In this work, we propose an integrated long-range (LoRa; 0.92‒0.925 GHz) and global navigation satellite system (GNSS; 1.164‒1.189 GHz, 1.559‒1.609 GHz) antenna in a compact package, addressing the challenge of integrating antennas into highly size-limited applications. High radiation efficiency was achieved for the LoRa antenna by constructing a both-side-open-ended bent half-wavelength slot line, effectively preventing the cancelation of electric fields. Similarly, a compact configuration for the dual-band GNSS antenna was achieved using one-side-open-ended and quarter-wavelength slot lines. Finally, the LoRa and GNSS antennas were successfully integrated into a small printed circuit board. Furthermore, we introduce a method to measure the antenna while it is electrically connected to a control board and a battery while also evaluating its effects on operating frequencies. The simulated and experimental results demonstrated impedance bandwidths that cover the LoRa and GNSS bands, as well as the radiation efficiencies (64.9%, 46.3%, 54.2%) and radiation patterns of the proposed antenna. Overall, the proposed antenna exhibited compactness and radiation efficiency that surpassed other LoRa and GNSS antennas, even in the presence of unfavorable packaging effects.
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