A miniature lumped element LTCC quadrature hybrid coupler for GPS applications

A new high performance hybrid coupler has been presented that has an extreme degree of miniaturization. The device is based on a lumped equivalent model of a conventional hybrid coupler and was realized in a standard low permittivity LTCC technology. Measured results show insertion losses within 0.65 dB of the theoretical maximum, an amplitude imbalance of less than 0.18 dB and a phase difference of 87.4 degrees. The good performance and small size of the device presented here make it suitable for use as a discrete component for various purposes or as an integrated component for system-in-package applications. Also, the methodology used here is useful for the design of couplers for frequencies up to C-band range.