SiP-based 60GHz 4×4 antenna array with 90nm CMOS OOK modulator in LTCC

A 60 GHz 4 × 4 circular polarized (CP) patch array antenna with a 90 nm CMOS OOK modulator are designed and integrated in low temperature cofired ceramic (LTCC) substrate to form a SiP-based transmitter. By applying a stripline sequential rotation feeding scheme, the CP array exhibits a wide impedance bandwidth (VSWR<;2) and 3 dB axial ratio (AR) bandwidth, both over 8 GHz. It has a beam-shaped pattern with a 3 dB beamwidth of 20° and a peak gain of 16.8 dBi. The CMOS modulator includes a 60 GHz oscillator and switchable amplifiers to provide the OOK modulation. By applying a bond wire compensation scheme and low-loss transition optimization, the CMOS modulator is successfully integrated into the package with 2mil 500 μm long bond wires. The final fabricated prototype measures only 22 × 13 × 1.4 mm³. The 60 GHz SiP transmitter is tested with a commercial receiver and a data rate of 2 Gbps is demonstrated. The energy usage at 2Gb/s is only 13.2 pJ/bit for the modulator.