Universal Radio Carrier Fixed Loop
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ABSTRACT The business of wireless selective information is expected to grow in the region of 100-200 % per annum and the mobile communicating industry agrees that wireless info services will form the foundation for future business. The enormous success of short messaging in a lot of countries proves that humans receive the gains of non-voice services. Enhanced Data Rate for Global Evolution (EDGE) is a technology that gives Global Systems for Mobile Communications (GSM) the capacity to handle services for the third generation of mobile telephony. It provides three times the info capacity of General packet Radio Service (GPRS). Using EDGE, operators may handle three times more subscribers than GPRS; triple their info rate per subscriber, or add extra capacity to their voice communications. This article provides an overview of EDGE technology. In particular, starting from the introduction of this 2.5G engineering I describe the core technical distinct elements and distinct features. I will provide a comparison with GPRS for selective information services and then a survey of the current state of this technology in Pakistan. I have also covered galore gains for operators and customers. 1. Introduction The importance of wireless info and multimedia services both for business and end clients are increasing on an unparalleled scale. Enhanced Data Rates for GSM Evolution (EDGE) is a new radio interface solution and is based on an heightened modulation. EDGE offers GSM network operators an evolution path to mobile selective information and multimedia services with a three fold increase of data throughput in the existent GSM spectrum. EDGE hence provides an substitute for operators who do not have a Universal Mobile Telecommunication System (UMTS) license. Moreover it likewise represents a supplement to UMTS for operators intending to introductory deploy UMTS only in densely populated areas, but who may likewise use EDGE to provide wide area coverage of future oriented 3G services. In the US market operators have chosen EDGE as the 3G solutions. [8]. We are presently experiencing the Wireless Application Protocol (WAP) as well as the higher transmission speeds of High Speed Circuit Switched Data (HSCSD), joined by the comfortableness of “always on-line” direct Internet connections with GPRS. [1] EDGE, new radios interface engineering with intensified modulation, increments the HSCSD and GPRS selective information rates by up to three fold. EDGE modulation is going to increase the selective information throughput provided by the packet swopped service even over 400 kbps per carrier. Similarly, the data rates of circuit swapped data may be increased, or existent info rates may be achieved using less timeslots, saving capacity. Accordingly, these higher speed selective information services are referred to as EGPRS (Enhanced GPRS) and ECSD (Enhanced Circuit Switched Data). EDGE, is a major betterment in GSM phase 2+. As a modification to existent GSM networks, EDGE does not require new network elements. [1] In the US, for instance, EDGE is percentage of the IS-136 High Speed concept, which is one of the third generation Radio Transmission Technology (RTT) proposals from TR.45. EDGE is ultimately going to be standardized which makes possible to achieve a global mobile radio scheme with a lot of services characteristic to third generation systems. 2. Overview The increased bit rates of EDGE put necessaries on the GSM/GPRS network architecture. Figure. 1 illustrates the GSM/GPRS architecture, the shaded constituents of which are discussed in this section. Other nodes and interfaces are not affected at all by EDGE introduction. An evident bottleneck is the A-bis interface, which today supports up to 16 kb/s per traffic channel. With EDGE, the bit rate per traffic channel will approach 64 kb/s, which makes percentage of multiple A-bis slots to one traffic channel necessary. Alternative asynchronous transfer mode (ATM) or IP-based solutions to this problem may also be discusses. One crucial fact is, however, that the 16 kb/s limit will be exceeded already by the introduction of two coding systems (CS3 and CS4) in GPRS, which have a maximal bit rate per traffic channel of 22.8 kb/s. Consequently, the A-bis limitation problem is being solved outside the EDGE standardization, and it is accordingly a GPRS related, not EDGE-related, modification. For GPRS-based packet data services, other nodes and interfaces are already competent of handling higher bit rates, and are therefore not affected. For circuit-switched services, the A interface may handle 64 kb/s per user, which is not exceeded by EDGE circuit-switched bearers. [9] 2.1. Impact on GSM Network Planning An necessary prerequisite, which to a big extent will determine the success of EDGE in GSM, is that a network operator be capable to introduce EDGE gradually. For initial deployment, EDGE-capable transceivers will supplement frequent GSM/GPRS transceivers in a subset of the existent cells where EDGE coverage is desired. Hence, an integrated mix of GSM, GPRS, and EDGE users will coexist in the same frequency band. To minimize effort and cost for the network operator, radio network planning (including cell planning, frequency setting of power and other cell parameters) ought to not require broad modification. 2.1.1. Coverage Planning One characteristic of non-transparent radio link protocols that include automatic repeat request (ARQ), is that low radio link quality only results in a lower bit rate for the user. Hence, low SIR for a user does not result in a dropped call, as for speech, but in a temporary decrease of user bit rate. For transparent bearers, which distinctively offer a continuous bit rate, link quality control will have to be extended to comprise resource allocation, in the sense that the number of dynamically allocated time slots fits the bit rate and bit error rate (BER) retirements. Transparent bearers, will therefore be available in the entire GSM cell, but require less time slots in the center of the cell (where 8-PSK coding schemes may be used). 2.1.2. Frequency Planning Most mature GSM networks of today have an intermediate frequency reuse element of around 9 (meaning that available frequencies are separated into nine frequency groups). However, there is also a trend toward tighter reuse factors. With the use of frequency hopping, multiple reuse patterns (MRP), and discontinuous transmission (DTX), reuse constituents as low as 3 become feasible. EDGE supports a potpourri of reuse patterns. In fact, by it is use of link quality control, EDGE may be introduced in an arbitrary frequency plan, and gain from high SIR closer to the base stations. EDGE may be introduced in an existent GSM frequency plan, and that it also supports future high-capacity solutions based on tighter frequency reuse. 2.1.3. Radio Network Planning An essential prerequisite (and to a big extent, one that will determine the success of Edge) is that network operators ought to be capable to introduce Edge gradually. The introductory deployment of Edge-capable transceivers will supplement general GSM transceivers in a subset of cells where Edge coverage is desired. An integrated mixture of circuit-switched, GPRS and Edge users will thence coexist in the same frequency band. To minimize operator attempts and costs, Edge-related implementation ought to not require spacious modification of the radio network plan (including cell planning, frequency planning, the setting of power levels and other cell parameters). 2.1.4. Channel Management After Edge has been introduced, a cell will quintessentially include two types of transceiver: general GSM transceivers and Edge transceivers. Each physical channel (time slot) in the cell may be viewed as being one of at least four channel types: 1. GSM speech and GSM circuit-switched data (CSD); 2. GPRS packet data; 3. Circuit-switched data, heightened circuits witched data (ECSD), and GSM speech; 4. Edge packet data (EGPRS), which allows a mix of GPRS and EGPRS users simultaneously. While usual GSM transceivers only aid channel types 1 and 2, Edge transceivers support all four channel types. Physical channels are dynamically specified according to terminal capablenesses and needs in the cell. For example, if assorted speech users are active, the number of type-1 channels is increased, at the expense of GPRS and Edge channels. Obviously, channel management will have to be automated, to stay clear from the splitting of channels into static groups. Otherwise, trunking efficacy would diminish. 3. Interleaving To increase the performance of the higher coding schemes in EGPRS (MCS7 to MCS9) even at low C/I, the interleaving routine has been changed within the EGPRS standard. When frequency hopping is used, the radio environs is altering on a per-burst level. Because a radio block is interleaved and transmitted over four bursts for GPRS, each burst may experience a completely dissimilar interference environment. [7] If just one of the four bursts is not the right way received, the entire radio block will not be the right way decoded and will have to be retransmitted. In the case of CS4 for GPRS, scarcely any error shelter is applied at all. With EGPRS, the frequent handles the higher coding system differently than GPRS to combat this problem. MCS7, MCS8 and MCS9 genuinely transmit two radio blocks over the four bursts, and the interleaving occurs over two bursts rather of four. This reduces the number of bursts that ought to be retransmitted must faults occur. The likelihood of receiving two successive error free bursts is higher than receiving four successive error free bursts. This means that the higher coding schemes 4. EDGE & GPRS EDGE, or the Enhanced Data Rate for Global Evolution, is the new mantra in the Global Internet Connectivity scene. EDGE is the new name for GSM 384. The engineering was named GSM 384 because of the fact that it provided Data Transmission at a rate of 384 Kbps. It comprises of the 8 pattern time slot, and the speed could be achieved when all the 8 time slots were used. The idea behind EDGE is to obtain even higher info rates on the current 200 KHz GSM carrier, by altering the type of the modulation used. Now, this is the most striking feature. EDGE, as being once a GSM technology, works on the existent GSM or the TDMA carriers, and enables them to a great deal of of the 3G services. Although EDGE will have a little technical impact, since it is to the full or entire extent based on GSM or the TDMA carriers, but it might just get an EDGE over the up coming technologies, and of course, the GPRS. With EDGE, the operators and service suppliers may offer more wireless data application, including wireless multimedia, e-mail (Web Based), Web Infotainment, and above all, the technology of Video Conferencing. Now all these technologies that were named earlier, were the clauses of the IMT-UMTS 3G Package. But, with EDGE, we may get all these 3G services on our existent GSM phones, which might just prove to be a boon to the user. Secondly, it allows the existent GSM or the TDMA carriers to give the sophisticated 3G services. And with 1600 Million subscribers of GSM in over 170 countries, offer the full Global Roaming, anyplace amongst India to Japan and to San Francisco. Based on an 8 PSK modulation, it allows higher bit rate all over the air Interface. There is one symbol for each 3 bits. Thus, EDGE Rate is equivalent to 3x GPRS Rate. 5. Future Evolution Towards WCDMA The next evolutionary step for the GSM/EDGE cellular scheme includes enhancements of service provisioning for the packet-switched domain with the service provisioning in UMTS/UTRAN (UMTS terrestrial radio access network). GERAN will provide bettered support for all quality of service (QoS) classes specified for UMTS: interactive, background, streaming and conversational. By doing so, a new range of applications, including IP multimedia applications, will be adequately supported. This part of the GSM/EDGE evolution focuses on help for the conversational and streaming service classes, because adequate help for interactional and background services already exists. Additionally, parallel simultaneous bearers will help multimedia apps with dissimilar QoS characteristics towards the same MS, such as multiple media streams handled through IMS domain. A driver for such evolution on the packet-switched side is the paradigm shift within the telecommunications world from circuit to packet-switched communications. Both the core network specified for GPRS and the current GSM/EDGE radio access network require modifications to support heightened packet services. The GPRS/EGPRS networks may speedily and cost efficaciously evolve with market needs, and align with services provided by WCDMA networks. The current evolution of GSM/EDGE, which covers all of the above aspects, is being standardized in 3GPP TSG GERAN. [4] 6. EDGE in Pakistan Pakistan has the sixth biggest population in the world – approximately 150 million. There are presently four mobile operators in the country. Mobile penetration at the end of 2003 was just 2.3% with a subscriber base of 3.4 million, while fixed line penetration was approximately 2.4%. Many geographic areas in Pakistan are without telephone coverage. To accompany recent positive economic development in Pakistan and the inherent low mobile penetration, high growth within the mobile segment is expected. At the moment the humans in Pakistan are more concern with the text-enabled facility like SMS. Although the introduction of GPRS gave a new conception and new boost in Cellular network but still, people are not that much concern using Internet by their terminal. Few think that it still more pricey and few believe that GPRS didn’t construct the interest for using Internet if we equated it by computer. In April 2004 Norwegian mobile telecom operator, Telenor, bid for and ultimately won a license to operate a cellular network in Pakistan. The license covers the operation of Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS) and Enhanced Data Rates for Global Evolution (EDGE) technology for the network. [14] Telenor Pakistan has signed two deals with mobile infrastructure contractors for dissimilar areas of the network: Nokia have signed a three-year deal to build and operate a GSM / GPRS / EDGE network to cover the central and Northern Punjab region (phase one), centered around Lahore. Siemens have signed a deal to build a GSM / GPRS / EDGE network to cover the southern areas of Pakistan, centered around Islamabad. Further enhancements in data capability over the core GPRS / GSM network will be provided in both networks with the installation of Enhanced Data for Global (GSM) Evolution technology. This factor of the two schemes will be installed after the initial roll-outs and will grant the subscribers to have the use of modern mobile services such as downloading video and music clips, full multimedia messaging, high-speed color Internet access and email on the move. Nortel Networks will upgrade Ufone’s existent wireless schemes and supply new GSM/GPRS core network and radio access equipment, including Mobile Switching Center, Home Location Register (HLR) and modern Base Transceiver Stations (BTS). A key element of the Ufone elaboration will be Nortel Networks BTS 12000, designed to deliver further and added capacity within a GSM/GPRS network while positioning operators to drive lower costs and to offer innovative wireless services based on third generation (3G) EDGE (Enhanced Data for GSM Evolution) technology. The elaboration will likewise include Nortel Networks Passport Packet Voice Gateway (PVG) for migration of TDM voice trunking to a packet-based infrastructure. 7. Benefits As highlighted antecedently the need to reduce business peril and make the best use of existent resources is of paramount importance within today’s business environment. 7.1. Financial GSM based networks have become the ordinary within the cellular landscape. As EDGE is a GSM based engineering science and provides an enhancement for GPRS at a little further and added cost it is considered the best way in which to capitalize on existent resources. [1] 7.1.1. Radio Access Network In most cases GPRS enabled base stations and BSC’s may be plainly upgraded to EDGE by way of comparatively low-cost software and hardware upgrades, which will pro-long the life cycle of the deployed RAN elements. 7.1.2. Core Network For GPRS enhancement, there is very little modification to be finished within a GPRS enabled core network, therefore heightening the sunk core network investment. 7.1.3. Antenna Sites There is no requirement for further and added antenna web sites when deploying EDGE. Assuming high quality linear amplifiers with high RF output power are used within the BTS, the coverage pattern will be the same as the existent GPRS deployment, so protecting existent website investment. 7.1.4. Spectrum Utilization EDGE triples the GPRS info capacity whilst using the existent GSM spectrum and offers up to three times the GPRS info rate to the end user. EDGE is spectrally the most effective radio engineering science for info apps necessitating up to 100Kb/s throughput (compared to CDMA and WCDMA), and only WCDMA is spectrally better for higher throughputs. 7.1.5. Applications GPRS enabled apps and services will in general not require any further and added investment to become EDGE compatible. This is also valid for known WCDMA applications. 7.2. For Operator Operators may likewise experiences the vantages of EDGE in following ways. 7.2.1. Migration to wireless multimedia services The operator may increase selective information revenues by providing beautiful new types apps to end-users. 7.2.2. Improved client satisfaction Increased selective information capacity and higher selective information throughput will decrease response times for all info services, thence keeping end users satisfied and connected. 7.2.3. Early deployment of 3G type applications EDGE networks are expected to emerge in year 2001, when mature markets are likely to start out demanding multimedia applications. 7.2.4. Quick network implementation EDGE will not require new network elements and EDGE capability may be introduced gradually to the network. 7.3. For User 7.3.1. Improved quality of service Increased info capacity and higher selective information throughput will finally satisfy the customers’ need for QoS. 7.3.2. Personal multimedia services Attractive new types of apps and terminals will become available. 7.3.3. Potentially lower price per bit Lower cost of data capacity for high-speed info apps gives the operator flexibleness in pricing. 8. Conclusion While the tug of war amidst access technologies – CDMA vs. UMTS vs. GSM — proceeds to be debated globally, EDGE provides an idealisti solution for GSM carriers to add info capacity using fixed spectrum. Keeping in view the fact that GSM supports more subscribers today than any other access technology (roughly 65 to 70% of the global subscriber market), and that GSM/GPRS operators are scrambling to add capacity to help user growth and launch next generation info services, the increased capacity and throughput offered by EDGE becomes very compelling. And, in a market where wireless carriers ought to squeeze the most out of capital outlays–past and future, it is no real surprise that we are going to see a renewed wave of interest in EDGE from our GSM customers. Today the position of EDGE as a engineering science evolution of GSM is clear. Initially promoted as an substitute to WCDMA and in general a niche technology, EDGE is now regarded as a key enabler for GSM/EDGE and WCDMA operators alike. Being capable to drive business value from existent GSM infrastructure and spectrum is one of the main advantages, and along-with the capacity of EDGE to reduce CAPEX, time-to-market and time-to-revenue, with regards the deliverance of international high-speed selective information services, EDGE is a must technology. The cellular companies working in Pakistan did not have the license for the EDGE. Now as the introduction of a good deal of new companies like Telenor and WARID, it is possible that in near future Pakistan will also be capable to use this facility. Then GPRS may become a real crucial factor in cellular network, as the humans in Pakistan will use the Internet not only for downloading ring tones but also may get enjoyment from the streaming videos by their cell phone and so galore other facilities. |
