In this type of system, each of the jamming antennas is acting as the signal source for a repeater- type jammer. In skirt jamming, the jammer exploits the phase response of filters in the radar receiver by injecting a strong jamming signal into a region just above or below the filter frequency.
Due to the bigger size, jamming pod often have bigger transmitting antenna and more power available compared to FOTD decoys and air-launched decoys, as a result, they have higher effective jamming power and better directivity ( gain ). At start, the jammer sends back an amplified version of the signal received from the radar.
The most common type of deception jammer is the range deception (range-gate stealer), whose function is to pull the radar tracking gate from the target position through the introduction of a false target into the radar’s range-tracking circuits. The relation between radar, jammer power, and jamming effectiveness is well known and easy to understand for most enthusiasts.
By contrast ,for support jamming the closer the jammer to threat radar , the easier it would be for the jammer to cover others assets because in this case aircraft reflection is not depend on the distance between the jammer and the threat radar so getting the jammer closer to the radar is better.
Non-Cooperative Target Recognition (NCTR ) techniques such as jet-engine modulation used by modern radar (most radars after 1980s) can distinguish decoys from real aircrafts. Against a conically scanning tracking radar, an inverse gain repeater jammer has the effect of causing positive feedback, which pushes the tracking radar antenna away from the target rather than toward the target.