LTE Fundamentals - Course Documentation 2010

8/10/2019 LTE Fundamentals - Course Documentation 2010

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5 >4 >8 >12 >16 >18 1

16 QAM 5 4 8 12 16 18 1

16 QAM >5 >4 >8 >12 >16 >18 1

Figure 70 - Reduction of peak power, bandwidth and modulation


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6 Considerations for LTE Radio Spectrum


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6.1 Overview of Radio Spectrum

Spectrum is known as a portion of the electromagnetic spectrum occupied by radiowaves, in other words, used mainly for telecommunications. Spectrum is a valuableresource and time limited, it is necessary to make a rational and efficient use of it.

At present there is a growing demand for spectrum for new wireless servicesconsolidation, as evidenced by, among others, mobile communications systems,networks of terrestrial digital TV broadcasting or the various systems of wirelessbroadband access.

This growing demand is necessary to add that not all parts of it with the samecharacteristics, resulting in different coverage capabilities or different properties fromnoise and interference, love of technology or cost implications. Also different types ofinformation (voice, audio, data and video) require margins of spectrum (frequencybands) specific. All these features lead to so far have been found in some specificareas of the spectrum are particularly suited to provide some specific services,including, at times, inevitable conflicts between different services competing for thesame frequency band.


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6.2 Actors involved in spectrum management

Considering the trend of offering broadband services using wireless systems, and itstime considering that end-users, in their role as purchasers of services and recipientsof public telecommunications services, they need among other things, to havesufficient spectrum to enjoy new applications and services that require thisbroadband, competition is predicted by the acquisition of spectrum by differentstakeholders. These actors include:

Equipment manufacturers and telecommunications Emperor: The operatorsoffer services based on a technology and using standard equipment features.This is how the radio equipment are negotiated between manufacturers ofsuch equipment and operators of telecommunications services. Because ofthis telecom operators must comply with the frequency recommended by theoperators who are in the vanguard, who ultimately encourage the frequenciesat which it must operate a given technology, taking into consideration thecharacteristics and availability of spectrum they possess. Failure to do so,each operator would have to manufacture equipment (eg mobile devices) on asmall scale, making the unit cost will be higher.

Regulators: The radio spectrum is a public good. In each country there is acontroller that manages the use of frequency bands in it. The regulatory bodyacting under its "National Plan of Frequency Allocations" and the rules andrecommendations, international, has the power of management, administrationand control of radio spectrum, including the powers attributed to certain uses,specific bands assign frequencies to specific users and monitor their correctuse.


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6.3 LTE spectral efficiency

In telecommunications, the spectral efficiency is a measure to know how well used isa particular frequency band when transmitting data ( bits ).The higher the value,better exploited is that bandwidths mathematical definition is defined by the followingformula:

Where E is the spectral efficiency, R the transmission rate in bps ( bits / s ) and B thebandwidth of the channel in Hz, therefore, the spectral efficiency is measured in bps /Hz (bits / second / Hertz).

One of the priorities that are looking to LTE, is to improve spectral efficiency. Below isa comparison between the LTE and other technologies.

Spectral efficiency of mobile technology

Technology Spectral Efficiency (bps / Hz)

GPRS 0,07

W-CDMA 0,4

HSDPA 2,8

HSPA + 2x2 8,4

LTE 5

LTE 2x2 8,6

LTE 4x4 16,3

Figure 71 - Comparative spectral efficiency

Visible as the incursion of new technologies much more efficient, as is the case ofLTE, will allow better use of the spectrum.


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6.4 Spectrum bands allocated for LTE

The international body 3GPP has identified some of the bands identified for UMTSLTE, also support FDD (Frequency Division Duplex) and TDD (Time DivisionDuplex).The Agency has identified 15 bands for FDD mode operation and 8 bandsfor LTE TDD operation, which gives operators the flexibility to adjust their networks,spectrum and existing business objectives for mobile broadband services.

The figure 50 above indicated the current distributions of these frequencies. As notedin the table, the ranges defined for LTE frequency range from 700 MHz to 2.6 GHzbands also mentioned, there are others that are in the process of study such as thedigital dividend (790 - 862 MHz), 3.5 GHz in the band from 3400 to 3600 and in 3.7GHz band of 3600 to 3800.

6.4.1 Frequency bands currently used for LTE

Today, some telecom operators are investing in order to acquire sufficient spectrumto enable them to deploy LTE. Of the available bands for LTE, which are being mostdesirable for the implementation of this technology are: The 700 MHz band, the bandof 1.7 and 2.1 GHz and 2.6-GHz band.

Three operators are betting on LTE in these bands are listed below:

NTT DoCoMo (Japan) in the 2.1GHz band. Verizon Wireless (USA) in the 700MHz band. TeliaSonera (Sweden and Norway) in the 2.6GHz band.


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6.4.2 Aspects to consider when choosing thefrequency of implementation

Moreover, when comparing two of the bands for LTE world (the 700 MHz comparedto 2.6 GHz), in terms of coverage of 700 MHz provides better coverage and requiresusing fewer base stations as shown in the following figures:

Figure 72 - Frequency bands and radio coverage ranges required bases


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For example, if we compare the use of 700 MHz compared to other higherfrequencies, the network infrastructure, network costs (CAPEX) are approximately4.5 times less than if we use the 2.5 GHz band and about 1, 3 times if you used the850 MHz band.

CAPEX relative percentage required for

investment in network infrastructure

Figure 74 - Comparative CAPEX investment by the spectral band used

That is, the option of deploying LTE in the frequency band of 700 MHz, turns out tobe the optimal choice if you are looking for great coverage with little infrastructure,contributing to reducing the digital dividend. Furthermore, as noted above, for theoperator this will represent a reduction of costs associated with the implementation ofthe network.


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Today the 700MHz band is currently used for UHF television services, as happenstoday in most European Countries. Regarding this aspect, with the conversion ofanalog to digital television (DVBT, which will free up a significant portion of radiospectrum in the 700MHz band, called digital dividend. The following figure providesthe portion of spectrum allocated for digital dividend, with the range of 698-806 MHzthat is allocated for this purpose.

Figure 75 - Spectrum plan mobile and digital TV

6.4.3 The choice of refarming as an alternativeimplementation

Today, some telecom operators are considering future reuse of existing GSM andUMTS bands for LTE deployment. This process of reusing or rearranging of the radiospectrum when deploying a new radio technology is known as "Spectrum refarming."

This is because the cost to the operator to make purchases of new spectrum.Therefore most of the operators should consider the possibility of reorganization ofthe spectrum so that it is reused for LTE. However, the operator considers thispossibility should have sufficient amount of spectrum to efficiently support LTEtechnology, while using the remaining spectrum to support the traffic of other legacytechnologies. This requires cooperation and coordination not only between theparties concerned, but also with the relevant regulator.


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6.5 Amount of spectrum required for LTE deployment

An important consideration is to know the amount of spectrum needed to provide theservice capacity offered by LTE.

LTE current specifications suggest that rates could provide more than 300 Mbit / sper cell. However, this applies and requires the optimal configuration of the antennasand radio ideal conditions, any of which can be assumed at this stage of study. Morerealistically, the configurable maximum bandwidth of 20 MHz, the estimatedmaximum data rate (peak) of 100 Mbit / s is estimated that for this bandwidth, anaverage of 40 to 50 Mbit / s may be achievable. These figures are further reduced ifthe available bandwidth is reduced, as shown bellow.

Attainable speeds with LTE

Speeds

Bandwidth (MHz)

1.4. 3 5 10 15 20

Pico (Mbps) 4.5. 9 20 40 60 100

Average (Mbps) 2.2.5. 4.5. 10 -12 20 -25 35 -40 40-50

Peak with 2x2 MIMO (Mbps) 12,04 25,8 43 86 129 172

Peak with 4x4 MIMO (Mbps) 22,82 48,9 81,5 163 244,5 326

Figure 76 - Attainable speeds with LTE

Based on the above, an operator with spectrum in FDD mode shall be at least 2x20

is 40 MHz to deploy LTE in its maximum capacity.


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7 Other considerations on a migration to LTE


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The evolution of LTE could be said to be implemented (the first stages with theanalog FDMA network and the second digital TDMA).Subsequently gave rise to threeclearly defined stages. The first of these steps was the implementation of a GSM /GPRS, the second was the implementation of a UMTS / HSPA, as a third stage aimsto deploy an LTE network in all terms of access and core packages.

The goal of migration is to implement a converged mobile network capable ofsupporting GSM, 3G/HSPA + & LTE. That is, taking into account the design anddevelopment of the LTE, the emphasis is to ensure future interoperability withexisting 3GPP technologies, 3G/HSPA + and GSM. This will ensure that HSPA + andLTE to coexist, and being LTE technology that complements HSPA +, providingincreased capacity in areas of high demand. Initial implementations of LTE will bemost appropriate in specific urban areas of high demand, while that HSPA + will

cover the vast existing HSPA coverage.The figure bellow shows the migration to LTE which international markets have bet,as it is considered that LTE is the technology that will prevail in the medium and longterm.

Figure 77 - Migration Trends in mobile technology LTE

How you can see, it is estimated that 88% of the markets tend to use the evolutionarypath marked with number 1, namely GSM - UMTS - LTE.


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There are several factors that a Telecom operator should take into account whenmoving towards LTE. Among others, we can identify three main parts, which canimpact heavily on the successful development of this technology in the coming years:

Economic aspect: It is imperative that the operator takes into account theinvestments to be made for the deployment of network and parallel to themarket environment, will allow future will recover investments made in theimplementation of this technology.

Regulatory environment: Indicates the legal framework under which governthe networks and services. In this regard, an operator must have sufficientspectrum for the deployment of this technology.

Technological requirements: A telecommunications operator shall evaluate the

existing offerings in terms of terminals and network equipment so that you canimplement this technology. At the same time must take into account thetechnical requirements for the implementation of an LTE network, assessingthe possibility and need for new applications and services can coexist in aconverged environment, allowing the interconnection of these networks withexisting 2G namely, 3G and Wimax.

To summarize, the figure bellow indicates these and other aspects to be consideredfor migration to LTE.

Figure 78 - Planning stages for LTE cell


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7.1 Special considerations must take into account anoperator

In addition to the above considerations, bellow it will be listed a series of morespecific issues, recommended for the evolution to LTE.

7.1.1 Considerations for network planning

Planning involves three stages, which are depicted bellow:

Figure 79 - Planning stages

They correspond to the initial planning stage (Initial Planning), detailed planning(Detailed Planning) and finally the stage of optimization (Optimization Planning).


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7.1.2 Initiation stage

This first stage is to gather information about the networking features to bedeveloped, such as aspects of coverage desired capacity, quality of service to beallocated (QoS), and the portfolio of services to be provided. It also includes theamount of expenditures to be allocated to cover their CAPEX and OPEX. In turn, thesystem must meet the necessary regulatory requirements, among other things.

7.1.3 Stage details

This step involves sizing issues such as estimating traffic by user, location of existingbase stations sites, coverage predictions and estimated capacity, which are requiredfor detailed planning of the network. This stage can be divided into the followingprocesses:

Site Selection: In cellular systems, site selection is an important aspect toconsider. Also includes the number of sites required, key performanceindicators (KPIs, Key Performance Indicator) with respect to coverage andcapacity.

Coverage and capacity planning: For LTE, the planning capacity andcoverage is interrelated. The main objective in the planning of networkcapacity that supports LTE is the requirements of user traffic. For its part, themain target for coverage planning is to ensure network availability and theirservices in designated service areas.

Configuration Planning: The objective of this process is complete the setupof equipment needed for the access and transport networks can provideapplications and services that supports LTE and allow interoperability with

legacy networks, namely 2G 3G and WiMAX.

7.1.4 Optimization stage

The optimization is probably the most important step when planning the deploymentof an LTE network. Typically it can be separated into pre-launch optimization andpost-launch optimization. There are a number of areas that can be optimized, amongwhich include required capacity, coverage requirements, configuration and reuse ofequipment, among others.


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7.1.5 Deploying services over LTE

When deploying services over LTE networks, a telecommunications operator wouldhave the following choices:

1. LTE network dedicate solely to provide data services.

2. Dedicate LTE network to offer data services and offering voice service on 2Gand 3G networks.

3. Using the LTE network to provide voice and data services.

This shows that an operator could start using its LTE network to deliver and support itand data services continue to offer voice service from their 2G and 3G networks. At alater stage could offer this new network voice over LTE. Another option is that theoperator choose the first instance to provide both services on their networks LTE, iewithout going through steps 1 and 2 above.

The following sections explains in more detail these three strategies.

7.1.5.1 LTE data services

The advantage of offering these services exclusively, is that the operator will deploy amore agile LTE access network independent, so do not require complexmodifications and adjustments to its core network to provide voice service. Theabove can be seen on the next figure.


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Initially, the deployment of LTE technology, could be done in areas of high traffic(known as Hot-Zones) established by the operator or operators interested indeploying the technology. The above is shown on the next figure.

Figure 81 - Areas LTE

For his part, although users could not achieve the same speed of access outside thenetwork coverage LTE, a future operator would deliver multiple access devices(compatible with LTE, GPRS and UMTS) to enable them to parity and transparencyof services used by the user and also allows the user to stay connected.


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Incorporation of MME

23,401 TS specification defines the method Release 8 for interworking accesstechnologies (I-RAT interworking) requires SGSNs in the network are alsoupgraded or replaced. The main premise of this method indicates that theMME is incorporated into 2G-3G legacy networks as another SGSN and the P-GW acts as a GGSN.

The multi-mode terminal that also supports or has the ability to LTE will becoupled to the network using the P-GW/GGSN, macro anchor point formobility, as shown in the figure below:

Figure 83 - P-GW/GGSN macro anchor for mobility


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IDLE mode signaling

Assuming LTE access antennas are installed on the same radio base whichholds 2G and 3G, when a user equipment (UE) performs the handover from2G-3G to LTE, has to perform a procedure called TAU, which if successful, de-register the user to the 2G-3G network and recorded in the HSS to use LTE.

For his part, when you handover from an LTE network coverage to a networkof 2G-3G coverage, it will perform a procedure called RAU and will bederegistered LTE network. This procedure results in a kind of effects such as"ping-pong" with common procedures RAU / TAUS and records related to themobility of user equipment in idle-mode. This increases the signaling traffic.

The next figure shows the trajectory of a UE entering a region with LTE

coverage area and because it enters TAU procedure followed by theprocedure RAUs when you leave these areas.

Figure 84 - Handover 2G-3G to LTE and vice versa

This effect occurs when there are multi-mode terminals in the network.Importantly, the data card (Data cards) are not expected to generate thiseffect, but have the capacity for multi-mode, do not tend to have the ability tohandover from the point of view of mobility.

3GPP proposes a technique to simultaneously perform the RA and TA. This

technique, known as the Idle-Mode Signaling Reduction or ISR, proposed notto increase the signal when the EU is going through a border to change radio


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technology coverage. EU User Team ISR mode will be simultaneouslyregistered in both technologies and re-selected cells in both technologies.RAU recording is activated or TAU only if there is a change in the EU has

mobilized off the lists TA or RA.The benefit of ISR leads to increased paging due to EU should be paged inboth technologies. Due to the need for simultaneous paging, the ISRarchitecture that supports must be compatible with a user plane commonanchor for the two radio technologies.

The 3GPP Release 8, the common anchor point is located in the S-GW.Therefore, when a packet arrives at the S-GW and sent to a UE in idle modebenchmarks S4 and S11 can be used to make the paging request to initiatethe MME and SGSN. It is important to note that the method of I-RAT

interworking cannot be used to support ISR, since in this case the commonanchor point is the P-GW and the page cannot be initialized from it. ISR isbased on the network is capable of supporting I-RAT according to thespecification TS 23.401 of Release 8 so that the S-GW becomes the anchorpoint for the 3GPP technologies. As a minimum, the legacy SGSN they shoulddo the upgrade to support the S3 and S4 interfaces and a new interface S6dat HSS.

Therefore, the method Release 8 has the advantage of eliminating Idle modesignaling through dual RAT records, but this requires updating the existingSGSNs pass S3/S4 interfaces. The method described in the specification ismore practical 23.401 TS cannot require them to SGSNs upgrade.

7.1.6 Voice over LTE

While LTE has the advantage of being a fully network packet switching, has thedisadvantage that services like voice calls and SMS messaging, today's majorrevenue generators for mobile operators, no preliminary be available from an LTEaccess network, since they are based on circuit switching. To counter this problem,3GPP has made several solutions to counter this problem, it will be described below.

7.1.7 Circuit switch fallback (CS fallback)

CS-Fallback solution (specified in 3GPP TS 23.272), is based on 2G-3G networks to

provide voice services over LTE and allows subscribers to LTE terminals transition toa circuit switched network for 2G-3G receiving voice services. Although CS-Fallback


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SMS service for the terminal can remain in the LTE network. To receive a message,the message is forwarded from the MSC to the MME with the interface Gs / SGs andthere with RRC signaling on the LTE radio network to the terminal. The shipment

from an LTE terminal is similar but is not required to return to the legacy networks.No doubt the use of this mechanism for voice and messaging is not as simple as onemight think at first, but it can function as an intermediate solution for voice whileestablishing a concrete mechanism to provide these services over IMS.

7.1.8 Solution VoLGA

As explained above, LTE is a wireless technology based data access in an all-IP.Given that an organization called Volga Forum has proposed a solution known asVoice over LTE through Generic Access (Voice Over Generic Access via LTE orVolga) which aims to provide mobile operators the ability to provide voice andmessaging services through LTE access networks based on 3GPP standard calledGeneric Access Network (GAN).Using this standard GSM, UMTS and LTE, VoLGAhas the ability to provide mobile subscribers voice services, SMS and other servicesbased on circuit switching, when they make the transition years between the 3GPPaccess technologies, leveraging existing 2G-3G network.

Figure 86 - Volga solution for supporting voice services in LTE


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VOLGA solution requires a driver access network (Vance, VoLGA Access NetworkController), which must be added to the core of the current GSM / UMTS. This driverwill support the creation of IP tunnels in order to provide messaging services andVoice over LTE.

From the point of view of the LTE network, the VANC connects to the P-GW overIMS interface. For the other teams behave more like an IP node.

Now from the point of view of the circuit switched network VANC connects to GSMand UMTS MSC as the first VANC sees as a BSC while the latter sees it as a RNC.In addition to support voice and SMS is not necessary to amend the various nodesconnected to Vance.

When a terminal is initialized and detects the LTE network, the first thing to do is

register with the MME. The MME retrieves subscriber information from HLR / HSS.After that proceed to establish the connection to the VANC, which requires an IPaddress which can be stocked earlier in the terminal or obtained via a DHCP server.Since the IP terminal establishes an IPSec tunnel toward the VANC and then registerwith the MSC using the protocol DTAP (Direct Transfer Application Part).


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For the process of handover from a GSM network or UMTS to LTE, the process is asfollows:

When the eNodeB detects that the terminal can be served better by cells of aGSM / UMTS, instructs the device to make measurements of signal strengthfor these cells. Based on this information the eNodeB tells MME is required toperform the handover

The MME informs the VANC that the handover will be performed by amessage indicating the identification of the target cell and the subscriberidentification

The Vance uses this information to create a message of handover that isstandardized. If the destination cell is attached to the same MSC that VANC,then the process is prepared locally and the handover takes place once thecell is ready. If you are connected to another MSC initiates a standardprocedure for inter MSC handover.

Figure 87 - Volga process for handover between 3GPP networks


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7.2 Offer LTE-capable terminals to allow for QoE

Operators looking to deploy LTE will need to offer terminals that support multipleaccess technologies with networks that enable mobility and service continuitybetween GSM, GPRS, UMTS and LTE. Parallel to this, subscribers to LTE expect abetter service, which includes improved speed and applications over 3G.

Moreover, a comprehensive coverage including 2G-3G interoperability is essential,hence the need to offer terminals to obtain better performance with respect to whatoffer 2G-3G terminals today, for voice services and new multimedia applications.

Linked to this, the user is looking to have quality of experience (QoE, Quality ofExperience).QoE takes into account any factor that contributes to the perception ofservice by the user and this includes factors such as speed, bandwidth, coveragearea, mobility, cost, customization, etc.

To provide QoE, according to user expectations, then discusses two critical factors toconsider in the implementation of LTE systems:

LTE terminal must be capable of processing high data rates with low latency. The LTE system will provide transparency and parity of services to the mobile

terminal. This means that the terminal must allow access technology agnostic,allowing users to stay connected (always on).

In general, today's 3G networks do not offer to subscribers in the service quality data.Instead, today's users are subject to the best effort when access to data services.

7.2.1 Election of the terminal (UE)

When choosing the terminals should be taken into account the preferences that theuser has. Other critical factors include multimode terminals, multi-band terminals,capable IPv4/IPv6 and skills as SRVCC or CS-Fallback. These considerations areextended as follows:


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7.2.2 Multimode terminals

In order to provide the user with a wider coverage, not only needs to build anarchitecture that allows the coexistence of 2G, 3G and LTE. Also need to provide thiscapability multimode terminals. This will allow the user access to services, regardlessof the technology used.

7.2.3 Multiband terminals

To complement the feature of multimode, several radio frequency bands for LTEenabled. For this reason, the operator must ensure that the user has access to multi-band devices with this capability that allows users to enjoy mobility, equality andtransparency of service.

For example, mobile operators in Europe and Asia use different frequency bands thatare also used in North America.

Depending on the operator and the country, European and Asian operators using thefrequency bands of 900 MHz (GSM) 1800 MHz band (DCS) and 2100 MHz band (W-CDMA). In North America, you use the 700 MHz band, 800 MHz (mobile), 1700/2100MHz (AWS), and 1900 MHz (PCS).

Some other important features that the user equipment must support are:

Handover for voice between LTE and 3G networks, the terminal requiresSRVCC support capacities.

Turn requires support CS-Fallback capabilities. A terminal that supports VoLGA defines its capacity for voice services, it also

requires a set of requirements for interacting with the IMS platform. The voice terminals operating in LTE required to have location capabilities.

One of this method is the Assisted Global Positioning System (AGPS). LTE terminals must also support services such as SMS.


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7.3.2 EPS Carrier

Considering the qualities of an "All IP" and the nature of bursts in data services, from3GPP Release 8 introduces the concept of EPS carrier, called from now on as"carrier" for simplicity.

The carrier is a concept from which identifies packet flows receive the sametreatment in terms of quality of service between the terminal equipment (UE) and thegateway PDN-GW. PDP context is equivalent to the standards used in 2G/GPRS and3G/UMTS. The carrier is composed of three elements, namely:

S5 Carrier: implemented through a tunnel that transports packets between theS-GW and the PDN-GW

S1 Carrier: implemented through a tunnel that transports packets between theS-GW and eNodeB

Radio carrier, implemented by a protocol connection with RLC (Radio LinkControl) between eNodeB and the EU.

Figure 89 - EPS carrier elements and their location in the network


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Resource type: determines whether the carrier is GBR or not RBM. Priority: is used to differentiate the connections SDF. Each QCI is associated

with a priority, with 1 being the highest priority. Packet delay budget (PDB, Packet Delay Budget): refers to the possible

latency of data packets transported between the terminal and the PDN-GW.This is the same for the downlink and up to one QCI.

Packet loss rate (PLR Packet Loss Ratio): describes the maximum rate ofpackets transmitted to the upper layer of all packets processed by the linklayer. Like the PDB is the same for the uplink and downlink for the same QCI.

In addition to the carrier level parameters, there is a parameter of quality ofservice associated with the terminal called maximum aggregate bit rate(AMBR, Aggregate Maximum Bit Rate) which applies only to non-GBRbearers. Serves to limit the bit rate of subscribers differently, it is also definedbut not for a carrier to a carrier group of a subscriber


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7.3.4 Packet Filters

A packet filter has to be created in the PDN-GW (and signaled the EU) of each SDFin order to allow proper allocation of the data in the EPS bearer channel and correctrouting. The EPS bearer channel is associated with a TFT (one on one in the UL andDL) and therefore an EPS bearer channel can carry only one SDF, while all data fromthe same EPS bearer experience the same QoS. The SDF can be assigned a samecarrier EPS only if they have the same QCI and ARP.

The packet filters are sequentially applied to the input data (in the EU in UL and DL inthe PDN GW) according to values of packet filters in the Index-Evaluation-Priority. Ifthe data do not match should be sent to the carrier that has no associated packetfilters. If no such carrier data must be returned.

The packet filter package has a unique identifier (1-8) in the TFT and consists of oneor more of the following attributes in terms of its configuration with respect to theapplication that entail:

Source / Destination IP address subnet mask Number of protocol overhead (eg, TCP / UDP)

Destination port range. Source port range. Index IPSec security parameter. Service type, identifies the quality of service Flow level, only used for IPv6

7.3.5 Mapping the QoS parameters for UMTS andEPS

Since its beginning in LTE / SAE will have to live with 2G/GPRS and 3G/UMTSnetworks, it is necessary to map the parameters between networks as they aredistinct together. The following figure summarizes the mapping between parameters.


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PDP R97/98 PDP R99 EPS R8

Delay Traffic Class Carrier Type

Priority traffic management

Reliability SDU Error Rate PLR

Bit error rate residual

Delivery of erroneous SDU

Peak transfer rate Maximum bit rate for uplink MBR

Maximum bit rate for downlink

Precedence ARP ARP

Average transfer rate N/A N/AN/A Maximum SDU size N/A

N/A Transfer delay PDB

N/A GBR GBR

N/A N/A AMBR

Figure 91 - Mapping of QoS parameters for UMTS and EPS


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7.4 Implementing a solution SON (Self OptimizingNetwork) to support efficiency

This section identifies two important measures that the telecommunications operatorshould take into account when deciding to migrate from one network GSM-UMTS toLTE. The first one is to increase automation in the management of radio accessnetwork and the second concerns as to efficiently activate new subscribers.

The mobile telecommunications industry is developing LTE to support a wide varietyof applications requiring high data rates and signaling requirements resulting in

robust quality of service (QoS).The implementation of a large number of base stations (eNBs) Femtocells known asHome-eNBs is within a highly complex since it combines a number of parametersthat must be put in place and to ensure interoperability.

One of the main specifications created by the International TR36.902 3GPP isindicated regarding the Self-Optimizing Networks (SONs).

The Sons automatically configure and optimize networks in order to minimizeoperating costs. SONs displays the interaction between base stations and connectingthem with the Core Network, with the aim of improving the functions of embeddedoptimization. The three main features of SON are: self-configuration, self optimizationand self-healing.

7.5 Reuse of access equipment

It is always advisable to install antennas and feeders separately when installing newtechnologies. This recommendation maximizes system performance, minimizing theimpact on existing systems, eliminating the interaction during the optimization of thenetwork, minimizing interference and simplifies the tasks of Operation, Administrationand Maintenance (OA&M).

However, mobile operators 2G and 3G are looking to install multiple antennas ateach base station, because the sites where these antennas are usually installedrentals and permit application required for the installation of the same and this meanshigh costs. Therefore, making sharing of antennas located at a base station BTS cansave time and money.

This technique can be divided into two main categories: Multi-Band and Co-Band.Mobile phone operators 2G-3G most likely be using both techniques to combine


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GSM and UMTS. This could complicate the purposes of implementing the same siteantennas for the new LTE technology.

Multi-band technique: Techniques for Multi-Band combines the signalsreceived and transmitted from different base stations operating in differentfrequency bands.

Technical Co-band: The Co-Band techniques combines the signals receivedand transmitted from different base stations operating in the same frequencybands.

For its part, must take into account the shared antenna systems, share patterns andcoverage antennas, this means that an adjustment in these antennas to optimize thesystem could affect the operation of the entire system of sharing the antennas.


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7.6 Reuse and improvement of network backboneand backhaul transport

Here arises an important question, Are you ready to decant cellular operators in theirnetworks exponential growth in data traffic? The answer is no, because in generaltheir transport networks (backhaul) are based on technologies and protocols thatwere designed for voice traffic. Importantly, the backhaul network is connectingaccess nodes to the backbone IP network.

Figure 92 - Backhaul Backbone and IP

The data transmission networks of the operators will have to reach eventually migrateto new technologies, which allow the growth of data traffic while maintaining theprofitability of operators. This challenge can only be achieved with a transportarchitecture that is efficient in data traffic, and that has a wide possibility of scalability.


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Do not forget also that the demand for voice services continues to grow, and networktraffic increases not only the data but in the traditional services. Thus, it imposes agreater need to free up capacity on legacy networks, and to accommodate data trafficin the infrastructure of next generation based on IP / Ethernet that allows for growthby increasing costs marginally, to introduce technologies such as HSPA+ and LTE.

Among the major requirements to be met by a backhaul network to support LTE are:

Increased capacity: 100 Mbps exceed its deployment Low Latency: must meet requirements of 10 ms for point to point Improved services: should point to point interface (S1) and multipoint interface

(X2) efficiently Support services and legacy equipment

Moreover in the industry are shuffled some figures regarding the ability of eachtechnology required for transport:

HSPA supports 50 Mbps per sector HSPA+ up to 100 Mbps per sector LTE will support up to 170 Mbps per sector

More details of the Japanese manufacturer Fujitsu suggests that the capacityrequired per site is only the spectrum (channel size) available by the operatormultiplied by the spectral efficiency of the air interface. The following figuresummarizes these requirements for various wireless access technologies.


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TechnologyVocal

Spectrum(MHz)

Spectrumdata (MHz)

VoiceSpectral

Efficiency (bit/ Hz)

Data SpectralEfficiency (bit

/ Hz)Sectors % Utilization

Requiredcapacity(Mbps)

Number ofE1s

2G GSM 1.2 - 0.52 - 3 70% 1.3 1

GSM / EDGE 2.75G 1.2 2 - 3 0.52 1 3 70% 6.1 4

3G HSDPA - 5 - 2 3 70% 21.0 14

LTE - 5 - 3.8 3 70% 39.9 N/A

LTE - 10 - 3.8 3 70% 79.8 N/A

Figure 93 - Requirements for mobile network capacity

As shown, for a site with 3 sectors and a 5 MHz channel capacity will require about40 Mbps, while for a 10 MHz channel will be 80 Mbps and thus the requirement willincrease to reach 20 MHz channel that supports LTE.

7.6.1 Evolution LTE backhaul

Today the vast majority of operators have to transport TDM voice and data backhaul.The option to keep adding E1 to provide more capacity becomes immediatelyfeasible, since it would require a disproportionate amount of them to support trafficgrowth is anticipated in the future. Fortunately, industry and operators have identifiedthe technologies to start migrating their transport networks in order to accommodatethe growing traffic.

The future of transport networks of cellular operators offer goes through the Ethernet-based services and transport networks based on IP / MPLS and Carrier Ethernet,which lived for several years with the networks eventually replaced, as TDM, ATM,SDH / SONET and Frame Relay, which have been used to carry voice traffic anddata over E1 connections, mainly.

In fact, the convergence of transportation costs needed to manage these services donot increase proportionally to use, has caused the Broadband Forum, which tookover the IP / MPLS Forum-unite with the Metro Ethernet Forum ( MEF) for IP / MPLS


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to offer Carrier Ethernet services. It seems that in future transport networksaccounting is themselves with a portion in the core IP / MPLS and other nearby basestations, based on Carrier Class Ethernet, which has attributes conducive to cellular

backhaul, as for example:

Standardized services Scalability Quality of service Reliability Service Management

The dilemma of the operators is, therefore, how to perform this migration whilerespecting the existing services that now account for most of the income, whilepreparing its transport network to evolve its offering of data according to the expectedgrowth is projected for the next three to four years.

For operators with large investments in TDM migration route is more feasiblecoexistence, at least initially, TDM to Ethernet networks, where networks wouldhandle all existing TDM voice traffic while the data stream is transported overEthernet . And is that even though it might seem that managing two networkssimultaneously affects a high OPEX for the operators, the costs would becomparatively lower than more input E1 lines for greater data capacity.

And in the future transport networks will necessarily migrate to data transmissionnetworks where Carrier Ethernet and IP / MPLS current bets seem to offer Ethernet-based services and emulate those based on legacy technologies. Strategically,cellular backhaul over Ethernet allows not only to offer services HSPA today, butleaves the transportation network ready for launch of HSPA+ and, above all, LTEwhich is an IP network from end to end and whose base stations have only Ethernetinterfaces for transport tasks from the base station to the core of the operator'snetwork.


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7.6.2 Transport backhaul technologies LTE

To meet the transport capacity growing demand, the following technologies areevaluated, backhaul fiber and microwave backhaul ranges 6-38GHz and 60-80 GHz.

7.6.2.1 Optical fiber

Fiber is technically very good complement to the backhaul. With systems that caneasily scale it beyond 10 Gbps, the fiber will solve any problem that may haveoperators in terms of capacity requirements. The fiber can be deployed in redundantring topologies, high-capacity but the infrastructure to do so can significantly increasecosts. Finally, the fiber is capable of Synchronous Ethernet allowing the managementof multiple service levels and providing synchronization LTE. Given thesecapabilities, if the fiber has already been deployed and is available, is the perfectoption for LTE backhaul.

7.6.2.2 Microwave

Traditionally, microwave (range 6-38GHz) have capacity constraints in a rangebetween 150 and 300 Mbps, however, with new technological advances in themicrowave field may give more than 1 Gbps and some systems up to 4 Gbps. Thereare still many versions of microwave systems available, with packages based onmicrowave technology commonly used for backhaul. For its part emerging microwaveproducts are offered to distribute synchronization capabilities for LTE base stations.

Also, some of them are equipped with ring exchange capacity, ie allowing to setdifferent ring architectures dynamically, with service capabilities high endperformance.


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7.6.2.3 Millimeter Wave Technology

Recently, some operators have begun to evaluate millimeter wave technologies for4G backhaul. These products can generally meet the requirements of 4G capacitywhen most systems reach only 1 Gbps capacity. Many of these systems prioritizationso that they can be multiple levels of service. 60-80 GHz systems do not currentlyprovide Synchronous Ethernet capabilities but it is assumed that they probably willbecause the LTE deployments require. In economic terms, the costs of 60-80 GHzare quite similar to those of 6-38 GHz microwave

On the other hand, the greatest challenge millimeter wave systems is its availabilityand the resulting range of capabilities due to rain fade. Because these litters are atmillimeter wave frequencies as high, are very susceptible to rain, resulting in limitedsections of link in order to achieve reasonable capacity. It is also limited to less thantwo miles stretches.

Then noticed that there are several viable options to meet the requirements ofbackhaul and access networks is predicted, LTE network will use any onetechnology. Certainly there will be a mixture of two or more optimal networktechnologies driven by the location of the site and distribution sites. For newconstruction sites that require miles of range, shows a typical preference formicrowave technology from the perspective of cost and accessibility. However, in alarge network find fiber in the central area where very high capacities are requiredand may be some millimeter wave technology in sectors where the scope permits.


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7.7 Summary of proposed technical requirements fordeploying LTE

In general we could say that if an operator want to evolve their existing networks toLTE, changes in these networks consider switching at the hardware level (additionsand / or upgrades), software (upgrade or update), or hardware and software at atime. This can occur in both radio access network as the core of the network.

3G/LTE Network basically consist of:

Radio Access Network 3G/LTE - RAN (Radio Access Network) Packet Switched Network - CNPS (Core Network Packet Switching). IP Transmission System for Fiber Optics Support System O&M for each of the three previous items

7.7.1 Frequency bands for equipment

The operator is responsible for the suitability of spectrum for operation of GSM,UMTS, HSPA+ and LTE. For example, the working frequency of the equipment forLTE (FDD and TDD) may be any of the following frequency bands:

2100 MHz (1920-1980/2110-2170) 1800 MHz (1710-1785 / 1805-1880 MHz) 850 MHz (824-849/869-894) 700 MHz in the case of release of the Analog TV spectrum in this band.


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7.7.2 Modifications to the data network

The system should include all elements of hardware and software for theoperation of the data, with the latest revision of UMTS/HSPA+ & LTE, bothCNPS data backbone (Core Packet Switching Network,), as in the basestations ( Node B) and the RNC (radio network controllers).It should allow theoperation of this network to UMTS / HSPA / HSPA+ & LTE data mode with thelatest versions of available terminals.

There should be no hardware or software limitations on the nodes of thesystem to prevent the use of all data features adopted by the 3GPP to date inmaking the network implementation. In this sense, should be included everyelement of network-level hardware (HW) and software (SW) considerednecessary for the proper functioning of the system.

Integration should include physical and logical level of all elements of the3G/LTE network with the current GSM network. To this effect should considerall logical interfaces required for such integration, as well as with regard tophysical integration.

The system to be implemented to allow for the coexistence of UMTS, HSPA,HSPA+ and LTE. It is important to mention that the 3G NodeB should havechanges at the HW and SW (upgrade) for it to support LTE and theirrespective protocols.

A Packet Switched Network (CNPS) for UMTS, HSPA+ / LTE 3GPP Release 7and 8, which must comply with the technical specifications, among manyothers at least should include, the following items :

o A Serving GPRS Support Node (SGSN) R 7 and 8.o A Gateway GPRS Support Node (GGSN) R 7 and 8.o SAE Gateway architecture (SAE / LTE).o MME architecture (SAE / LTE).o HSS.


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7.7.3 Technical Requirements multistandard basestations (UMTS/ HSPA +/ LTE)

It should be noted that the migration of existing UMTS-HSPA towards LTEtechnology, is considering the possibility of reusing existing base stations equippedwith technology SDR (Software Defined Radio).This technology allows the use of acommon hardware platform capable of supporting different radio interfaces (GSM,UMTS and LTE) through a software update.

Both are defined by at least the following requirements:

Type outdoor base stations and also distributed multistandard UMTS / HSPA /LTE.

In each radio base should be able to insert modules UMTS/HSPA+ and LTE inthe same cabin or cabinet. Initially, the base stations will be equipped withUMTS/HSPA+.

The base station should enable the joint operation of UMTS and LTE, with anefficient and optimized transport, synchronization, energy and management.

Nodes B and RRU for UMTS must comply with the recommendations andsubsequent developments Release R7 (R8, etc.).

The RRU eNode B and LTE must comply with the recommendations andsubsequent developments Release R8 (R9, R10, etc.).

Based on the foregoing, the Node B must be enabled to HSPA +functionalities and other features of this Release (eg Iu-PS and Iu-CS over IP).

The base stations must support a minimum of 3 sectors. It is up to each network provider the amount of RRU that will be needed by

industry. LTE should be able to allow for the use of MIMO antennas (2x2 and 4x4) in

both Rx and Tx. The base stations must withstand operation in the bands allocated to LTE. All base stations should have the following characteristics:

o Integration with the system operator "All IP" as well as backhaulinterfaces Fast Ethernet to support UMTS / HSPA / LTE

o Base Stations must be able to logically separate voice and data traffic indifferent VPNs:

a) VPN for voice traffic of UMTS / HSPA + (interface lub-CS).


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b) VPN data traffic for UMTS / HSPA + (Iub interface-PS)

c) VPN traffic from one eNodeB to another eNodeB LTE Interface(X2)

d) VPN traffic to a eNodeB LTE MME interface (S1)

e) VPN traffic from one eNodeB to LTE-SAE GW (S1-U interface)

These VPN must be multiplexed onto the same physical interface, or Fast-Ethernetinterface the minimum amount possible.

The base stations should support the following types of services, details ofwhich shall specify:

o CS Domain Services (voice and data transparent and not transparent to

different rates).o PS Domain Services.o Combined services (voice, data services in the CS domain, domain

data services in PS).o Location Services handovers (Softer, Soft and Hard, including

bidirectional handover 2G-3G and 3G-4G).o Access technology of the E-UTRA (base stations) to LTE will be full

duplex FDD.o LTE should be possible to use flexible bandwidths from 1.25 MHz to 20

MHz.o In the downlink, OFDMA and 64QAM modulation schemes, 16QAM and

QPSK.o In the uplink SC-FDMA and BPSK modulation schemes, QPSK, 8PSK

and 16QAM.


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7.7.4 Technical requirements of the Radio NetworkController (RNC)

The RNC is the component of the UMTS network responsible for controllingthe Node Bs (base stations) via the Iub interface.

The equipment manufacturer should describe the various architectures and E-UTRAN supported by their equipment, but shall at least comply with thereference architecture.

The manufacturer shall provide all the technical facilities of the RAN (RadioAccess Network UMTS, HSPA+ and LTE).Here are some of the mostimportant.

The folling table depicts Facilities RAN techniques.

Facility Description RAN

Assignment dynamics resources

Dynamic resource allocation of hardware andsoftware according to the QoS requested by

the EU and the burden of the variouselements of the system.

UMTS, HSPA+ and LTE

QoS classes The system must support the four serviceclasses defined by 3GPP (conversational,streaming, interactive, background)

UMTS, HSPA+ and LTE

Control overload

Faced with massive access attempt phones,should provide mechanisms to ensure thatthese efforts do not destabilize the operationof the RAN.

UMTS, HSPA+ and LTE

EU Location Shall provide software functionality thatallows the location of DU LBS for UMTSHSPA and LTE similar

UMTS, HSPA+ and LTE

SMS point to point Ability to send from / to a mobilealphanumeric messages

UMTS, HSPA+ and LTE

SMS broadcast Possibility of sending an SMS while allsubscribers registered in a number of sectorsto be defined.

UMTS, HSPA+ and LTE

Point to point Ability to send / receive MMS in EU UMTS, HSPA+ and LTE


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MMS

MMS broadcast Possibility of sending an MMS while all EUregistered in a given set of cells

UMTS, HSPA+ and LTE

Call Emergency

It should be possible to assign higher priorityto emergency calls (to numbers prefixed)compared to the rest of the calls originated.CS applies to Voice and VoIP.

UMTS, HSPA+ and LTE

Reconfiguration Automatic Channels

logical

Automatic reconfiguration of the logicalchannels

UMTS, HSPA+ and LTE

Control power

Initial control and dynamic power transmittedby the Node B and the EU in all its forms, anduplink and downlink.

UMTS, HSPA+ and LTE

Efficient use resources

sectors and / or Node B

Faced with a lack of resources in a sectorand / or Node B (number of codes, power,processing power, transmission, etc.), Thesystem should allow the redirection of calls to

other sectors and / or Node B same ordifferent carrier. This procedure should actwhen attempting to establish the service andduring the course of a communication.

UMTS, HSPA+ and LTE

Handover intra

ENodeB Intra, Inter eNodeB, with differentMME eNodeB Inter, Inter MME eNodeB thesame but different SAE GW, Inter RAT(Radio Access Technology).

LTE

Handover intersystem

It should allow two-way handover betweenUMTS, HSPA+ and LTE UMTS, HSPA+ and LTE

Mechanisms reselection

sectors

By parameterized algorithms would allow theEU camp in areas that at first would not bethe best server (Sector Hierarchy)

UMTS, HSPA+ and LTE

Scheduling Dynamic allocation of EU resources to uplinkand downlink.

UMTS, HSPA+ and LTE

Compression and IP Encryption

IP header compression and encryption ofuser data

UMTS, HSPA+ and LTE


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Physical Access FDD

FDD for paired spectrum. Uplink andDownlink in different frequency

LTE

Physical Access TDD

TDD mode for unpaired spectrum. Uplink andDownlink at the same frequency, whose plotsmet delays of no more than 10ms.

LTE

Physical Access FDD and TDD

FDD and TDD physical access to the samebase.

LTE

Configuration. common

Simultaneous configuration of commonparameters for associated eNodeB

LTE

Modulation LTE

Downlink: OFDMA: 64 QAM, 16QAM andQPSK. Uplink: SC-FDMA 16QAM, 8PSK, QPSK,BPSK

LTE

VoIP Voice over IP protocol with less delay UMTS, HSPA+ and LTE

Handover to WLAN

Relayed directions between Wireless Accessnetworks and non-3GPP 3GPP.

UMTS, HSPA+ and LTE

7.7.5 Technical characteristics of the packet core

For the implementation of a Packet Switched Network (PS-CN, Packet SwitchedCore Network) UMTS-HSPA+ and SAE / LTE recommends:

The system (ie the set of nodes and packet core functionality) should bedesigned such that it can join other Next Generation Networks (NGN),enabling further expansion of its capacity later.

Includes the acquisition of Gateway SAE / LTE, MME and HSS.

As for the reference architecture is depicted below a generic block diagram of thewireless network, which includes the nodes of the architecture and the interfacesinvolved. Each interface must be considered both from the standpoint of physical andlogical. Blocks and interfaces that are illustrated in the following figure, should betaken as reference, where necessary, for submission of the required information.


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Figure 94 - Proposed system architecture for LTE

This system then must support access 3G and LTE. The system offered by eachoperator must ensure the compatibility of its components with the futureimplementation of functionality as the IMS architecture.

7.7.6 Technical characteristics of interfaces

The system must support the following quoted logical interfaces defined by the3GPP standard: Iu, Gr, Gs, Gd, Ge, Gf, Lg, Gc, Gn / Gp, Ga, Gi, interfaces forLTE (S1-MME, S1-U , S3, S4, S5, S6A, S7, S8a, S10, S11, SGI, Rx) andother interfaces required to implement the architecture referred. Physicalinterfaces must be optical, or optical-electrical connections for Fast Ethernetand Giga Ethernet. SS7 signaling is over-IP (SIGTRAN).

All interfaces shall comply with the specifications: TS 29002, TS 29016, TS29.018, TS 29.078, TS 29.060, TS 29.061, TS 32.015, TS 32.215 and allconnected by them.


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7.7.7 Core Specifications SAE / LTE

Support for multiple types of access: LTE, HSPA, HSPA + and non accesstechnologies standardized by the 3GPP.

Must support air interfaces LTE as well as roaming and mobility between LTEand UTRAN / GERAN: S1-MME, S1-U, S3, S4, S5, S6A, S7, S8a, S10, S11,SGI, Rx +, etc.

Must support interfaces and standards for access to technologiesstandardized by the 3GPP, S2a, S2b, S2C, S6C, S6d, S9, SWA, SWD, SWN,

SWX, SWU and STa. Support for Quality of Service (QoS).

7.7.8 MME techniques features

This node control plane, handles the control signaling for mobility between 3GPP

networks and manage identification and security parameters of the EU. The MMEshall perform the following functions:

Selection of Serving Gateway and the PDN Gateway. Selection of MME to MME handovers with others. SGSN selection for handovers to access networks 2G or 3G. Facilitate roaming between access networks.


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7.7.9 Technical specifications of SAE Gateway

The SAE Gateway consists of two logical entities of the user plane the S-GW and thePDN-GW serving as interfaces between Access Network and the various packetnetworks. These logical entities can be implemented as a single element Network.

7.7.9.1 Serving Gateway (S-GW)

Is the node responsible for E-UTRAN termination. Serving GW functionalities are:

Mobility Management handover between eNodeB. Mobility management for handover between 3GPP LTE and other

technologies. Transmission and routing of packets.

7.7.9.2 PDN Gateway

Is the node to be made by the end of the SGI interface to the PDN.

The functionality of the PDN GW should be:

Seamless mobility management and continuity of user sessions when moving

between technologically heterogeneous access networks (aligned and notaligned with the 3GPP). Application of QoS policies. Packet filtering user. Support charging for traffic between PCRF and the PDN-GW. Location UE's IP address.


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7.7.9.3 HSS Home Subscriber Server

The HSS is the database of subscribers converged LTE, which will be recorded andaudited profiles and devices, and will support future network deployments "All IP".Must support open standards allowing full interoperability vulnerability to theelements of multi-vendor network.

The HSS shall administer:

The identities of subscribers and services. Service profiles. Authentication. Authorization. QoS for Long Term Evolution (LTE) and IP Multimedia Subsystem (IMS).

Shall comply fully with the 3GPP Release 8, to environments multi-vendorinteroperability, these should include standardized interfaces LTE: S6A (towards

MME) S6d (towards SGSN), SWx (towards 3GPP AAA), IMS interfaces (Sh, Cx).Other features are:

Support for Locating Subscribers (Dx, Dh, Dw). 3GPP AAA support for interoperation with non-3GPP networks, reliable and

unreliable. Must support seamless mobility features, and portability of services across IP

networks.

Flexibility to support multimedia services. Database Subscriber Profile converged HLR / HSS.


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7.7.10 Technical management of the system

The architecture of SGSN, GGSN, MME, SAE GW, HSS and other items shouldhave the role of OAM (Operation Administration and Maintenance), which will beresponsible for collecting data (alarms, statistics system HW and SW ), managementand user control of the control tasks of HW and SW, etc.


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8 LTE Business Perspectives

The following are important aspects that allow for a comprehensive overview foranyone interested in implementing operator LTE technology. These aspects indicatea growing trend in the consumption data from mobile terminals existing today. Also,are some commercial LTE equipment that already exist in the market with the aim ofwhich is evaluated by the operators that choose to implement this technologyforward. Finally it includes the case of LTE network deployment made by the operatorTeliasonera, with the aim to indicate that the use and marketing of services usingthese networks today is a reality.


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8.1 Global trend in demand for data

The mobile broadband connection is one way that the user can access the Internetwirelessly from anywhere you are. The following figure shows an estimate of thebehavior of global demand in recent years have had the voice and data services, witha decrease in voice service revenues and an increase in revenue due to the demandfor services data.

Figure 95 - ARPU by traffic type, b) Revenue by type of traffic


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The overall market trend has been perceived by operators such as AT & T, Orange,Vodafone, Telefonica, Vivo and Telstra as shown bellow.

Figure 96 - Wireless markets revenues increased tendency


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In relation to the above, some predictions indicate a steady growth of users whomake use of a large number of devices to connect to mobile networks.

Figure 97 - Wideband subscribers to mobile-device type


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In this connection, the user is expected that greater use of adaptive devices topersonal computers (such as data cards) for wireless access to applications and dataservices.

Figure 98 - Traffic subscribers in mobile access networks


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8.2 LTE as a data access solution

It is expected that the introduction of this technology to market operators havebenefits such as reduced costs as CAPEX and OPEX. In turn, because LTE isfocused on facilitating access to new data services and better rates, it is estimatedthat it allows an increase in revenue for the operator.

Figure 99 - Market trends in mobile broadband


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For their part, some other aspirations and needs as displayed with LTE operators arelisted in the following figure.

Aspirations of operators to deploy LTE

Feature Potential Impact Justification

ARPU Services and value-added applications Revenue from new services Proliferation of broadband devices

CCPU

All-IP networks Backhaul Network Virtualization

Migration, multiple networks, OSSS, etc.

Customerretention time

New applications 4G More devices per user New payment without contracts

CPGA Economy of scale Customer acquisition.

Best subsidies.

Subscribers

New applications for new market segments Higher bandwidths, aimed to improve

performance More devices with mobile broadband capability

CAPEX Economy of scale All-IP networks and spectrum efficiency. Network Virtualization

Multiple networks in transition.

Figure 100 - Aspirations market operators including LTE


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8.3 Operators Initiatives

Today we already have confirmed more than 50 operators committed to LTE in thecoming years. The following figure shows an overview of the operators committed tothis initiative.

Figure 101 - Project operators committed to the LTE / EPC


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To complement this, bellow, depicted with red markers are countries where operatorscommitted to deploying LTE in the coming years. For its part, the blue markersrepresent das networks deployed by the operator TeliaSonera in the countries ofSweden and Norway.

Figure 102 - Map of countries with operators committed to deploy LTE networks

With regard to these deployments, one of the great unknowns in relation to LTE isabout why some traders are choosing to invest and deploy LTE immediately, whileothers have adopted more than a stance of "wait and see what happens."

One explanation is that the resources of the spectrum that the operators havedetermined the technology and time of release. In Europe, for example, manyoperators are strongly committed to LTE will have to wait for the spectrum to be

auctioned, especially in the 2.6GHz band. Operators such as Telecom Italia andVodafone UK are laying the groundwork to deploy LTE, but until the spectrum isreleased, it is difficult to anticipate the time of release of LTE. For its part, the keyband in the U.S. for LTE, is 700 MHz, while the 2.1 GHz band will be more frequentin China and Japan.

Another explanation is the difference between CDMA and UMTS. Operators withCDMA networks - technology that has no next evolutionary stage in their 3G platform- are migrating directly to 4G, while operators with UMTS networks have manyphases of development ahead for their HSPA networks. AT&T for example, seems tohave no urgency to deploy LTE, because the operator has been adding thousands ofsites, antennas, towers, backhaul connection, etc., To support high broadbandspeeds offered through its HSPA network. For AT&T, LTE will add more capacity and


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bandwidth to meet the growing demand for data services. However, the operatorplans to continue developing HSPA speeds increase to 14.4Mbps (now offers aspeed of 7.2 Mbps), then migrate to HSPA+ and finally launch an LTE network in

2012.This means that for some operators to migrate to LTE will be simpler than others. Forexample, operators have already launched a 3G network, will require an upgrade ofits network ahead of its evolution.

Moreover, as shown bellow, two of the main reasons why operators are investing intechnology is the need to offer new services to meet user expectations and thepossibility of reusing existing 3G infrastructure.

Figure 103 - Main reasons why operators are investing in LTE

Addition, as mentioned above, the evolution to LTE is attractive to many operators

because it reduces the CAPEX and OPEX compared to legacy technologies such as3G networks. In fact, a report published by the UMTS Forum indicates that the costper megabyte for LTE services will be 83% lower with respect to (W-CDMA) and 66%lower compared to HSDPA.


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8.3.1 Operators in Asia

In Asia, NTT DoCoMo in Japan is an operator that has been very active with respectto LTE, driven by demand for high-speed data services in the country and thecompany's commitment to implement cutting-edge technologies quickly. Thisoperator has tested at speeds of 250 Mbps in the downlink and 50 Mbps uplink using4x4 MIMO technology. These tests were performed at frequencies of 1.7 GHz in abandwidth of 20 MHz, respectively. For these tests are used equipments frommanufacturer Fujitsu.

NTT DoCoMo plans to launch a commercial LTE network in December 2010, and inprinciple, only be accessible via USB modems for personal computers. For the year2011, would begin selling phones to offer dual LTE/3G national coverage that usersacquire, and a quick solution for the supply of voice and SMS services on thesedevices.

China Mobile for its part, has actively participated in LTE trials with vendors. Thecompany has announced for mid-2010 plans to build a commercial pre LTE TDDnetwork in China and continue the testing stages at the end of this year.

8.3.2 Operators in Europe

In Europe, the operator TeliaSonera LTE deployed in Norway and Sweden and thishas had the support of the company Ericsson and Nokia Siemens Networks.

Another operator is Telefnica (Spain), which has tested getting data downloadspeeds in excess of 140 Mbps will soon begin installation of LTE base stations toconduct pilot tests, which the operator expects to reach speeds Download up to 340Mbps pilot project conducted in collaboration with manufacturers such as Alcatel-

Lucent, Ericsson, Huawei, NEC, Nokia Siemens Networks and ZTE.Other European operators like Vodafone have been tested in Europe with technologysupplied by Ericsson, Huawei and Qualcomm Inc., hoping to start selling servicesover LTE networks between 2011 and 2012.


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8.3.3 Operators in Latin America and the UnitedStates

Many operators in the region (Telefnica Chile, Movistar, etc.), use in paralleldifferent technologies such as UMTS with GSM. According to experts who gatheredat the conference LTE Latin America 2010 held in Brazil, LTE cannot be deployed asa traditional network.

In Latin America until recently, the vast majority of operators deployed their 3Gnetworks, as LTE is an issue that is just beginning to arise. Inclusive, some operatorsare evaluating the possibility to migrate first HSPA + and thereby delay thedeployment to LTE. The following figure shows different scenarios that operatorscontinue to migrate to LTE.

Figure 104 - Plans evolutionary operators around the world


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8.4 Initiatives manufacturers

In this section shows some terminals and LTE network equipment already availablein the market.

8.4.1 Network Equipment

Today, several equipment manufacturers and mobile networks are in some networkequipment market for this technology, other manufacturers are still under design andtest stages. Here are some of the major manufacturers and their network equipmentproposed for LTE.

8.4.1.1 Huawei

Huawei is one manufacturer that offers a solution that allows you to deploy an LTEnetwork without the need to have legacy infrastructure to other mobile networks, italso allows migration from networks such as WCDMA. This solution includesterminals, access network, transmission network SAE and unified management of thenetwork.

The solution proposed by this manufacturer and emphasizes the simplicity of thenetwork, since it combines elements such as SGSN, AG, MME in a single nodecalled unified service node. Also joining the GGSN, PDSN, ASN-GW, PDG, S-GWand PDN-GW in a single node called Unified Gateway.

With respect to the nodes B, they are composed of a remote radio unit (RRU,Remote Radio Unit) which is installed near the antenna, and the base band unit(BBU Band Base Units), both teams are interconnected by fiber optic cables.

To migrate from a node B to HSPA+, its necessary to upgrade the software oncomputers RRU and BBU. To migrate an RRU configured to HSPA + to LTE at thesame frequency band, also due to a software upgrade, however if you use a differentfrequency should change the team by adding a new LTE RRU.

In the case of the BBU, to migrate a card adds LTE (LTE Card) to your computer.The migration process is shown in bellow.


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Figure 105 - Migration process from a Node B UMTS Huawei HSDPA to LTE.


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Today, Huawei offers an evolved Node B called NBS, which support multiple radioaccess technologies (GSM, UMTS, CDMA, TD-SCDMA and LTE).This commercialversion is known as DBS3900 and is shown bellow:

Figure 106 - DBS3900 Huawei Base Station.

Each of these nodes consists of an indoor unit RRU and BBU model 3201 model3900. The unit supports up to 3000 users per eNodeB, in the downlink can achieve173Mbps with a 2x2 MIMO configuration, 64 QAM modulation and a bandwidth of 20MHz, while in the uplink can reach 84 Mbps with 1x2 SIMO, 64 QAM at 20 MHz percell.


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8.4.1.2 Motorola

The Motorola solution includes core network equipment (CPE) and access (E-UTRAN). For the access network equipment manufactured WBR series 500 and 700,which are only eNodeB LTE equipment from Motorola. These support FDD and TDDbands 700, 800, 900, 1800, 2100, 2300 and 2600 MHz, and a variety of bandwidthsranging from 1.4 MHz to 20 MHz.

The purpose of this manufacturer for the core network is based on the number ofWBC 700 teams with mobility management entity (MME WBC 700), gateway packetdata (WBG 700 P-GW) and service (WBG 700 S-GW), policies and billing (WBC 700PCRF) and node management (WBM 700 Manager).

The teams previously mentioned are shown bellow.

Equipment Image Description

It also has a hardware acceleration platformdesigned to accelerate packet processingenabling high performance platform.

High Performance Team, which integrates

advanced services IP gateway securityservices such as deep packet inspection(DPI), stateful firewall, load capacity, andrapid mobility that allows mitigation of security.

Is a router based on the integration of IPservices with support for LTE Gatewayfunctions.

Access equipment that uses OFDM and smartantennas. This equipment allows spectrallyefficient, modular design that supports a widevariety of deployment scenarios

Figure 107 - Equipment Motorola LTE


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8.4.1.3 Nokia Siemens Networks

Nokia Siemens Networks has launched Nokia Flexi base stations (Flexi BTS), withthe aim of providing the possibility of advancing technologies to 2G, 3G and LTE.Platform based on the Flexi base station, radio base extends the capabilities of itspredecessor by incorporating GSM / EDGE, WCDMA / HSPA and LTE in a singledevice.

8.4.1.4 Ericsson

Ericsson has a range of equipment to deploy LTE networks, including the RBS 6000series antennas, which are mobile phone masts are characterized by multi-standardand be prepared to cover both GSM / EDGE, and WCDMA / HSPA and LTE, it iscompatible with previous generations of antenna.


The RBS 6000 series features a compactdesign, so it requires only 25 percent of thespace occupied by previous generations ofantennas. Despite its size, the RBS 6000series has doubled its capacity, while reducingconsumption by 20 to 65 percent over previousmodels. [48]

Provides access to 2G/3G/LTE, MME andSGSN QoS, Router etc. functionality.

Figure 108 - Equipment Ericsson LTE (I)


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Gateway GPRS which supports multi2G/3G/LTE access, functionality MPG,throughput greater than 40 Gbps.

Converged Packet Gateway which providesaccess to 2G/3G/LTE, Release 7 and 8,extensive support for VPN, 200-Gbpsthroughput

HSS and SAPC server for centralized controlof the IMS, can evolve in Release 7 to Release 8 supports up to 60 million subscribers pernode.

Figure 109 - Equipment Ericsson LTE (II)


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8.4.1.5 NEC

This manufacturer offers a comprehensive network solution. It consists of an EPCsystem into one that incorporates all the MME, the S-GW and the PDN-GW. TheEPC system is shown bellow.

Figure 110 - CORE compact network (EPC) for LTE

This system supports about 300 000 subscribers and can handle more than 100base stations LTE.

For its part, the solution for access network consists of units of baseband and radiofrequency (BBU and RRU), also proposes the use of Femtocells LTE to offer bettercoverage indoors. NEC also offers the opportunity for a smooth migration from UMTSnetworks primarily by changes in the elements of network access.


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8.4.2 User terminals

The trend indicates that the devices connected to 3G/4G networks will suffer asignificant multiplication process in the coming years, with the proliferation of smartphones (smartphones), netbooks, laptops, smartbooks (hybrid between netbook andSmartphone) and all portable electronics. LTE is planned to start providing datadevices such cards or USB modems.

Bellow there is a summary of the terminals for LTE, which now have been announcedby different manufacturers.

Manufacturer Model Device

E398 LTE / GSM / HSPA2.6 GHz, 900 MHz USB modem

GT-B3710 (2.6 GHz) USB modem

LD100 USB modem

M13 Modem

RD-3 USB modem

N150 LTE chipset withKalmia Netbook

GT-B3710 USB Modem

SCH - R900 Mobile Terminal

ZLR-2070S Router

MDM9200, MSM8960 chipset

FourGee 3100/8200, 6150for TDD chipset

M700, M710 chipset

LU SMARTi LTE/3G/2GMultimode RF Transceiver chipset

Figure 111 - Device Manufacturers and models for LTE

Hereby some terminal characteristics mentioned above.


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For its part the terminal LG M13 is a dual device LTE / CDMA capable of operating in700 MHz band. This terminal supports bandwidths of 5 and 10 MHz and is expectedto have transfer rates of 70 Mbps in downlink and 20 Mbps in the uplink.

Figure 113 - LG modem M13 Terminal


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8.4.2.2 Samsung

For its part, Samsung has introduced a chipset called Kalmia LTE modem, which hasenabled the creation of model Netbook N150 LTE connectivity.

Figure 114 - Netbooks N150 model


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Samsung also unveiled its SCH-R900 mobile terminal which is expected to beavailable in late 2010 and will operate with the operator MetroPCS in the UnitedStates will be able to LTE and CDMA.

Figure 115 - Terminal Samsung SCH - R900 and modem USBGT-B3710

Samsung also put into operation together with Telia Sonera the USB modem GT-B3710 with downlink capacities of 150 Mbps

8.4.2.3 Motorola

The Motorola LTE terminal Tablet was unveiled at the Consumers Electronic Show(CES) in January 2010, running on a test network operator Verizon, who plans todeploy networks using this technology. The device runs on Google's Androidplatform, has a 7 inch touch screen, 32 GB of internal memory, Nvidia video chip andthe Motorola LTE modem. If this device hits the market could do with an initial cost of$ 300


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8.4.2.6 ST-Ericsson

ST-Ericsson showed its M710 chipset which has interoperability between LTE andHSPA networks, with this the company showed download speeds of 100 Mbps and50 Mbps upload. Its main features are provided by the manufacturer:

Multi-mode LTE / HSPA / EDGE Capacity of 100 Mbps in download, 50 Mbps on the rise LTE UE Class 3 Quad band LTE Tri-band WCDMA GPRS / EDGE quad band band Supports bandwidths of 1.4, 3, 5, 10, 15, 20 MHz LTE MIMO High Speed USB 2.0 USB Ethernet for data access


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8.4.3 Expectations and needs of end users

End users can now enjoy the mobile broadband from their laptops and netbooks aswell as from their mobile phones. Therefore, to provide an improved user experienceis essential and which devices can provide intuitive interfaces and unlimited accessto content and applications of particular interest.

For this reason, the introduction of high capacity mobile devices such as iPhone,have boosted mobile broadband, which is increasingly being used as a substitute forfixed broadband. However, the availability of high quality content, including audio andvideo, has led to a significant increase in data traffic. Consistent with this, is expectedto increase six times in the global IP traffic between 2007 and 2012 (mainly driven byvideo services), which will have an impact on mobile networks and fixed networks.This projected growth justifies the view of operators for LTE technology for mobilebroadband.


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8.4.4 New services can be provided with LTE

The primary objective of deploying LTE technology is that by far exceed thecapabilities offered by today's 2G and 3G. Following are a series of new services orimprovements to them that the operator would be able to provide to Technology LTE.

The following table depicts the mobile services that offered by LTE.

Enabled services and improved over LTE Technology Sector LTE Ecosystem

Components / features inthe service applications and devices

Consumer Services

Devices anduser interfacesand service-specificapplications

* Innovation in allcomponents: operatingsystem (OS), protocols,processors, antennas,batteries, multi-touch screens.* Interactive interfaces.

* User-friendly services.* Open platforms which allownew applications,

Documents

LTE Fundamentals - Course Documentation 2010