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A compact wideband circularly‐polarized (CP) RF identification (RFID) handheld reader antenna based on inverted‐F antennas (IFAs) is proposed. The antenna consists of an upper layer of rotationally symmetric radiation structure and lower layer of feed network. Firstly, the feed network is verified by microwave circuit simulation software. Then the antenna is modeled and simulated with the aid of the full‐wave electromagnetic simulation software. Finally, a prototype is fabricated using FR4 plate and its performance of the proposed antenna is validated. The measured impedance bandwidth of 10 dB and the axial ratio (AR) bandwidth of 3 dB are wider than 13%. The peak gain is greater than 2.2 dBic, and the minimum AR is less than 1.1 dB, with the symmetrical and stable radiation patterns. The antenna has the compact size of 60 × 60 × 15 mm3. The proposed antenna can not only meet the requirements of RFID handheld reader applications in universal ultra‐high frequency (UHF) band (840‐960 MHz), but also has the advantages of wideband, small size, lightweight, low cost, and simple structure. Therefore, the design has a good application prospect in the field of Internet of Things.

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In this study, the design of a one‐dimensional high‐gain beam‐scanning transmitarray fed by a phased array with continuous electronic scan and low scan loss is displayed and demonstrated. The feeding linear phased array realizes continuous beam scanning in one plane. And the transmitarray performs phase compensation along another plane to increase the gain. The traditional array‐fed scanning transmitarray has homogeneous phase compensation in one direction. Differently, the phase compensation in the proposed method is carefully designed considering that the beam is scanning. By designing the phase distribution of the transmitarray column by column, the scan loss is successfully reduced. The experimental results of a designed scanning transmitarray fed by a phased array without feeding network show the peak gain of 22.76 dBi and the scan loss of only 1.43 dB within the scanning range of ±35° at the centre frequency of 13.5 GHz. Hence, the advantages of continuous electronic scan, high gain, and low scan loss are validated. Moreover, by integrating the power divider and phase shifters into the feeding phased array, the measured gain increment of 8.26–9.89 dB and the scan loss of 1.74 dB within ±35° are obtained.