This communication presents a beamforming shaped-beam satellite (SBS) antenna based on a phased array technique and a boosted-beam control. The presented SBS antenna is specifically designed to cover the whole Korea regions including the southern and northern areas. The proposed SBS antenna consists of waveguide feed network, beamforming circuits, waveguide circular polarizers, 19 radiation elements and a boosted-beam control panel with active component calibration for temperature variation. In order to maximize the flexible performance, boosted-beam mode is supported to meet the required high power signal regardless of bad weather conditions. The adjustable effective isotropic radiated power (EIRP) range was around 6 dB and there are total 19 beamforming units each configured by drive amplifier, phase shifter and attenuator. Also, one extra beamforming unit synchronized with the other 19 elements is integrated for active component calibration. Each beamforming element can control relative phase shift up to 360° with 5° step and relative amplitude variation up to 10 dB with 1 dB step as well. Also, each radiation element is configured by waveguide horn and the return losses were better than 25 dB at 21 GHz.

This paper proposes a pattern reconfigurable high gain spherical dielectric resonator antenna (DRA) operating on higher-order mode. Two microstrip patches were used to excite TE301 mode in the different direction. A reconfigurable switch network was designed and it has three switching modes for selecting each patch alone or selecting them simultaneously. The proposed antenna can reconfigure its radiation pattern by using a feeding structure which is consist of two microstrip patches and the reconfigurable switch network. A prototype antenna operating on TE301 mode at 5.8GHz was fabricated by ceramic material. By experiment, we validated the new concept of pattern reconfigurable spherical DRA.

This letter proposes a frequency-reconfigurable dipole antenna using an origami flasher. The dipole antenna is designed on flat paper in the unfolded state, and the paper can then be folded into a cube inspired by the origami flasher. Dipole length is extended in the folded state due to the patch pole, which acts as a dummy in the unfolded state. The proposed origami antenna can switch resonance frequency from 1.23 to 0.77 GHz by folding the paper. Measured return losses are 11.6 and 13.9 dB, peak gains are -0.48 and -3.41 dBi, and efficiencies are 90% and 20% at each resonance frequency in the unfolded and folded states, respectively.

Localization has been extensively studied owing to its huge potential in various areas, such as Internet of Things, 5G, and unmanned aerial vehicle services. Its wide applications include home automation, advanced production automation, and unmanned vehicle control. In this study, we propose a novel localization method that utilizes convolutional neural network (CNN) and ultra-wideband (UWB) signals. A localization problem is converted to a regression problem with the proposed CNN, in which the ranging and positioning phases are integrated. By integrating the ranging and positioning phases, the proposed CNN estimates the location of UWB transmitter directly without any additional step. To integrate both phases of localization, a simple-yet efficient input image generation method is proposed. In the proposed input image generation method, three oversampled two-dimensional input images are generated from the three received UWB signals and they are provided to the designed CNN through the three channels, which are represented by red-, green-, and blue-color channels, respectively. The proposed CNN-based localization system then estimates the location of the UWB transmitter directly using the three-channel image as an input of the CNN. Simulation results verify that the proposed CNN-based localization method outperforms the traditional threshold-based and existing CNN-based methods. Also, it is observed that the proposed method performs well under an asymmetric environment, unlike the existing method.

This paper presents a wide-angle scanning phased array antenna using high gain pattern reconfigurable antenna (PRA) elements. Using PRA elements is an attractive solution for wide-angle scanning phased array antennas because the scanning range can be divided into several subspaces. To achieve the desired scanning performance, some characteristics of the PRA element such as the number of switching modes, tilt angle, and maximum half-power beamwidth (HPBW) are required. We analyzed the required characteristics of the PRA element according to the target scanning range and element spacing, and presented a PRA element design guideline for phased array antennas. In accordance with the guideline, the scanning range was set as ±70° and a high gain PRA element with three reconfigurable patterns was used to compose an 8x1 array antenna with 0.9 λ₀ spacing. After analyzing whether the active element patterns meet the guideline, the array antenna was fabricated and measured to demonstrate the scanning performance. The fabricated array can scan its beam from -70° to 70° by dividing the scanning range into three subspaces. It shows that even if the array antenna has large element spacing, the desired scanning performance can be obtained using the elements designed under the guideline.