Ruiz Molina, Juan CarlosNavarro Moreno, JesúsFernández Alcalá, Rosa MªJiménez López, José D.2025-01-192025-01-19202010.1016/J.JFRANKLIN.2020.02.012https://hdl.handle.net/10953/4155The paper deals with the estimation problem of a discrete-time vectorial quaternion signal which is observed through a linear dynamic system with intermittent observations and autocorrelated and cross-correlated noises. Under $\mathbb{C}^{\eta}$-properness conditions, a semi-widely linear processing is considered to provide filtering, fixed-point and fixed-lag smoothing algorithms for estimating the quaternion state. The proposed solutions give a substantial reduction in computational burden in relation to the widely linear estimation techniques, this benefit being impossible to be fully captured by using a real number framework. The feasibility and performance of the aforementioned algorithms are illustrated by means of simulation examples.engCC0 1.0 Universalhttp://creativecommons.org/publicdomain/zero/1.0/$\mathbb{C}^{\eta}$-propernessfilteringfixed-point and fixed-lag smoothing algorithmsintermittent observationsquaternion signalssemi-widely linear processinginfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccess