Compact Patch Antenna Array for 60 GHz Millimeter-Wave Broadband Applications

Abstract

In this study, a wide-band compact patch antenna array is developed for 60 GHz band applications. The antenna array consists of eight identical elements. Each element is a simple microstrip-fed rectangular radiating patch printed on the top side of a Rogers 5880 substrate. A rectangular ground plane is printed on the bottom side. To adjust the impedance matching for broadband operation, a complete circular-shaped slot and a part of circular-shaped slot are etched off the ground plane and the patch, respectively. A technique to feed the array elements unequally is employed for design a more compact antenna structure with improved gain and impedance bandwidth. An electromagnetic band-gap (EBG) reflector below the array structure is employed to decrease backward radiation and improve front-to-back (F/B) radiation ratio. The antenna array with the EBG reflector has a compact size with overall dimensions of 17.5 × 22 × 1.262 mm3. It achieves operation bandwidth from 56.5 to 65.2 GHz (|S11| ≤ − 10 dB), which covers the 60 GHz unlicensed band (57–64 GHz). The gain variation is from 12 to 16 dBi over the entire operating band. These features make the proposed antenna array system a suitable candidate for industrial, scientific and medical (ISM) broadband applications at 60 GHz band.