CONSTRUCTION OF A HIGH-PASS DIGITAL-FILTER FROM A LOW-PASS DIGITAL-FILTER

To remove low-frequency noise from data such as DC-bias from electromy ograms (EMGs) or drift from force transducers, a high-pass filter was constructed from a low-pass filter of known characteristics. A summary of the necessary steps required to transform the low-pass digital wer e developed. Contaminated EMG and force platform data were used to tes t the filter. The high-pass filter successfully removed the low-freque ncy noise from the EMG signals. The high-pass filter was then cascaded with the low-pass filter to produce a band-pass filter to enable simu ltaneous high- and low-frequency noise reduction.