How should I downsample my sensor?

1. How do you downsample a signal?
2. Why do we downsample a signal?
3. What is downsampling of EEG data?
4. Does downsampling cause aliasing?

How do you downsample a signal?

y = downsample( x , n ) decreases the sample rate of x by keeping the first sample and then every n th sample after the first. If x is a matrix, the function treats each column as a separate sequence. y = downsample( x , n , phase ) specifies the number of samples by which to offset the downsampled sequence.

Why do we downsample a signal?

(1) To make a digital audio signal smaller by lowering its sampling rate or sample size (bits per sample). Downsampling is done to decrease the bit rate when transmitting over a limited bandwidth or to convert to a more limited audio format.

What is downsampling of EEG data?

Downsampling according to research goals

EEGLAB offers the possibility to downsample EEG datasets. In general, the selection of a sampling rate should be driven by research goals. If the goal of your research is to characterize ERP components, then a sampling rate of 250 Hz could be more than adequate.

Does downsampling cause aliasing?

If a discrete-time signal's baseband spectral support is not limited to an interval of width 2 π / M radians, downsampling by M results in aliasing. Aliasing is the distortion that occurs when overlapping copies of the signal's spectrum are added together.