Anti-radiation missile was achieved by the SAM site's radar receiver locking on to radio noise emissions generated by an aircraft's jamming pod. In cases of heavy jamming, missiles were often launched exclusively in this mode; this passive tracking meant that SAM sites could track targets without needing to emit any radar signals, and so American anti-radiation missiles could not be fired back in retaliation. Recently, the People's Republic of China developed the FT-2000 system to counter AEW and AWACS targets. This system is based on the HQ-9, which is in turn based on the S-300PMU. These anti-radiation missile systems have been marketed
A-135 anti-ballistic missile system 350 km and altitudes of 50 km. A-135 anti-ballistic missile system The A-135 (NATO: ABM-3 Gorgon) anti-ballistic missile system is a Russian military complex deployed around Moscow to counter enemy missiles targeting the city or its surrounding areas. It became operational during 1995. It is a successor to the previous A-35, and complies with the 1972 Anti-Ballistic Missile Treaty. The A-135 system attained "alert" (operational) status on February 17, 1995. It is operational although its 51T6 (NATO reporting name: SH-11) component was deactivated in February 2007. A newer missile (PRS-1M) is expected to replace it. There is an operational test