Abstract: Disclosed are apparatus and methods for determining a radar cross section (RCS) of countermeasure units such as chaff that utilizes ground level testing. An antenna platform is provided that is mounted to a support member at ground level and includes a radar transmit antenna disposed on the antenna platform, a radar receive antenna disposed on the antenna platform, and radar attenuating material disposed on the antenna platform linearly between the transmit antenna and the receive antenna for attenuating linear transmission of signals between the transmit antenna to the receive antenna. Additionally, low power transmitters used to enable safe ground testing are coupled to the transmit antenna for transmitting radar RF signals toward dispersed countermeasure units above the platform and also network analyzers coupled to the receive antenna that are capable of measuring the low power RF signals reflected by the dispersed countermeasure units.