Paper on Terahertz-Band ISAC Receives Coveted IEEE Mimno Award

The next generation of wireless, 6G, moves beyond raw data rates to embed sensing directly into the communication link. Integrated Sensing and Communications (ISAC) re‑uses the same terahertz‑band radio waves as a radar, promising sub‑millimeter mapping while delivering 100 Gbps links. Yet terahertz frequencies sit between microwaves and infrared, where water vapor creates sharp transmission windows and up to 120 dB path loss over 100 meters. Beam split—different frequencies diverge like a prism—and extreme Doppler shifts for fast devices pose fundamental reliability hurdles.

Engineers are turning those physics problems into advantages. Ultra‑massive antenna arrays are organized into sub‑array groups, cutting power consumption about 200‑fold versus fully connected designs. Graphene‑based plasmonic nano‑antennas add electronic tunability, enabling beam steering without bulky phase shifters. The expanded near‑field—up to 40 meters at 0.6 THz—creates spherical wavefronts that focus energy at a specific range, delivering true 3‑D beamforming and reducing interference. Intelligent reflecting surfaces act as programmable mirrors, redirecting blocked beams and reclaiming up to four decibels of gain.

Because the network must adapt to blockages and mobility, conventional optimization is too slow. Edge AI with federated learning lets each device train local models on raw radar data and share only compressed updates, slashing communication overhead twelvefold while preserving privacy. High‑speed vehicular scenarios remain tough; Doppler shift at 0.3 THz is ten times worse than at 30 GHz, breaking OFDM orthogonality. Ongoing work targets robust waveforms and adaptive beam‑split compensation, aiming to make terahertz ISAC viable for indoor ultra‑fast broadband and future autonomous‑vehicle ecosystems.