lte ppt
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Long Term Evolution -A Communication Standard
Mobile broadband is becoming a reality.
It is estimated that 1.8 billion people will
have broadband by 2012.
Majority of these are served by HSPC.
Replacing HSPC by LTE, the user experience would
be even more better.
OVERVIEW
Latest 3GPP standard.
Downlink speed up to 150 Mbps.
Uplink speed up to 50 Mbps.
Provide apps like Interactive TV, Voice over
IP, Streaming multimedia, MMOG and
much more.
LTE
Goals of LTE
Data rate
Throughput
Latency
Bandwidth
Interworking
MBMS
Cost
Mobility
Single Carrier Modulation and Channel
Equalization.
Orthogonal Frequency Division
Multiplexing (OFDM).
Single Carrier Frequency Domain Multiple
Access (SC-FDMA).
BASIC CONCEPTS
SC modulation introduces Multipath
Distortion.
Single Carrier Modulation
Results of Multipath distortion
Results of Multipath distortion
Two methods of Channel Equalization:
1. Channel Inversion
2. Rake Equalization
Channel equalizer implementation
becomes increasingly complex as data
rates increase.
Channel Equalization
Equalizer Topology
OFDM - Transmitter
OFDM - Receiver
Elimination of ISI
SC-FDMA
Radio Access Network Architecture
Radio Protocol Architecture
Architecture
Radio Access Network Architecture
Radio Protocol Architecture
Block Diagram
Coding and Modulation
Resource Mapping
Multi-Antenna Transmission
Downlink Transmission Scheme
Block Diagram
Cyclic Redundancy Check (CRC)
Channel Coding, Rate Matching, and HARQ
Interleaving
Modulation
Coding and Modulation
Resource Mapping
Multi-Antenna Transmission
Spatial Multiplexing
Spatial Multiplexing
with CDD
Beamforming
Beamforming with
CDD
Transmit Diversity
Block Diagram
Coding and Modulation
Resource Mapping
Multi-Antenna Transmission
Uplink Transmission Scheme
Block Diagram
Cyclic Redundancy Check (CRC)
Channel Coding, Rate Matching, and HARQ
Interleaving
Modulation
Coding and Modulation
Resource Mapping
LTE is more of a revolution than an evolution.
Wider bandwidths, multicarrier modulation,
multiple antennas and packet scheduling are
the technologies finding exploitation in LTE.
Researches are going on to upgrade LTE as
‘LTE-ADVANCED’.
LTE-Advanced are challenging, both in terms
of the timescale and expected data rates and
performance.
Beyond LTE
Designed to operate in scarce and valuable
licensed spectrum.
Well positioned to meet the requirements of next-
generation mobile networks.
High performance, mass-market mobile
broadband services, through a combination of high
bit-rates and system throughput – in both the
uplink and downlink – with low latency.
Conclusion
LTE enabling technologies – OFDM
• R. van Nee and R. Prasad, OFDM for Wireless Multimedia Communications,
Artech House, 2000. – SC-FDMA
• H. G. Myung et al., “Single Carrier FDMA for Uplink Wireless Transmission,” IEEE
Vehicular Technology Mag., vol. 1, no. 3, Sep. 2006.• http://hgmyung.googlepages.com/scfdma
References and Resources
3GPP LTE – Spec
• http://www.3gpp.org/ftp/Specs/html-info/36-series.htm• http://www.3gpp.org/ftp/Specs/html-info/25814.htm (old)
– E. Dahlman et al., 3G Evolution: HSPA and LTE for MobileBroadband, Academic Press, 2007
– H. Ekström et al., “Technical Solutions for the 3G Long-TermEvolution,” IEEE Commun. Mag., vol. 44, no. 3, March 2006, pp.38-45
– 3G Americas, “Mobile Broadband: The Global Evolution ofUMTS/HSPA - 3GPP Release 7 and Beyond" available at
http://www.3gamericas.org/pdfs/UMTS_Rel7_Beyond_Dec2006.pdf
– http://www.LTEwatch
References and Resources
tTHANK YOU
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