Gain and Stability Models for HBT Grid Amplifiers - Antennas and Propagation Society International Symposium, 1995. AP-S. Digest
نویسندگان
چکیده
A 16-element heterojunction-bipolar-transistor (HBT) grid amplifier has been fabricated with a peak gain of 11 dB at 9.9 GHz with a 3-dB bandwidth of 350 MHz. Here we report a model of gain analysis for the grid and give a comparison of the measurement and theory. Measured patterns gives evidence of a common-mode oscillation. A stability model for the common-mode oscillation is developed. Based on the stability model, a lumped capacitor gives suitable phase shift of the circular function, thus stabilizing the grid. A second 16-element grid was fabricated, using this theory, with improved stability.
منابع مشابه
A 100-Element MODFET Grid Amplifier - Antennas and Propagation Society International Symposium, 1995. AP-S. Digest
A 100-element quasi-optical amplifier is presented. The active devices are custom-fabricated modulation-doped field-effect transistors (MODFET’s). Common-mode oscillations were suppressed using resistors in the input gate leads. The grid has 9 dB of gain at 10.1 GHz. The 3-dB bandwidth is 1.2 GHz. We present a model for the gain of the grid versus frequency and compare measurement with theory.
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