Extending the ns-3 O-RAN Module with Native 5G New Radio Support

Abstract

The ns-3 O-RAN module released by the National Institute of Standards and Technology (NIST) provides a fully simulated Near-Real-Time RAN Intelligent Controller (Near-RT RIC) but supports only the Long Term Evolution (LTE) stack. This work presents an extension that adds a complete, symmetric 5G New Radio (NR) data plane: NR E2 node terminators, cell-info, Reference Signal Received Power / Reference Signal Received Quality (RSRP/RSRQ), Signal-to-Interference-plus-Noise Ratio (SINR), and gNB Measurement Report reports and reporters, the last preserving the quantization and event identity of the 3GPP Radio Resource Control (RRC) Measurement Reports the gNB receives, an NR handover trigger and command, new data-repository methods backed by six SQLite tables, seven NR-native Logic Modules, an inter-Radio Access Technology (inter-RAT) Logic Module that drives Non-Standalone E-UTRA-NR Dual Connectivity (NSA EN-DC) Secondary Cell Group (SCG) decisions, and NR-aware extensions to both upstream Conflict Mitigation Modules (CMMs). Two of the Logic Modules reproduce, at the RIC, the decisions of the standard Event A2/A4 and Event A3 gNB handover algorithms by consuming quantized RRC Measurement Reports, so that hysteresis and time-to-trigger remain where 3GPP puts them. We also validate the feasibility of ML integration by training an example classifier on a short history of NR RSRP differences and executing it via ONNX Runtime to drive NR-to-NR handovers during simulation, where the learned model internalises the dwell requirement the standard enforces as a time-to-trigger.