A 0.32-THz 6.6-dBm Single-Chain CW Transmitter Using On-Chip Antenna With 2.65% DC-to-THz Efficiency

A 0.324-THz multiplier-based (x16) transmitter with an on-chip patch antenna has been implemented in a 130-nm SiGe:C BiCMOS technology with an
$f_{\mathrm{T}}/f_{\mathrm{m}m}$
of 350/450 GHz. Power management and biasing are integrated on-chip for post-silicon optimizations of output power and de-to-THz efficiency. Each circuit block can be programmed over a serial peripheral interface for bias current. Three individually programmable low-dropout voltage regulators supply the x8 20-to-160-GHz multiplier chain, the two-stage 160-GHz power amplifier, and the 0.32-THz frequency doubler, respectively. Measurements after optimization reveal a dc-to-THz efficiency of 2.65% with an output power of 6.6 dBm and a dc power consumption of 170 mW operating at 0.324 THz.