Resonansfilter med justerbar filtermekanism

摘要

The present invention relates generally to filtering in e.g. mobile telephony. A new input loop is introduced wherein the input loop is fixed in its physical relation to the H-field. One end of this input loop is arranged to form a capacitance or an inductance which is then used to adjust the location of the maximum current node in the loop. The adjustment of the position of this maximum current node thereby adjusts the bandwidth of the RF signal. The fixing of the loop has the advantage of simplifying the procedure for tuning the filter. It also has the advantage of reducing the number of tools required for tuning, thereby allowing for a reduction in size occupied by the filter and isolator arrangement, and a reduction in the cabling and materials used.