LTE-Advanced Pro (4.75G) — Rel-13, Rel-14 (2016-2017)
Pre-5G evolution with License Assisted Access (LAA) for unlicensed spectrum, NB-IoT and LTE-M for massive IoT, V2X for vehicular communication, and Massive MIMO/FD-MIMO.
LTE-Advanced Pro bridges 4G and 5G technologies. Standardized in Rel-13 (2016) and Rel-14 (2017), it introduced key innovations for IoT and vehicular communications.
License Assisted Access (LAA) enables LTE in unlicensed 5 GHz spectrum, combining licensed anchor carriers with unlicensed secondary carriers using Listen-Before-Talk.
NB-IoT provides ultra-narrow bandwidth (180 kHz) connectivity for low-power sensors and trackers, while LTE-M (eMTC) offers higher bandwidth for wearables and industrial IoT with VoLTE support.
V2X (Vehicle-to-Everything) enables direct communication between vehicles, pedestrians, and infrastructure for road safety and autonomous driving use cases.
Massive MIMO / FD-MIMO (Full Dimension MIMO) uses large antenna arrays (up to 64 ports) with 3D beamforming for significantly improved capacity and coverage.