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A relatively wide field-of-view and high resolution imaging is necessary for navigating the scope within the
body, inspecting tissue, diagnosing disease, and guiding surgical interventions. As the large number of modes
available in the multimode fibers (MMF) provides higher resolution, MMFs could replace the millimeters-thick
bundles of fibers and lenses currently used in endoscopes.
However, attributes of body fluids and obscurants such as blood, impose perennial limitations on
resolution and reliability of optical imaging inside human body. To design and evaluate optimum imaging
techniques that operate under realistic body fluids conditions, a good understanding of the channel (medium)
behavior is necessary.
In most prior works, Monte-Carlo Ray Tracing (MCRT) algorithm has been used to analyze the channel behavior.
This task is quite numerically intensive. The focus of this paper is on investigating the possibility of simplifying this
task by a direct extraction of state transition matrices associated with standard Markov modeling from the MCRT
computer simulations programs. We show that by tracing a photon’s trajectory in the body fluids via a Markov chain
model, the angular distribution can be calculated by simple matrix multiplications. We also demonstrate that the
new approach produces result that are close to those obtained by MCRT and other known methods. Furthermore,
considering the fact that angular, spatial, and temporal distributions of energy are inter-related, mixing time of Monte-
Carlo Markov Chain (MCMC) for different types of liquid concentrations is calculated based on Eigen-analysis of the
state transition matrix and possibility of imaging in scattering media are investigated. To this end, we have started to
characterize the body fluids that reduce the resolution of imaging [1].
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