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This paper presents a low-profile magneto-electric (ME) dipole antenna with an enhanced impedance bandwidth realized by the loading of shorting parasitic elements. The antenna contains a horizontal planar electric dipole antenna, a $\Gamma $ -shaped shorted patch antenna, a pair of parasitic L-shaped shorted patches, and a direct feed. By loading of the parasitic L-shaped patches such that they are shorted to the ground, the proposed antenna attains a significant bandwidth enhancement while maintaining excellent broadside radiation characteristics. An antenna prototype with a low profile of only $0.11\lambda _{0}$ was fabricated and tested ( $\lambda _{0}$ is the free-space wavelength referring to the center frequency). The antenna achieves a measured impedance bandwidth of 75.64% (1.34–2.97 GHz) for a voltage standing wave ratio (VSWR) of less than 2. Within the operating band, the measured gain ranges from 6.23 to 8.49 dBi. Additionally, stable radiation patterns on both E- and H-planes with a high front-to-back ratio of more than 20.5 dB are achieved.

A compact wideband internal antenna based on an epsilon negative (ENG) zeroth-order resonator (ZOR) is proposed to operate in the ultra-high frequency (UHF) band (470–771 MHz) for ultra-high-definition television (UHD-TV) applications. The antenna having a compact size of 9 × 220 mm2 is placed on the top edge of the 49-inch TV model. The bezel frame of the TV model is used as the substrate of the antenna. The antenna is fed by a coplanar waveguide with a ground plane (CPWG). A shorting plate was added to expand the ground plane of the CPWG structure to achieve resonance at lower frequencies. The ENG structure is formed by a meander line that generates zero-order resonances at higher frequencies in the UHF band. Based on analysis, the proposed antenna is fabricated and tested. The measurement results show that the reflection coefficient (S11) is under − 6 dB in a wide frequency range from 440 to 910 MHz covering the entire UHF band. The fractional bandwidth is extended up to 69% with a peak gain of 4.8 dBi, and the average radiation efficiency of the antenna is 75%.

An internal reconfigurable Dipole–Loop antenna array, covering the entire ultra-high frequency (UHF) band for ultra-high definition television (UHD-TV) applications is presented. The internal antenna array is used to overcome the influence of electromagnetic interference when integrating the antenna element inside the TV model and to increase the gain and reception rate of receiving signals for television broadcasting. The antenna array is designed based on the Dipole–Loop antenna elements, placing on substrate material PC-ABS (polycarbonate-acrylonitrile butadiene styrene: er = 3.5, tan δ = 0.005) of the bezel frame in the TV model. By simultaneously switching PIN diodes with two ON/OFF states, the antenna array can be frequency reconfigured to achieve a wide operating bandwidth for UHF (470–771 MHz) band. The spacing between the antenna elements in the array at each mode is chosen as 0.5λ0 (λ0 represents the free space wavelength of the highest frequency in the operating band). The proposed antenna array is designed, fabricated, and tested for experimental verification. Measurement results show that the antenna array is good for high reception rate of UHD-TV applications, with a − 6 dB impedance bandwidth of 51.6% (460‒780 MHz), covering the whole UHF band. The 3 dB gain bandwidths of 42.5% and 54.6% are obtained with peak realized gains of 9.6 dBi and 8.5 dBi for the horizontal and vertical polarizations, respectively. In addition, the diversity performance parameters are obtained and evaluated using the mean effective gains of the elements, and the diversity gain using both simulation and measurement results. It shows that the proposed antenna array can receive multi-side signals, applied in diversity and MIMO systems.

In this study, an internal antenna integrated into a 49-inch TV model is presented, operating in the ultra-high frequency (UHF: 470‒771 MHz) band for signal reception in ultra-high definition television (UHD-TV) applications. The design of the proposed antenna has encountered major challenges such as relatively narrow impedance bandwidth, limited space, the effect of material properties, and the electromagnetic interference from the other components inside the TV that deteriorate the performance of the antenna considerably. The antenna is positioned directly on the bezel frame (made of polycarbonate-acrylonitrile butadiene styrene: ԑ r = 3.5, tan δ = 0.005) of the TV model as the substrate for the antenna. A monopole-type antenna is chosen to easily implement along the long side of the bezel frame in a very narrow spacing between the display and the casing of a TV (∼2.5 mm). Combined with a sleeve feed, tapered line, and parasitic strips, the proposed internal antenna exhibits a wideband impedance characteristics. The measured results show that a radiation efficiency of higher than 70% and a peak gain of 4.8 dBi are obtained over the operating frequency range of 430‒940 MHz (relative bandwidth of 75%), which cover the entire UHF band. These results indicate that the proposed antenna is very suitable for UHD-TV applications.

This study presents the implementation of an internal antenna for ultra-high-definition televisions (UHD TVs), which has encountered challenges such as inherently narrow impedance bandwidths, limited space, and the effect of material properties of the TV to the antenna performance. The proposed antenna consists of a pair of rectangular arms (the dipole mode), which are fed by the coaxial cable, these arms are also connected to the ground plane (the loop mode) through two shortings that excite an additional resonance mode. In addition, reconfigurable antennas also offer attractive potential solutions to solve the challenging antenna problems related to narrow bandwidth using the ability to switch and tune operation frequency. Herein, a frequency reconfigurable dipole–loop antenna which can cover the entire ultra-high-frequency band (UHF: 470–771 MHz, BW: 47.4%) is achieved using PIN diodes for switchable frequency and varactor diodes for tunable frequency. A 49-inch UHD TV is used for the practical implementation experiment. The TV bezel ( ԑ r = 3.5, tan δ = 0.005) is used as the substrate for the antenna design. The designed antenna for UHD TV applications achieves good impedance matching and stable radiation characteristics in the UHF band, considering S 11 = − 6 dB (VSWR 3:1) as the impedance matching criterion.

A simple internal antenna that combines a planar inverted F antenna (PIFA) and a loop antenna to achieve wideband (BW ∼ 48%) operation in ultra-high frequency (UHF: 470–771 MHz) band for digital television (DTV) applications is presented. The design allows the installation of an antenna within a TV model, thereby addressing the limitations of space. The 49-inch DTV is used for the practical implementation experiment. The TV bezel (made of polycarbonate-acrylonitrile butadiene styrene (PC-ABS): er = 3.5; tan δ = 0.005) is used as the substrate for the antenna design. The antenna is placed on the top edge of the TV model. With the combination of the PIFA mode and loop mode operations, the operating bandwidth of the proposed PIFA-loop antenna is significantly broadened. The measured results show that the proposed antenna has wide bandwidth of about 410 MHz (460–870 MHz) and suitable radiation performance with higher than 2.2 dBi of peak gain and 47% of efficiency within the operating bandwidth.