Working of outer loop link adaptation (OLLA) based on BLER in 5G

Hello,

I would like to to understand the exact working of the outer loop link adaptation in 5G whereby the MCS is adjusted to track the configured BLER target.

Thee following resources from NetSim seem to suggest that BLER is calculated at a TB level (not CB level) and is only computed on initial transmissions.

  1. 5G NR - NetSim Help Centre
  2. Plotting BLER vs time in NetSim : NetSim Support Portal

In other words, init BLER (and not the final or residual BLER) is adjusted to meet target BLER. Is this accurate? Are there any other good resources explaining the nuances of how OLLA-BLER works in 5G?

Thanks