A 260–300-GHz Mixer-First IQ Receiver With Fundamental LO Driver in 130-nm SiGe Process

We report a 280-GHz mixer-first quadrature receiver in 130-nm SiGe that achieves a peak gain of 25 dB, an IF bandwidth of 30-GHz, and a minimum single-sideband (SSB) noise figure (NF) of 18.2 dB. The receiver is comprised of two Gilbert-cell mixers with swapped RF and local oscillation (LO) ports that downconvert the RF signal at 260–299 GHz to I/Q IF signals at 1–40 GHz by using a pseudo-differential LO driver at 259 GHz. In each channel, a wideband IF amplifier was used for an aimed conversion gain of higher than 20 dB. Combined with a differentia hybrid coupler, an integrated 259-GHz driving amplifier (DA) was integrated to generate the quadrature LO signals for I and Q channels. The measured amplitude and phase imbalance between the I and Q channels are around 4 dB and 4°, respectively. The fabricated chip occupies a whole area of 1.12 mm2 and consumes a dc power of 384 mW.