standoff transmitter
It is one of the technique in sniper mode.
If an aircraft is approaching the hostile range. Hostile defense systems can detect the signals coming from the aircraft radar, assumed aircraft is operating in tx and rx modes.
if the aircraft is not operating tx mode but only Rx mode. this case Tx is supported by the standoff transmitter present either in air or land.
"penetrating aircraft with a silient receiver" means aircraft approaching hostile environment silently.