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Testing of rhythm identification algorithms used in automatic defibrillators is required by safety standards. The safety and efficiency of automatic defibrillators depends to a considerable extent on the adequacy of the testing procedure. It is recommended to use annotated public databases of ECG rhythms for testing of rhythm identification algorithms. An effective testing procedure includes two stages: computer simulation and real-time testing of the defibrillator.

Polygraphs--devices for simultaneous detection of several physiological parameters--are currently used in medicine in psychology. Special polygraphs are also used in scientific research. The process of data acquisition and processing in such polygraphs is usually computer-controlled. The goal of this work was to describe software for detection of polygraph signals used in cardiorespiratory system research. The software supports the experiment script language, allows hyperventilation testing, and makes it possible for the examination subject to control the data detection process.

A monitor of the biomechanical cardiac activity is described, which was elaborated on the basis of the accelerometer sensor and sigma-delta ADC for the purpose of registering the ballistocardiograms and seismocardiograms. The device ensures a non-stop signal recording for as long as 8 hours with the data being preserved in an inbuilt memory. Data are fed to the computer through the USB port. An algorithm is suggested for recordings processing by using the neuron-net technologies.

The paper contains a description of electroencephalography (EEG) photostimulator for examining the induced cerebral potentials. The device was designed to function within the EEG computer complexes; a high-intensity irradiation LED matrix is used as the light source. The 1.1 USB control bus serves as the communication interface; there is an extra external synchronization bus. It is possible to preset the frequency, brightness, on-off time ratio and pattern of light stimuli. A library of application programmer is supplied to monitor the photostimulation.

The use of a broad-band analogue-to-digital converter (ADC) with a reading rate of up to several kilohertz and with a subsequent digital filtration and decimation provides for obtaining the amplitude-and-frequency characteristics with the parameters, which are virtually unachievable for the ordinary analogue scheme technologies or digital filters inbuilt into the digital-filter integral ADC. Multi-digit ADC and digital signal processors (DSP) are used for the purpose. Additionally, with DSP it is possible to process algorithms of the broad-band ECG, like isolation of the impulse of the cardiac pacemaker.

The paper contains a description of the "Neurotest7A" signal generator designed for testing the electroencephalography and electrocardiography equipment, including its functional and technical characteristics, structural scheme and operational algorithm.

At present, personal computers (PC) are most available multimedia devices and used in the design of medical complexes. A problem occurs while choosing a device PC interface. The paper considers a USB interface and the use of its based computer medical complexes. A lot of advantages provided by the new interface, low cost and high efficiency make it possible to design up-to-date devices having high consumer qualities.

The paper describes the main features of the standard SCP-ECG that establishes a unified protocol for ECG data transmission both between the digital electrocardiograph and the computer control system and between the computer systems made by different manufactures. The paper also shows how to use via componential COM-technology a package of programme modules that support the input and output of electrocardiographic data in conformity with SCP-ECG.

The method of continuously measuring arterial blood saturation (pulse oximetry) has been recently intensively developed. The paper proposes a new schematic design of pulse oximeters based on the current multiple-digit sigma-delta transducers which reduces expenses connected with device operation, simplifies the regimen and algorithms of control, increases the quality of data reading.

With advances in the manufacture of super great integrated circuits, a commercially available element base that realizes the sigma-delta (sigma-delta) analog-to-digital conversion principle in one microcircuit has appeared. The sigma-delta analog-to-digital converters (ADC) have a high resolving power (above 12 bits), they are largely based on the signal digital filtration principles, which may moderate requirements for the analog filtration of signals and use direct-current amplifiers as alternatives to instrument ones. For electrocardiograph operation, the sigma-delta ADC of an AD 7716 (Analog Devices) with 22 bits were used in this study. The use of sigma-delta ADC in the electrocardiographs has been shown to be a rather useful alternative of traditional ADC. Moreover, sigma-delta ADC may be also useful for other systems for collecting and processing biomedical signals which are close in their requirements for a frequency range and a dynamic range, i.e. encephalographic, myographic, rheographic and other input signals.

The paper outlines one of the promising standards to transmit images in medicine, in radiology in particular. The essence of the standard DICOM is disclosed and promises of its introduction into computer-aided medical technologies.