Dual-polarized Hybrid Research Articles

Multiband Dual-Polarized Hybrid Antenna With Complementary Beam for Simultaneous RF Energy Harvesting and WPT

A novel hybrid antenna for simultaneous RF energy harvesting (RF-EH) and dedicated wireless power transfer (WPT) is proposed. The hybrid antenna consists of a multiband dual-polarized omnidirectional antenna element (covering GSM-1800, UMTS-2100, ISM-2400/5800, 5G-3500, and wireless local area network (WLAN) bands) and a 2.4 GHz dual-polarized high-gain directional patch array element. In the WPT band (ISM-2400), directional beams locate at the null of omnidirectional beams, and a pair of spatially complementary beams is obtained. The omnidirectional beams are capable of capturing the ambient RF energy from low-elevation space for low-power circuits, while the directional beams receive the power from a dedicated source to activate high-power modules. Also, the spatially complementary feature contributes low mutual couplings between ports that support the independent operation of WPT and RF-EH. For validation, an outdoor RF-EH test and an indoor WPT test are conducted. The measured results agree with the simulated ones.

Total Cost of Ownership Optimization for Direct Air-to-Ground Communication Networks

Aircraft cabins are one of the last venues without mobile broadband. Considering future 5G applications and connectivity requirements, direct air-to-ground communications (DA2GC) is the only technique which can provide high capacity and low latency backhaul link for aircraft via a direct communication link. To this end, we propose an analytical framework to investigate the ground station deployment problem for DA2GC network employing multi-user beamforming with dual-polarized hybrid DA2GC antenna arrays. In addition, the proposed framework is utilized to analyze and optimize the total cost of ownership (TCO) of the DA2GC network to provide coverage for European airspace. We present the interplay between different network parameters: the number of ground stations, array size, transmit power and bandwidth, and TCO optimizing deployment parameters are calculated in order to satisfy capacity requirements. At the end, we show that, depending on the cost of different network resources, a terrestrial cellular network can be designed to cover the whole European airspace with limited number of ground stations with a certain array size, i.e., 900 and 361 antenna elements for ground station and air station, respectively.

Formalism of Compact Polarimetric Descriptors and Extension of the $\Delta\alpha_{\text{B}}/\alpha_{\text{B}}$ Method for General Compact-Pol SAR

Compact polarimetry is a dual-polarization hybrid imaging mode and provides partially backscatter characteristics of scatterers. The compact polarimetric (CP) synthetic aperture radar (SAR) measures the combinations of fully polarimetric (FP) scattering coefficients, which is dependent on the transmit-wave polarization state. The backscattered wave is fully described by a 2-D complex scattering vector, in which the dual-channel polarization ratio represents the vector nature for describing target polarimetric properties. However, due to the dependence of CP measurements on the transmit wave, the complex channel ratio is explained differently for the same scatterers under different observation modes, e.g., the channel ratio $\rho =\pm j$ under the left circular mode and $\rho =\pm 1$ under the linear $\pi /4$ mode for the canonical trihedral and dihedral scatterers. The explanation diversity is inconvenient for the use of CP data, resulting in nonunified target decomposition algorithms. In this study, first, we propose a new formalism method for the general CP SAR mode, such that all CP mode observables are described based on the same standard for target scattering characterization. This provides potential for developing unified CP decomposition algorithms. Then, based on this formalism, a polarization ratio-based scattering characterization method is proposed, which is mathematically equal to the FP $\Delta \alpha _{\text {B}}/\alpha _{\text {B}}$ method but without any scattering assumption. Theoretical analyses and discussions are provided. Experiments show that the proposed method is efficient for compact polarimetric scattering interpretation.

Investigation of signal power splitting ratio for BPSK homodyne receiver with an optical Costas loop

We demonstrate influences of the power splitting ratio of the quadrature-arm to the input signal on both receiver sensitivity and residual phase error for a 10-Gb/s binary phase-shift keying coherent receiver based on an optical homodyne Costas loop. Fine adjustment of the signal power splitting ratio (Ks) is realized by tuning the polarization state of the input signal light of a dual-polarization optical 90-deg hybrid, leading to the precise control of the power distribution on two orthogonal states of polarization that are used for in-phase and quadrature arm, respectively. When the phase error is negligible (<10 deg) under different Ks, the sensitivity is improved by 2.65 dB and the Ks is optimized around 0.05. Based on loop bandwidth maintaining, the requirement on laser linewidth is also relaxed, i.e., 5.26 times larger linewidth is permitted at Ks = 0 . 05 than that without loop bandwidth maintaining. To fully utilize the signal light power and to avoid excess losses of the dual-polarization hybrid, homodyne Costas coherent receiver with a free-space optics-based 90-deg hybrid is also proposed. All experimental and theoretical results demonstrate the potential of approaching shot noise limited sensitivity for a Costas coherent receiver with an optimum Ks. It is significant to increase power budget and transmission span for satellite optical communication and free-space optical communication.

Carbohydrate-protein interactions characterized by dual polarization hybrid plasmonic waveguide

Abstract Optical biosensors present good performance for the affinity analysis of a molecular binding event. However, most of those excited with single optical mode are “blind” to the conformational change of bound molecules. We theoretically demonstrate a dual polarization hybrid plasmonic (DPHP) waveguide with nano-slots. By addressing the structure with dual polarizations, the optogeometrical properties (density and thickness) of protein layers have been determined without ambiguity. Differences in the hybrid mode dispersion between the transverse electric (TE) and transverse magnetic (TM) modes allow to separately determine the thickness and the density at all stages during the molecular interaction. In addition, nano-slots can be equated with an effective optical capacitance resulting in a strong field confinement; thereby, subtle changes in the ambient medium can be sensed. A proof of concept is conducted by analyzing the conformational change of HepV, a recombinant fragment of collagen V, during complicated molecular interaction. Integrated with adlayer thickness and density, we can conclude that a thick sparse layer formed after heparin capture and a thin dense layer arising from HepV bound. Accordingly, HepV undergoing conformational change has been traced and verified as molecular interaction occurs.

Dual-band dual-polarized hybrid aperture-cylindrical dielectric resonator antenna for wireless applications

Dual-band dual-polarized hybrid aperture-cylindrical dielectric resonator antenna for wireless applications

Eight-Port Orthogonally Dual-Polarized Antenna Array for 5G Smartphone Applications

A dual-polarized hybrid eight-antenna array operating in the 2.6-GHz band (2550–2650 MHz) for 5G communication multi-input multi-output (MIMO) operation in the smartphone is presented. The proposed hybrid antenna array elements are symmetrically placed along the long edges of the smartphone, and they are composed of two different four-antenna array types (C-shaped coupled-fed and L-shaped monopole slot) that exhibit orthogonal polarization. Therefore, coupling between the two antenna array types can be reduced, and the MIMO system performances are enhanced. A prototype of the proposed eight-antenna array is manufactured and measured. A good impedance matching (10 dB return loss or better), desirable cross-polarization discrimination (better than 15 dB), and an acceptable isolation (better than 12.5 dB) are obtained. Envelope correlation coefficient and channel capacity are also calculated to evaluate the MIMO performances of the proposed antenna array.