Centre-fed series array antenna for K-/Ka-band electromagnetic sensors

摘要

This study introduces a novel series array antenna for passive millimeter wave sensor applications, particularly physical securities and vigilance sensors. The antenna is mainly composed of a three-line series array and has a symmetrical structure whereby a 'Chebyshev polynomial' has been used to obtain a low side-lobe characteristic. For a more symmetrical antenna pattern, the authors considered a centre feeding structure from an input port to the three individual linear arrays. This feeding structure is very helpful when it comes to designing centre-fed and non-edge-fed multi-line linear arrays with low dividing losses. For the verification of the array design, the authors implemented the feeding structure to a K-band electromagnetic (EM) sensor antenna. This array was fabricated on a printed circuit board, and showed good performance to satisfy the required specification for an EM sensor. The authors designed another Ka-band array with the same structure as the K-band model, and found that the gain of the array can be increased by controlling the inclined angle of the side wings. Using the side wings, the authors were able to realise high gain performances in conformal size without variation in other types of performance.