Transmitting confidential data constellations that correctly synthesize only along the precise target angle, while projecting orthogonal artificial noise in all other directions.
ISACSecurity modulates phase and amplitude across antenna elements such that clean constellation points (e.g., 256-QAM) form exclusively along the intended receiver's azimuth and elevation. In all eavesdropping directions, constellations collapse into high-entropy noise.
The transmitter injects pseudo-random artificial noise into the null space of the legitimate receiver channel matrix. Eavesdroppers experience severe signal-to-interference-plus-noise ratio (SINR) degradation, driving secrecy capacity to theoretical upper bounds.