In a companion paper, circuit design criteria were developed which lead to optimal performance in applying the six-port technique to the measurement of microwave parameters. A circuit which approximately satisfies these new design goals is described. Together with its several variants, it promises to become, in many applications, the "preferred" six-port circuit.
Glenn F. Engen, "An improved circuit for implementing the six-port technique of microwave measurements," IEEE Transactions on Microwave Theory and Techniques, vol. 25, no. 12, pp. 1080-1083, December 1977.
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