On the use of seismic Rayleigh waves in security systems

There are four types of seismic waves: primary waves , secondary waves , wave Rayleigh and Love waves. The first two types are called depth waves, because these waves penetrate into the depths of the earth. Rayleigh waves and Love waves called surface waves. They can to propagate on the surface. Given the characteristics of propagation of these waves can be concluded that even at low energies excitation source, Rayleigh waves can propagate at a much greater distance than depth waves, so it would be advisable to use them in security systems. Knowing the velocity of the waves, which is measured the sensors, the ratio of amplitudes and time delays with which they come, we can determine the coordinates of the source of vibration. The output voltage of existing sensors (seismometers) is a function of frequency seismic waves and their amplitudes. This may be the cause of the error. Autor is suggested another principle of the sensor, output signal of which is a function only of the amplitude. Is posted conversion function of sensors and dependence on the sensitivity threshold. If we know threshold of the sensitivity of the sensors, with certain assumptions, we can estimated distance from which capacitive seismometer feels seismic waves excitedWalking man at different values of the coefficient of energy absorption of seismic waves geological environment. For seismic exploration seismic surface waves are interference. Most likely, thismay explain the lack of information about the amount of energy that falls on the formation of surface waves and the dependence of this quantity on the power source. Zone of sensitivity may be limited to so-called microseisms arising from soil vibrations caused by fluctuations of the trees, transport, and industry. To limit the impact of microseisms be appropriate to apply filters. Therefore, before decision about the possibility of practical implementation of such systems, data relating to the area of sensitivity of seismometers need additional experimental verification in the field where necessary to experimentally explore: how much energy of the source belongs Rayleigh waves and Love waves ; energy distribution between surface waves; by the ratio of amplitudes determine the absorption coefficient of surface waves for areas where the security system will be used.