[4] P H Siegel. THz for space: The golden age, 816-819(2010).
[5] M Tonouchi. Cutting-edge terahertz technology. Nature Photon, 1, 97-105(2007).
[17] N R Erickson, B J Rizzi, T W Crowe. A high power doubler for 174 GHz using a planar diode array, 287-296(1993).
[21] A Maestrini, C Tripon-Canseliet, I Mehdi. Design of a wideband 6-anode frequency tripler at 300 GHz with optimum balance, 203.
[30] J V Siles. Design of a high-power 1.6 THz Schottky tripler Using 'On-chip' Power-Combining and Silicon Micromachining, 26-28(2011).