Hybrid Folded Rectangular Waveguide Filter

Description

A waveguide filter is an electronic filter that allows signals of certain frequencies to pass through while rejecting signals of other frequencies. This type of filter is used in order to filter signals of microwave frequencies and they are commonly employed in satellite communications and radio & TV broadcasts.

The filtering elements of the waveguide filter, which usually have the form of a metal tube, are waveguide resonators. Depending on the use, these waveguide resonators are stacked together in order to form the filter.

The invention relates to a group of resonators that can be used in rectangular waveguide filters and it offers a novel design that reduces the size of the filter while increasing the performance.

Innovations and advantages

One important advantage of this invention is that it reduces the area occupied by the filter. This is very important in mobile and space applications because the available area is very limited.

Additionally, the invention allows the implementation of more complex transfer functions in technical applications where such microwave filters are used.

These advantages are achieved while keeping the manufacturing of the rectangular waveguide filter simple and inexpensive.

In the past other approaches proved to be effective in implementing more complex transfer functions but they failed in reducing the footprint of the filter. These approaches either added additional resonators or the filter structure was folded in the horizontal plane and as a result the footprint of the resulting microwave filter was increased.   

Commercialisation aspects

This technology can be applied to microwave filters in satellite communications and more specifically in the front end of ground and satellite payloads (telecommunication, radars, Synthetic Aperture Radar (SAR), radiometers, radiolinks, etc..)

It can also be used in telephone networks and in television broadcasting.