Mobile networks, also called cellular networks, are based on different kinds of multiple access schemes in their radio interface (communication between mobile station and base station). Traditional multiple access schemes, such as Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), and Code Division Multiple Access (CDMA) are utilized in first-generation (1G) and second-generation (2G) systems. Mobile TechnologyAnalog FDMA-based networks, such as Advanced Mobile Phone Service (AMPS), Nordic Mobile Telephone (NMT), and Personal Handy phone System (PHS), are called first-generation systems. The first digital mobile networks, such as North American TDMA (also known as D-AMPS because of the same frequency band used), and cdmaOne, European Global System for Mobile communications (GSM), and Japanese Personal Digital Cellular telecommunication system (PDC) are called second-generation (2G) systems. Enhancements of 2G systems, such as packet transmission - General Packet Radio System (GPRS) and Enhanced Data calls for GSM Evolution (EDGE) - are usually referred to as 2.5G. In specification work, the International Telecommunication Union (ITU) defines the common name IMT-2000 for 3G systems, and the third generation partnership project, 3GPP, takes care of standardization work for the entire mobile network family - GSM (2G), GPRS (2.5G), EDGE (2.5G) and UMTS (3G). 
Universal Mobile Telecommunication SystemUMTS as a system is an evolutionary step for voice and data calls of different transmission rates measured in kbps or Mbps. The key idea of UMTS is to be as dynamic as possible and to use system resources for different purposes (for example FACH or RACH channels for both signaling and low data traffic needs). Voice calls range from low quality to high quality (6-12 kbps, for example), depending on the user profile. Data services also vary (from 0 kbps to 2 Mbps), depending on the application needs. Various data applications like video streaming and games are aggressively marketed, even though the applications most expected today are email and Multimedia Messaging Service (MMS) solutions, and the major goal of UMTS is the reduction of response time in these data transmission applications. The UMTS network contains Radio Access Network (RAN), Core Network (CN), and Network Management System (NMS). Radio access network is also called UMTS Terrestrial RAN (UTRAN), and radio access (radio interface) is also called UMTS Terrestrial Radio Access (UTRA). GSM is also part of the UMTS network; thus the UMTS system has similar types of interfaces and network elements as in GSM. Due to similar architecture, the UMTS part of the specification is similar to the GSM part of the specification (for example, in the names and use of signaling channels or radio interface parameters); therefore, a good knowledge of the GSM is very helpful in understanding the UMTS system. Digital DividendThe latest development in mobile technologies is LTE (Long Term Evolution) technology which will be mainly used in frequency bands which were released after the transition to digital TV broadcasting - digital dividend. 3GPP Long Term Evolution is the latest standard in the mobile network technology tree that produced the GSM/EDGE and UMTS/HSPA network technologies. It is a project of the 3rd Generation Partnership Project (3GPP), operating under a name trademarked by one of the associations within the partnership, the European Telecommunications Standards Institute. The LTE specification provides downlink peak rates of at least 100 Mbps, an uplink of at least 50 Mbps and RAN round-trip times of less than 10 ms. LTE supports scalable carrier bandwidths, from 1.4 MHz to 20 MHz and supports both frequency division duplexing (FDD) and time division duplexing (TDD). 
The mobile industry is seeking an allocation of at least 100 MHz of Digital Dividend spectrum in all regions, awarded on a harmonized basis. With such an allocation, the vision of mobile broadband everywhere can be transformed into a reality. Spectrum (or frequency) harmonization, where countries across a region use the same spectrum frequency, is vital. It is critical for the successful, cost-effective deployment of any wireless service as it provides the economies of scale which drive down handset and network equipment costs and encourage innovation. Without such harmonization, handset costs could be prohibitively high, which would reduce uptake. This would harm not only consumers and the mobile industry, but also reduce the benefits that mobile technologies bring to national economies. If spectrum allocation is not coordinated internationally, then many smaller markets may be neglected by device manufacturers, who would naturally concentrate on larger markets, with greater potential for volume sales and a higher return on investment.
Universal Mobile Telecommunication SystemUMTS as a system is an evolutionary step for voice and data calls of different transmission rates measured in kbps or Mbps. The key idea of UMTS is to be as dynamic as possible and to use system resources for different purposes (for example FACH or RACH channels for both signaling and low data traffic needs). Voice calls range from low quality to high quality (6-12 kbps, for example), depending on the user profile. Data services also vary (from 0 kbps to 2 Mbps), depending on the application needs. Various data applications like video streaming and games are aggressively marketed, even though the applications most expected today are email and Multimedia Messaging Service (MMS) solutions, and the major goal of UMTS is the reduction of response time in these data transmission applications. The UMTS network contains Radio Access Network (RAN), Core Network (CN), and Network Management System (NMS). Radio access network is also called UMTS Terrestrial RAN (UTRAN), and radio access (radio interface) is also called UMTS Terrestrial Radio Access (UTRA). GSM is also part of the UMTS network; thus the UMTS system has similar types of interfaces and network elements as in GSM. Due to similar architecture, the UMTS part of the specification is similar to the GSM part of the specification (for example, in the names and use of signaling channels or radio interface parameters); therefore, a good knowledge of the GSM is very helpful in understanding the UMTS system. Digital DividendThe latest development in mobile technologies is LTE (Long Term Evolution) technology which will be mainly used in frequency bands which were released after the transition to digital TV broadcasting - digital dividend. 3GPP Long Term Evolution is the latest standard in the mobile network technology tree that produced the GSM/EDGE and UMTS/HSPA network technologies. It is a project of the 3rd Generation Partnership Project (3GPP), operating under a name trademarked by one of the associations within the partnership, the European Telecommunications Standards Institute. The LTE specification provides downlink peak rates of at least 100 Mbps, an uplink of at least 50 Mbps and RAN round-trip times of less than 10 ms. LTE supports scalable carrier bandwidths, from 1.4 MHz to 20 MHz and supports both frequency division duplexing (FDD) and time division duplexing (TDD).
The mobile industry is seeking an allocation of at least 100 MHz of Digital Dividend spectrum in all regions, awarded on a harmonized basis. With such an allocation, the vision of mobile broadband everywhere can be transformed into a reality. Spectrum (or frequency) harmonization, where countries across a region use the same spectrum frequency, is vital. It is critical for the successful, cost-effective deployment of any wireless service as it provides the economies of scale which drive down handset and network equipment costs and encourage innovation. Without such harmonization, handset costs could be prohibitively high, which would reduce uptake. This would harm not only consumers and the mobile industry, but also reduce the benefits that mobile technologies bring to national economies. If spectrum allocation is not coordinated internationally, then many smaller markets may be neglected by device manufacturers, who would naturally concentrate on larger markets, with greater potential for volume sales and a higher return on investment.
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