Novel application of two- and four-lobed noise-canceling passive integrated transponder antennas for tracking fish in areas of high ambient electromagnetic interference.

Passive integrated transponder (PIT) technology is a leading tool for tracking fish in freshwater systems. PIT is highly applicable for assessing fish passage at anthropogenic infrastructure (e.g., dams and floodgates); however, there are often complications in operating PIT antennas near these structures due to the ambient electromagnetic interference of metal and power-supply equipment. We designed a PIT antenna that is resistant to the effects of ambient electromagnetic interference (AEMI). This design uses lobes with balanced polarity within the antenna to neutralize AEMI within the vicinity of the antenna. This novel PIT antenna provides a more effective and cost-efficient option for researchers tracking fish in environments with high AEMI.