Abstract
The present article will explain in some details the requirements of modulators and demodulators using quadrature splitters and combiners, and discuss the target specifications for these devices. The architecture of a passive RC network, useable as a quadrature splitter/combiner is then introduced, the design choices are described, the results of simulations and tests are given. Then, we present a full characterization of some of our modulators and demodulators along with a tuning strategy which achieves an outstandingly accurate quadrature signal processing, and characterizes the error terms of the device at the same time.
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