학술논문

Alternative fan-beam backprojection and adjoint operators.
Document Type
Article
Source
Journal of Inverse & Ill-Posed Problems. Dec2023, Vol. 31 Issue 6, p921-935. 15p.
Subject
*MATRIX multiplications
*RADON transforms
*COMPUTER simulation
*TOMOGRAPHY
*DETECTORS
Language
ISSN
0928-0219
Abstract
We present in this work alternative analytic formulations for the fan-beam tomographic backprojection operation and its associated adjoint transform in standard (equiangular) and linear (equidistant) detector geometries. The proposed formulations are obtained from a recent backprojection theorem in parallel tomography. Such formulations are written as a Bessel–Neumann series in the frequency domain that can be implemented as an O ⁢ (N 2.3729) matrix multiplication. Proofs are provided together with numerical simulations compared with conventional fan-beam O ⁢ (N 3) backprojection representations showing more robustness when dealing with highly noisy data. [ABSTRACT FROM AUTHOR]