ALK Engineering: Filter Design: Passive radio frequency filters, LC, comb-line, and interdigital. Offers two industry-standard filter design programs, and a freeware program for coil design.
Electrical Engineering Software: Filter design software, microwave, RF, active OP-Amp filters.
FILPRO: Microwave and RF filter and multiplexer design software. Provides detailed information about the product.
Filter Solutions: Software solutions for passive, active, Tx line, IIR, and FIR filter design, synthesis, and analysis.
OMICRON: Specializes in filter design software tools and consulting foractive, passive, and digital electronic filters. Description of company and presentation of the software. Download possible.
Schematica Software: Filter design software for electronics engineers and technicians. Filter Wiz for active filter design; OpFil for both passive and active filter design.
Tyder Ltd: Provides digital filter design software which can produce specialised filters e.g. Windowed FFT, Optimal FIR filters, and IIR filters.