ISAC

ISAC is the idea that the same radio waveform can carry data and sense the physical world at the same time, the way radar does. Instead of running separate communication and sensing systems on separate hardware and spectrum, you design one waveform that does both, and the network gains the ability to detect, locate, and track objects as a side effect of communicating.

The economy of it is the appeal: spectrum and hardware are scarce and expensive, so reusing the communication infrastructure to also perceive the environment is efficient. The applications people get excited about include positioning without GPS, gesture and presence detection, drone and vehicle tracking, and feeding the network's own digital twin with a live picture of its surroundings. It's a flagship 6G research theme, but the engineering tension is real — a waveform tuned for high data throughput isn't automatically a good radar waveform, so ISAC is largely about finding designs that don't badly compromise either job.