  Quantum Optical Coherence Tomography (Q-OCT) uses quantum properties of light
to provide several advantages over its classical counterpart, OCT: it achieves
a twice better axial resolution with the same spectral bandwidth and it is
immune to even orders of dispersion. Since these features are very sought-after
in OCT imaging, many hardware and software techniques have been created to
mimic the quantum behaviour of light and achieve these features using
traditional OCT systems. The most recent, purely algorithmic scheme - an
improved version of Intensity Correlation Spectral Domain OCT named ICA-SD-OCT
showed even-order dispersion cancellation and reduction of artefacts. The true
capabilities of this method were unfortunately severely undermined, both in
terms of its relation to Q-OCT and in terms of its main performance parameters.
In this work, we provide experimental demonstrations as well as numerical and
analytical arguments to show that ICA-SD-OCT is a true classical equivalent of
Q-OCT, more specifically its Fourier domain version, and therefore it enables a
true two-fold axial resolution improvement. We believe that clarification of
all the misconceptions about this very promising algorithm will highlight the
great value of this method for OCT and consequently lead to its practical
applications for resolution- and quality-enhanced OCT imaging.
