This letter proposes a dual band microstrip bandpass filter for dual band applications at 1 to 3 GHz for communication systems. the pass band of the filter covers 1.6 GHz in first band and 2.1 GHz in second band The design consists of four square loop resonators also known as loading elements present internally helps in designing compact filter. The advantage of the microstrip bandpass filters are that it is easy to integrate in the RF device, convenient to design, small in size and low insertion loss. This design is simulated using FR_4 substrate with dielectric constant of 4.6 and copper as the conductor.

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