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We have developed the first low-loss, dual-polarization, asymmetric Mach-Zehnder interferometer (AMZI) chip for phase-coding quantum key distribution (QKD) using silica planar lightwave circuit technology. The transmitter and receiver modules have a polarization extinction ratio greater than 20 and 15 dB, respectively. Using a birefringent Mach-Zehnder interferometer, a polarization beam splitter is integrated into the receiver chip, while the polarization rotation function is obtained via a half-wave plate thin film. The receiver chip is entirely passive and has an excellent fiber C fiber loss of 1.90 dB, while the transmitter’s AMZI contains thermo-optical electrodes for adjusting the output pulses’ relative phase and intensity ratio. The chips are evaluated to have an interference visibility of greater than 98% across a broad temperature range, demonstrating their suitability for quantum key distribution applications. [ABSTRACT FROM AUTHOR]

This article presents a ± 45° dual-polarized triple-band dipole antenna array for 5G base station applications. Each antenna element consists of three main parts: radiator, feeding baluns, and reflector. The profile antenna array is designed to cover two bands from n77 and one band from n79 5G NR frequency spectrum. The proposed antenna element and array are optimized with ANSYS 18.2 HFSS simulator and then fabricated and fully characterized. The obtained measured impedance bandwidths resulted in 3.6–3.75 GHz, 4.1–4.25 GHz, and 4.82–4.95 GHz, with a gain of almost 8.12 dBi and 70.7° half-power beam width (HPBW). Once characterized, such an elementary element has been used in the design, realization and test of a 1 × 8 antenna array that exhibited a measured gain 16.65 dBi with 69° HPBW respectively. The antenna array operates in 3.43–3.75 GHz, 4.13–4.30 GHz, and 4.80–4.95 GHz with 15 dB return loss. The triple-band dual-polarized feature with very high isolation, cross-polarization discrimination ratio (XPD) and front to back ratio (FBR) makes this profile antenna array a suitable candidate for 5G base station applications. [ABSTRACT FROM AUTHOR]

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In the present world, malignant growth in bosom is the commonly prevailing disease among women. Early bosom diagnosis and treatment are compulsory to diminish the death rates of bosom malignancy. Here, a dielectric differentiation is being detected among typical and malignant growth tissues, having applied ideal scope of frequencies. Winding radio wires becomes the most appropriate in this application due to its double polarization property where an adaptable substrate fulfils the wearable prerequisites. In this paper, the Winding Reception Apparatus is structured as a 4 × 4 exhibit with a goal that covers the greatest diameter of the bosom. The radio wire parameters such as expansion, direction and return misfortune are upgraded to get acceptable resistance, coordination and great reaction over the necessary recurrence. The receiving wires at the thickness 0.035 mm and with length, width of 19 mm and 15 mm are planned on an adaptable FR-4 substrate with a thickness of 0.4 mm. The proposed receiving wire cluster is structured and recreated in ADS programming for the recurrence scope of 2–4 GHz. In this regard, the obtained outcomes are contrasted and the foreordained qualities and nearness or non-appearance of the disease are distinguished. [ABSTRACT FROM AUTHOR]

A large dual-polarization microstrip reflectarray with China-coverage patterns in two operating bands is designed. To sufficiently compensate for the spatial phase delay differences in two operating bands separately, a three-layer rectangular patch element is addressed, which is suitable for the large dual-polarization reflectarray. Due to the complexly shaped areas and high gain requirements, there are more than 25 000 elements in the reflectarray, making it difficult to design, due to more than 150 000 optimization variables. First, the discrete fast Fourier transform (DFFT) and the inverse DFFT are used to establish a one-to-one relationship between the aperture distribution and the far field, which lays a foundation for optimizing the shaped-beam reflectarray. The intersection approach, based on the alternating projection, is used to obtain the desired reflection phases of all the elements at some sample frequencies, and a new method for producing a suitable initial solution is proposed to avoid undesired local minima. To validate the design method, a dual-polarization shaped-beam reflectarray with 7569 elements is fabricated and measured. The measurement results are in reasonable agreement with the simulation ones. Then, for the large broadband reflectarray with the minimum differential spatial phase delays in the operating band, an approach for determining the optimal position of the feed is discussed. To simultaneously find optimal dimensions of each element in two orthogonal directions, we establish a new optimization model, which is solved by the regular polyhedron method. Finally, a dual-band dual-polarization microstrip reflectarray with 25 305 elements is designed to cover the continent of China. Simulation results show that patterns of the reflectarray meet the China-coverage requirements in two operating bands, and that the proposed optimization method for designing large reflectarrays with complexly shaped patterns is reliable and efficient. [ABSTRACT FROM AUTHOR]

In this work, a novel single-feed stacked microstrip antenna is proposed for high gain and dual polarization application. The designed antenna is useful at two purposes. In one hand, its lower operating frequency demonstrates high gain and on the other hand, the upper operating frequency shows circular polarization. The proposed design consists of two pairs of small parallel slots on the radiating surface as well as in the ground plane with a view to achieving significant amount of gain (approximately 8.3 dB) at its lower operating frequency (~ 6 GHz). An interesting aspect of this work is its polarization diversity. The designed antenna is capable of showing circular polarization at its upper operating frequency (~ 6.8 GHz). At this frequency, the axial ratio of the antenna has been kept below 3 dB for circular polarization applications. This circular polarization has been introduced by truncating the corners of radiating patch at different shapes. High gain and dual polarization play a major role on different antenna performance parameters. This antenna meets these two applications simultaneously. A prototype has been fabricated and characterized in order to validate the results. An outstanding agreement between experimental results and simulated results is achieved. [ABSTRACT FROM AUTHOR]

The progress in dual-band dual-polarization (DBDP) shared-aperture antennas for the synthetic aperture radar (SAR) application in the last decade is reviewed. Several designs of DBDP SAR antenna arrays are introduced with their main performances, then their comparison is summarized. In addition, some techniques enhancing DBDP antenna performances are presented. [ABSTRACT FROM AUTHOR]

An 8 × 1-element wideband dual-polarized slot-coupled microstrip antenna array with high isolation and low cross-polarization in X-band is presented. The array antenna offers an impedance bandwidth (VSWR≤2) of 23% and 21% for dual polarization ports, respectively. The measured isolation between two polarization ports is better than 35 dB and the measured cross-polarization level below −25 dB in the main beam over the operation frequency band of 9.35 GHz to 9.75 Ghz. This array is well suitable for X-band SAR (synthetic aperture radar) antenna application. [ABSTRACT FROM AUTHOR]

Recently, accelerating advances in coding metasurfaces linking metamaterial and digital codes have enabled unexampled route for electromagnetic (EM) waves manipulation, including perfect reflection and transmission. In this paper, an anisotropic coding metasurface with a semi-discontinuous metallic ground sheet are proposed, which realizes dual independent functionalities by changing the polarization of incident waves. The ultrathin metasurface is composed of eight coding elements based on a simple rectangle metal patch and the reflective phases of these elements fully cover 360°. Both numerical and measured results show that our design is able to near-perfectly reflect the normally incident y-polarized wave to desired reflection angle and transmit the y-polarized plane wave with high efficiency. In addition, considering the simple structure, easy fabrication process and decent control ability on EM waves, the proposed coding metasurface may be exploited for more complex functionalities. [ABSTRACT FROM AUTHOR]

A wideband dual-polarized slot-coupled stacked microstrip antenna with very high isolation and low cross-polarization is presented. To improve isolation between two polarization ports, the stacked patches are excited by an open-ended and a T-shaped micros-trip lines both via two H-shaped slots placed in a “T” configuration. The measured isolation is better than 40.5 dB over the bandwidth from 8.8 to 9.8 GHz with cross-polarization level less than −28.5 dB. The measured VSWR⩽2 bandwidths reach 20.7% and 19.1% at the vertical and horizontal polarization ports, respectively. This antenna is suitable to be used as array elements in spaceborne synthetic aperture radars (SAR) and active phased array radars. [ABSTRACT FROM AUTHOR]