This paper reports a novel, cost effective, and compact ultra-wideband (UWB) antenna for applications in an unlicensed-frequency band of 3.1-10.6 GHz. To achieve the UWB operation, a novel concept of annular shapes, circular slot combinations, and partial ground is employed. Furthermore, the proposed antenna with novel configuration occupies an attractive size of only 18×12 mm² which allows compatibility with portable UWB application devices. This flower-horn shaped UWB antenna is printed on a cost-effective FR-4 substrate, which exhibits a dielectric-constant of 4.4 and a loss-tangent of 0.019. The fabricated prototype is experimentally tested, and measured results validate the design approach of presented UWB antenna. The measured results confirm its UWB characteristics covering 3.1-11.2 GHz with S₁₁ ≤ -10 dB. Also, a maximum peak-gain of 5.05 dBi at 9 GHz and a minimum radiation-efficiency of 94.35% are noted in the full operating-band. A good agreement has been obtained between the simulated and measured results in terms of reflection-coefficient, gain, radiation-efficiency, radiation patterns and group delay which confirm the suitability of suggested small printed antenna for the intended UWB applications.....

This work studies the correlation between 14-elements of a sub-6 GHz MIMO antenna for mobile terminal, operating in the 3.10 to 3.85 GHz frequency band. Envelope correlation coefficient (ECC) was used to assess the relationship between MIMO antenna elements. A total of 91 ECC values were considered at every frequency point for the 14-element antenna, which was performed under two propagation scenarios: (i) a uniform environment, and (ii) a Gaussian environment. For the latter, three angular spreads (AS) of 20˚, 30˚, and 40˚ and incident angle of every 10˚ in both elevation and azimuth coordinates are considered. The resulting ECC in the uniform environment is below 0.15 over the entire operating frequency band, indicating that the 14 elements are minimally correlated. However, in a Gaussian environment, the ECC is evaluated at 3.25 GHz. For the AS values of 20˚, 30˚, and 40˚. The average number of ECC values below the 0.3 threshold is 48, 67, and 81 out of 91 total ECC values, respectively. Finally, a relation is derived between the number of ECC values below 0.3 and the lowly-correlated number of antenna elements. It is seen that at a wider angular spread of 40˚, the number of equivalent lowly-correlated elements is 12 with 87% from all considered incident wave directions. ....

This article presents a dipole antenna using an I-shapes adding technique on both sides of the antenna's body. To increase the using frequency range to be wider, with horn waveguide for gain enhancement and harvest energy by matching circuit. Which is compatible with the voltage multiplier circuit at RF frequency (510-790 MHz) in a TV digital system. When taken to measure the effect of the antenna, it was found that the antenna operates at a frequency range of 60.24% (450-838 MHz), a 67.79% increase from the base dipole antenna, which has the gain enhancement of 10.23 dB from adding the horn waveguide 60.99%. By has a pattern of energy radiating in a specific direction, and when the antenna is used with an energy harvesting circuit to get energy or power from the front direction of the TV digital antenna at a distance of 10 km, capable of harvesting energy up to 7.33 uW.....

A novel dual-band filter power divider (DB-FPD) with controllable transmission zeros (TZs) is designed using a slotline multimode resonator (SLMR) in this letter. Using the stub loading technology, each resonator mode of the SLMR can be easily controlled. Accordingly, a dual-band bandpass filter is realized. Four TZs are generated due to the loaded stubs on the SLMR and feeding network, which can improve the out-of-band selectivity. Finally, without introducing additional circuits, a DB-FPD with good performance is realized. For verification, a prototype operating at 2.01 and 4.79 GHz is fabricated and measured. The measured results are basically consistent with simulated ones. The 3-dB fractional bandwidths are 29.7% (1.72~2.32 GHz) and 7.99% (4.58~4.96 GHz), respectively, and the isolation in each band is better than 14 dB.....