Dual-polarization Research Articles

Simulation Verification and Testing of Dual Circular Polarization Diversity

This paper presents a test method of satellite communication based on dual circular polarization diversity. A polarized channel model is established based on two validated models to obtain the bit error rate curve of MIMO system. Moreover, the specific antennas are chosen through the simulation result of the cross-polar discrimination (XPD). Finally, a hardware platform with USRPE310 and polarized-antenna is established to verify the simulation result.

Low-cost Arduino controlled dual-polarity high voltage power supply

Ion Mobility Spectrometry (IMS) provides low ppbv detection limits for gas-phase or aqueous analytes. These instruments rely an electric field to produce ion motion. This electric field is typically 200–600 V/cm with a 15 cm cell, requiring an HV source of 6–10 kV. In this work, we present a low-cost alternative for supplying this high voltage. Inexpensive, commercially available 0–20 kV HV modules are mapped to an analog 0–5 V input signal, controlled using an Arduino microcontroller and digital analog converter. Dual polarities are selectable through a front-panel switch and ramps potentials between settings to avoid damage to attached devices.

An SWB MIMO Antenna with Dual Band Rejection and Polarization Diversity for Ultra-Wide Band Applications

An SWB MIMO Antenna with Dual Band Rejection and Polarization Diversity for Ultra-Wide Band Applications

Dual-Band Ultrathin Polarization Converter for S-Band Microwave Transmission

In this letter, a low-profile dual-band frequency selective surface (FSS) is designed as a polarizer for satellite communication. This single-layered FSS with a meandered open loop intersected by a metallic strip behaves as a dual sense polarizer. It converts linearly polarized (LP) EM waves of frequency range 2.01–2.64 GHz into left-hand circularly polarized (LHCP) EM waves. Similarly, the LP waves in the frequency range of 3.26–3.68 GHz are converted into right-hand circularly polarized (RHCP) EM waves. The unit cell dimension of the compact polarizer is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.075\lambda _{0} \times 0.075\lambda _{0} \times 0.005\lambda _{0}$ </tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> stands for free space wavelength at the lowest cut-off frequency. This study explores the structural design evolution of the proposed polarizer and verifies the frequency behavior of the structure using a circuit model. The simulated performance of the dual-band polarizer is experimentally tested. Good concordance is observed between the simulated and measured results.

Coherent Driver Modulator With Flexible Printed Circuit RF Interface for 128-Gbaud Operations

We developed a flexible printed circuit (FPC) RF interface InP-based high-bandwidth coherent driver modulator (CDM) for 128-Gbaud class operations. To increase the bandwidth of the CDM, an FPC RF interface was introduced to the CDM package, which significantly improved the roll-off frequency by about 40 GHz compared with a conventional package with a surface-mount-type RF interface. The FPC package has a 3-dB bandwidth of about 75 GHz and roll-off frequency above 110 GHz. These are the best characteristics among the CDM packages reported so far. By integrating a modulator with an electro-optic (EO) 3-dB bandwidth of >67 GHz and a driver IC with an electrical 3-dB bandwidth of >75 GHz in this package, the CDM had an EO 3-dB bandwidth of >72 GHz. This EO 3-dB bandwidth is sufficient for 128 Gbaud-class operations. Furthermore, we performed 128-Gbaud dual polarization 16QAM modulations and confirmed good back-to-back bit-error-rate characteristics.

SEPIA345: A 345 GHz dual polarization heterodyne receiver channel for SEPIA at the APEX telescope

Context. We describe the new SEPIA345 heterodyne receiver channel installed at the Atacama Pathfinder EXperiment (APEX) telescope, including details of its configuration, characteristics, and test results on sky. SEPIA345 is designed and built to be a part of the Swedish ESO PI Instrument for the APEX telescope (SEPIA). This new receiver channel is suitable for very high-resolution spectroscopy and covers the frequency range 272–376 GHz. It utilizes a dual polarization sideband separating (2SB) receiver architecture, employing superconductor-isolator-superconductor mixers (SIS), and provides an intermediate frequency (IF) band of 4–12 GHz for each sideband and polarization, thus covering a total instantaneous IF bandwidth of 4 × 8 = 32 GHz. Aims. This paper provides a description of the new receiver in terms of its hardware design, performance, and commissioning results. Methods. The methods of design, construction, and testing of the new receiver are presented. Results. The achieved receiver performance in terms of noise temperature, sideband rejection, stability, and other parameters are described. Conclusions. SEPIA345 is a commissioned APEX facility instrument with state-of-the-art wideband IF performance. It has been available on the APEX telescope for science observations since July 2021.

Sea surface temperature retrieval based on simulated space-borne one-dimensional multifrequency synthetic aperture microwave radiometry

The space-borne one-dimensional multifrequency synthetic aperture microwave radiometer (1D-MSAMR) offers new possibilities for detecting high spatial resolution sea surface temperature (SST). To achieve higher SST retrieval accuracy, an SST retrieval algorithm, the two-step retrieval algorithm (TSSR), is proposed based on the multiple linear regression (MLR) algorithm. In this study, we investigated the SST retrieval accuracy of 1D-MSAMR based on simulation experiments. For the study, we assumed that the frequencies of the 1D-MSAMR were 6.9, 10.65, 18.7, 23.8, and 36.5 GHz, and that all frequencies worked in a dual polarization (vertical and horizontal) manner. We used an ocean-atmosphere microwave radiation brightness temperature model and the 1D-MSAMR simulator to simulate the measured brightness temperature based on WindSat data provided by the Remote Sensing Systems (RSS). An MLR algorithm and the TSSR were then developed to retrieve the SST within the incidence angle range of 0°–65°. The results show that the SST retrieval errors of the two SST retrieval algorithms decreased with the increase of incidence angle. The TSSR had higher retrieval accuracy, especially at low incidence angle. The average retrieval accuracy of the TSSR was about 0.3 K higher than that of the MLR algorithm. The retrieval error of the TSSR was also less sensitive to the measurement error of the 6.9 GHz frequency than the MLR algorithm.

Snow Depth Inversion in Forest Areas from Sentinel-1 Data Based on Phase Deviation Correction

At present, snow depth inversion based on active microwave remote sensing is concerned essentially with areas having a relatively simple underlying surface. The existence of forests reduces the sensitivity of microwaves to snow, which often makes the snow depth inversion results uncertain. This paper presents a snow depth estimation algorithm for forest areas by introducing a forest phase to characterize the effect of forests on backscattering electromagnetic wave. Firstly, the interferogram is generated with the differential interference of two-pass master-slave Synthetic Aperture Radar (SAR) images, and the real phase under snow cover condition is obtained by phase unwrapping. Secondly, the phase models for forest and non-forest areas are constructed. The effects of forest cover are modeled as forest phase in the forest phase model, which is estimated under the assumption of snow depth consistency on both sides of the boundaries between forest and non-forest areas. Finally, snow depth is estimated by the snow phase-depth model. The correctness of the proposed forest snow depth inversion algorithm was verified by taking the Jiagedaqi area of Greater Xing’an Mountains as the study area and sentinel-1 dual polarization images as the data source. Finally, the snow depth distribution of the study area was obtained with a spatial resolution of 30 m on 7 December 2020. The experimental results show that the snow depth values estimated in Jiagedaqi area are mainly between 40–120 cm, and the average snow depth value is 80.27 cm. Taking the snow depth value of 84.69 cm reckoned from hourly accumulated snowfall in Jiagedaqi as the reference snow depth, the results of the estimated snow depth are relatively consistent and well-founded. With the introduction of the forest phase, the average snow depth values estimated in the forest area increase by 5.98 cm, which reduces the underestimation of the snow depth in forest areas.

Protein conformation characterization via a silicon resonator-based optical sensor based on the combination of wavelength interrogation and dual polarization detection.

Protein conformational abnormality causes cell malfunction. Conformational change of amyloid protein causes neuron malfunction, which renders "protein conformational disease" Alzheimer's disease. Dual polarization interferometry enables to provide one-dimensional structure of a protein biolayer via deconvolution of interference patterns, which in turn is interpreted as the protein molecule conformation. However, it is still challenging to avoid interference patterns becoming faint and obscure sometimes. Resonance wavelength response to the biolayer structure can achieve a very low detection limit due to inherent high Q factor of an optical resonator. Here, we introduce the concept of combining dual polarization detection with wavelength interrogation via a simple and compact resonator-based optical biosensor. Biolayer were probed by the wave of dual polarization and its opto-geometrical parameters were resolved into resonance wavelength shift. Because protein molecule with distinct conformation produced a biolayer with unique thickness and mass density. Amyloid proteins in monomeric and dimeric morphology were respectively characterized. This concept enables protein conformation characterization in an easy and direct paradigm and provides a desirable sensing performance due to sensitive resonance response in the form of the sharp resonance profile occurring in a nonoverlapping spectrum.

Extraction and mapping of downpour impact and their Cumulonimbus origin, 20 May 2020, Vâlcea (Romania) via Sentinnel-1 SAR dual polarization

The aim of this work is to study the impact and characteristics of the meteorological phenomenon that occurred on May 20, 2020 in Vâlcea County, Romania. For this purpose, we used SAR radar images from the Sentinel-1 series at different dates, before, during and after the event. The methodology consists in exploiting and combining the two polarisations, VV and VH, of the recorded radar wave. The results obtained can be summarised as the extraction of areas completely covered by water and areas characterised by high roughness and very high humidity. The latter (roughness/humidity) can have two different origins. The first one corresponds to an area affected by downpours, giving a high roughness due to the interaction of water drops with the ground and also to the presence of hail, amplified by the wind factor. On the other hand, the second one coincides, quite simply, with the presence of a thundercloud, precisely a Cumulonimbus, which formed in that particular place as a result of the favourable geomorphological characteristics and meteorological conditions, giving a high humidity due to the high water content. We also determined the total impacted area of about 96.71 km2, whose 60.17 km2 of water covered area, which is 2.45% of the study area. The remaining 36.54 km2 (1.49%) represents the affected rough surface, located in the plain, or the humid surface corresponding to the area of the Cumulonimbus head covering the plain.

Establishment and verification of formulas of target tracking based on dual liquid crystal polarization gratings.

In this paper, the relationship between miss distance, target position, and rotation angle of dual liquid crystal polarization gratings (LCPGs) is proposed for the first time, a target tracking system based on the rotating dual LCPGs is established, and a closed-loop target tracking process based on the formula is described. We establish the optical structure of the dual LCPGs, and the simulation compares the difference between the altitude and azimuth angles of the target position from the formula and the ZEMAX simulation. In the simulation validation, we also compare and analyze the proposed formula with the formula for vertical incidence to illustrate the necessity to introduce miss distance. We assemble a target coarse tracking device and perform the tracking experiment using the proposed formula to test the coarse tracking accuracy of the system. The coarse tracking accuracy and the angle information we obtained from simulation and experiment meet our proposed technical specification of no more than 0.45mrad, showing that the proposed formula provides a good basis for stable target coarse tracking and is instructive for engineering applications.

REDUCING THE CROSS-POLARIZATION PATTERN IN A DUAL-POLARIZED ANTENNA USING SPIRAL AND SPLIT RING RESONATORS

This paper introduces the design of a new dual polarization rectangular microstrip patch antenna based on metamaterial structures at X-band. The work focuses on two distinct configurations of a microstrip patch antenna utilizing metamaterials. Pairs of spiral ring resonators are loaded into a rectangular patch antenna system in the first design. The second strategy involves inserting a split ring resonator at the end of microstrip feed lines. The utilization of metamaterial structures in the microstrip antenna system compensates for the patch antenna's asymmetric current distribution of the flow, resulting in symmetrical current distribution. The simulation results display an import cross-polarization cross-polarization discrimination (XPD) and good port decoupling. The antenna system has various characteristics, including a basic structure and metamaterial inclusions that take up a small amount of space, making the suggested metamaterial inclusions more beneficial for dual-linear polarized patch antenna construction. These prototypes are suitable to work for polarimetric radars.

Palaeomagnetic constraints on a Late Permian to Early Triassic final closure of thePalaeo‐AsianOcean

AbstractFinal closure of the Palaeo‐Asian Ocean signifies the ultimate amalgamation of the North China, Tarim, Mongolia, Songliao, Xilinhot and other Central Asian blocks, and therefore, is critical in reconstructing the configuration of the Pangea supercontinent during the late Palaeozoic to early Mesozoic. However, the final closure time remains contentious. Here, we present a systematic palaeomagnetic study on the Upper Permian sedimentary sequences of the Xilinhot Block, located to the north of the Solonker Suture Zone. Rock magnetic results indicate stable pseudo‐domain magnetite is the dominant magnetic carrier. The characteristic components isolated between ~350 and 590°C display the existence of dual polarities. Combined with previous results, the merged site‐mean directions yield a negative reversal test and inconclusive fold tests. By comparing with coeval and posterior data, and correlating with stitching plutons that intruded the sampling sections, we argue for a remagnetization origin for the newly obtained data, which is most likely acquired during the thermal event when the stitching granitic plutons intruded at 242.0 ± 3.7 Ma. Then we synthesized available palaeomagnetic data from the Central Asian Orogenic Belt and adjacent blocks, and propose a Late Permian to Early Triassic final closure of the Palaeo‐Asian Ocean. Our reconstruction of Pangea in the Early Triassic negates the existence of a cut‐through seaway between the Mongol‐Okhotsk and Palaeo‐Asian Oceans. The Mongol‐Okhotsk Ocean was an extension of Panthalassa, in trumpet‐shaped and faced to the east, rather than an individual oceanic basin separating Siberia from the Cinamuria Block.

Phase Noise Analysis of Resonator-Enhanced Electro-Optic Comb-Based Analog Coherent Receivers

We present an architecture for wavelength-division-multiplexed coherent data center links employing resonator-enhanced electro-optic frequency comb generators as both transmitter and local oscillator (LO) sources. We show that in each frequency comb, the phase noise in all comb lines is determined completely by the optical phase noise of the seed laser and the phase noise of the microwave oscillator. We propose an analog coherent receiver that performs carrier recovery on all wavelength channels using only two phase-locked loops. We use an independent cascade of phase shifters driven by marker tone detection in each channel for polarization recovery and compensation of a static optical phase shift. We study design examples for quadrature phase-shift keying and 16-ary quadrature amplitude modulation (16-QAM), determining requirements on the transmitter and LO seed laser linewidths and the LO frequency modulation (FM) response. We find that for a dual-polarization (DP) 16-QAM link with 17 wavelength channels, each operating at 56 GBaud, if the combined linewidth of the transmitter and LO seed lasers is 100 kHz, the LO seed laser requires an FM response that is flat from d.c. to several hundred MHz to maintain a phase-error penalty below 1 dB.

Dual-Band Spin-Decoupled Metasurface for Generating Multiple Coaxial OAM Beams

In this article, we propose a shared-aperture metasurface (MS) combining spin-decoupled strategy to generate four coaxially circularly polarized (CP) beams carrying orbital angular momentum (OAM) at Ku-band and Ka-band. First, the frequency selective surface (FSS) is adopted to suppress the mutual coupling between the Ku-band and the Ka-band. Next, at each band, the spin-decoupled meta-atom is designed to realize the independent control for dual circular polarizations. Subsequently, the designed MS illuminated by CP feed source would generate left-hand CP (LHCP) beam with OAM mode +1 and right-hand CP (RHCP) beam with OAM mode −1 at Ku-band; meanwhile, the LHCP beam with OAM mode +2 and the RHCP beam with OAM mode −2 are generated at Ka-band. Finally, the MS is designed, manufactured, and measured. Both simulated and measured near-field and far-field performance verify that the proposed MS can generate four independent CP OAM beams along the same spatial axis at dual bands. On the other hand, the experimental results and the corresponding theoretical analysis verify that the proposed MS illuminated by a linear-polarized (LP) feed source could also generate eight correlative LP OAM beams at dual bands.

MIMO antenna array with the capability of dual polarization reconfiguration for 5G mm-wave communication

This communication presents a polarization reconfigurable antenna array (PRAA) with Multi-input Multi-output (MIMO) formation for 5th generation (5G) millimeter wave (mm-Wave) communications. At first a single corner curtailed diagonal slotted cylindrical patch is printed on Roger RT Duriod 5880 and the overall size of the single antenna is 12 × 12 × 0.787 mm3. The circular polarization (CP) is realized by adding the diagonal slot in the circular patch. The antenna design is extended into two elements antenna array which occupies 20 × 20 × 0.787 mm3 footprint. The collection is formed using a T-shaped power divider/combiner. Pin-diodes are integrated with the patches to switch the polarization state between LP (Linear polarization) and CP radiation. The edge-to-edge distance between antenna elements is 6 mm. The design covers the 25.2–29.4 GHz band, and the maximum peak gain is 11.5 dBi. Moreover, a two-port (2 × 2) MIMO design is formed to increase the channel capacity. To isolate the ports, a sin-like slot is engraved in the ground, defected ground structure (DGS) technique of mutual coupling reduction; it can easily be implemented and increases the design efficiency. The port isolation is well above 30 dB for the entire operating band. Moreover, the Mean Effective Gain (MEG), Diversity Gain (DG), and Envelope Correlation Coefficient (ECC) are investigated, which are key performance metrics of MIMO. A prototype of the realized MIMO antenna system is fabricated, and the simulated outcomes carried out by Computer Simulation Technology (CST) tools are validated by experimental findings.

Coupling receiver–transmitter metasurface-based Fabry–Pérot resonant antenna with dual circular polarization

AbstractThis study presents a dual-circularly polarized (CP) Fabry–Pérot (FP) antenna, employing a novel receiver–transmitter (RT) metasurface (MS). The RT-MS unit cell consists of two identical neighboring substrates, with a three-layer metal coating printed on their surfaces. The bottom patch is adopted as a receiver to transfer electromagnetic waves to the top-corner cut patch, passing through the coupling cross-slot sandwiched in the middle. The RT-MS has high reflectivity to achieve a high gain. Through energy and a cross-slot, high aperture efficiency can be realized. A conventional corner cut patch can excite a CP mode of equal magnitude and a 90° phase difference. The RT-MS is arranged in 12 × 12 unit cells and used as a superstrate for a dual-CP antenna. Two orthogonally etched slots fed by two branch-matched orthogonally arranged feed lines are used as feeders to produce perpendicular linearly polarized waves. To enhance the bandwidth and improve the gain, double identical stack substrate patches are placed at the top side of the slot with no air gap, for a wide impedance band and high gain. Two wide CP bands, left-hand circular polarization and right-hand circular polarization, of 12.21–13.1 GHz (7.03%) and 12.35–13.1 GHz (5.89%), respectively, have maximum high gains of 16.5 and 15.97 dBic at 12.58 and 12.7 GHz, respectively, with a compact size of 2.6λ0 × 2.6λ0, suggesting better properties than recent antennas. The aperture efficiency can reach 63.2%. Thus, the RT-MS-based FP antenna is a good candidate for commercial and military communication systems.

Use of an L-band radiometer for proximal moisture measurement in road construction

The moisture content level during compaction plays a crucial role in the performance of road pavements. Current state-of-the-art methods involve manually taking small samples from a few isolated locations, making it difficult to monitor the spatial variation in moisture content along the entire construction corridor during compaction in an economically feasible manner. Therefore, finding an easy and effective method to measure soil moisture is a matter of importance. In agricultural applications, L-band passive microwave has proven to be the most accurate method for measuring soil moisture, with current satellites having a spatial resolution of approximately 40 km, which however is too coarse for road construction. Nevertheless, this technology can be deployed closer to the ground, to the point that a spatial resolution of less than 10 m is possible to achieve. Consequently, this study demonstrates the effectiveness of an L-band passive microwave radiometer for measuring soil moisture in the context of optimum compaction for road construction materials. An L-band radiometer called ELBARA-III was used to measure near-surface soil moisture in a 4.5 m × 7.5 m × 0.3 m test-bed having a sand subgrade and then an unbound granular material (UGM) sub base/base. The moisture content of the material was measured using traditional techniques such as taking thermogravimetric physical samples at targeted locations at 50 mm depth to validate the results. The results demonstrated that the L-band microwave radiometer can provide an accuracy of 5 % volumetric moisture content (VMC) or 3 % gravimetric moisture content (GMC) for sand subgrade and 2 % VMC or 1 % GMC for UGM sub base/base. An incidence angle of 0° using dual or single (horizontal or vertical) polarization was found to be the most effective configuration since it is less affected by surface roughness and is recommended for use in further field testing.

A metasurface enabled dual band antenna exhibiting dual polarizations with reduced beam squint and cross polarization

A compact, dual-band metasurface-based microstrip patch antenna with both linear and circular polarization (CP) for multiband communication is reported in this work. The ingredients in the antenna design consist of a combination of metasurface and metamaterial inspired structures that are demonstrated as an effective technique to correct the beam squint problem and reduce the cross-polarized radiation, usually experienced by thick substrate-based broadband CP antennas. A fractal boundary metasurface is introduced to achieve CP over a small frequency band. Eight Electric-LC resonators are symmetrically placed in the same plane of the radiating patch to widen the CP bandwidth, correct the beam squint, reduce the cross-polarized radiation, and realize a subwavelength resonance of λ0/5.15 order. The measured impedance bandwidths (|S11| < −10 dB) of the proposed antenna are 7.8% (3.7–4.0 GHz) and 27.58% (5.05–6.65 GHz) in the lower and upper-frequency band, respectively. The measured 3-dB axial ratio bandwidth (ARBW) is 24.8% (5070–6510 MHz) at 5.8 GHz. The fabricated prototype has an overall size of 55 × 55 × 4.08 mm (0.696λ0 × 0.696λ0 × 0.051λ0 at 3.8 GHz or 1.063λ0 × 1.063λ0 × 0.078λ0 at 5.8 GHz) with a realized peak gain of 4 dBi in the lower band and 7.1 dBic in the upper band. The measured results are consistent with the simulation results.

Multifocal Plane Display Based on Dual Polarity Stereoscopic Metasurface

AbstractStereoscopic 3D display devices have been developed toward integration and compactness. Metasurfaces have immeasurable advantages in the field of 3D display due to their tiny structures and flexible design capabilities. Here, a 3D multifocal display method based on stereoscopic metasurface (SMS) is proposed and demonstrated. Based on Dammann optimization method and Fourier expansion with zone plate to generate phase profile, such SMS can reorganize different planar images projected from Digital Mirror Device to form 3D images with correct depth clues. Thanks to the large Numerical Aperture of nano‐devices, total 20 multi‐focal planes can be independently used for display by considering dual polarization multiplexing. The experimental effects for stereoscopic arrangement of 3D number, letters, and several 3D images are demonstrated. Such compact‐scale SMSs have great potential to the applications of augmented/virtual reality devices, stereoscopic optical engraving, 3D optical manipulation, etc.