Filter Designer Mobile app for iPhone and iPad

This application enables the rapid design of RF and Microwave, low-pass, high-pass, band-pass and band-stop filters in Butterworth, Chebyshev and Bessel configurations. Lumped-element, coupled line, stepped impedance or capacitive gap implementations are supported, depending on the configuration. Full schematics of each design are automatically generated, and an S-parameter analysis is performed on the filter design. S21 and S11 are presented in dB over frequency, as well as S21 phase and group delay. Although developed as a microwave application, the filter design procedure is suitable for use at lower frequencies as well.