Patent ID: 8536960

Claim:
A filter structure comprising: a first conductor layer, a second conductor layer spaced apart from the first conductor layer and substantially parallel to the first conductor layer, and a pattern in the first conductor layer with interconnected pattern elements and in each pattern element at least one high-impedance conductor strip with a length/area ratio such that an inductance seen by a longitudinal electric current in the at least one high-impedance conductor strip is dominant over a capacitance of the at least one high-impedance conductor strip against the second conductor layer, and a low-impedance conductive region where a ratio of an area of the low-impedance conductive region and a maximum diameter of the low-impedance conductive region is such that a capacitance of the low-impedance conductive region against the second conductor layer is dominant over an inductance of the low-impedance conductive region, wherein, in at least one of the pattern elements, the at least one high impedance conductor strip comprises at least two mutually adjacent first high-impedance conductor strips in a first direction, with first ends of the first high-impedance conductor strips arranged to connect directly to the low-impedance conductive region of the at least one pattern element, and the at least one high impedance conductor strip further comprises at least two mutually adjacent second high-impedance conductor strips in a second direction, with first ends of these second high-impedance conductor strips arranged to connect directly to the low-impedance conductive region, the first direction and the second direction being mutually intersecting, and wherein an electrical current path from the first ends of the first high-impedance conductor strips via the low-impedance conductive region to the first ends of the second high-impedance conductor strips is free from high-impedance conductor strips whose length/area ratio is such that an inductance seen by longitudinal electric current in the high impedance conductor strips is dominant over a capacitance of the high impedance conductor strips against the second conductor layer.