A 160-GHz Subharmonic Transmitter and Receiver Chipset in an SiGe HBT Technology

A monolithically integrated 160-GHz transmitter and receiver chipset with in-phase/quadrature baseband inputs and outputs and on-chip local oscillator (LO) generation has been implemented in a 0.25- μm silicon-germanium heterojunction bipolar transistor technology. The chipset features a three-stage differential power amplifier, a low-noise amplifier, up- and down-conversion subharmonic quadrature mixers, and an 80-GHz voltage-controlled oscillator equipped with a 1/16 frequency prescaler for frequency locking by an external phase-locked loop. To investigate the behavior of the Gilbert-cell-based subharmonic mixer operated close to
f
_max
, the correlation between LO phases and conversion gain is studied. The conclusion suggests that the maximum conversion gain can be obtained with certain LO phases at millimeter-wave frequencies. Over the 150-168-GHz bandwidth, the transmitter delivers an output power of more than 8 dBm with a maximum 10.6-dBm output power at 156 GHz. The receiver provides a noise figure lower than 9 dB and more than 25 dB of conversion gain at 150-162 GHz, including the losses of an auxiliary input balun. The transmitter and receiver chips consume 610 and 490 mW, respectively.