On the synthesis of bandpass filters with bridged topology

This paper presents a general design theory for bridged topology filters exhibiting a Chebyshev characteristic within any wide passband and an arbitrary out-of-band response. The networks proposed consist of LC grounded resonators capacitively coupled to each other. All the inductances have the same value and also negative couplings may be realized by using 1:-1 transformers. One of the most interesting applications is the design of an FDM channel filter working in the 24-28-kHz range. Some experimental results are described.