pdf_gross.gifAMR in GSM - Operation, Procedures & Testing

[2-day course, Euro 2,350.- (net) per participant]

backtotop.gifAdaptive Multirate Encoding in GSM-Networks

Course Description

  • Speech Transmission in GSM
    Restrictions of Transmission Systems, Bit rates, Basic channels, Transcoding, Forward and backward error correction
  • GSM Full Rate Speech Coder
    Linear Predictive Coding, Long Term Prediction
  • GSM Speech Codec Family
    Full Rate, Half Rate, Enhanced Full Rate
  • Transmitter Speech Functions
    DTX, Voice Activity Detector, Silence Descriptor
  • Receiver Speech Functions
    Comfort Noise generation, Replacement of erroneous speech frames
  • Discontinuous Transmission
    Background Noise Parameters, Hangover
  • Mean Opinion Score
    Acceptability of speech quality, Test and summary of results
  • Future Requirements on GSM Speech Codecs
    Quality improvements, Optimization of Air-Interface
  • Channel Adaptive Speech Codec
    Quality dependent adaptation

backtotop.gifControlling the AMR Operation

  • Set-up procedures for AMR
    Initial codec-mode selection, Inband Signaling, Codec mode adaptation
  • Overview of level 3 and inband signaling procedures
    Level 3 signaling, Frequent inband signaling, Robust less frequent inband signaling
  • AMR configuration modification
    Level 3 signaling, Frequent inband signaling, Robust, less frequent inband signaling
  • AMR in Radio Resource Management (layer 3 signaling)
    AMR configuration parameters, RR-messages with AMR configuration parameters, The Multi Rate Configuration IE and the initial AMR set-up, Threshold and Hysteresis values, Example for Codec Mode transitions during Handover
  • Codec mode adaptations and inband signaling in MS, BTS and TRAU
    Comparison of Tandem Operation with TFO, Concept of TFO, Mobile to PSTN call, Mobile to Mobile in Tandem Operation, Mobile to Mobile call in Tandem Free Operation
  • Codec mode adaptations and inband signaling in MS, BTS and TRAU in TFO (Tandem Free Operation)
    Procedure for downgrading of codec modes in TFO, Procedure for upgrading of codec modes in TFO
  • CMI phase
  • Robust, less frequent signaling in AMR

backtotop.gifChannel Coding Procedures for AMR

  • Overall functions and sequence of channel coding and decoding
  • Tasks of the channel coder in AMR
  • The convolutional coder
  • TCH/AFS (Adaptive multi rate channel, Full rate, Speech)
    Speech frame channel coding AFS, Channel coding of RATSCCH and the SID_UPDATE frames, Channel coding of SID_FIRST frame, Channel coding of the ONSET frame
  • TCH/AHS (Adaptive multi rate channels at Half rate, Speech)
    Speech frame channel coding AHS, Channel coding of the RATSCCH frame

backtotop.gifTesting of AMR

  • Test strategy
    Speech quality tests, test location and conditions, Mean Opinion Score, examples