Highly integrated triplexers for WiMAX applications

This paper presents compact and highly integrated triplexers for WiMAX applications using multilayer low temperature co-fired ceramic (LTCC) technology. Two different triplexers composed of three embedded bandpass filters and matching networks are designed and implemented. The measured result of the first triplexer shows that the insertion losses are less than 2.4 dB and 2.0 dB in 2-GHz and 3-GHz bands, respectively. The insertion loss in 5-GHz path is better 1.1 dB. The return losses at antenna port are better than 13 dB for all three bands. The second triplexer, which has the same bandpass filters but less matching components compared with the first one, provides similar frequency response. The measured results of the filters and triplexers are in good agreement with the simulated ones. The size of both triplexers is only 5.0 mm times 4.0 mm times 0.5 mm.