A 0.41-THz Coherent Harmonic Radiation Array Based on Mode-dependent Boundaries

This paper presents a simplified design method for coherent terahertz (THz) harmonic radiation array. The mode-dependent boundaries are applied to a half unit, which can be utilized to precisely simulate inter-coupling effects and avoid complex modeling for the entire array. Based on the proposed method, a 0.41-THz radiator with 16 coherent units is designed and characterized. Simulated and measured frequencies match closely, validating the feasibility of the proposed method. The radiator oscillates at 0.205 THz and radiates the second harmonic. The prototype chip is implemented in 130-nm SiGe BiCMOS process (f
T
/f
max
=300/450 GHz). It achieves an effective isotropically radiated power (EIRP) of 12.7 dBm, the directivity of 21.6 dBi while consuming 212 mW from 1.7 V supply.