FDD LTE Indoor Coverage

FDD-LTE Indoor Coverage

ContentsFDD-LTE Indoor Coverage IntroductionFDD-LTE Indoor Coverage SolutionFDD-LTE Indoor Coverage AnalysisFDD-LTE Indoor Antenna Configuration

What does Indoor Coverage Cover ? Public buildingSpecial AreaResident AreaCBDHotelMall/SupermarketExhibition CenterAirport/Railway StationHigh-rise ApartmentMDUMiddle-rise ApartmentCommunityStadiumMetroCampus

The Importance of FDD-LTE Indoor CoverageIn LTE, the major service is data, to fulfill the coverage, capacity and quality requirements of which multiple and flexible coverage strategy has to be adopted . In addition, the preferable location to use data service is mainly indoor coverage area.The primary service provided by 2G is voice, whose strategy is wide coverage to resolve the issue on both coverage and capacity.CoverageCapacityCoverageCapacityQuality

Factor of Indoor Coverage Construction condition Conditions of cable layout and reconstruction Conditions of electricity Conditions of beautiful outlook and concealmentQuality of indoor signal Interference of the environment Users experienceAbility of upgrade Reconstruction of the network Ability of smooth upgradeCost of construction and maintenance Complexity and maintenance Low power consumption

Heterogeneous network: Mixed Macro, Pico, Femto, and DAS. Dense Urban Scenario 1 Macro BS solution satisfy high capacity requirementSub urban/Rural Scenariosolution fit for unbalanced large scale coverageIndoor ScenarioPico BS enhance the coverage in each floorDense Urban Scenario 2Outdoor Pico BS for hot-spot and weak signal areaRequirements for FDD-LTE Indoor CoverageMeet requirements of high speed data serviceScalable and upgradeable Low cost & Low power consumptionSmall size, portable, easy installationUnified O&M system, easy maintenance

Traditional Solution of Indoor CoverageOutdoor penetration coverage Macro eNodeBSignal source + Distributed antenna systemPassive distributed systemActive distributed systemFiber distributed systemRepeaterRadio repeaterFiber repeater

Macro cell is mainly for coverage and commercial showcase of LTE deployment. The real actual traffic and capacity will be provided with smaller cells for high dense area.

Outdoor Penetration CoverageThe macro eNodeBs signal to penetrate wallHigh penetration loss exists, the quality can not be guaranteedAccording to 3G construction experience, macro cell penetration coverage is not a good mobile broadband solution for indoor coverage.Micro eNodeB set closer to the coverage targetAbility to guarantee the indoor coverageIt will be existing high deployment cost as well as a hard way to get build out resources.Micro eNodeB penetration coverageMacro eNodeB penetration coverage< 10 floors or 30m65o~ 90 mMicro eNodeB

Signal Source + Distributed Antenna SystemHigh reliability, heavy workload, much restriction from buildingDifficulty with MIMO support and hard work to deploy the systemShould think about support multi-RAT. Passive distributed systemActive distributed systemTrunk amplifier helps to enlarge coverage, but it increases workloadHigh system complexityThe cascade number generally is no more than 3.

Micro eNB and RRU Indoor Coverage SolutionHigh power source + Distributed systemSuitable for medium or small scale buildingDepending on the IDS, not flexible for coverage expansionMicro RRU + Indoor Distributed SystemMicro eNodeB System + IDSMicroeNBMicroRRUBBU

Pico eNB NetworkingPico eNBAntennaSwitch routerSwitcher SwitcherAntennaPico eNB networking: Enhance indoor coverage in each floorPico

Pico RRU NetworkingPico RRU can be deployed directly with no need of distributed system for its small output power, which can improve the capacity and quality of indoor coverage obviously.New Building Coverage Sharing Macro eNodeBs CapacityHot spots & blind spots supplement

Distributed Antenna System RRUAntennaBBUDAS can improve the capacity and quality of indoor coverage obviously

Reuse Solution of Existing DAS Make the best of existing DASMIMO not supported2G BTS3G NodeBCombinerBDACouplerCouplerBDACouplerDividerDividerDividerDividerAntennaLTE BBULTE RRULTERRU

Indoor MIMO may bring data throughput improvement.Need to extend existing one antenna system to two at the similar positionOne RRU Port connects to combiner to use existing DAS systemAnother port connects to a new Distribute antenna system MIMO channel 2MIMO channel 1LTE RRUAntennaLTE BBUcombinerMIMO Supported3G NodeB

Femto eNodeBFemtoSwitch routerFemto eNB : Be suitable for family users

Femto eNodeB Network ArchitectureMME / S-GWMME / S-GWS1EPCE-UTRANEPSNo X2 interface support between femto eNodeBsFemto eNB gateway serves as concentrator on C- plane for many femto eNBsFemto eNB gateways are transparent and optionaleNodeBX2eNodeBFemto eNodeBS1Femto eNB GWFemto eNodeBFemto eNodeBFemto eNodeB

Various of Indoor Coverage Solution

LTE Indoor Coverage SolutionApplication ScenarioOutdoor eNode B penetration coverageLow capacity, small scale buildings, the requirements of coverage and traffic are lowTraditional Distributed SystemMedium capacity, Medium storey building and coverage area, allowed the RF cable construction, the office building, shopping mall where need to co-existing indoor coverage systemRepeaterLow capacity, less than 3 floor building, small coverage, isolated tunnel, villa, bar, etc.MicroMedium or small scale building where need to co-work with existing indoor coverage systemPico/Business FemtoHigh capacity, high storey building and coverage area, business center, shopping mall, business residence building and gymnasium where have large traffic but can not construct RF cable or indoor distributed systemFemtoHome access, FMC multi service convergence

Diverse Indoor Coverage SolutionsCapacityCoverageLowMiddleHighSmallMiddleLarge

FDD-LTE Indoor Coverage Analysis Indoor Coverage parameter Per antenna cover 50mCell edge SINR: 5dB (support 16QAM, can reach 5Mbps within 10 Resource blocks)Bandwidth: 20MHzeNB antenna gain: 2dB UE antenna gain: 0dBPenetration loss between walls: 8dB

FDD-LTE Indoor Coverage Analysis RS RE signal strength RS Noise figure: -174 + 10log(15kHz) + 9 = -123.2dBmCell edge SINR: 5dBRS RE signal strength: -123.2 + 5dB = -118.2dBm / 15KHz Indoor Path-loss calculationPath-loss model: L = 20log(f) + 30 log(d) - 28dBF = 2600MHz; d = 50mL = 91dB

FDD-LTE Indoor Coverage Analysis eNodeB Antenna port transmitter power RS RE signal strength: -118.2dBm/15KHzPath-loss: 91dBPenetration loss: 8dBeNodeB Antenna gain: 2dBReceiver-diversity gain: 3dBFading margin: 6dBRS RE transmitter power: -18.2dbm /15KHzAntenna port transmitter power: = -18.2 + 10log(1200) = 13dBm/20MHz

FDD-LTE Indoor Coverage Analysis Conclusion: Per antenna port transmitter power is about 13dBm. It can ensure good coverage and better performance in indoor environment.

FDD-LTE Indoor Antenna Configuration Antenna configuration for supporting MIMOIn order to support MIMO, two distributed antenna system must be supported.Another new distributed antenna system can be connected to combiner with existing antenna system.

FDD-LTE Indoor antenna configuration Indoor antenna configuration In order to support MIMO, lower channel correlation is required.Lower channel correlation is mainly determined by antenna configuration.

FDD-LTE Indoor Antenna Configuration Indoor antenna channel correlation Indoor environment produces rich multi-path;UE can receive various signals from antenna, wall reflection;The antennas with 0.5m to 1.5m lambda distance in BS is enough to produce low channel correlation.

FDD-LTE Indoor Antenna Configuration Indoor antenna configuration numbers More distributed antennas help to produce more multi-path and lead to lower channel correlation.For users located in cell-edge, more distributed antennas help to increase SINR.

1.5mBig RoomFDD-LTE Indoor Antenna Configuration Indoor antenna configuration numbers Scenario: Big room etcObvious LOS environmentNo reflector around UEAntenna distance 1.5m to ensure lower correlation

0.5mPassageIndoor Channel Correlation Testing Indoor antenna configuration numbers Scenario: Passage etcA Los path between BS and UE;A few reflectors around UE;Antenna distance 0.5m to ensure lower correlation.

Indoor Channel Correlation Testing Conclusion Normally, Lower channel correlation in indoor environment helps to use MIMO due to rich multi-path.For Big room environment, 1.5m BS antenna distance ensure lower channel correlation.For passage environment, 0.5m BS antenna distance ensure lower channel correlation.Antenna distance 0.5m to ensure lower correlation.

Requirement of Solution to meet DATA serviceBased on different criteria, ICIC can be divided into many categories. At present, we are only concerned about the scheduling of radio resources.Based on the lengths of scheduling periodBased on the methods of schedulingThe word methods here means different ways to reuse radio frequency bands*We will first take a look on the schemes based on scheduling period.*The enhancement of performance is at the price of complexity.**1PRB 0PRB 109PRB 1RNTP 0HII2X2LOAD INFORMATION RNTP

*Although it is possible to operate LTE systems with a universal frequency reuse plan, doing so can cause severe outage owing to interference, particularly along the inter-cell and inter-sector edges. To mitigate this, LTE allows for coordination of RB allocation to users at the cell edges such that there is minimal overlap. This allows for a more dynamic frequencyallocation across sectors, based on loading and interference conditions, as opposed to traditional fixed frequency planning. Those users under good SINR conditions will have access to the full channel bandwidth and operate under a frequency reuse of 1. Those in poor SINR conditions will be allocated non-overlapping sub-carriers such that they operate under a frequency reuse of 2, 3, or 4, depending on the number of non-overlapping sub-carrier groups that are allocated to be shared among these users. This type of sub-carriers allocation leads to the effective reuse factor taking fractional values greater than 1. The variety of sub-carrier allocation schemes supported by LTE makes it possible to do this in a very flexible manner. Obviously, the downside is that cell edge users cannot have access to the full bandwidth of the channel, and hence their peak rates will be reduced.*The message measurement report reported by UE includes RSRP information for severing cells and neighbor cells. If RSRPservering - RSRPneighbor < C1the UE is decided as cell edge user, otherwise, cell center user. RSRPservering is the RSRP for severing cell; RSRPneighbor is the RSRP for the best neighbor cell. C1 is the threshold in dB for CEU and CCU decision, which is adaptively adjusted with CEU proportionality.

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FDD LTE Indoor Coverage