signalling event

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A transmitter encodes data by producing a signal which is a continuous stream of signalling events each which has sufficient information for the receiver to recover the original data. Just like a quantum leap is the smallest measurable leap, a signalling event is the smallest possible amount of signal that the receiver needs to recover the original data without error.
• noun telecommunications A change of the state of a communication channel, each state representing a symbol that is to be transmitted.