Weakly electric fish use the electric field to detect objects in the neighborhood or communicate with conspecifics. They generate electric field with their electric organ and the electroreceptors sense the distortion of electric field caused by nearby objects. They use a modulated frequency signal of the Electric Organ Discharge (EOD), and it can be disturbed by similar frequency signals that neighboring weakly electric fish emit. They have a particular behavior response to change their EOD frequencies to avoid signal jamming. It is called jamming avoidance response. Inspired by the behavior of wave-type weakly electric fish, we propose an engineering perspective of jamming avoidance response model with the amplitude-phase modulation graph. The time course of the amplitude-phase graph of the EOD signal provides a cue to detect the jamming signal. We argue that the temporal integration can determine the shift direction of the EOD as well as the amount of the frequency shift to be moved frequency for the jamming avoidance response. Alternatively, as a fast adapting measure, the cross product of point vectors in the amplitude-phase graph allows early decision for jamming avoidance. We demonstrate the methods with simulations and the real experiments in the underwater environment.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2017R1A2B4011455).
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