A 440–540-GHz Transmitter in 130-nm SiGe BiCMOS

This letter presents a four-way combined frequency multiplier chain (FMC), which converts a single-ended 110-135-GHz input signal to a differential 440-540-GHz output signal. The four-way combined FMC uses four identical FMCs, which consist of two amplification and two frequency doubling stages. These blocks are designed with optimized parameters to be used as the transmitter of a gas spectroscopy system at 440-540 GHz. The four-way combined FMC has 0.5 dBm measured maximum output power at 450 GHz and -4.5 dBm at 500 GHz.