Non-Foster circuits for wideband and wide-angle scan in phased arrays

Contiguous collinear dipoles connected with non-Foster circuits (NFCs) was proposed for improving the bandwidth of arrays. Prior literature focused on use of ideal negative inductance and for broadside scan only. This paper presents results of a feasibility study to evaluate and characterize performance of dipole arrays loaded with non-Foster circuits in terms of VSWR, gain, bandwidth (L Ku band). The results show that NFCs help improve the scan performance and bandwidth in dipole based phased arrays. Stability analysis with the generalized Nyquist method could not identify a stable configuration for the NFC circuit itself covering the entire L Ku band.