Design and Analysis of fT-Doubler-Based RF Amplifiers in SiGe HBT Technology

Abstract

For performance-driven systems such as space-based applications, it is important to maximize the gain of radio-frequency amplifiers (RFAs) with a certain tolerance against radiation, temperature effects, and small form factor. In this work, we present a K-band, compact high-gain RFA using an fT-doubler topology in a silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) technology platform. The through-silicon vias (TSVs), typically used for small-size chip packaging purposes, have been effectively utilized as an adjustable matching element for input impedance, reducing the overall area of the chip. The proposed RFA, fabricated in a modest 0.35 µm SiGe technology, achieves a gain of 14.1 dB at 20 GHz center frequency, and a noise figure (NF) of 11.2 dB at the same frequency, with a power consumption of 3.3 mW. The proposed design methodology can be used for achieving high gain, avoiding a complex multi-stage amplifier design approach.

Simple Modeling and Analysis of Total Ionizing Dose Effects on Radio-Frequency Low-Noise Amplifiers

“…Lastly, C1, C2, and C3 were tuned for DC blocking (or AC coupling) and RBIAS supplied the desired current to the base terminal of Q4. For a theoretical analysis, a small-signal model of a SiGe HBT was constructed as shown in Figure 2 [24,25]. Whereas the complete small-signal-equivalent models were much more complex [26], only a few device parameters that were dominant in determining circuit performance were selected for simplicity.…”