Broadband Dolph-Chebyshev Array Synthesized by Slow-Wave Transmission Line

A broadband, low sidelobe level (SLL), microstrip array excited with a Dolph-Chebyshev distribution that is implemented with a periodic-stub loaded slow-wave transmission line (SW-TL) feed network is presented. The desired Dolph-Chebyshev excitation of the uniformly spaced microstrip array is achieved simply by modulating the widths of the stubs along the SW-TL feed network. Simulated results demonstrate that the array is low profile, 0.023λ0 in height, has a broad fractional bandwidth, 9.7%, and exhibits SLLs as low as -30dB.