Update to ns-3.36.1, bug fixes and general improvements
This release updates the baseline ns-3 to the version 3.36.1, thus introducing the new CMake-based build system in place of Waf.
Moreover, various fixes and improvements such as:
- Moving the NR frame number variable from uint16_t to uint32_t, to support longer simulation times;
- Assuming 12 OFDM symbols to estimate the TB error probability in the CQI determination procedure, as specified in Sec. 5.2.2.5 of TS 38.214
have been introduced.