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ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING GPRS (General Packet Radio Service) technology. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering /Mobile telephony GPRS is a packet-switched based radio service that enables "always on" connections, replacing labor-intensive and time-consuming dial-up connections. The need for a solution for access from cellular networks to the Internet and local corporate networks has been discussed for many years. Widespread adoption of this kind of technology has been slowed down by coverage, cost, performance, and secure remote access issues in corporate networks. The launch of the GSM-based GPRS (General Packet Radio Service) service has the potential to change this situation and provide "anytime, anywhere" connectivity. GPRS is a packet-switched based radio service that enables "always on" connections, replacing labor-intensive and time-consuming dial-up connections. This service also provides real throughput in excess of 40 kbps - these are about the same speeds as in the case of good terrestrial connections via modem. In general, GPRS (General Packet Radio Service) is the next step from GSM to third generation cellular networks - 3G. GPRS offers faster data transmission over GSM networks with speeds from 9.6 to 115 kbps. This new technology creates the ability for users to make phone calls and transfer data at the same time. (For example, if you have a mobile phone that supports the GPRS function, you can talk on the phone and receive e-mail messages at the same time). The most attractive aspect of GPRS technology for service providers, in addition to lowering the cost of operation, is the ease of management of its use, as well as the new billing capabilities that have become available after switching from switched to packet data. Customers also benefit from the implementation of this technology, as it provides them with many advanced services from the provider, along with completely new ones. GPRS technology has taken mobile systems one step further, making it more convenient and affordable to use media content in small mobile devices. Among other important advantages of GPRS is the more efficient use of the radio spectrum. Users now occupy radio resources only when there is a real data transfer. This essentially means that more users can be served on a single access point while data rates remain high. The improved functionality and efficiency of GPRS is driving down the cost of commercially providing data services. Offering new attractive opportunities to their subscribers thanks to new technology, providers are attracting an increasing number of customers. But the most important advantage of GPRS is the significantly improved quality of data services. QoS features have become quite affordable and can even be measured in terms of reliability, response time, and supported features. New applications developed for GPRS users will be attractive to many mobile customers and allow providers to facilitate the introduction of new services and the modification of old ones. Milestones After this still relatively new service was first introduced to the market and before it finally settled down, several stages of its "formation" can be distinguished. The implementation of GPRS service includes standardization, infrastructure development, network testing, contracting, network deployment, terminal readiness, application development, and so on. These are the main milestones of GPRS implementation: Date Milestone 1999 - 2000, in full Network operators enter into contracts for testing and commercial launch of the GPRS infrastructure. Embedding the GPRS infrastructure in the GSM network Summer 2000 The first testing of GPRS services became possible. Typical data rates are 28 kbps. For example, T-Mobil plans to test GPRS at Expo2000 in Hannover in the summer of 2000 Early 2001 GPRS terminals became available in commercial quantities Throughout 2001 Network operators launched GPRS services into commercial use and deployed a GPRS network. Early adopters begin to regularly use GPRS services for non-voice mobile communications 2001/2 Typical speeds - 56 kbps. New dedicated GPRS applications, higher data rates, capacity expansion solutions 2002 Typical speeds - 112 kbps. Phase 2 GPRS/EDGE goes into practice 2002 GPRS support in new models of GSM mobile phones becomes commonplace, and the use of this service reaches critical mass. (Equivalent to SMS status in 1999) 2002/3 3GSM operates commercially Like the GSM standard itself, the GPRS service has evolved in phases. During the first phase, commercial use of the service was expected to begin in 2000/2001. Point-to-point GPRS solution (sending information to a single GPRS user) is supported, but not point-to-multipoint (sending the same information to several GPRS users at the same time). Phase 2 of GPRS is not yet fully defined, but higher data rates are expected to be supported through the introduction of new existing technologies such as EDGE (Enhanced Data rates for GSM Evolution) in addition to supporting a point-to-multipoint solution. How does GPRS work? GPRS is an ETSI (European Telecommunications Standards Institute) standard for packet switching in GSM systems. Currently, GSM-based networks are the most widespread worldwide and are called second generation (2G) networks. GSM technology uses a variation of TDMA (time division multiple access) and is the most widely used of the three major digital wireless technologies (TDMA, GSM and CDMA). The GSM digitizes and compresses the data, then sends it over the channel with two other user data streams, each in its own time slot (time slot). Operates at a frequency of either 900 MHz or 1800 MHz. GSM has over 120 million users worldwide and is available in 120 countries, according to the GSM MoU Association. Since most GSM network operators have entered into roaming agreements with foreign operators, users continue to use their mobile phones while traveling to other countries. GPRS is the so-called. overlay technology distributed over GSM, CDMA and TDMA networks. This technology uses a new method to efficiently transmit packet data over radio networks. Packet switching technology is based on IP and X.25 methods, both of which are very popular and widely used in many networks. GPRS packet switching works in general in the same way as IP packet switching, that is, data is split into packets and sent to the destination in different ways over the network, then reassembled at the receiving end. GPRS packet switching allows any existing IP or X.25 traffic to send data over the GPRS radio network. GPRS uses a 200 kHz wide radio band, and it is divided into eight channels. The total capacity of the channels is 271 kbps, but each of these channels is capable of transmitting data streams of 14.4 kbps. Theoretically, a speed of 115 kbps is possible, but in real conditions it is used extremely rarely or not at all. An average speed of 48 kbps is the most likely estimate because the access points are shared among multiple users, and the range or location of the receiver will also depend on the available bandwidth. This result is much better than existing mobile communication devices, which provide only 9.6 kbps, can offer. Another important aspect of Internet communication over GPRS - and this is the first such implementation for a broadband network - is that the connection to the Internet is continuous (always "online"), and at the same time it does not have to pull resources from access points to the time when it is not used, because data is only transferred when it is needed. The receiver requests information, and the device pulls up radio resources at that moment, and then again is in an idle state until it starts receiving the requested information. Radio bands are allocated dynamically, depending on the type of content - several or even more at the same time, depending on whether a text message or live video is being transmitted. When a user turns on a device that supports GPRS, it usually automatically searches for a GPRS channel in the area. If a matching channel is found, the device will attempt to connect to the network. GPRS network The GPRS network is an overlay network that sits on top of GSM infrastructures. Key components of a GPRS network include:
When a GPRS user makes a call, the GPRS device contacts the GSM station, which in turn calls the SGSN, which communicates with other SGSNs or GGSNs if it needs to access another kind of network (IP or X.25). For the GPRS user, the connection is "seamless", there is no "call establishment" procedure. The GPRS technology, overlaid on top of the GSM network, was originally designed to dynamically and individually allocate GSM radio resources "per packet", as needed. If many GPRS users connect to a GSM cell at the same time, and the GSM cell is unable to support such a volume of voice traffic, the GPRS station will use the radio resources of neighboring GSM cells. Thus, in reality, GPRS users are served by many GSM cells at the same time when the need arises. So, the SGSN receives the connection request, requests the user profile information from the HLR node, and authenticates the user. At this point, encryption can be performed. The SGSN uses the profile information (including the access point name, which identifies the network and operator) to determine which GGSN to route to. The selected gateway can provide Remote Authentication Dial-In User Service (RADIUS) and assign a dynamic Internet Protocol (IP) address to the user before setting up connections to external networks. This process is called "Batch Data Profile Contextual Activation" and settings may vary from operator to operator. It may include additional features such as QoS (Quality of Service) management and virtual private network (VPN) management. When a mobile device is turned off or out of GPRS coverage, its context is deactivated and the device disconnects from the network. When a mobile user sends data, the SGSN forwards the packets to the corresponding GGSN. The GGSN then forwards the data according to the current "context" established for that session. In the reverse direction, packets destined for the user are directed to the GGSN associated with the user's IP address. The GGSN examines the received packets according to the current context, identifies the SGSN serving this user, and directs traffic in the appropriate direction. The SGSN then forwards the packets to the base station where the user is located. Benefits of GPRS GPRS provides higher data rates, always-on, connection stability, broad application support, and strong security mechanisms. Increasing the data rate GPRS currently supports average data rates in the order of 115 kbps, but these rates are only achieved when all eight timeslots (time slots) for GPRS are used. Instead, media and end devices will be typically configured to operate with a certain number of time slots for data sent in both directions. For example, a GPRS device can be configured to operate with a maximum of four slots in the forward direction and two slots in the reverse direction. In good radio conditions, this gives speeds of approximately 50 kbps in the forward direction and 20 kbps in the return direction. This is more than three times faster than current GSM networks (14.4 kbps) and on the same order of magnitude as a good analog cable modem connection. The total cell site bandwidth is divided between voice traffic and data traffic. GPRS operators use this bandwidth differently. They typically configure networks to prioritize voice traffic; some of them allocate time slots for data traffic in order to guarantee a minimum level of this service during periods of high voice traffic. Unused capacity reserved for voice traffic can be dynamically re-allocated to data. With higher data rates, GPRS enables applications that require higher bandwidth and are currently not feasible on GSM networks. Permanent connection A persistent connection - "always online" - eliminates the time delays associated with a dial-up connection, associated with establishing a new connection to the network each time data needs to be sent and received. Information can be transmitted to the end user in real time. GPRS allows providers to perform billing accounting on a per-packet basis rather than per-minute basis, thus enabling users to provide more cost-effective services. Connection stability GPRS has improved the integrity of data transmission through the application of a number of mechanisms. First, the user data is encoded with some redundancy, which improves its resistance to adverse radio conditions. The level of redundancy in coding can vary, depending on the same radio conditions. GPRS defines four coding schemes, CS1 to CS4. Initially, only CS1 and CS2 are supported, which provide approximately 9 and 13 kbps per time slot. If an error in the BSS is detected in a received frame, this frame is periodically repeated until it is received in acceptable quality before being transmitted to the GPRS core network. Broad application support Like the Internet, GPRS is based on packet data switching. This means that all native IP applications can be implemented within GPRS such as e-mail, Web access, instant messaging and file transfer. In addition, its higher data rates enable GPRS to handle applications that require more bandwidth (such as multimedia web content) that do not run on slower GSM dial-up connections. GPRS is more or less well suited for applications based on the Wireless Application Protocol (WAP). WAP has become widespread in the new generation of mobile phones that support microbrowsers. Security GPRS builds on the proven authentication and authorization model used by GSM. When a session is initiated, the user is authenticated using secret information contained on a smart card called a Subscriber Identity Module (SIM). The authentication data is sent to the HLR network node and validated there. GPRS allows additional authentication through the use of protocols such as RADIUS before subscribers are allowed access to the Internet or corporate data network. GPRS supports encryption of user data when transmitted over a wireless interface from a mobile terminal to the SGSN. In addition, there may be high-level end-to-end VPN (Virtual Private Network) encryption when a user connects to a private corporate network. So, if we divide these benefits into those that relate to users and service providers, we get the following picture: For service providers: • New market and increased profits as we transition to offering new multimedia and content services to customers.
For clients: • QoS services become available as a salable product. Now that GPRS technology has introduced the first packet-switched application for mobile subscribers, service providers can use conventional technologies to deploy service applications in traditional IP networks.
GPRS restrictions It is already quite clear that GPRS is an important new service for mobile devices, not only enabling data transmission, but significantly improving spectral efficiency, capacity and functionality compared to non-voice mobile services used so far. However, it is important to note that GPRS also has some limitations, which are described below: Limited cell capacity GPRS has a significant impact on the existing cell network capacity. The amount of available radio resources that can be used for different purposes is limited, and the use of resources for one purpose precludes their simultaneous use for others. For example, both voice calls and GPRS sessions use the same network resources. The perceived impact depends on the number of timeslots reserved for GPRS exclusive use, if any. However, in reality, GPRS dynamically manages the assignment of channels and allows you to reduce the load on the signal channel at peak times by sending short messages over GPRS channels. Result: The need for SMS as an additional carrier using a different type of radio resource. Real speeds are much lower Achieving the theoretical maximum GPRS data rate of 172.2 kbps would require an individual user to use all eight timeslots without any error protection. It is clear that in practice it is quite unlikely that a network operator would allow all slots to be used by a single GPRS user. In addition, the "first generation" GPRS-terminals are strictly limited to support only one, two or three timeslots. Therefore, the bandwidth available to the GPRS user is also strictly limited. For this reason, the theoretical maximum GPRS speeds cannot be achieved in real networks and real terminals. The reality is that mobile networks will probably always have lower data rates than fixed networks. Result: Relatively high data rates through mobile devices may not be available to individual users of mobile services until significant speed improvements are available on GSM Evolution (EDGE) or Universal Mobile Telephone System (3GSM) networks. Sub-optimal modulation GPRS is based on a modulation technology known as GMSK (Gaussian minimum-shift keying). EDGE networks are based on a new modulation scheme that allows much higher data rates over the air interface - this is called 8 PSK (eight-phase-shift keying) modulation. Since 8 PSK will also be used in 3GSM, network operators will need to take this into account at some stage in their transition to XNUMXG mobile networks. Result: The need for EDGE. Transmission delays GPRS packets are sent in all directions to eventually reach the same destination. This creates the risk that one or more of these packets will be lost or corrupted during data transmission over the radio. GPRS standards take into account this inherent property of wireless packet technologies, laying in their strategies the tasks of maintaining data integrity and retransmission. However, transmission delays may occur as a result of this insurance. As a result, applications that require high quality video transmission can perform well when using HSCSD (High Speed Circuit Switched Data). HSCSD is simply data circuit switching where an individual user can use up to four different channels at the same time. Due to the principle of end-to-end communication between sender and receiver, transmission delays are less likely. Result: Need for HSCSD. Where is GPRS applied? Non-voice mobile services such as SMS and GPRS underpin a wide range of enterprise and consumer applications. This section describes those that are directly related to GPRS. In the past decades, mobile applications like GPRS were used exclusively by military, medical, government and transportation organizations, but there were no standards or providers to widely disseminate these technologies to make them available to ordinary people. And only relatively recently, subscribers began to use GPRS with ever-increasing activity, since the technology has become much cheaper and more accessible. In addition, mobile system subscribers have always wanted to be able to use the same applications they use when they work on personal computers. There have been many attempts, using various technologies, to offer mobile users the same experience as the Internet using existing technologies, but the problem was to minimize all content, and also transform it in such a way as to make its compatible with the parameters of the device and the band used. With the constant miniaturization of electronics, many new mobile devices are becoming faster, more efficient and more like personal computers. With the improvement of the hardware, many applications will be offered. Home applications are very important, but business applications look set to make a real breakthrough in this technology. Many analysts warn that by 2002-2003 almost half of daily business transactions will be possible using mobile devices. • Text - Text applications for the new generation of mobile devices will be significantly different from their predecessors. Because the devices will operate using IP, they will not need special messaging systems. The user will be able to use any existing internet messaging system (ICQ, MSN, AOL...etc.). And the chances are that even if service providers decide not to create a unified messaging system, users will be able to use existing freeware (eg Trillium) to do so. Users have the opportunity to receive a wide range of content on their mobile phones - stock quotes, sports scores, weather information about flights, news headlines, reminders, lottery results, jokes, horoscopes, traffic information, local services and the like. This information does not have to be purely textual - it can also be maps, graphs, or other types of visual information. A 160-character short message is long enough to convey "quantitative" information such as stock prices, sports scores, or the weather. However, when the information is of a qualitative nature, such as horoscopes or news, 160 characters are not enough for anything other than pique the interest or annoy the recipient of the information. For this reason, GPRS is most likely to be used for information services built on "qualitative" information for end users with devices that support GPRS, while SMS will continue to be used to send most of the "quantitative" information. Interestingly, chat applications are a form of "quality" information that can be retained via SMS to achieve brevity and reduce irrelevant messages. Pictures With the increasing resolution of mobile device displays, it is becoming more and more practical to send full-color photos, postcards and presentations. But until quite recently, users had the opportunity to contemplate on the screens of mobile phones only black-and-green images, which could only be viewed from a certain angle and guess what could be depicted there. Still images such as photos, pictures, postcards, greetings and presentations, as well as still web pages can be sent and received over the mobile network. Using GPRS, you can send images from a digital camera connected via a GPRS radio directly to Internet sites. Sound New devices will be able to use not only new audio capabilities, but also audio transmission services over the Internet. Devices can also be configured to send and receive audio snippets in real time. And there is no doubt that over time, the voice command interface will be available for any simple commands. This kind of technology is already available today in the most expensive cars and the most advanced cell phones. GPS and road map services are also very attractive services for users today. In Japan, almost all cars are equipped with the standard option for a DVD GPS system. Despite numerous attempts to improve the quality of voice communication in mobile networks, such as Enhanced Full Rate (EFR), they still do not provide the required quality. There are a number of common practice situations, such as journalists or police situations, where it is necessary to capture conversations with people or radio messages using professional quality handheld microphones and send this information to a radio station or police station. Simply leaving the mobile phone switched on or dictating the necessary information to the mobile phone will not provide sufficient sound quality for voice analysis and dubbing when accurate voice identification is important. Since even short voice fragments take up a significant amount of space in the form of files, GPRS or other high-speed mobile data services are essential in such cases. Video As well as with audio transmission, users have the opportunity to work with live video. As storage devices, processors are becoming smaller and access speeds are increasing, which is essential when using cell phones for videoconferencing, which will soon become a daily practice. Moreover, watching TV programs will soon be possible not only with the help of TVs, but also through mobile devices. Over time, the nature and form of mobile communications is becoming less textual and more visual. The wireless industry is moving from text messaging, to icon and picture messaging, to sending photos and drawings, to video messaging and movies that can be downloaded and viewed in their entirety via a mobile device. The transfer of moving images through the mobile medium also finds applications in related market niches. For example, this applies to monitoring parking lots or monitoring homes in the absence of owners - against random guests or thieves, when the system, if triggered, can send an image of what is happening to the owner. Video conferencing applications can also be in high demand, where, for example, distribution teams can hold their regular sales meetings without having to meet at a dedicated "physical" meeting point - this is another moving image application. Internet Until recently, the technologies used by mobile devices were limited by the capabilities of mobile devices themselves. With advances in mobile communications and electronics, mobile phones are becoming more and more like computers. Thus, most PC functions become available on mobile devices as well. Features such as email, newsgroups, interactive web chat will be available regardless of the user's location. These services can be used in cars, at home, in offices, on the street. Using Circuit Switched Data to search and browse the web has never supported applications for mobile users. Due to the slow transfer rates of Circuit Switched Data, it takes too long for the data to be transferred from the Internet server to the browser. Alternatively, users turn off images and display only text, having difficulty reading text pages on the screen. For this reason, searching and browsing the web is much better suited to work with GPRS. Chat Chat can be separated from the main information services, since the source of information in this case is the person with whom the conversation is being conducted, while usually the information services are "consumed" from Internet sites. "Information intensity" - the amount of information transmitted per unit of message - is usually lower in chat because it has a different task: people in chat are more likely to express their opinions than to report factual data. Just as on the Internet, where chat groups are a very popular Internet application, groups of like-minded people - the so-called interest societies - are increasingly starting to use non-voice mobile services as tools for communication and discussion. "Joint activity" GPRS with the Internet allows mobile users to fully participate in Internet chats, without the need to create any separate groups designed specifically for mobile users. Since the number of participants is an important factor in determining newsgroup participation, the use of GPRS would be preferable here. However, GPRS does not support point-to-multipoint services in its first phase, which makes it difficult to send a single message to a group of people. For this reason, SMS is expected to remain important for chat applications for the foreseeable future, although GPRS adoption can be expected sooner rather than later. Document Sharing/Collaboration Mobile data transfer facilitates document sharing and remote collaboration. This allows different people in different locations to work on the same documents at the same time. Even multimedia applications can be envisaged containing both voices, text, pictures and images. These types of applications can be useful in solving problems in various fields such as firefighting, medicine, advertising, architecture, journalism, and so on. Even the decision about which resort to book a ticket to can be made remotely if it is possible, together with the manager of the travel agency, to view the necessary prospectuses and documents with comments, without the need to visit the travel agency physically. Being anywhere, a person may have the advantage of being able to comment on the visual images viewed together, concerning an issue on which joint work can be useful. By providing sufficient bandwidth, GPRS facilitates multimedia applications such as document sharing. Communication during assignments It is quite common that employees of a company providing services spend most of their time "in the field", performing certain tasks. Non-voice mobile services can be used to assign new tasks and communicate in terms of their implementation - between employees who are constantly in the office and mobile "field" employees. Typically, company customers call the office (call center), whose staff receives the call and considers it. Their calls require a visit from a "field" employee of the company. Job submission applications can optionally be combined with vehicle location applications to determine the closest employee to a destination that can be sent to service a customer. GSM non-voice services can be used not only for job forwarding, but also as a tool for field engineers or salespeople to keep their office informed of the progress of certain tasks at all times. A remote worker can send a status message like "Task 1234 completed, working on 1235". A 160 character short message is sufficient for most of the communications required for sales, services, or any other job assignment applications, such as ordering pizza on a cell phone and ordering a courier. However, 160 characters requires certain tricks in order to be able to fit customer data into this volume, i.e. will inevitably have to use abbreviations. Those 160 characters don't leave much space for giving the field worker any information about the issue being asked about or a detailed description of the client. Traveling representatives of the company have the opportunity to arrive at the client, but apart from this they are provided with almost no information. This is where GPRS comes into play, allowing much better informing of the employee as it is very easy to both send and receive a significant amount of information. Using GPRS, for example, you can send a photo of the client and his home to an employee to help him find and identify the client. With all these advantages, job assignment applications are expected to emerge first among GPRS-based communications applications. Corporate email With up to half of a company's employees spending some time out of the office, it's important for them to stay in touch with the office by extending the use of corporate e-mail systems beyond office PCs. Corporate email systems run on computers on the internal network (LAN) and include applications such as Microsoft Mail, Outlook, Outlook Express, Microsoft Exchange, Lotus Notes, and Lotus cc:Mail. Because GPRS-enabled devices are more common in corporations than among individual mobile phone users, it is likely that there will be a larger market for corporate email applications using GPRS than for Internet email applications. Email over the Internet Internet e-mail services take the form of gateway services, where messages are not stored, or mailbox services, where messages are stored. In the case of gateway services, the wireless email platform simply translates the message from SMTP, the Internet Protocol for Email, into SMS and sends it to the SMS center. In the case of mailbox email services, messages are stored and the user receives a notification on their mobile phone and can then read the message as it is, forward it, and so on. After receiving a new letter, most users of Internet e-mail services do not receive a notification on their mobile phone about this fact. When they are out of the office, they have to periodically join the mailbox if they are waiting for a letter. However, by associating Internet email with an alert mechanism such as SMS or GPRS, users can be notified when a new email arrives. Vehicle Location This application integrates satellite positioning systems that give people information about where they are using non-voice mobile services. The Global Positioning System (GPS) is a free-to-use global network of 24 satellites maintained by the US Department of Defense. Anyone with a GPS receiver can receive information about their location from the satellite and thus understand where they are. Vehicle location applications can be used to provide several services, including remote vehicle health diagnostics, location of stolen vehicles, and notification of new rental car rates. Short Message Service (SMS) is ideal for sending position information such as longitude, latitude, azimuth and altitude from the Global Positioning System (GPS). GPS-determined coordinates are typically on the order of 60 characters long in the record. Alternatively, GPRS can be used. Remote LAN access It is already obvious to everyone that mobile devices are turning into miniature personal computers, so everyone has already become accustomed to the fact that they are capable or will be able to support most of the applications supported by personal computers. Another attractive feature of corporate mobile devices will be VPNs. Currently, they are intensively developing and becoming extremely popular among users of mobile services. File sharing, creating user zones, querying databases, personalized login, collaboration, integration with other devices, and many other features of a conventional personal computer are likely to be offered for widespread use by mobile users. When employees whose work involves frequent movement are not at their desks in the office, it is vital for them to be connected to the internal network (Local Area Network) of the company. Remote LAN applications access any applications an employee would use while sitting at their desk, such as intranet access, corporate email services such as Microsoft Exchange or Lotus Notes, and database applications running on Oracle, Sybase or any other environment. A mobile terminal, such as a PDA or laptop, has the same software as the personal computer on the employee's desk, or stripped-down versions of the applications are available through the corporate LAN. For this reason, this application area is most likely to become a conglomeration of remote access to several different types of information - such as email, intranet, databases. All of this information may be accessible through web browsing tools, or may still require appropriate software applications for mobile devices. The ideal tool for remote LAN access depends on the amount of data that needs to be sent, but GPRS's speed and latency make it the perfect tool. File transfer As this generic term suggests, file transfer applications perform any form of large data download over the mobile network. Such data could be presentation documents for a travel agency manager, a device description for a service engineer, or a software application such as Adobe Acrobat Reader to read the documents. The source of this information may be one of the Internet communication methods such as FTP (File Transfer Protocol), telnet, http or Java - or their own database or operating platform. Regardless of the source and type of file to be transferred, this type of application requires a lot of bandwidth. Therefore, high-speed mobile data services such as GPRS, EDGE or 3GSM are vital in order to satisfactorily perform this kind of task. home automation The power of mobile devices can be greatly enhanced for both personal and business needs with compact and simple functions in home and business applications. For example, a critical feature is the integration of signaling devices into mobile phones. Anything from a home fire alert to email notification can be instantly communicated to a mobile phone user. In home automation applications, remote security is combined with remote control. Basically, you can watch your home from anywhere, wherever you are - on the road, on vacation or in the office. If your burglar alarm goes off, you will not only be alerted, you will also be able to see exactly who is trying to break into your home and maybe even lock them inside. That is, you can not only see what is happening in your house, but also perform some actions in the house. You can remotely turn on your VCR to record a TV program, turn on the stove to warm up dinner when you arrive home, and the like. Your GPRS-equipped mobile phone actually acts like a remote control, like the ones we use daily for our TV, VCR, hi-fi, etc., but at a much greater distance. Since Internet Protocol (IP) will soon be in all devices - not just GPRS-equipped mobile phones, but in all types of household appliances and in every device - these devices can be accessed and given instructions. A key tool for home automation will be Bluetooth, which allows you to network and interact with various incompatible devices. 3G networks A direct consequence of the evolution of GSM/GPRS services is the creation of UMTS (Universal Mobile Telecommunications System). This is the next step from GPRS towards a real third generation (3G) mobile network. It is a broadband technology based on packet transmission at data rates up to 2 Mbps indoors and 348 kbps outdoors. UMTS will offer a compatible (consecutive) set of services to mobile network customers, no matter where they are. UMTS, based on the GSM communication standard, is supported by all leading manufacturers. These plans were implemented during 2002. Mobile service users will have access to both wireless and satellite signal transmission. EMR spectrum for UMTS has been tentatively allocated to 1885 - 2025 MHz for future IMT-2000 systems, and 1980 - 2010 MHz and 2170 - 2200 MHz for the satellite division of UMTS systems. The most convenient candidate so far for the transition to 3G is WCDMA (Wide Band Code Division Multi Access). Simply put, WCDMA is the basis of a wireless transmission technology that uses a unique user code to encode channels. The channels do not use separate channel bands, but share a 5 MHz bandwidth, giving them incredible bandwidth. GPRS technology represents the first significant step towards a new era of communication - anytime, anywhere. The next step after GPRS for the mobile industry will be to focus directly on building 3G networks based on 2.5G networks, which will eventually provide higher capacity and data speeds, as well as support new multimedia services. Key 3G technologies include: Enhanced Data Rates for GPRS Evolution (EDGE) Systems Increasing data rates for the GPRS network to approximately 384 kbps per channel. Wideband CDMA (WCDMA) Uses a 5 MHz CDMA radio channel to support theoretical data rates up to 2 Mbps. WCDMA is expected to become the dominant standard in the transition to 3G networks and will be deployed worldwide in conjunction with GSM/GPRS networks. cdma2000 Supports higher data rates of 3G, a version called 1xEV is introduced, which enables speeds of 2.4 Mbps and is likely to be rolled out in the US and several Asian countries. Large-scale deployment of these networks is expected to take place over the next few years. So, GPRS technology has brought many benefits to the mobile industry, making Internet access from mobile devices more convenient due to the high data transfer rate and the fact that GPRS devices provide functions similar to those provided by personal computers. This makes it easier for service providers to implement these services and expands Internet access services from mobile devices equipped with a GPRS module and facilitates integration with older mobile cellular technologies. GPRS is clearly not a 3G protocol, but this technology in itself is an important milestone and the next evolutionary step towards 3G. Around the same time that the first 3G devices become available, there will be an evolution not only in technology, but also in how people think about technology. In the very near future, mobile devices will become much more useful for people and will significantly improve every day of our lives. Many grimly prophesy that technology will conquer us, but as the reality shows, in fact, so far, technology has set us free. Publication: cxem.net
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