A 5G rotated frame radiator for multiple applications is presented in the following paper. The presented geometry is capable of radiating the large frequency band from 2.91 to 12.17 GHz, which covers the 5G-(I) sub-6 GHz band, X-band communication with high efficiency. The impedance bandwidth of the radiator is 128%, with an electrical size of 0.24 λ × 0.24 λ × 0.15 λ in lambda. The antenna is simulated with an FR4 substrate using CST Simulator. 06-stages evolution process is also investigated by simulations, and corresponding S-parameter results are presented. Antenna's design comprises a patch in a rotated square fractal-like frame fed by a microstrip line. The proposed structure also demonstrates stable radiation patterns across the operating bandwidth. The proposed radiator has a high gain of 3.8 dBi, and an efficiency of 85%, which claimed that UWB range of the designed antenna. Therefore, it is useful for 5G-(I) sub-6 GHz band, X-band applications, including mobile, radar, and satellite microwave communication.

A compact antipodal Vivaldi antenna with superwideband characteristics is presented in this paper. For improved matching of input impedance at lower frequency region, techniques like binomial tapering of outer edges, binomial slit loaded outer edge, and protruded binomial tapered stub loading have been adopted. The antenna operates in a wide frequency range from 2 to 20 GHz. Experimental results show, stable radiation pattern with peak realized gain of more than 8 dBi, group delay within 1 ns, 164% fractional bandwidth, radiation efficiency of more than 90%, which are in good agreement with the simulated results. The compact size of the proposed antenna (1.14λ0 × 1.21λ0) with wide frequency bandwidth and directional radiation characteristics make it suitable for through-wall radar and medical imaging applications.

Nowadays, as indoor localization is getting more popular, there is a growing need for reliable and accurate techniques of position determination. Recently, ultrawideband (UWB)-based systems are gaining popularity, since they make achieving positioning errors in the range of dozens of centimeters or even single centimeters, possible. The Time Difference of Arrival (TDOA)-based systems are especially attractive because they allow to simplify tags, in which functionality can be limited to transmission of packets. However, one of TDOA-based solution drawbacks is a need for strict synchronization between anchor nodes, which may be hard to provide in indoor environment. In the paper, a novel method for simplifying synchronization in TDOA-based UWB localization system is described. The paper presents two system architectures based on pairs of synchronized nodes. Results of simulations and experiments included in the article allow for evaluation of both solutions.