LAUSR

A novel ninth‐order suspended stripline low‐pass filter with three transmission zeros is presented. The technique uses a pseudo‐elliptic synthesis with grounding improvements and calculated element values for high rejection values. Suspended stripline low‐pass filters are most widely used for applications that require high suppression of spurious and harmonic signals, and grounding could affect stopband rejection. The designed low‐pass pseudo‐elliptic filter has a cutoff frequency of 2.5 GHz, an insertion loss of less than 0.5 dB, a stopband from 3.3 GHz to approximately 7 GHz with a rejection better than 60 dB, and a stopband from 3.1 GHz to 9 GHz with a rejection better than 50 dB.