Pivoting underwater RFID antenna assembly

摘要

An underwater antenna assembly (or array thereof) suitable for subsurface RFID tag interrogation in flowing water such as a river. In preferred embodiments, the antenna interrogates RFID tags implanted in aquatic species. The antenna resides in an elongate antenna housing whose cross-sectional shape is preferably a hydrodynamic teardrop shape. A first end of the housing is linked to a pivoting mechanism such that when the pivoting mechanism is held substantially stationary with respect to the water flow, the second end of the housing is free to rotate generally about the first end in a substantially vertical plane parallel to the water flow direction. The length of the antenna housing is advantageously selected to enable the antenna to monitor for signals across substantially the entire water depth.

主权项

1. An underwater antenna assembly for subsurface RFID interrogation in flowing water, the water having flow in a known water flow direction, the water flowing over a bottom bed, the water further having a nominal water depth above the bottom bed, the antenna assembly comprising:
an antenna, the antenna suitable for RFID interrogation; an elongate antenna housing, the antenna housing including a housing length separating first and second ends thereof, the antenna resident in the housing, the housing length having a predetermined hydrodynamic cross-sectional shape perpendicular to the housing length; and a pivoting mechanism linked to the antenna housing at the first end thereof such that when the pivoting mechanism is held substantially stationary with respect to the water flow, the second end of the antenna housing is free to rotate, responsive to water flow, about the first end in a substantially vertical plane parallel to the water flow direction.