3GPP

LTE RLC PDU Structure & Encoding

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In this tutorial the basic of LTE RLC PDU structure is discussed. The detail encoding of RLC PDUs will be discussed in the upcoming tutorials.

PDU Structure of TM, UM and AM Data and Control PDUs are described.

Flexible RLC PDU Size (Release 7)

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Flexible RLC PDU Size was interdicted in Release 7 in order to decrease RLC protocol overhead and to avoid sequence number stalling

Flexible RLC is used with MAC-ehs in Release 7. Mac-ehs is a new feature interdicted in Release 7 to increase the downlink throughput.

UMTS Radio Link Protocol Decoder

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UMTS-RLCDecoder is small but powerful tool for decoding RLC header information both for Acknowledged Mode RLC PDUs and Unacknowledged Mode RLC PDUs.

It Can decode the following

  • RLC AMD PDU Header and Length Indicator
  • RLC Control PDUs including SUFIs
  • RLC UMD PDU header and Length Indicator
Introduction to LTE

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LTE stands for Long Term Evolution. The LTE project was initiated in November 2004 and the focus was on enhancing the Universal Terrestrial Radio Access (UTRA) and optimizing the 3GPP’s radio access architecture.

The following areas are covered:

  • What is LTE?
  • 3GPP System Evolution
  • System requirements for LTE development
  • LTE System Architecture
HSUPA: High-Speed Uplink Packet Access

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High Speed Uplink Packet Access (HSUPA) is introduced in 3GPP Release 6 standards to improve the uplink UE data rate which was significantly low up to Release 5. To improve the uplink data rate some new functionality are added:

  1. New MAC entities: MAC-e/es in UE and MAC-e in NodeB and MAC-es in RNC.
  2. Transport channel: E-DCH
  3. Physical channels: E-DPDCH/DPCCH, E-HICH, E-RGCH, E-AGCH
  4. Transmission Time Interval: 2 ms or 10 ms
  5. SF = 2 can be used
  6. Fast Layer 1 transmission and retransmission
  7. Hybrid- ARQ using soft combining and incremental redundancies
  8. NodeB control grants or data rate
  9. New Frame Protocol in Iub/Iur interface (E-DCH FP)