Abstract: A method and an apparatus for compressing and displaying digital data, in particular beat-to-beat heart rate data in fetal monitoring, operates according to the principle of the "maximum absolute differences", i.e., the data discovered in a certain interval are compared with a start value, and the data with the highest absolute difference in relation to said start value is chosen as representative for the data discovered in such interval. This results in an effective data compression, without suppressing higher-frequency signal components--which are very important for certain applications--significantly.

Abstract: An apparatus for evaluating the fetal condition prior to or under birth receives the signals of a fetal heart rate transducer and a toco transducer. The signals are first preprocessed in the time domain and in the frequency domain. A trace processor identifies possible events like decelerations and contractions. These are validated by a validation processor, whose output is then classified by a classification processor. A score processor scores the events and cooperates with an alarm handler and a reasoning processor. The rules according to which these processors operate are stored in a rule memory and may be edited or selected, or new rules may be set up, by a display or personal computer under control of an expert interface.

Abstract: A sensor for non-invasive measurement of oxygen saturation using the reflection method comprises a red transmitter (55), an infrared transmitter (58) and a receiver (57). The distances between the transmitters and the receiver are selected such that the length of the light path (60, 61) between the red transmitter (55) and the receiver (57) is substantially equal to the length of the light path (62, 63) between the infrared transmitter (58) and the receiver (57). The sensor comprises a further red transmitter (56) which is used for another application at the human body or another tissue characteristics where the depth of penetration at the various wavelengths is different from the shown example. Together with an appropriate oximeter, manual or automatic adaptation is possible. Further signal improvement may be obtained by autocorrelating the received signal, detecting its frequency and cross-correlating it with a pattern function of the same frequency.

Abstract: A sensor for non-invasive measurement of oxygen saturation using the reflection method comprises a red transmitter (55), an infrared transmitter (58) and a receiver (57). The distances between the transmitters and the receiver are selected such that the length of the light path (60, 61) between the red transmitter (55) and the receiver (57) is substantially equal to the length of the light path (62, 63) between the infrared transmitter (58) and the receiver (57). The sensor comprises a further red transmitter (56) which is used for another application at the human body or another tissue characteristics where the depth of penetration at the various wavelengths is different from the shown example. Together with an appropriate oximeter, manual or automatic adaptation is possible. Further signal improvement may be obtained by autocorrelating the received signal, detecting its frequency and cross-correlating it with a pattern function of the same frequency.