Biologically Inspired Electrically Small Antenna Arrays With Enhanced Directional Sensitivity

Many insects possess acute directional hearing capabilities and are able to localize sound sources of interest with an astonishing degree of precision. An analogy can be drawn between the auditory systems of such insects and electrically small antenna arrays that demonstrate enhanced sensitivity to the direction of arrival of an electromagnetic wave, compared to regular arrays occupying the same aperture. Inspired by this, we discuss the design of biologically inspired electrically small antenna arrays that mimic the hearing mechanism of such insects. A method for designing such antenna arrays is presented, and the tradeoffs involved in achieving this enhanced sensitivity are discussed. Simulation and measurement results of two fabricated prototypes are also presented and discussed in this letter.