Ku- to W-band silicon germanium RFIC and RF MEMS sub-systems

Automotive radar systems at 77 GHz are built using expensive III-V semiconductor such as GaAs or InP, and this makes the price of the adaptive cruise control (ACC) system too high for most cars. The emerging SiGe and RF MEMS technologies are used in this thesis to implement low cost and high performance mm-wave components, thereby opening the venue for use in virtually all automotive platforms.; State-of-the-art W-band 3-bit phase shifters using distributed MEMS transmission lines on glass substrates were developed. A figure of merit of 93--100°/dB was achieved at 75--110 GHz and the measured results fit very well with the full-wave simulations for a single-cell combined with ADS network analysis for the entire phase shifter. Careful loss analysis indicates that the performance can be improved to 150--200°/dB if integrated on quartz substrates.; High-efficiency monolithic Ku- and Ka-band balanced frequency doublers were built using commercial SiGe bipolar process (Atmel Corporation, SiGe2-RF). The Ku-band design presents an output power of 5--6 dBm from 15.4--18 GHz and the corresponding power added efficiency (PAE) is 9.2%. The Ka-band design demonstrates an output power of 10.5 dBm at 36 GHz with a PAE of 6.4% and a high spectral purity with a fundamental suppression of 35 dB. To our knowledge, these are the best results for active doublers using any technology.; A novel SiGe 77 GHz subharmonic balanced mixer is presented with a goal to push the technology to its limit (SiGe2-RF transistor f T = 80 GHz). This new topology uses a compact input network to not only achieve the isolation between LO and RF ports, but also to result in excellent 2LO-RF isolation. The measured results demonstrate the conversion gain of 0.7 dB at 77 GHz with an LO power of 10 dBm at 38 GHz, LO-RF isolation better than 30 dB, 2LO-RF isolation of 25 dB, and a P1db of -8 dBm. The circuit demonstrates that SiGe subharmonic mixers have comparable performance with GaAs designs, at a fraction of the cost.