A dual-band BPF for concurrent dual-band wireless transceiver

The development of concurrent dual-band wireless transceiver has enhanced the miniaturization of all blocks used in the wireless transceiver. That is achieved by casting the two single-band blocks into a dual-band block. In this paper, a dual-band BPF for the concurrent dual-band wireless transceiver is developed. A stepped impedance resonator (SIR) is used to implement the dual-band BPF because of its controllable spurious response property. The filter is implemented on the LTCC substrate, where the second pass-band is obtained by making use of the spurious response. Here, a 590×590 mils² dual-band BPF that has center frequencies of 2.4GHz and 5.2GHz, less than 2dB insertion loss, greater than 20dB return loss, and more than 5% bandwidth is successfully developed.