LTE Physical Layer

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presentation for implementation of lte physical layer it contatins a blocks and how each block is ?it may be also a good overview on revolution of mobile communication 2g, 3g, 4g.the physical layer is implemented using fpga and vhdl

Text of LTE Physical Layer

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LTE Physical Layer:Supervised By Prof AHMED YAHIA7/24/20111Prepared byAhmed Abdel-kader MahmoudAhmed Mahmoud Abdel-rahmanSabry Abdullah MohamedMahmoud Mohsen MohamedHesham Mohamed RefaatYaser Mohamd Osman7/24/20112AcknowledgementAny attempt at any level cannot be satisfactorily completed without the will of God and the support and guidance of learned people. We would like to express our immense gratitude to Dr. Ahmed Yahia for his constant support and motivation that has encouraged us to come up with this project.7/24/201133CONTENTSIntroduction.Mobile Communication Evolution.LTE Long Term Evolution.Physical Layer Implementation.VHDL.Simulation.Future work.Conclusion.7/24/20114Introduction To Mobile CommunicationCellular concept.Access techniques.Switching techniques.1st generation.Why 2nd generation ?

7/24/20115Cellular ConceptFrequency reuseReuse distanceIncreasing capacityClusters

7/24/20116Cell Types7/24/20117Multiple Access TechniquesCDMATDMAFDMA

OFDMAfff7/24/20118Switching techniques:Circuit SwitchingPacket SwitchingChannel for one userChannel for multiple usersOne pathMultiple pathFixed bit rateVariable bit ratBilling by timeBilling by volume Used for real time application Used for data transfer7/24/201191st generation features:Introduced to commercial uses in early of 1979 & late of 1980Analog technologyNot compatible system : such as American system (AMPS) uses 800 MHZ and Germany system (c450) used 450 MHZ so no roamingAccess technique (FDMA)Duplex technique (FDD) 7/24/201110Mobile Communication Evolutions7/24/201111GsmGlobal System For Mobile Communication

Features.Frequency band.Network architecture.

7/24/201112Features:

7/24/201113Features:

7/24/201114GSM frequency band: 890 MHz 915 MHz 935MHz 960 MHz Uplink Guard band Downlink Channel B.W= 200 KHz

carriers = 25 MHz / 200 KHz = 125 carrier 7/24/201115GSM Spectrum Allocation :CH 15432167001TimeCH 35432167001CH 25432167001CH 1245432167001Time slot = 0.577 msFrame duration = 0.577 ms * 8 = 4.616 ms7/24/201116Network Architecture GSMGMSCMSCEIRAUCVLRHLRBSCBSCOther PLMNsBTSBTSBTSBTSIWFSMC7/24/20111717GPRSGeneral Packet Radio Services:

Features.New services.Network Architecture.Network service area.

7/24/201118:Features

7/24/201119Features

7/24/201120Access techniques : TDMA/FDMA.Duplex techniques : FDD.Services offered

Always on internet access.Multimedia messaging service (MMS).Internet applications for smart devices through wireless application protocol (WAP).Point-to-point (PTP) service : inter-networking with the internet (IP).7/24/201121Network Architecture Of GPRSSGSNGMSCMSCEIRAUCVLRHLRGGSNBackbone NetworkIPIPNetworkBTS/BTS/BSC/PCUOther PLMNs7/24/20112222CDMACode Division Multiple Access Types Of Spread SpectrumPower Control

7/24/201123Types Of Spread SpectrumDirect sequence spread spectrumFrequency hopping spread spectrumTime hopping spread spectrum

7/24/201124Direct sequence spread spectrum

7/24/201125UMTSUniversal Mobile Telecommunication SystemFeatures.Frequency band.Network architecture.

7/24/201126UMTS Features7/24/201127UMTS Features7/24/201128UMTS Features7/24/201129Network Architecture UMTSSGSNGMSCMSCEIRAUCVLRHLRGGSNIPNetworkNode BNode BRNCCGFBilling SystemBTSBTSBSCNode BNode BRNCGSM BSSUTRANCore Network7/24/201130Long Term EvolutionLTE Specifications Frequency BandLTE TargetsLTE Network ArchitectureOrthogonal Frequency Division Multiplexing 7/24/201131LTE Specifications 7/24/201132LTE Specifications 7/24/201133LTE Specifications 7/24/201134LTE Frequency BandChannel bandwidth 5MHZ to 20 MHZ Bit Rate 100 Mbps up to 1 Gbps Sub carrier spacing 15 KHZ

2500MHz 2570MHz 2620MHz 2690MHz FDD Uplink TDD band FDD Downlink 15 KHZ7/24/201135LTE Network ArchitectureExternal networks:Operator services (e.g. IMS) and internetServices E-UTRANeNode BeNode BHSSPCRFP-GWS-GWMMEEPC7/24/201136LTE TargetsIncreasing User Throughput

Increasing Spectral Efficiency

Increasing Number Of Subcarrier

15 KHZ7/24/201137LTE TargetsDecreasing Latency FactorGSMUMTSLTE7/24/201138Basic channel access modesTransmitAntennasReceiveAntennasSISOThe Radio ChannelMISOSingle Input Single OutputMultiple Input Single Output(Transmit diversity)ReceiveAntennasTransmitAntennasMIMOThe Radio ChannelSIMOSingle Input Multiple Output(Receive diversity)Multiple Input Multiple Output(Multiple data streams)7/24/20113939MIMOTransmitting multiple data streams in the same space and time used to be called interference! So how does MIMO work?MIMO capacity gains come from taking advantage of spatial diversity in the radio channelThe performance can be optimized using precodingMultiple Input Multiple Output(Multiple data streams)7/24/201140OFDMAOrthogonal Frequency Division MultiplexingOFDM is a spectrally efficient modulation technique ,It is conveniently implemented using IFFT and FFT operations

Bandwidth W being divided into K sub-carriers, leading to carrier spacing f, satisfying f =W/K

Symbol duration T satisfying T = 1/f7/24/201141SC-FDMA

For the LTE uplink, a different concept is used for the access technique. Although still using a form of OFDMA technology, the implementation is called Single Carrier Frequency Division Multiple Access (SC-FDMA).One of the key parameters that affects all mobiles is that of battery life. Even though battery performance is improving all the time, it is still necessary to ensure that the mobiles use as little battery power as possibleSc-FdmaMulti Path Propgation7/24/201143Cyclic prefix insertion7/24/20114444FAST FOUREER TRANSFORM7/24/2011454 minutes30 seconds48 seconds1 second8 secondsLTE100 MbpsHSDPAWCDMAEDGEGPRSMobile technology competition7/24/201146Hard ware design 7/24/201147Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20114848DATA FORMATION10110100000000007/24/201149Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20115050Convolutional Encoder 00++InputOutput11c1c21011010100000000117/24/20115151 10++InputOutput10 c1c200110101000000001011Convolutional Encoder 7/24/20115252 01++InputOutput00 c1c21011010100000000101100Convolutional Encoder 7/24/20115353 10++InputOutput01 c1c21011010100000000101100010Convolutional Encoder 7/24/20115454 11++InputOutput10 c1c2001101010000000010110001010Convolutional Encoder 7/24/20115555 01++InputOutput00 c1c210110101000000001011000101000Convolutional Encoder 7/24/20115656 10++InputOutput10 c1c20011010100000000101100010100001Convolutional Encoder 7/24/20115757 01++InputOutput11 c1c200110101000000001011000101000011100000000000000000Convolutional Encoder 7/24/20115858Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20115959INTERLAEVER10110011000001117/24/201160INTERLAEVER10110011000001117/24/201161OFDM Transmitter7/24/201162Data formatConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Moduless/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And RxCP InsertionS/PIFFTp/s7/24/20116363OFDM TransmitterCP InsertionS/PIFFTS/P10100101p/s7/24/201164Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20116565OFDM ReceiverCP removal

s/pFFTS/P10110010101100107/24/201166Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20116767DE-INTERLEAVER101100110000011110101111011110107/24/201168Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20116969VITERBI DECODER000000a (00)b (01)c (10)d (11)11111101101010010111000000000000111111010101101010101010010101111111000000110110100111001101101001110011010010100011017/24/20117070

Viterbi decoder with error000000a (00)b (01)c (10)d (11)11111101101010010111000000000000111111010101101010101010010101111111000000110110100111001101101001110011010110100010011122132341343434344315444451335252456335252111100007/24/20117171Data formatCP InsertionS/PIFFTConvolutional Encoder Channel interfaceChannel ChannelinterfaceInterleaver Channel coding Modulesp/ss/pCP REMOVaFFTp/sViterbiDecoderDE- Interleaver Data deformatConvolutional Encoder OFDM Tx And Rx7/24/20117272 DATA DE-FORMATION10110100000000007/24/201173

VHDLVHSIC HardwareDescription Language7/24/201174VHDLs OrganizationThe basic VHDL model is known as a Design Entity and has two partsInterface - denoted by keyword entity defines I/O signals for the modelBody - denoted by keyword architecturedescribes how the model works7/24/201175VHDL (Xor) Exampleentity XOR2_OP is -- Input/Output ports port (A, B : in BIT;