Low-Cost Wideband Millimeter-Wave Filtenna and Its Arrays for Miniaturized IoT Devices
Yuechao Wang, Jun Xu, Lei Xiang, Kai Chen, Wei Hong
Abstract
A low-cost millimeter-wave wideband filtenna integrating filtering and radiation performance for next-generation millimeter-wave (mmWave) Internet of Things (IoT) devices is proposed in this article. The filtering performance is achieved by utilizing the intrinsic high-pass property of a microstrip-fed magneto-electric dipole (ME-dipole) and filtering feeding mechanism. Several shorted parasitic patches are settled around the E-dipole to enhance the radiation performance within the operating band and develop suppression levels at both the lower and upper bands. A stepped cross-shaped microstrip-line structure is added in the center of the radiating aperture to generate two resonances, so that the in-band impedance performance and the selectivity can be improved. Measurement results indicate that the proposed filtenna achieves a wide operating bandwidth of 30.26% (22.8-31.4 GHz), a peak gain of 8.21 dBi and an out-of-band gain suppression better than 23 dB. Furthermore, a 2×2 filtenna subarray is constructed with some shorted parasitic patches being shared, and then, a 4×4 circularly-polarized (CP) sequential rotated (SR) array is also delicately designed using the 2×2 filtenna subarray. Remarkable operating bandwidths and appropriate out-of-band suppression performance with simplistic structures are all confirmed well through experiments. The outstanding performance of the proposed filtenna and its arrays makes them potential candidates for the B5G/6G mmWave communications.