Dual-Channel Void Encoding (DCVE)Every digital signal contains two independent physical degrees of freedom: the bit values (0s and 1s), and the durations of the gaps between signal transitions termed void intervals. This invention encodes a second, independent message in those gap durations simultaneously with the primary bit stream.The encoding method Binary Duration Modulation assigns a short gap duration to secondary bit '0' and a long duration to secondary bit '1'. The secondary message is mathematically invisible to any decoder observing only signal values, including conventional