Non-invasive UWB sensing of astronauts' breathing activity.

The use of a UWB system for sensing breathing activity of astronauts must account for many critical issues specific to the space environment. The aim of this paper is twofold. The first concerns the definition of design constraints about the pulse amplitude and waveform to transmit, as well as the immunity requirements of the receiver.

Reduction of Walsh-transformed electrocardiograms by double logarithmic coding.

This work presents an electrocardiogram ECG data reduction method based on Walsh spectrum double logarithmic quantization. The technique is theoretically justified for a simulated ECG and its practical efficiency confirmed using MIT/BIH arrhythmia database signals. By classifying a "good" compression as one with MSE < or = 0.