Multi Band Research Articles

Influence of Multiband Technique on Temporal Diffusion Spectroscopy and Its Diagnostic Value in Breast Tumors.

Temporal diffusion spectroscopy (TDS) is a noninvasive diffusion imaging technique used to characterizing cellular microstructures. The influence of multiband (MB) on TDS, particularly in breast tumor imaging remain unknown. To investigate the influence of MB on TDS in terms of scanning time, image quality, and quantitative parameters and to assess the diagnostic value of TDS with MB in breast tumors. Prospective. Seventy-one women with 71 confirmed lesions. 3.0 T; oscillating gradient spin-echo (OGSE), OGSE with MB, and pulsed gradient spin-echo, and routine magnetic resonance imaging squences. TDS with MB was used to assess diagnostic efficacy in differentiating benign and malignant tumors. A comparison of scanning time and image quality was performed in 17 patients. Imaging parameters were analyzed using limited spectrally edited diffusion (IMPULSED) and apparent diffusion coefficient (ADC) values were compared between MB and non-MB protocols. The cell diameter from TDS was compared with histopathological measurements in 21 patients. Bland-Altman plot, paired t test, Mann-Whitney U test, kappa test, DeLong's test, intraclass correlation coefficient agreement, receiver operating characteristic curve, area under the curve (AUC), and simple linear regression, with statistical significance set at P < 0.05. The TDS with MB protocol had a shorter average scanning time than that without MB protocol (7 minutes 22 seconds vs. 12 minutes 28 seconds); image quality was improved by reducing image artifacts. Most IMPULSED parameters and ADC values did not significantly differ between the MB and non-MB protocols (P = 0.23, P = 0.17). The IMPULSED parameters of cellularity and intracellular volume fraction achieved the highest AUC values for distinguishing breast tumors (0.865 and 0.821, respectively), surpassing the diagnostic efficiency of conventional ADC-1000 (0.776). The correlation between IMPULSED parameters and microscopic cell size was strong (r = 0.842). The MB technique improved the TDS protocol's efficiency and reduced the image artifacts. TDS parameters correlated with pathological findings and showed good performance in differentiating benign from malignant breast tumors. We explored the impact of simultaneous multislice acquisition technology on temporal diffusion spectroscopy (TDS) and whether combining this method could help distinguish benign from malignant breast tumors. Our findings showed that simultaneous multislice acquisition technology shortened the scanning time and improved image quality by reducing motion-related issues. Additionally, measurements of cell size using simultaneous multislice acquisition technology matched well with results from pathology tests. Overall, our study suggests that simultaneous multislice acquisition enhanced TDS could make breast cancer diagnosis more accurate and efficient, offering good advantages compared to conventional imaging methods. 2 TECHNICAL EFFICACY: Stage 2.

Simultaneous multislice diffusion imaging using navigator-free multishot spiral acquisitions.

This work aims to raise a novel design for navigator-free multiband (MB) multishot uniform-density spiral (UDS) acquisition and reconstruction, and to demonstrate its utility for high-efficiency, high-resolution diffusion imaging. Our design focuses on the acquisition and reconstruction of navigator-free MB multishot UDS diffusion imaging. For acquisition, radiofrequency-pulse encoding was used to achieve controlled aliasing in parallel imaging in MB imaging. For reconstruction, a new algorithm named slice-projection onto convex sets-enhanced inherent correction of phase errors (slice-POCS-ICE) was proposed to simultaneously estimate diffusion-weighted images and intershot phase variations for each slice. The efficacy of the proposed methods was evaluated in both numerical simulation and in vivo experiments. In both numerical simulation and in vivo experiments, slice-POCS-ICE estimated phase variations more precisely and provided results with better image quality than other methods. The intershot phase variations and MB slice aliasing artifacts were simultaneously resolved using the proposed slice-POCS-ICE algorithm. The proposed navigator-free MB multishot UDS acquisition and reconstruction method is an effective solution for high-efficiency, high-resolution diffusion imaging.

Digital Twin-Assisted Lightpath Provisioning and Nonlinear Mitigation in C+L+S Multiband Optical Networks.

Multiband (MB) optical transmission targets increasing the capacity of operators' optical transport networks. However, nonlinear impairments (NLI) affect each optical channel in the C+L+S bands differently, and, therefore, the routing and spectrum assignment (RSA) problem needs to be complemented with fast and accurate tools to consider the quality of transmission (QoT) within the provisioning process. This paper proposes a digital twin-assisted approach for lightpath provisioning to provide a complete solution for the RSA problem that ensures the required QoT in MB optical networks. The OCATA time domain digital twin is proposed, not only to estimate the QoT of a selected path but also to support the QoT-based channel assignment process. OCATA is based on a Deep Neural Network (DNN) to model the propagation of the optical signal. However, because of the different impacts of nonlinear noise on each channel and the large number of channels that need to be considered in C+L+S MB scenarios, OCATA needs to be adapted to make it scalable, while keeping its high accuracy and fast QoT estimation characteristics. In consequence, a complete methodology is proposed in this work that limits the number of channels being modeled to just a few. Moreover, OCATA-MB helps to mitigate NLI noise by programming the receiver at the provisioning time and thus with very little complexity compared to its equivalent implemented during the operation. NLI noise mitigation can be applied in the case when a lightpath cannot be provisioned because none of the available channels can provide the required QoT, making it an advantageous tool for reducing connection blocking. Exhaustive simulation results demonstrate the remarkable accuracy of OCATA-MB in estimating the QoT for any channel. Interestingly, by utilizing the proposed OCATA-MB-assisted lightpath provisioning approach, a reduction of the blocking ratio exceeding 50% when compared to traditional approaches is shown when NLI noise mitigation is not applied. If NLI mitigation is implemented, an additional over 50% blocking reduction is achieved.

Acceleration of Simultaneous Multislice Magnetic Resonance Fingerprinting With Spatiotemporal Convolutional Neural Network.

Magnetic Resonance Fingerprinting (MRF) can be accelerated with simultaneous multislice (SMS) imaging for joint T1 and T2 quantification. However, the high inter-slice and in-plane acceleration in SMS-MRF causes severe aliasing artifacts, limiting the multiband (MB) factors to typically 2 or 3. Deep learning has demonstrated superior performance compared to the conventional dictionary matching approach for single-slice MRF, but its effectiveness in SMS-MRF remains unexplored. In this paper, we introduced a new deep learning approach with decoupled spatiotemporal feature learning for SMS-MRF to achieve high MB factors for accurate and volumetric T1 and T2 quantification in neuroimaging. The proposed method leverages information from both spatial and temporal domains to mitigate the significant aliasing in SMS-MRF. Neural networks, trained using either acquired SMS-MRF data or simulated data generated from single-slice MRF acquisitions, were evaluated. The performance was further compared with both dictionary matching and a deep learning approach based on residual channel attention U-Net. Experimental results demonstrated that the proposed method, trained with acquired SMS-MRF data, achieves the best performance in brain T1 and T2 quantification, outperforming dictionary matching and residual channel attention U-Net. With a MB factor of 4, rapid T1 and T2 mapping was achieved with 1.5 s per slice for quantitative brain imaging.

Typical battlefield infrared background detection method based on multi band fusion

Intelligent battlefield environment recognition is crucial for active camouflage technology. Enhancing detection capabilities for various environments is essential for target survival. Traditional systems, relying on single visible light or infrared bands, face challenges like low detection performance and limited information use due to lighting conditions, making them inadequate for all-weather detection. This study presents a multi-modal feature fusion network model using a typical background database. It employs a coordinated attention mechanism for spatial information and optimizes dense and dual-path networks to improve the fusion of optical and infrared images. The model achieves 97.57% accuracy, 4.16% higher than the best single-modal results. The attention mechanism boosts accuracy by 2.68%. Thus, the model effectively integrates optical and infrared data, showing strong performance in classifying and detecting typical battlefield backgrounds.

Spatial Resolution and Noise impact on Multi Band Hyperspectral Image Processing

Spatial Resolution and Noise impact on Multi Band Hyperspectral Image Processing

Design and simulation of variable LC tank based on MEMS technology for multi band applications

Design and simulation of variable LC tank based on MEMS technology for multi band applications

Investigations on Penta Band High Isolation MIMO Antenna for 5G NR Bands and HIPERLAN Applications Using TCMA

The present article proposes a penta band Multiple Input Multiple Output (MIMO) antenna for 5G New Radio (NR) bands and HIPERLAN applications using Characteristic Mode Analysis (CMA). The design is obtained and optimised in step-by-step procedure using novel CMA approach and by perturbing the conventional rectangular structure with slots on the patch (left and right sides) and the ground plane (wide slot + narrow slots) for enhancing the isolation at multi bands. The MIMO configuration has a total dimension of 0.58 l0 × 0.35 l0 × 0.01 l0 mm3 with an optimum element separation of 0.05 l0 (l0 is the lowest frequency operating wavelength). Multiband resonance is produced at 2.2, 4.2, 7.2, 16, 17.5 GHz. The radiating elements can excite various characteristic modes that support wider bandwidth. The -10 dB impedance bandwidth at working region are 0.2, 0.2, 0.38, 3.6, 2 GHz respectively. The suggested design yields a gain of 2.1, 5.7, 3.5, 3.5, 5.2 dBi and consistent radiation patterns at the working frequencies. The analysis of the diversity performance considers the Diversity Gain (DG) and Envelope Correlation Coefficient (ECC), whose values are near 9.9 dB and 0, respectively. Additionally, the assessed parameters are the CCL and TARC. The structure prototype has been developed, and the observed findings are highly coherent with the simulated results, making it appropriate for use in 5G NR bands, HIPERLAN, and IoT applications.

Synthesis and characterization of cerium doped NiZn nano ferrites as substrate material for multi band MIMO antenna.

In addressing issues related to electromagnetic interference, the demand for ferrite materials with exceptional magnetic and dielectric properties has escalated recently. In this research, sol-gel auto combustion technique prepared Nickel zinc ferrites substituted with cerium, denoted as Ni0.5Zn0.5Ce0.02Fe1.98O4.X-ray diffraction (XRD), Vibrating Sample Magnetometer (VSM), and Field Emissions Scanning Electron Microscope (FESEM) were used to investigate the structure, magnetic properties, and morphology of Cerium doped NiZn Nano ferrites, respectively. The magnetic and dielectric properties of the sample was examined within a frequency range of 2.5-5.5 GHz. Sample exhibits low permittivity (2.2), high permeability (1.4), low dielectric (0.35) and magnetic loss tangent (-0.5) and highest saturation magnetization measuring 30.28 emu/g. A Novel Double-band, 4x4 MIMO window grill-modeled antennas operating on 3.5 GHz and 4.8 GHz frequency bands for 5G smartphones is designed using the CST microwave studio suite. The performance of window grilled 4x4 MIMO antenna model with Cerium doped NiZn nano ferrites as substrate, is investigated and found the return loss of -35 and -32 dB, with the bandwidth of 200MHz, gain (1.89 & 4.38dBi), envelope correlation coefficient (0.00185), channel capacity loss (0.2bps/Hz), and interterminal isolation of (22& 19dB).The results show that the antenna size is reduced with improved bandwidth, higher isolation and better diversity gain performance using Cerium doped NiZn nano ferrite substrate compared to conventional dielectric substrates.

Research on anti-interference performance of 5G multi band communication antenna supported by NFC technology

Research on anti-interference performance of 5G multi band communication antenna supported by NFC technology

Advanced optical transceiver and switching solutions for next-generation optical networks

Innovative transceiver and switching approaches should be explored with special focus on flexibility, energy efficiency, sustainability, and interoperability to be adopted on next-generation 6G optical networks driven by the diverse landscape of emerging applications and services and increasing traffic demand. In this regard, multiband (MB) and spatial division multiplexing (SDM) technologies arise as promising technologies for providing suitable network capacity scaling while fulfilling the stringent requirements of the incoming 6G era. In this paper, innovative MB over SDM (MBoSDM) switching node and sliceable bandwidth/bit rate variable transceiver (S-BVT) architectures with enhanced capabilities and features are proposed and experimentally validated. Different network scenarios have been identified and assessed, enabling up to 180.9 Gb/s S+C+L transmission in back-to-back (B2B) configuration. A MBoSDM scenario including both transceiver and switching solutions is demonstrated, including a 19-core multi-core fiber (MCF) of 25.4 km. Thanks to the transceiver modular and scalable approach, higher capacities can be envisioned by enabling multiple slices working in the different bands beyond the C-band. A power efficiency analysis of the proposed transceiver is also presented, including a pathway towards the integration with a software defined networking (SDN) control plane assisted by energy-aware artificial intelligence (AI)/machine learning (ML) trained models.

Tunable metamaterial absorption device based on Fabry–Perot resonance as temperature and refractive index sensing

This work presents a temperature-sensitive multi-band grating metamaterial absorption device (MAD) composed of gold, Dirac semimetal, and vanadium dioxide. And optimized the parameters using Particle Swarm Optimization (PSO) algorithm. The MAD design is simple, using a grating structure that is easy to process. It utilizes the principle of Fabry–Perot resonance to achieve multi band absorption while considering processability. Due to the introduction of VO2, the MAD has temperature sensing performance and PSO algorithm is introduced for optimization. The MAD achieved six perfect absorption peaks M1−M7. Additionally, the diffraction effect of the grating structure excites a seventh absorption peak. The bands of absorption peaks M1−M6 are 3.854 THz, 6.052 THz, 8.082 THz, 9.874 THz, 10.91 THz, 15.04 THz and 13.25 THz, respectively and the absorption rate are 0.9558, 0.9895, 0.9833, 0.9939, 0.9739, 0.9986, and 0.7906. The highest Q factor in the absorption mode of this MAD reaches 331, and the highest refractive index sensitivity reaches 7640 GHz/RIU. By studying the magnetic field distribution, we have provided an explanation for the physical mechanism of the MAD, and the MAD has demonstrated excellent tunability, thermal sensing performance, and refractive index sensing performance, making it promising for applications in various fields such as biomedical research.

Impact of the reconfigurable optical add-drop multiplexer architecture on the design of multi-band C+L+S optical networks

The main advantage of multi-band (MB) networks is to provide more capacity than C-band networks by using other unused bands like the L- and S-bands and, in this way, postpone the announced optical network capacity crunch. However, MB nodes have a more complex structure than C-band nodes, impacting their cost and enhancing their induced physical layer impairments (PLIs). The main goal of this paper is to analyze the impact of several MB node architectures (namely baseline, common-band and compact MB node architectures) on the total network capacity and total network cost-per-bit, using a routing, modulation format, and spectrum assignment (RMSA) network planning tool based on a Monte–Carlo simulation that also incorporates the impact of network PLIs. When the PLIs are neglected, the common-band architecture presents the lowest cost-per-bit compared to the remaining MB architectures, since only lower cost C-band components are used. However, with the PLIs impact, the common-band architecture leads to the lowest total network capacity and highest cost-per-bit due to additional noise coming from all-optical wavelength converters. In particular, the common-band total network capacity is less than half the baseline and compact total network capacities for a blocking probability of 1%, considering the best channel launch power. Also, the common-band cost-per-bit is almost twice the baseline and compact cost-per-bit due to the PLIs-induced degradation.

High directivity microstrip patch antenna design using binary ebola search optimization for radio frequency identification application

Microstrip patch antenna has gained significant popularity in wireless communication field, because of its compact size, less profile, and ease of installation. It is widely used in various applications such as Radio-Frequency Identification (RFID) systems, where dependable and long-range communication is made possible by the great directivity and efficiency. In this manuscript, a High Directivity Microstrip Patch Antenna design using Binary Ebola Search Optimization for Radio Frequency Identification Application (MPA-RFID-BESO) is proposed.The design of microstrip patch antennas is the difficulty in achieving high directivity while maintaining compact size and low profile. This research explains design and application-specific optimisation of the Microstrip Patch Antenna (MPA) of biomedical utilizing Binary Ebola Search optimization (BESO) algorithm. Microstrip patch antenna is designed to function in double and multi band applications due to its low cost, light weight, and ease of installation. MPA is made with flawed ground construction to lessen cross-polarized radiation emitted by microstrip patches and to achieve the necessary radiation parameters. Here, the cost of the materials is reduced by using a liquid crystal polymer substrate, and aerial performance is enhanced by using the appropriate geometrical parameters. The small design of the BESO optimised improves the performance of antenna as 50 mm×50 mm compact size. The MATLAB program uses high frequency to do the simulation method. The proposed antenna design is a preferable option for applications involving Radio Frequency Identification (RFID). The performance metrics, such as radiation pattern, constant gain, directivity, bandwidth, and antenna efficiency and return loss are measured and compared to the existing techniques. The proposed MPA-BA-BESO design provides 10.51%, 12.85% and 16.04% higher bandwidth and 23.63%, 47.86% and 32.06% higher gain compared with existing designs, like Designing MPA utilizing Moth–Flame optimization approach (MPA-UWB-MFOA), Predicting Rectangular Patch Microstrip Antenna Dimension utilizing Machine Learning (MPA-ANN), Dual Band Antenna Design and Prediction of Resonance Frequency Utilizing Machine Learning Algorithms (DBAD-RF-CNN) respectively. The proposed technology serve as a better design alternative for microstrip patch antennas in communication systems to address biological applications.

A SIMPLE STRUCTURED MULTIBAND TERAHERTZ METAMATERIAL ABSORBER WITH A HIGH Q FACTOR

A terahertz Eight-/Nine-/Twelve-/Fourteen-/Sixteen-Band Metamaterial Absorber (MMA) for sensing applications is built and simulated. The substrate is sandwiched between the bottom ground plane and the top patch structure of this primitive MMA. The top patch is made up of two concentric circular ring resonators. This structure generates a multiple number of multi bands without utilising stacked layers, multiple resonators, or overlapping in a single unit cell by altering the radius of the top patch structure within the shorter frequency range of 0.8 THz to 1.2 THz. The polarisation and angle insensitivity properties are investigated by shifting the angle values from 0 to 90 degrees. To learn about the inside mechanism of the planned structure, the magnetic field distribution, electric field distribution and surface current distribution plots are explained. For the sixteen-band MMA, the Q-Factor and full width half maximum are also determined. This proposed MMA will be used in biosensing applications, sensors and wireless communications.

Accelerated IVIM-corrected DTI in acute hamstring injury: towards a clinically feasible acquisition time

BackgroundIntravoxel incoherent motion (IVIM)-corrected diffusion tensor imaging (DTI) potentially enhances return-to-play (RTP) prediction after hamstring injuries. However, the long scan times hamper clinical implementation. We assessed accelerated IVIM-corrected DTI approaches in acute hamstring injuries and explore the sensitivity of the perfusion fraction (f) to acute muscle damage.MethodsAthletes with acute hamstring injury received DTI scans of both thighs < 7 days after injury and at RTP. For a subset, DTI scans were repeated with multiband (MB) acceleration. Data from standard and MB-accelerated scans were fitted with standard and accelerated IVIM-corrected DTI approach using high b-values only. Segmentations of the injury and contralateral healthy muscles were contoured. The fitting methods as well as the standard and MB-accelerated scan were compared using linear regression analysis. For sensitivity to injury, Δ(injured minus healthy) DTI parameters between the methods and the differences between injured and healthy muscles were compared (Wilcoxon signed-rank test).ResultsThe baseline dataset consisted of 109 athletes (16 with MB acceleration); 64 of them received an RTP scan (8 with MB acceleration). Linear regression of the standard and high-b DTI fitting showed excellent agreement. With both fitting methods, standard and MB-accelerated scans were comparable. Δ(injured minus healthy) was similar between standard and accelerated methods. For all methods, all IVIM-DTI parameters except f were significantly different between injured and healthy muscles.ConclusionsHigh-b DTI fitting with MB acceleration reduced the scan time from 11:08 to 3:40 min:s while maintaining sensitivity to hamstring injuries; f was not different between healthy and injured muscles.Relevance statementThe accelerated IVIM-corrected DTI protocol, using fewer b-values and MB acceleration, reduced the scan time to under 4 min without affecting the sensitivity of the quantitative outcome parameters to hamstring injuries. This allows for routine clinical monitoring of hamstring injuries, which could directly benefit injury treatment and monitoring.Key points• Combining high-b DTI-fitting and multiband-acceleration dramatically reduced by two thirds the scan time.• The accelerated IVIM-corrected DTI approaches maintained the sensitivity to hamstring injuries.• The IVIM-derived perfusion fraction was not sensitive to hamstring injuries.Graphical

Power-aware high-capacity elastic optical networks

The power consumption of telecommunication equipment has been identified as a relevant contributor to global energy consumption. In fact, new-generation optical transponders employ power-intensive electronic application-specific integrated circuits (ASICs) for digital signal processing (DSP). DSP design has traditionally prioritized meeting transmission requirements over power consumption optimization. In general, the evolutions of transmission techniques and network design have always been mainly driven by traffic increase; in this context, in order to operate network resources more efficiently, margin reduction has been investigated in the past few years. Indeed, traditionally, high physical layer margins are used to ensure reliability over an extended period, resulting in overprovisioning the optical connections for both physical layer conditions and capacity. On the other hand, super-channels have emerged as a suitable solution for accommodating the continuous traffic growth. However, power consumption has not been deeply considered in the optimization of super-channel transmission. This paper first investigates the power efficiency of super-channels operated with designed and reduced margins. Low-margin operation is enabled by adapting sub-carrier spacing and filter bandwidth. Power-aware super-channel optimization is then experimentally demonstrated leveraging a 600 Gbit/s transponder in the SDN-controlled elastic optical network (EON). The results have identified a trade-off between power consumption and spectrum efficiency. Furthermore, the ongoing bandwidth demand has motivated the investigation of multi-band (MB) transmission for scaling the capacity of the existing infrastructures. However, novel networking devices (e.g., optical amplifiers operating beyond the C- and L-bands) will affect the overall power consumption. In this context, experimental power analysis of a thulium doped fiber amplifier (TDFA) is performed based on the traffic load and corresponding configuration. The results show that TDFA power consumption varies with configuration and increases with output power.

Amplifiers in Multi–Band Scenarios—Output Power Requirements, Control and Performance Characteristics

Amplifiers in Multi–Band Scenarios—Output Power Requirements, Control and Performance Characteristics

Multi-functional Multi-band Metasurface for Linear and Circular Polarization in Reflection Mode

A new metasurface design is presented in multi and broad frequency bands. Metasurface has been designed on Roger 5880 substrate with a thickness of 1.575 mm. The top of the designed metasurface consists of two diagonal mirror m-shaped unit cells. The background plane covers the whole metasurface. Numerical results demonstrate the metasurface's capability for both linear (12.48-13.62 GHz, 19.00-27.64 GHz, 39.45-41.72 GHz, 44.68-45.18 GHz, and 47.52-48.28 GHz) and circular (11.5-12.07 GHz, 30.01-37.77 GHz, 42.3-44.2 GHz, 45.45-47.1 GHz, 48.7-49.54 GHz) polarization conversion with over 90% efficiency. At the same time, the metasurface has good angular stability up 45^0.

Multi band square-shaped polarization-insensitive graphene-based perfect absorber

Multi band square-shaped polarization-insensitive graphene-based perfect absorber