An Integrated Filtering Antenna Array With High Selectivity and Harmonics Suppression

IEEE Trans. Antennas Propagat.

Wang

2017

Self Cite

101

Abstract-A novel method of achieving low-profile, broadband microstrip array antennas with high antenna gain is proposed for millimeter-wave (mm-wave) applications. The element employs a novel 3 rd -order vertically coupled resonant structure that a U-slot resonator in the ground is used to couple with the feeding resonator and the radiating patch, simultaneously. This proposed structure can significantly improve the bandwidth and frequency selectivity without increasing the thickness of the antenna. Then, to achieve the subarray, a new wideband power divider with loaded resonators is employed, which can be used to further improve the bandwidth. To demonstrate the working schemes of broadside radiation and scanned beam, two 4 × 4 array antennas are implemented on the same board. Measured results agree well with the simulations, showing a wide bandwidth from 22 to 32 GHz (FBW = 37%) with the gain of around 19 dBi. The beam scanning array can realize a scanning angle of over 25 degrees over a broadband. In addition, due to the filtering features are integrated in the design, the proposed antenna could also reduce the complexity and potential cost of the frontends.Index Terms-Broadband, beam scanning, filtering, millimeter-wave, antenna array, antenna, 5G. I. INTRODUCTIONThe emerging fifth-generation (5G) mobile communication has attracted intensive research interests in academia and industry because of its huge potentials such as high data rate and significant reduction of digital traffic [1]- [2]. In the 5G era, lots of things such as electronic devices, vehicles and the equipment in the offices and homes will be wirelessly connected through the Internet. Users will be able to access ultra-high-definition (UHD) multimedia streaming and services such as Virtual Reality (VR) and Augmented Reality (AR) [2]. All these potential services will inevitably demand a very wide bandwidth to support the extremely high data rate in 5G wireless communication. The millimeter wave (mm-wave) frequency band is widely believed to be a good candidate to realize a wideband operation.For mm-wave applications, other problems to be concerned are the higher transmission loss and link stability, which could be overcome by increasing the gain and adopting the adaptive directional beam [2]. Massive MIMO base station is a promising technique for improving the capacity and service quality by accurately concentrating the transmitted energy to the mobile users [3]- [5], as the architecture shown in Fig. 1. The massive MIMO antenna has multiple antenna subarrays in two dimensions and each can adaptively direct the beams to the users in azimuth and elevation directions. Thanks to each subarray is composed of n × n radiation elements, high antenna gain and steerable beam can be achieved. Due to the short wavelength at mm-waves and limited coverage of each 5G cellular, the mm-wave base-station antennas with low cost, low profile and light weight will be in huge demand in urban areas.To date, several mm-wave antennas have been reported for 5G commun...

Section: Introductionmentioning

confidence: 99%

Broadband High-Gain Beam-Scanning Antenna Array for Millimeter-Wave Applications

Mao

IEEE Trans. Antennas Propagat.

Wang

2017

Self Cite

101

Section: Equivalent Circuit Modeling Of Filtering Antenna System For mentioning

confidence: 99%

“…Up to date, the objective of most research on filtering antennas is to improve the frequency selection in wireless communication systems and only focus on the frequency response and patterns. [9][10][11] However, it cannot meet the requirements of the rectenna in RF energy harvesting. Here, we explore the filter matching network theory to design and FIGURE 1 Wearable systems with RF harvesting analyze the broadband filtering antenna with specific filter performance and arbitrary complex input impedance.…”

Section: Equivalent Circuit Modeling Of Filtering Antenna System Fomentioning

confidence: 99%

Filtering antennas for energy harvesting in wearable systems

Dong

Int J Numerical Modelling

Luo

et al. 2019

Self Cite

Wearable systems are important for future smart home care for the disabled and ageing population. One of the key challenges is the power supply. One solution is to develop an energy harvesting system suitable for providing power wirelessly. The matching network and filter in traditional energy harvesting system occupy lots of space, introduce additional losses, and reduce the total efficiency. This paper presents a novel filtering antenna suitable for wearable energy harvesting systems. The developed antenna has a broadband operation, harmonics suppression, compact size, and low cost. Firstly, a novel technique for broadband filtering antenna modeling and design in order to realize complex input impedance is presented. By adjusting the external quality factors and coupling coefficients of the resonators, complex impedance matching can be realized. Then, the theory of characteristic mode is used for the modal analysis of the filtering antenna. To verify the design concept, a C‐band circularly polarized filtering antenna with complex impedance is designed and fabricated. The results show that the impedance bandwidth is more than 14.5% with a peak gain higher than 8.5 dBi. The proposed antenna is conjugate matched to the rectifying circuit at 5.8 GHz and mismatched at the second harmonic frequency to suppress the harmonic reradiation, leading to a compact rectenna structure.

“…A wide impedance bandwidth from 7.2 to 9 GHz (22%) is achieved. This broadband performance is attributed to the integrated resonators and the stacked configuration, which renders a strong coupling between the feed and the patch [21]- [22].…”

Section: B X-band Element and Generation Of Cpmentioning

confidence: 99%

Dual-Band Circularly Polarized Shared-Aperture Array for $C$ -/ $X$ -Band Satellite Communications

Mao

IEEE Trans. Antennas Propagat.

Wang

et al. 2017

Self Cite

149

Abstract-A novel method of achieving a single-feed circularlypolarized (CP) microstrip antenna with both broad impedance bandwidth and axial ratio (AR) bandwidth is presented. The CP characteristics are generated by employing a resonator to excite the two orthogonal modes of the patch via two coupling paths and the required 90 o phase difference is achieved by using the different orders of the two paths. The presented method, instead of conventional methods that power dividers and phase delay lines are usually required, not only significantly enhances the bandwidths of the antenna, but also results in a compact feed, reduced loss and high gain. Based on this method, a dual-band shared-aperture CP array antenna is implemented for C/X-band satellite communications. The antenna aperture includes a 2 × 2 array at C-band and a 4 × 4 array at X-band. To accommodate the C/X-band elements into the same aperture while achieving a good isolation between them, the C-band circular patches are etched at the four corners. The measured results agree well with the simulations, showing a wide impedance bandwidth of 21% and 21.2% at C-and X-band, respectively. The C-and X-band 3-dB AR bandwidths are 13.2% and 12.8%. The array also exhibits a high aperture efficiency of over 55%, low side-lobe (C-band: -12.5 dB; X-band: -15 dB) and high gain (C-band: 14.5 dBic; Xband: 17.5 dBic).