IEEE Transactions on Applied Superconductivity

Study of a Multi-Channel RF Amplifier Based on DC SQUID for 3–5 GHz Band

G.V. Prokopenko, S. V. Shitov, I.L. Lapitskaya, Satoshi Kohjiro, Masaaki Maezawa, Alexandre Shoji

Published Jun 1, 2005• 4 citations

Abstract

A low-noise rf amplifier based on a dc SQUID (SQA) is developed and tested within frequency range 3.0-4.5 GHz. The 4-channel chips are designed using proven balanced output configuration; they employ special damping filters. Each channel is tested separately demonstrating the following parameters at 3.95 GHz central frequency: gain (9.5 /spl plusmn/ 1.0) dB, 3-dB bandwidth 300 MHz and noise temperature (1.0 /spl plusmn/ 0.5) K. The 1-dB gain compression estimate is 50 K*GHz for bias voltage 80 /spl mu/V and characteristic voltage 285 /spl mu/V.

DOI: 10.1109/tasc.2005.850033

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