Optimal digitization of body surface potential maps

Since the measuring systems are very complex, attempts have been made to simplify them by reducing the number of employed electrodes. The simplification can also be achieved by using a special kind of front end, where the electrodes need only to detect the times when the potentials on the thorax cross some given threshold level. The optimal tradeoff is studied between reducing the number of electrodes and the coarse quantization of the amplitude range. The reconstruction algorithm is based on estimation of decomposition coefficients from multiple level-crossing times and then constructing the original map by linear combination of eigenfunctions (calculated for a training set of complete map measurements), according to these coefficients. The tradeoff should tend towards a denser sampling grid comprising electrodes with coarse quantization range