Controllable center frequency, multiple transmission zeros (TZs), compact dual-band bandpass filter (DBBPF), patterned suspended substrate (SISL), self-packaged.

To reduce the conductor loss, via holes are designed along the sides of the main circuit.

Two pairs of quarter length resonators produce the two passbands separately with a pair of feed lines.

The measured results are nearly identical to the simulation results.

The final fabricated circuit view of the filter.