Intradyne coherent receivers, capable of detecting an individual wavelength-division multiplexed channel just by
tuning the local oscillator frequency, is of great interest for the development of high-capacity flexible optical
networks. Nevertheless, the unavoidable amplitude imbalances inherent to any realistic coherent receiver induce
an interference contribution from the self-beating of the coincident channels present at its input. The charac-
terization of this degraded colorless reception operation is of fundamental importance, but it usually requires the
use of rather complex experimental setups, especially when the effects of tens of interference channels should be
evaluated. In this work we propose a novel experimental setup that only requires the use of a single intense
interferer to emulate those coincident channels, thus drastically simplifying the characterization process. In
addition, we develop a general expression for the signal-to-noise ratio of the system that theoretically justifies the
intended setup and demonstrate by massive numerical simulations its accuracy in different scenarios. We believe
that the proposed approach may contribute to facilitate the experimental characterization of high-performance
colorless coherent receivers
