{{Short description|Time for a receiver or transmitter to respond to a signal}} {{Use dmy dates|date=October 2023}}
In telecommunications, '''attack-time delay''' is the time needed for a receiver or transmitter to respond to an incoming signal.
For a receiver, the attack-time delay is defined as the time interval from the instant a step radio-frequency signal, at a level equal to the receiver's threshold of sensitivity, is applied to the receiver input, to the instant when the receiver's output amplitude reaches 90% of its steady-state value.<ref name=FS1037C>Federal Standard 1037C</ref> If a squelch circuit is operating, the receiver attack-time delay includes the time for the receiver to break squelch.
For a transmitter, the attack-time delay is defined as the interval from the instant the transmitter is keyed-on to the instant the transmitted radio-frequency signal amplitude has increased to a specified level, usually 90% of its key-on steady-state value.<ref name=FS1037C/> The transmitter attack-time delay excludes the time required for automatic antenna tuning.
==See also== *Transmit-after-receive time delay *Receive-after-transmit time delay
==References== {{reflist}} {{FS1037C MS188}}
Category:Telecommunications engineering Category:Radio technology