What is the Adaptive Modulation and in which scenario do we have to use it?

  • We have 2 types of modulation:

    • Fixed modulation
    • Adaptive modulation
  • In Fixed modulation we set the microwave link to operated on specific modulation order

    • For example 265 QAM
  • In adaptive modulation we set and configure the microwave Link to operate on range of modulations

    • For example minimum modulation will be 128 QAM and maximum modulation will be 1024 QAM
    • In that case the link will change the modulation order according to the change happening in the channel condition.
  • Channel condition means the power level and bot errors and signal to noise ratio.

  • Important formula : as the channel condition become better, the modulation can reach the maximum.

  • In case the channel condition become worse, the Link will downgrade the modulation to recover the data.

  • As modulation order increasing, the data rate increasing and the bot errors also increasing

    • And vice versa
  • We have to use adaptive modulation with Ethernet traffic and fixed modulation with SDH PDH traffic

Credits: :point_down: