5G-LENA ns-3 nr module

This release is compatible with ns-3.40.

Remember to follow the instructions from the README.md file, i.e., to checkout the correct release branch of both, ns-3 and the NR module. The information about compatibility with the corresponding ns-3 release branch is stated in the README.md file.

New user-visible features

This NR release comes with the first NR module tutorial created by Giovanni Grieco in the scope of GSoC 2023 project IUNS-3 5G NR: Improving the Usability of ns-3's 5G NR Module mentored by Tom Henderson, Katerina Koutlia, and Biljana Bojovic. This tutorial focuses on a cttc-nr-demo example and explains the internal functionality of the NR RAN by providing a detailed, layer-by-layer insights on the packet lifecycle as they traverse the RAN. The tutorial highlights all the points in the NR protocol stack where packets may be delayed or dropped, and how to log and trace such events.

Overall enhancement of the logging in the NR module. For many log messages the log level is refactored to provide easier overall logging, which allows to focus on the main events in the RAN protocol stack. In many places the logging information is expanded and improved its comprehension.

Added Tx and Rx trace sources in NrNetDevice to allow easier tracing of the events when the packet is transmitted or received.

The references in the examples are updated to point to the latest 3GPP documents.

Bugs fixed

• #157 Changed default value of NumHarqProcess to 16.
• #166 Avoid Time overflow in nr-ch-access-manager.cc.
• Fixed to use NS_LOG_FUNCTION instead of NS_LOG_INFO for function calls.