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An 8–18 GHz receiver implemented in silicon-germanium (SiGe) BiCMOS technology is presented. The receiver is designed to enable built-in test (BIT) and consists of a low noise amplifier (LNA), an image-reject mixer, on-chip, automatic gain control (AGC), ring oscillator (RO) sources (used to provide test signals of a predefined amplitude), and digital-to-analog converters (DACs), used for DC bias control of the blocks. The voltage and current biases of both the LNA and the mixer circuit blocks are used as tuning knobs for radio frequency (RF) performance metrics to mitigate the negative effects of total ionizing dose (TID) radiation damage present in extreme environments such as space. Samples of the receiver die were exposed to 10 keV X-rays at 1, 3, and 6 Mrad(SiO_2) doses. The BIT system was able to mitigate for TID damage in most cases, with improvements in the key RF metrics of gain, output third-order intercept point (OIP3), and noise figure (NF). The receiver was fabricated in an 0.18~\mu\m SiGe BiCMOS process technology with a peak f_T of 150 GHz and nominally consumes 241–243 mA from a 4~\V supply. [ABSTRACT FROM PUBLISHER]

We present a wideband, low noise amplifier (LNA) implemented in a Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT) technology. This SiGe LNA covers a frequency range of 8–16 GHz and achieves a peak gain of 17.5 dB at nominal bias and a peak OIP3 of 15.8 dBm at 10 GHz at nominal bias. The noise figure (NF) of the LNA is 4.5–8.1 dB across band, and it nominally consumes 4 mA from a 4 V supply. Samples were irradiated with 63.3 MeV protons to proton-equivalent doses ranging from 200 krad(Si) to 2 Mrad(Si). This LNA incorporates bias control “tuning-knobs” to enable bias tuning to mitigate for RF performance loss due to total dose exposure and process variation in performance metrics. The effectiveness of the tuning “knobs” to compensate for lost post-irradiated performance was investigated. It was found that the LNA performance can be restored with the use of the tuning knobs with a performance tuning algorithm. [ABSTRACT FROM AUTHOR]