[{"term":"Sub-THz","def":"Sub-terahertz frequencies (100–300 GHz). Candidate bands for 6G/7G offering massive bandwidth but limited range."},{"term":"THz","def":"Terahertz waves (0.3–10 THz). 7G targets these for 10+ Tbps links over short distances. Challenges: power efficiency and atmospheric absorption."},{"term":"Terahertz","def":"Electromagnetic waves in the 0.3–10 THz range. 7G research targets these frequencies for ultra-high-speed short-distance links."},{"term":"mmWave","def":"Millimeter wave (24–100 GHz). Used in 5G for urban hotspots. 6G will extend into higher mmWave bands with improved beamforming."},{"term":"OTFS","def":"Orthogonal Time Frequency Space — modulation using delay-Doppler domain. Better than OFDM for high-mobility scenarios (vehicles, drones)."},{"term":"OFDM","def":"Orthogonal Frequency Division Multiplexing — modulation used in 4G/5G. Splits data across narrow subcarriers. Sensitive to Doppler at high speeds."},{"term":"Open RAN","def":"Open Radio Access Network — disaggregates base station HW/SW into interchangeable multi-vendor components. Reduces costs and vendor lock-in."},{"term":"O-RAN","def":"Open Radio Access Network — disaggregates base station HW/SW into interchangeable multi-vendor components. Reduces costs and vendor lock-in."},{"term":"RAN","def":"Radio Access Network — the part between user devices and core network. Includes base stations, antennas, and signal processing."},{"term":"Beamforming","def":"Technique using multiple antenna elements to focus radio signals directionally. Essential at mmWave/THz frequencies."},{"term":"Massive MIMO","def":"MIMO with 64+ antenna elements. Enables spatial multiplexing — serving multiple users simultaneously on the same frequency."},{"term":"MIMO","def":"Multiple-Input Multiple-Output — uses multiple antennas to send and receive data simultaneously, improving capacity and reliability."},{"term":"Network Slicing","def":"Creating isolated virtual networks on shared infrastructure, each with different performance characteristics (latency, bandwidth, IoT)."},{"term":"ISAC","def":"Integrated Sensing and Communication — same signal for data transmission and radar-like sensing. Core 6G capability."},{"term":"RIS","def":"Reconfigurable Intelligent Surface — programmable reflective panels that redirect radio signals to extend coverage without extra base stations."},{"term":"Digital Twin","def":"Real-time virtual replica of a physical network. Simulates behavior before deploying changes — reducing outages and optimizing performance."},{"term":"AI-Native","def":"Network architecture where AI/ML is built into core functions (resource allocation, interference, security) from the ground up."},{"term":"NTN","def":"Non-Terrestrial Networks — satellite and HAPS components integrated with terrestrial cellular. Native in 6G architecture."},{"term":"HAPS","def":"High-Altitude Platform Station — unmanned aircraft or balloons at 20 km altitude providing wide-area wireless coverage."},{"term":"QAM","def":"Quadrature Amplitude Modulation — encodes data in amplitude and phase. Higher orders (1024-QAM) pack more bits but need cleaner signals."},{"term":"LDPC","def":"Low-Density Parity-Check — error correction code used in 5G data channels. Approaches the theoretical Shannon limit."},{"term":"Spectrum Sharing","def":"Dynamic allocation of frequency bands between operators or technologies. Replaces exclusive licensed spectrum with flexible approaches."},{"term":"vRAN","def":"Virtualized RAN — running base station functions on general-purpose servers instead of proprietary hardware. Enables cloud-native networks."}]