VRTSIM enables end-to-end RAN testing without physical RF hardware.
By replacing the SDR with a real-time virtual radio link, teams can develop, tune, and regression-test network configurations entirely in software while preserving realistic timing and channel behavior.

Within OAI’s O-RAN stack, VRTSIM can replace a physical SDR such as a USRP on the RF-facing side of the O-RU. When combined with OAI’s DPDK-accelerated implementation of the O-RAN 7.2x split, this approach allows teams to validate the complete O-DU-to-O-RU chain over eCPRI before introducing radios, antennas, or RF test benches.

VRTSIM provides three complementary channel-simulation paths: built-in models—including AWGN, Rayleigh, Rician, EPA/EVA/ETU, and 3GPP TDL-A through TDL-E—for controlled and repeatable testing; the CIRDB engine for time-evolving mobility scenarios; and the taps_client interface for streaming live channel impulse responses from external emulators, ray tracers, or digital twins over nanomsg.

From standardized lab tests to high-fidelity, scenario-specific channel emulation, VRTSIM provides an open and cost-effective software environment for realistic and repeatable RAN validation.