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Modern wideband systems require low-noise receivers with bandwidth approaching 10 GHz. This paper presents ultra-wideband stable low-noise amplifier MMIC with cascode and source follower buffer configuration using GaAs technology. Source degeneration, gate and shunt peaking inductors are used to explore simultaneous wideband noise optimization and input power matching requirement. The low-noise amplifier circuit operates across a band of 0.3 to 10 GHz with a gain of around 14 dB and the measured noise figure NF below 1.5 dB up to 8 GHz. Measured small-signal results show good stability and very good agreement with simulated values. It is discussed in the paper that with more inductive peaking amplifier operation can be extended to even higher frequency, resulting in an even larger bandwidth.

In this paper, the high-frequency properties of MOSFETs at low-temperature operation are investigated through measurements and electrical simulations. The experimental results show that the device achieves a 335-GHz f(max) and a 300-GHz f(t) when operating at low temperature (78 K), which constitutes, respectively, a 78% and 34% improvement compared to the room temperature performances (296 K). The minimum noise figure NFmin decreases from 1.4 dB (296 K) to 0.5 dB at 30 GHz (78 K), while the associated gain increases from 8 to 12 dB.