Design principles for multichannel fringing electric field sensors

Abstract
This paper presents general rules and principles for designing multichannel fringing electric field (FEF) sensors. A detailed analysis on how the design parameters, especially sensor geometry, affect the performance of FEF sensors is provided. Tradeoffs among different design objectives are explained, and qualitative design rules for balancing these tradeoffs are presented. The rules are illustrated with the design examples of two concentric FEF sensors. The effects of shielding electrode width and substrate thickness on sensor performance were evaluated through finite element simulations. In addition, the performance of the two sensors was compared based on the numerical calculations of penetration depth and signal strength. The comparison proves that the addition of shielding electrodes can improve the penetration depth of FEF sensors.