In signal processing, a lifter is a signal transform consisting of taking the decibel transform of a signal, convoluting it with some function, and taking the inverse Fourier transform of the result after undecibelizing. The effect is to enhance or attenuate the gamnitude of certain quefrencies.
In electrical and mechanical engineering, a Lifter is a field-effect propulsion device powered by high-voltage in the range of several 10 kilovolts. The underlying principle is called the Biefeld-Brown effect.
Lifters exhibit Vertical take-off and landing characteristics when powered. They are composed of aluminum or other lightweight conductive materials and usually do not have any moving parts.
A lifter is basically an asymmetric capacitor, asymmetric meaning that the size of the two electrodes is significantly different. The diameter of the electrodes are usually about 0.1mm and 2cm, respectively.
Small Lifter models powered by high-voltage flyback transformers have been made and succesfully tested by several companies and hobbyists. These Lifters usually have a triangular shape or are built of many triangular submodules. The usual side length is between 15cm and 1m. The smaller electrode usually consists of a thin copper wire and the larger electrode is built using aluminium foil. The supporting frame is made of a light material such as balsa wood, straw blades, or styrofoam. This frame ensures a constant distance of a few centimetres between the two electrodes.
