Apart from airflow signal what other signals (EEG, EMG, ECG,SpO2, etc) can be obtained from the PSG dataset? Also, How much noise is present in the dataset? Can I download part of a dataset instead of downloading the whole?
Signals such as the ones you list are available in the datasets. Available signals vary per dataset. Individual studies can be downloaded.
Most datasets contain a "Montage and Sampling Rate Information" page, which describes the signals most commonly found in the PSG/EDF data.
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