Title :
Applications of Directional Filters for Multiplexing Systems
Author :
Coale, Franklin S.
fDate :
10/1/1958 12:00:00 AM
Abstract :
The design of microwave multiplexing systems for frequency channelization of a broad-band microwave spectrum is complicated by problems such as off-resonance mismatch and mutual interaction between adjacent filters. By employing directional filters as basic building blocks, it is possible to construct multiplexing filters with a perfect input match since the input VSWR of a directional filter is theoretically unity both at resonance and off-resonance. Less insertion loss of a manifold may be obtained by the use of directional filters than with conventional band-pass filters. Curves giving the predicted response of a manifold containing n elements are presented for single-tuned and double-tuned directional filters. An asymmetrical response shape is obtained which has a midband insertion loss related to the separation of adjacent channels. An experimental model consisting of a five-channel multiplexer has been constructed utilizing double-tuned-circular-waveguide directional filters.
Keywords :
Band pass filters; Damping; Filtering theory; Frequency; Impedance matching; Magnetic separation; Matched filters; Microwave filters; Performance evaluation; Resonance;
Journal_Title :
Microwave Theory and Techniques, IRE Transactions on
DOI :
10.1109/TMTT.1958.1125223