 CDMA MC. He uses 5 MHz spectrum to provide data rates ranging from 2 to 4 Mbps.

3.3 CDMA in Indonesia

Currently in Indonesia has no least four CDMA operators. Telkom with its Flexi, Mobile-8 with his Fren, Esia Bakrie Telecommunication with him, and StarOne Indosat with her. The technology used by CDMA operators are still confined mostly to the CDMA 1xRTT. Although there are operators, which is Mobile-8, which offers CDMA 1xEV-DO to certain areas in Jakarta.

The speed of data transfer occurs is still far from actual CDMA capacity. For example, Telkom Flexi using CDMA 1xRTT, which should be able to reach speeds of 153 kbps, now opened in an effective speed of 30 to 70 kbps.

For data access fees, imposed tariffs of individual operators tend to equal the USD? / Mb.

Comparison of GSM and CDMA

Transfer speed

CDMA offers data transfer speeds over GSM appeal. With CDMA2000 1xRTT technology, we can theoretically deliver up to 153 kbps data. GPRS while only about 111 kilobits per second.

Cost

List the cost of data services to offer mobile phone operator in Indonesia can be seen in the table below. CDMA operators charge for data services tend to equal the USD. ? / kb. Greater variation seen in opeartor GSM, data service rates range from Rp. ? / kb s.d. USD? / Kb. When we consider the service charge for each kilobyte of data in CDMA cellular card is cheaper about 2 to 10 times the GSM card.