Seismic Noise Rejection System for a Rise-and-Fall Absolute Gravimeter

The gravimetric prospections are usually performed by using relative instrumentations, having suitable features to work outside a lab or on a vehicle/ship. Nevertheless their relative measures have to be referred to an absolute measure which represents the reference point. These last measurements are not easy to perform due to the difficulty to operate in open field with an absolute-gravimeter. The measurements should be done by using a field-portable instrument able to maintain the high level of precision required to an absolute-gravimeter. In this work we describe the state of the art in the improvements to the portable Absolute-Gravimeters (AGs), focusing on the possibility to measure and remove the seismic noise which acts on its reference frame. These measurements are done with a special accelerometer embedded in the AG. To process and record data from the AG and from the accelerometer, will be used a Field Programmable Gate Array (FPGA) which, permits an high level of integration of the system and to customize the electronic systems with just minor hardware designs.