A Compact 1.71-2.69GHz Diplexer Based on HRS IPD Technology

In this paper, a compact 1.71-2.69GHz diplexer is designed and fabricated for mobile phone terminals based on high-resistivity silicon (HRS) integrated passive device (IPD) technology. Low insertion loss and compact size can be achieved by utilizing new LC resonances to provide transmission zeros. The chip size of the diplexer is 1.525mm×0.95mm×0.1mm. Test results show that the operating center frequencies of the low and high frequency bands of the diplexer are 1.94 GHz and 2.595 GHz, respectively. The low band maximum insertion loss is 1.3dB in 1.71GHz ~ 2.17GHz. The high band maximum insertion loss is 0.7dB in 2.5GHz ~ 2.69GHz. The isolation between two bands is better than 11.2dB in 1.71GHz ~ 2.69GHz.