A Wide Band Coupler with High Directivity Using Phase Compensation for LTE

A small size bi-directional coupler with high directivity using phase compensation is presented in CMOS SOI 180nm process. To achieve a high directivity in the wide band, we introduce a phase compensation technique with simple RC circuits. The RC circuit can help to improve directivity and a coupling factor. The coupler integrated with SP8T is achieved with minimum 20 dB directivity and-23 dB coupling factor from 1.7 GHz to 2.7 GHz. The size of the fabricated coupler is only about 0.24 mm(2) including pads.