Abstract-A 0.32-THz SiGe Imaging Array With Polarization Diversity

 Zhuang Li, Bukun Qi,  Xiaohui Zhang,  Saeed Zeinolabedinzadeh,  Lei Sang, John D. Cressler

https://ieeexplore.ieee.org/document/8263134/

A 0.32-THz 7 × 7 SiGe HBT incoherent detector array with both horizontal and vertical polarization capability is implemented in 0.13-μm SiGe BiCMOS technology. The average responsivity of the detector is 2.7 and 2.49 kV/W from 316 to 324 GHz for the horizontal and vertical polarizations, respectively, with a corresponding noise equivalent power of 23.8 and 25.8 pW/√Hz at an IF of 78.125 kHz. The contrast of metallic objects with features below the diffraction limit is enhanced by utilizing this chip's polarization diversities.

Abstract- Laser-Free THz pulse sources

M. Mahdi Assefzadeh,  Aydin Babakhani

http://ieeexplore.ieee.org/document/8067089/

Laser-free 0.03-1.1 THz signal generation and radiation in silicon is presented based on an oscillator-free direct digital-to-impulse architecture that is capable of generating and radiating pulses with a FWHM of 1.9 ps and a 3dB-BW of 130 GHz centered at 160 GHz. A peak pulse radiated power of 2.6 mW and a peak pulse EIRP of 19.2 dBm are achieved. To suppress ringing after the impulse and increase DC-to-radiated efficiency, an ON/OFF impulse-shaping technique is designed and implemented in the circuit level. Frequency-domain measurements are performed up to 1.1 THz, where the received SNR at 1.0 THz and 1.1 THz is 28 dB and 22 dB, respectively. An extremely narrow spectral line width is demonstrated with a 10-dB spectral width of only 2 Hz at 1.1 THz (two parts per trillion). Time-domain pulses are characterized using a novel fsec-laser-based THz-TDS measurement technique. The chip is fabricated in a 130-nm SiGe BiCMOS process technology.

Abstract- Gas Spectroscopy System for Breath Analysis at mm-wave/THz Using SiGe BiCMOS Circuits

 Klaus Schmalz,   Nick Rothbart ,  Philipp F.-X. Neumaier,  Johannes Borngräber,   Heinz-Wilhelm Hübers,  Dietmar Kissinger

http://ieeexplore.ieee.org/document/7836317/

The unique fingerprint spectra of volatile organic compounds for breath analysis and toxic industrial chemicals make an mm-wave (mmW)/THz gas sensor very specific and sensitive. This paper reviews and updates results of our recent work on sensor systems for gas spectroscopy based on integrated transmitter (TX) and receiver (RX), which are developed and fabricated in IHP's 0.13 μm SiGe BiCMOS technology. In this paper, we present an mmW/THz spectroscopic system including a folded gas absorption cell of 1.9 m length between the TX and RX modules. We discuss the results and specifications of our sensor system based on integrated TX and RX. We demonstrate TXs and RXs with integrated antennas for spectroscopy at 238-252 GHz and 494-500 GHz using integer-N phase-locked loops (PLLs). We present a compact system by using fractional-N PLLs allowing frequency ramps for the TX and RX, and for TX with superimposed frequency shift keying or reference frequency modulation. In another configuration, the voltage controlled oscillators of the TX and RX local oscillator are tuned directly without PLLs by applying external voltages. Further developments of our system are aimed at realizing an even wider frequency span by switching between frequency bands, and to use a more compact gas absorption cell.