Contribution of LTCC technology to the miniaturization of six-port networks

The six-port network has been identified in recent years as one of the best candidates to implement a Software Defined Radio (SDR). The main characteristic of the six-port architecture is its extremely large bandwidth, which involves multi-band and multi-mode capabilities. However, broadband six-port network designs lead to large size circuits. New technologies must be explored in order to achieve compact size and low-cost productions for configurable radio terminals. In this paper, the LTCC (Low Temperature Co-fired Ceramic) technology is proposed for implementing a six-port receiver. In the first place, we have developed an LTCC 90-degree hybrid coupler, which is the most critical component of the six-port network. Measurement results show a good performance over the frequency range from 1.5 to 6.5 GHz.