%0 Electronic Article %A K. Schmalz %+ IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany %A Y. Mao %+ IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany %A J. Borngräber %+ IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany %A P. Neumaier %+ Deutsches Zentrum für Luft- und Raumfahrt (DLR), Rutherfordstr. 2, 12489 Berlin, Germany %A H.-W. Hübers %+ Deutsches Zentrum für Luft- und Raumfahrt (DLR), Rutherfordstr. 2, 12489 Berlin, Germany %K gas spectroscopy %K SiGe technology %K tunable transmitter %K active subharmonic mixer %K SiGe %K external dielectric lenses %K tunable receiver %K BiCMOS %K differential hybrid subharmonic mixer %K acetonitrile %K size 0.6 m %K differential low-noise amplifier %K constant frequency offset %K methanol %K gas absorption cell %K external phase-locked loops %K integrated local oscillators %K frequency 245 GHz to 122 GHz %X A 245 GHz sensor system for gas spectroscopy is presented, which includes an integrated SiGe transmitter (TX) and receiver (RX), and a 0.6 m-long gas absorption cell between the TX and RX modules. The integrated local oscillators (LOs) of TX and RX chips are controlled by two external phase-locked loops (PLLs), whose reference frequencies are swept with constant frequency offset for a low intermediate frequency of the RX. The RX consists of a differential low-noise amplifier, an integrated 122 GHz LO with a 1/64 divider, a 90° differential hybrid and an active subharmonic mixer. The TX consists of an integrated 122 GHz LO with a 1/64 divider, and a frequency doubler. The TX and RX chips are fabricated in 0.13 µm SiGe BiCMOS technology with f T/f max of 300 GHz/500 GHz. Using external dielectric lenses for the TX and RX modules, the gas absorption spectra were measured for acetonitrile and methanol. %@ 0013-5194 %T Tunable 245 GHz transmitter and receiver in SiGe technology for gas spectroscopy %B Electronics Letters %D June 2014 %V 50 %N 12 %P 881-882 %I Institution of Engineering and Technology %U https://digital-library.theiet.org/;jsessionid=1oa414iisknva.x-iet-live-01content/journals/10.1049/el.2014.0625 %G EN