Hello, Nokia Gurus.
I`ve performed a trial with LTE2026: RRC Signaling Robustness - Downlink and got some good, but unexpected results. Your inputs and previous experiences are welcome!
The feature itself states that it can increase the SRB1 reliability by offering some configurable link adaptation offsets, which, in practical terms will increase or reduce the PDCCH aggregation level for SRB1. DL SRB1 traffic is about 0.1% of total DL traffic, as reference in this NW.
Based on NIB, this feature should keep at minimum the impact legacy Link Adaptation algorithms for PDCCH or PDSCH.
What I`m seeing and it is expected:
- reduction on SRB1 BLER (2 p.p.)
- increase on the average PDCCH aggregation level (2.5%).
What I`m seeing and it is NOT expected, especially in the magnitude of the change (remember, SRB1 traffic is 0.1).
A) reduction on the PDCCH control area size (9%).
b) reduction on the amount of samples with PDCCH using 3 symbols, the maximum (24%)
Sounds like in practice, the feature is impacting PDCCH link adaptation more than initially stated on NIB.
All feedback is appreciated, thanks!