AWideband Frequency Beam-Scanning Antenna Array for Millimeter-Wave Industrial Wireless Sensing Applications

The 57–71-GHz millimeter-wave (mmWave) industrial, scientific, and medical (ISM) band holds significant potential for enhancing the performance of next-generation industrial wireless applications. This article first presents the design and analysis of a compact and high-performance eight-element series-fed frequency beam-scanning array designed to cover the entire 21.87% fractional bandwidth (FBW) of the 57–71-GHz ISM band. Using this as a subarray, a hybrid parallel–series feed topology is designed to construct a 64-element (
$8\times8$
) planar array with high-gain directional beams. The planar array provides a peak measured gain of 20.12 dBi at 64 GHz and maintains a flat gain of over 19.23 dBi throughout the band, with a 1-dB gain bandwidth of 13 GHz. Its narrow directional beams provide an average half-power beamwidth (HPBW) of 9.7° and 11.78° in the elevation and azimuth planes, respectively, facilitating point-to-point mmWave connectivity and high-resolution beam scanning. The inherent phase variation of the series-fed topology is employed to produce a beam-scanning range of 40° within the 57–71-GHz band, with a scan loss of less than 1 dB. The proposed array is a low-cost and reproducible solution for seamless integration with V-band mmWave equipment, as elucidated through practical demonstration frameworks using the mmWave power sensor and EK1HMC6350 evaluation board. The proposed array is well-suited for emerging industrial wireless sensing and imaging applications, and mmWave frequency scanning radars. Its versatility extends to various 60-GHz protocols, such as IEEE 802.11ay, IEEE 802.11ad, IEEE 802.15.3c/d, and WirelessHD, and other customized industrial protocols such as WirelessHP.