A THz Pulse Radiator Based on PIN Diode Reverse Recovery

This paper presents a fully integrated oscillator-less THz pulse radiator based on reverse recovery of a PIN diode implemented using 130-nm SiGe BiCMOS technology. The chip radiates a wideband frequency comb in the THz regime through an on-chip antenna. The spacing between the THz tones can be programmed up to 10.5 GHz by tuning the frequency of the input trigger. The spectrum of the radiated frequency comb is measured from 320 GHz to 1.1 THz with 5.5-GHz spacing between the tones. The Non-Linear Q-Switching Impedance (NLQSI) technique is used for tuning the frequency tones and increasing the stability of the output stage. At a distance of 4 cm from the pulse radiator, the measured SNRs (including the losses) with 1 Hz resolution bandwidth are 51, 40, and 21 dB at 0.6, 0.8, and 1 THz, respectively with a 10-dB line-width of less than 2 Hz. With a 5.5-GHz input trigger, the total power consumption of the chip is 45 mW, with 20 mW consumed by the driver stage.