title: Frequency- and Phase Encoded SSVEP Using Spatiotemporal Beamforming.
abstract: In brain-computer interfaces (BCIs) based on steady-state visual evoked potentials (SSVEPs) the number of selectable targets is rather limited when each target has its own stimulation frequency. One way to remedy this is by combining frequency- with phase encoding. We introduce a new multivariate spatiotemporal filter, based on Linearly Constrained Minimum Variance (LCMV) beamforming, for discriminating between frequency-phase encoded targets more accurately, even when using short signal lengths than with (extended) Canonical Correlation Analysis (CCA), which is traditionally posited for this stimulation paradigm.
authors.affiliation: Laboratory for Neuro- and Psychophysiology, K.U. Leuven, Leuven, Belgium.
authors.forename: Benjamin
authors.identifier: http://orcid.org/0000-0002-4662-5749
authors.initials: B
authors.lastname: Wittevrongel
authors.affiliation: Laboratory for Neuro- and Psychophysiology, K.U. Leuven, Leuven, Belgium.
authors.forename: Marc M
authors.initials: MM
authors.lastname: Van Hulle
mesh_terms: D000328:Adult; D062207:Brain-Computer Interfaces; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D012815:Signal Processing, Computer-Assisted; D055815:Young Adult