EXTENDING THE CAPABILITY OF SEISMIC SENSORS USING A UNIVERSAL FILTER TRANSFER FUNCTION

Abstract

In recent years the global trend in seismological observations consists in increasing the number of measuring points and equipping them with broadband and highly sensitive sensors. However, this approach leads to a significant rise in the cost of measurements. One possible solution to this problem is the use of much cheaper geophones or short-period seismometers with an extended frequency range as additional sensors. This paper discusses the process of synthesizing a correction filter circuit based on a biquadratic transfer function, and provides schemes for expanding the frequency characteristics of sensors, including circuits for correcting the characteristics of the SM-3KV seismometer and the GS-20DX geophone in instrument design. The developed algorithm makes it possible to expand the frequency response of the SM-3KV seismometer to low frequencies region up to 0.02 Hz (natural frequency of 0.5 Hz) and the GS-20DX geophone to 1 Hz (natural frequency of 10 Hz).