Robust Frequency-Calibrated Virtual EEG Channel Generation from Four Frontal Electrodes for Wearable EEG Augmentation
For wearable EEG applications, this provides a method to augment sparse frontal recordings with frequency-calibrated virtual channels, though gains are incremental over existing interpolation baselines.
FAVC-Net generates 13 virtual EEG channels from four frontal electrodes, achieving 30.09% and 37.98% reductions in log-spectral distance and PSD KL divergence over the best baseline, while maintaining robustness to source perturbations.
Low-channel wearable electroencephalography (EEG) is attractive for long-term monitoring, but four frontal electrodes provide only a sparse and spatially biased view of distributed scalp activity. We present FAVC-Net, a compact frequency-calibrated virtual-channel network that generates 13 unmeasured EEG channels from Fp1, Fp2, F7, and F8. The model combines shared multi-scale source encoding, source-state embeddings, target-conditioned signed source-block mixing, GATv2-based attention refinement, attention-consistent skip fusion, and weak Welch power spectral density calibration. Rather than treating sparse-to-dense EEG generation as a purely waveform-matching task, the framework jointly emphasizes amplitude fidelity, spectral allocation, channel-frequency texture, and robustness to corrupted wearable inputs. On the PRED+CT dataset, FAVC-Net achieved the best joint waveform-spectral operating point among neural and interpolation baselines. Its time-domain gains were modest, whereas log-spectral distance and PSD KL divergence were reduced by 30.09% and 37.98% relative to the strongest non-FAVC comparator. Under wearable-like source perturbations, the model preserved spectral fidelity and resisted spectral collapse. These results support virtual EEG channel generation as a dual-domain augmentation problem, while emphasizing that generated posterior and parietal channels should be interpreted as frequency-calibrated representations derived from sparse frontal measurements rather than as independent physical recordings.