Inband scattering from arrays with series feed networks

Approximate equations are presented for the radar cross section (RCS) of a phased array antenna with a series feed beamforming network. The incident radar wave is assumed to be at the same frequency as the antenna operating frequency. In deriving the RCS formulas, multiple reflections are neglected, and like devices in the feed are assumed to have identical transmission and reflection coefficients. The approximate results are shown to be in excellent agreement with results obtained using a scattering matrix approach. The behavior of the RCS as a function of several feed design parameters is also investigated