telecom • networking • design

an EventHelix.com blog


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LTE Physical Layer Introductory Videos

Learn about the LTE physical layer from the video series from IEEE and Ericsson. Th video series covers:

  1. LTE protocol structure and architecture
  2. Downlink frame structure, reference signal and MIMO
  3. Downlink control signaling
  4. Uplink SC-FDMA, reference signals and control signaling
  5. TDD and half duplex FDD
  6. Transmission procedures
  7. Cell search, SI and random access procedures

LTE multi antenna transmission


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OFDM and SC-FDMA lectures

OFDM and SC-FDMA video lectures cover OFDM and SC-FDMA is great detail. The following topics are covered:

  • OFDM and multi-carrier modulation
  • Converting a frequency selective channel to a flat fading channel
  • IFFT based multi-carrier modulator bank
  • FFT based multi-carrier demodulator bank
  • Cyclic prefix and circular convolution
  • MIMO OFDM
  • PAPR in OFDM
  • SC-FDMA reduces PAPR

OFDM transmitter schematic

OFDM receiver schematic

Click here to view the OFDM and SC-FDMA lectures


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LTE Video Presentations

OFDM Time Frequency Multiplexing

Rohde & Schwarz‘s presentations provide an excellent introduction to LTE. The presentations are accompanied with an audio narration. The topics covered are covered:

  1. LTE Introduction
    • Motivations for LTE
    • LTE market and background
    • Requirements
    • Evolution path to LTE
  2. LTE Parameters and Downlink Modulation
    • LTE parameters and frequency bands
    • What is OFDMA?
    • OFDMA multiple access and downlink frame structure
    • OFDMA transmit and receive chains
  3. OFDMA and Downlink Frame Structure Details
    • Downlink OFDMA time-frequency multiplexing
    • LTE Spectrum Flexibility and Bandwidth
    • FDD downlink frame structure detailed
    • TDD frame structure
  4. SC-FDMA and LTE Uplink
    • Introduction to SC-FDMA and uplink frame structure
      • Marriage of single carrier transmission and FDMA
    • Uplink SC-FDMA tranmsit and receive chains
    • Peak to Average Power Ratio (PAPR) comparison with SC-FDMA and OFDMA
  5. Network and Protocol Architecture
    • LTE/SAE network architecture
    • EPC -Evolved Packet Core
    • Base Station control plane and user plane protocol stacks
    • EPC protocol stacks
  6. Channel Mapping and UE Categories
    • Logical and transport channel mapping in downlink and uplink
    • LTE UE Categories
  7. Initial Cell Search and Cell Selection
    • Downlink physical channels and signals
    • Cell Search and Selection in LTE
      • Primary synchronization signal
      • Secondary synchronization signal
      • Reference signals
  8. System Information
    • Downlink reference signal details
    • Master Information Block on PBCH
    • System Information on DL-SCH
  9. Random Access Procedures and EPS Bearer Setup
    • Random access preamble transmission to eNodeB
    • Random access response from eNodeB
    • Resource allocation and contention resolution
    • Signaling on PDCCH
    • Hybrid ARQ
    • RRC Connection Setup and EPS Bearer Setup
  10. Uplink Channels and Signals
    • Uplink physical channels and signals
    • PU-SCH: Physical Uplink Shared Channel
    • Uplink assignment signaling on PDCCH
    • Uplink frequency hopping
    • PUCCH
  11. LTE Mobility and MIMO Introduction
    • Intra MME Handover over the X2 interface
    • RRC States
    • MIMO Basics
      • Transmit diversity
      • Spatial multiplexing
      • Beamforming
  12. Downlink and Uplink MIMO in LTE
    • Downlink MIMO modes
      • Transmit diversity
      • Spatial multiplexing
      • Cyclic delay diversity
      • Beam forming
    • Spatial multiplexing downlink transmitter chain
      • Code book based precoding
    • Uplink MIMO
      • Uplink transmit antenna selection
      • Multi-user MIMO
  13. eNodeB and UE Performance Requirements
    • eNodeB modulation quality measurements
    • eNodeB performance requirements
    • UE performance requirements
  14. UE Certification and Field Trials
    • LTE terminal testing stages
    • LTE terminal certification
    • LTE field trial scenarios


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LTE and WiMax Tutorial

Detailed presentation that covers the following topics:

  • Fundamental constraints from the Shannon Limit
  • Multipath radio propagation
  • Time varying multi-path channel
  • Cellular systems and frequency reuse
  • 4G enabling technologies
    • OFDM/OFDMA
    • SC-FDMA
    • MIMO
    • Fast channel-dependent scheduling
    • Fractional frequency reuse
  • OFDM
    • Orthogonal sub-carriers
    • OFDM implementation using DFT
    • Cyclic Prefix
    • Frequency Domain Equalization
  • SC-FDMA
    • Subcarrier mapping
    • SC-FDMA is DFT precoded OFDMA
    • PAPR characteristics
  • MIMO
    • Spatial diversity
    • Spatial multiplexing
  • Channel dependent scheduling
    • Select channels based on users signal quality in the resource grid
  • LTE specifications
    • Network architecture
    • Frame structure
    • Resource grid
    • Bandwidth configuration
  • LTE physical channels
  • LTE transport channels
  • LTE logical channels
  • Downlink physical channel processing
  • Uplink physical channel processing
  • Random access
  • LTE Advanced
    • Channel aggregation
    • Enhanced MIMO
  • WiMax