Support for large DU delay profiles

[khooi8913]

This patch introduces necessary changes to xRAN to support large DU delay profiles. The key changes involved are related to the C-plane packet generation logic. Note that the NB-IOT conditional branch is not tested given that it is not used at the moment, and it is thus intentionally left for future work.

[arora-sagar]

@rorsc @teodora-vladic please review

[rorsc]

@rorsc @teodora-vladic please review

maybe @bpodrygajlo would be better here.

[teodora-vladic]

I have just tested the following and works E2E:

• 4x4 9b 100MHz with short/long PRACH format
• 4x4 16b 100MHz with short PRACH format
• 8x8 9b 100MHz with/without DAS, and short PRACH format

Thank you @khooi8913 for the contribution. Regarding the compatibility with ProtO-RU, which parameters shall be adapted in the reference config file https://github.com/duranta-project/openairinterface5g/blob/develop/targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.106prb.fhi72.1x1-proto-ru.conf?

[khooi8913]

I have just tested the following and works E2E:

• 4x4 9b 100MHz with short/long PRACH format
• 4x4 16b 100MHz with short PRACH format
• 8x8 9b 100MHz with/without DAS, and short PRACH format

Thank you @khooi8913 for the contribution. Regarding the compatibility with ProtO-RU, which parameters shall be adapted in the reference config file https://github.com/duranta-project/openairinterface5g/blob/develop/targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.106prb.fhi72.1x1-proto-ru.conf?

Hi @teodora-vladic , two changes are needed:

1. for the DU, raise sl_ahead from to >= 11.
2. for ProtO-RU, raise T2a_max_cp_ul to 2985 -- all counters should be on time now.

Let me know if it works for you -- thanks!