Building on introductions from the 2016 NAB Show, the company has announced the addition of cross couplings to their manifold FM combiner filters.
Dielectric explains that the couplings allow “less frequency separation for combined channels. Since fewer cavities are used, efficiency is improved and operational costs are reduced.”
Dielectric Senior Engineer Derek Small said, “Higher-order filters have been required for channel combiners and IM reduction due to the crowded FM spectrum, and have a tendency to reduce efficiency … Higher order filters with large amplitude rolloff and delay can add asynchronous AM, and reduce stereo separation in the FM signal. From a classic design standpoint, the use of constant impedance FM combiners means twice as many filters and components and raise both initial and operational costs. Our new cross-coupled designs tackle these problems with much less complex architecture in shared FM facilities.”
NAB Show Booth: C2613