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In this paper, a compact dual‐band bandpass filter (DB‐BPF) is implemented by using a pair of coupled stepped impedance resonators (SIRs) and a pair of λ/2 bended resonators for the modern wireless communication systems such as WiMAX and WLAN (3.4 and 5.4‐GHz). The physical layout is presented and explained the establishment of an LC equivalent circuit. Moreover, the second passband of the proposed dual‐band bandpass filter can be independently controlled by inserting the open‐circuited stubs at the end of the λ/2 bended resonators without increasing the circuit size. Simulation results show that the second passband can be ranged from 5.6 to 4.8‐GHz with the bandwidth of 400 ± 96‐MHz, whereas the first passband is fixed with the bandwidth of 280 ± 8.5‐MHz. The measured results exhibit the insertion losses (S21) lower than 1.2 and 1.4 dB, and the return losses (S11) of −23 and −32 dB at the first and second passbands, respectively, which show a good agreement with simulation results. The dual‐band microstrip filter is fabricated on RT/Rogers 4003 substrate with a compact size of 0.24λg × 0.25λg.

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