CRAMER-RAO LOWER BOUND ANALYSIS FOR MAGNETIC LOCALIZATION OF A ROBOTIC CAPSULE ENDOSCOPE

Abstract

In robotic capsule endoscopy, highly accurate localization of the capsule device inside the human body is a critical problem for disease diagnosis and treatment. Quantitative analysis of lower bounds, such as the Cramer-Rao Lower Bound, is practically important for localization systems, as they inform system designers of the best achievable performance under a given set of conditions. This paper presents a comprehensive, systematic analysis of the Cramer-Rao Lower Bound for the scenario of magnetic localization of a robotic wireless capsule endoscope inside the human body. The specific contributions of the study are threefold. First, we undertake a systematic analysis of the bound in the presence of a realistic 3D body model. Second, we present a detailed analysis of the effects of capsule motion as well as other system parameters (such as magnet type and magnet dimensions) inside the body on the bound values. Finally, we interpret the findings to come up with recommendations on system parameters to guarantee optimal performance.

Keywords

• Cramer-Rao Lower Bound
• Magnetic Localization
• Robotic Capsule Endoscopy

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