A 325 GHz frequency multiplier chain in a SiGe HBT technology

A single-chip 325-GHz ×18 frequency multiplier chain based on two cascaded active differential triplers and a balanced output doubler is presented. The multiplier operates over a 317 to 328 GHz bandwidth with a 0-dBm 18-GHz input signal. A peak output power of -8 dBm is obtained at 325 GHz. The multiplier chain is realized in an evaluation SiGe HBT technology with cut-off frequencies f
_T
/f
_max
of 250 GHz / 380 GHz.