Search Results (974)

As fifth-generation (5G) networks evolve toward open and software-based architectures, security verification of the NG Application Protocol (NGAP) between the radio access network and the 5G core has become increasingly important. This paper proposes a stateful security verification methodology that combines stateful fuzzing with specification-guided security verification. The methodology derives an Access and Mobility Management Function (AMF) state model, mutation types, and expected behaviors from Third Generation Partnership Project (3GPP) specifications. For each attack scenario, it establishes the required connection state through normal NGAP procedures, injects a mutated message, and compares the observed AMF responses and processing logs with the specification-defined expected behavior. We evaluated four open-source 5G core implementations using 324 attack scenarios per implementation, resulting in 1296 tests. Of these, 877 produced sufficient evidence to interpret the AMF processing outcome, yielding an interpretable outcome rate of 67.7%. The evaluation covered 27 of the 40 uplink NGAP message types and identified 32 specification violations, including 11 security vulnerabilities, none of which caused a core to crash. These results demonstrate the importance of jointly considering connection states and specification-defined behavior in NGAP security verification. Full article

Fast radio bursts (FRBs) are enigmatic millisecond-duration radio transients whose polarization properties offer crucial insights into their origins and environments. In particular, low-frequency depolarization—quantified by the parameter ${\sigma }_{\mathrm{RM}}$—probes the complex magneto-ionic medium surrounding the progenitor, and has been observed across a population of repeating FRBs. We present a systematic spectro-polarimetric analysis of repeating and non-repeating FRBs using observations from the Canadian Hydrogen Intensity Mapping Experiment (CHIME). For 28 repeating FRBs, we measure ${\sigma }_{\mathrm{RM}}$, expanding the known sample from 14 to 36 sources (an increase by a factor of 2.6). The kernel density estimate (KDE) of the repeating population peaks at $1.3\mathrm{rad}{\mathrm{m}}^{-2}$, with approximately 70% of the sources showing ${\sigma }_{\mathrm{RM}}\gtrsim 1\mathrm{rad}{\mathrm{m}}^{-2}$, implying that most reside in complex magneto-ionic environments. For 70 non-repeating FRBs, we investigate four spectro-polarimetric models; no source exhibits significant depolarization with ${\sigma }_{\mathrm{RM}}\gtrsim 5\mathrm{rad}{\mathrm{m}}^{-2}$. Roughly half of the non-repeaters are consistent with a constant linear polarization fraction across frequency. We caution, however, that these results may be affected by the limited frequency coverage of CHIME. Future ultra-wideband polarimetry, spanning widely separated frequencies, will overcome current observational biases, enable precise ${\sigma }_{\mathrm{RM}}$ measurements, and substantially deepen our understanding of FRB environments. Full article

Lightning discharges over the Tibetan Plateau are monitored by ground-based networks that locate radiation sources from their low-frequency radio emissions. This study uses the Qinghai Datong network in the northeastern Tibetan Plateau, which records the 50 kHz to 2.5 MHz band over a small area to locate lightning in three dimensions. In such networks, the accuracy of three-dimensional location depends critically on the consistency of the signals recorded across stations, which is progressively degraded by aging analog front-ends and by complex electromagnetic noise. To address this, we propose a phase-preserving denoising scheme, termed WZ, that suppresses both broadband and narrowband noise while keeping the relative timing between stations essentially unchanged, so that the arrival times used for location are preserved. The improvement is illustrated with both simulations and real data. In Monte Carlo simulations, WZ improves the signal-to-noise ratio by 10 dB and reduces the time-of-arrival error to 0.3 μs. Applied to two intracloud flashes of contrasting morphology, WZ recovers substantially more radiation sources and more continuous discharge channels than conventional filtering, at no cost to fit quality, allowing, for example, the downward development of the channel to be tracked quantitatively. The method requires no change to the existing hardware and can be applied to archived data, making it a practical way to improve both current and historical records from long-running low-frequency lightning networks. Full article

The transition from early non-standalone 5G deployments to 5G Standalone and, more recently, 5G-Advanced has turned mobile networks into flexible, programmable infrastructures capable of supporting private, industrial, and research-oriented deployments for the development of beyond-5G applications and architectures. Evaluating these networks’ capabilities, however, remains challenging because commercial platforms often provide limited access to internal interfaces, radio parameters, and network measurements. This paper presents an open-source private 5G SA testbed for beyond-5G application validations built using Open5GS, srsRAN, Ettus USRP N310 software-defined radio, programmable SIM cards, and commercial 5G customer-premise equipment. The platform is deployed in a semi-anechoic chamber. End-to-end operation is validated through subscriber registration, authentication, PDU session establishment, and external data connectivity. The performance of the implemented 5G network is evaluated using throughput, block error rate, modulation and coding scheme, and gNB trace logs. Unlike previous open-source 5G testbeds that primarily use RF waveguides, individual network components, or a limited set of radio configurations, the proposed platform combines COTS SIM-based UE operation with a controlled over-the-air evaluation of FDD/TDD and multiple antenna configurations and correlates application-level throughput with internal gNB radio metrics. For FDD downlink operation, the average throughput increased by approximately 74% from 1 × 1 to 2 × 2 and by a further 57% from 2 × 2 to 4 × 4, although the additional peak-throughput gain from 2 × 2 to 4 × 4 remained limited. The platform provides a reproducible environment for validating beyond-5G mechanisms, comparing network configurations, and studying the behavior of future open-source 5G SA systems under controlled conditions. Full article

This mini-review is intended to show how multimodal imaging could be developed from prototypes and proofs of concept by controlling the nanoscale for improved resolution of life science imaging for broad applications such as bioassays, early diagnoses and further applications. It intends to afford the presentation of multimodal approaches for imaging and bioimaging uses with potential applications to biological media. The application of multimodal nanoemitters provides enhanced bioimaging through the generation of various targeted and well-defined signals. Radionuclides and luminescent emitters were considered in the discussion for improved and enhanced signaling. In this manner, we intended to show the increase in the power of information by collecting varied optical signal–matter interactions. This could be important for Positron Emission Tomography and Computed Tomography (PET-CT), Fluorescence Tomography (FT), and other new modes of imaging contemplating the incorporation of nanotechnology. In the context of the design of new multimodal energy modes, key examples were shown from the literature, where the interactions of different energy modes could lead to enhanced and improved signaling. Electromagnetic fields and nanoplasmonics are involved in these different energy modes involving varied quantum particle interactions with modified properties. In this regard, multimodal imaging has experienced developments in nanoemitters and nanobiolabeling to track biomolecular events and targeted cells. A large quantity of research output actually focuses on nano- and quantum emissions. However, there are not as many studies dealing with enhanced emissions or laser emissions coupled with radionuclide emitters. A non-classical form of light emission, considering varied luminescent phenomena as well as further quantum signaling, showed interesting and high-impact perspectives when combined with nuclear emissions. This is the case for current trends focusing on innovative single-cell analysis. For example, the characterization and diagnosis of cells where the targeting of antibody–antigen interactions is required, providing light and energy from different sources to produce different details and imaging resolutions, has been noted. These are potential approaches that could be developed through various strategies targeting life science applications. In this regard, this article puts forward a discussion focused on nanotechnology contemplating radio-pharmacy and enhanced nanoemitters. Full article

High-frequency VLBI (Very Long Baseline Interferometry) observations impose stringent requirements on antenna pointing accuracy. This paper proposes a high-precision pointing implementation method that integrates a multi-error-source coupled model with hierarchical compensation. Taking an 18-m antenna as the object of study, the influence of gravity is quantified through structural-electromagnetic coupled simulation, establishing a unified model encompassing geometric, random, environmental, and dynamic errors. Using the 95% confidence bound (defined as 1.96σ for each error component) and the RSS (Root Sum of Squares) synthesis method, the budgeted system pointing error is estimated to be 8.64 arcseconds (at 40 GHz). An innovative three-level compensation system of “mechanical adjustment—model calibration—active suppression” is constructed, clarifying the mapping relationship between error sources and the TPOINT (Telescope POINT) model. To validate the proposed approach, actual radio source tracking experiments were conducted on the 18-m antenna. The experimental results demonstrate that after applying the three-level compensation strategy, the residual pointing error is reduced to approximately 7.9″ (RMS@95%), which agrees well with the theoretical budget of 8.64″. This method provides a systematic solution for the precision design and engineering implementation of high-frequency antennas, with the effectiveness confirmed through both theoretical budgeting and experimental validation. Full article

The fifth edition of the Roma-BZCAT catalog (5BZCAT) contains 227 blazars of the uncertain type (BZU), whose available data do not support an unambiguous assignment to the BL Lacertae object (BZB), flat-spectrum radio quasar (BZQ), or host-galaxy-dominated blazar-like source (BZG) categories. We construct a machine-readable value-added catalog for these sources using 1151 BZB, 1909 BZQ, and 274 BZG catalog entries as the supervised reference sample. The compact input set contains redshift, optical magnitude, radio, X-ray, and gamma-ray measurements; missingness indicators; and spectral slopes connecting the radio, optical, and X-ray bands. Redshift and its availability are explicitly treated as optical-spectroscopy-related label proxies. Cross-validation shows that the Light Gradient Boosting Machine (LightGBM) provides the most reliable probability scores among the tested models, although the stacking ensemble gives a slightly higher balanced accuracy. The final catalog reports LightGBM probabilities and contains 61 BZB-like, 120 BZQ-like, and 46 BZG-like sources; 17 are flagged for low probability separation. These probabilities quantify similarity to existing 5BZCAT labels conditional on catalog measurements, rather than an independent physical taxonomy. Full article

Active surface shape control is a key engineering technology enabling high-frequency operation and high-performance observations in modern large-aperture radio telescopes. By determining the achievable controllable accuracy of the primary reflector, its performance further constrains the aperture efficiency and long-term stability of telescope sensitivity. As millimeter- and submillimeter-wave astronomy advances toward higher operating frequencies and larger survey scales, key astrophysical questions increasingly demand the simultaneous achievement of high angular resolution, high surface-brightness sensitivity, and high imaging efficiency over wide fields of view. Limited by field-of-view coverage, sensitivity, or spatial-scale uniformity, traditional single-dish or interferometric array systems struggle to simultaneously satisfy these observational requirements. Consequently, large-aperture, wide-field millimeter/submillimeter single-dish telescopes are regarded as an important technological pathway for achieving multi-scale, high-fidelity observational capability. Their performance critically depends on effective control of primary reflector accuracy and system stability under multiple disturbance sources, such as gravity and thermal effects. From a system-level perspective, this paper provides an overview of the overall architecture of active surface control technologies for large-aperture millimeter- and submillimeter-wave single-dish radio telescopes. Focusing on three core components—surface measurement, actuator execution, and surface control strategies—it systematically reviews the underlying technical principles, representative engineering practices, technological evolution, and recent research progress. The characteristics of different technical approaches are summarized and analyzed, providing a reference for the design and further study of active surface control systems for large-aperture radio telescopes. Full article

Primordial black holes (PBHs) in the asteroid-mass range, with typical masses ${10}^{17}\mathrm{g}\lesssim M\lesssim {10}^{23}\mathrm{g}$, have drawn significant recent attention as viable dark matter candidates. The peak frequencies of photons emitted via Hawking radiation from asteroid-mass PBHs range from infrared to $\gamma$-ray bands. We calculate expected local transit rates for extended PBH mass distributions that could comprise all dark matter. We evaluate prospects for detecting Hawking-radiated photons from local PBH transits through the inner Solar System and from PBH explosions in the far outer edges of the Solar System. We consider several existing and proposed ground-based and space-based instruments sensitive to photons from the radio band to ultrahigh-energy $\gamma$-rays. We find that the proposed instruments, such as the All-sky Medium Energy Gamma-ray Observatory eXplorer (AMEGO-X) satellite, can reliably detect PBH transits within $\mathcal{O}\left(0.1\mathrm{AU}\right)$ of the Earth, while the High Altitude Water Cherenkov (HAWC) observatory and Large High Altitude Air Shower Observatory (LHAASO) are both sensitive to PBH explosions out to $\mathcal{O}\left(0.1\mathrm{pc}\right)$ and $\mathcal{O}\left(0.5\mathrm{pc}\right)$, respectively. We conclude by specifically considering potential companion electromagnetic signatures in the case of a PBH explosion about ${10}^3\mathrm{AU}$ from Earth, which has been suggested as a potential source for the ∼220 PeV ultrahigh-energy KM3-230213A neutrino event observed by the KM3NeT collaboration in 2023. Whereas we find that the recent KM3NeT event would not have yielded detectable electromagnetic signals—due to its location on the sky, proposed distance from Earth, and the offline status of the HAWC observatory at that time—we demonstrate that future PBH explosions at comparable distances could yield electromagnetic signals measurable from Earth, depending on the alignment of the PBH burst with detector fields of view. Full article

High-frequency very long baseline interferometry (VLBI) polarimetry probes synchrotron-emitting plasma closer to the central engines of radio-loud active galactic nuclei (AGNs), but observations above 43 GHz are technically demanding. We present 22-GHz European VLBI Network observations of the $z=4.31$ quasar J1510+5702 and J1606+3124, whose published spectroscopic redshift, $z=4.56$, is uncertain; a photometric estimate gives $z_{\mathrm{phot}}=0.9\pm 0.1$. For the published $z>4$ redshifts, 22 GHz corresponds to rest-frame frequencies above 118 GHz. Polarized emission is detected in J1510+5702, and a low-level polarized signal is recovered from the brightest feature of J1606+3124. Adopting $z=4.56$, that feature has a brightness temperature of $T_{\mathrm{b},\mathrm{VLBI}}=(7.4\pm 0.8)·{10}^{10}$ K, allowing a mildly Doppler-boosted interpretation, while the young compact-source scenario also remains viable. The core of J1510+5702 has $T_{\mathrm{b},\mathrm{VLBI}}=(1.08\pm 0.15)·{10}^{12}$ K, implying a Doppler factor of $\sim 22$ under the equipartition assumption. This component has a $\sim 3.5$% fractional polarization. These observations show that cm-wavelength VLBI can access rest-frame millimeter-band polarization in bright $z>4$ jets. Full article

(1) Background: The disaggregated and software-defined nature of fifth-generation (5G) core networks and the Open Radio Access Network (O-RAN) architecture increase the attack surface and produce large volumes of heterogeneous evidence that must be analyzed in real time to support incident reconstruction. Open-source 5G stacks (including Open5GS and srsRAN) have become reference platforms in the literature, yet recent research, such as the RANsacked study that reported 119 vulnerabilities and 97 unique CVEs across multiple LTE/5G implementations, have highlighted the pressing need for AI-based detection and forensic capabilities specific to these stacks. (2) Methods: We introduce an experimental framework consisting of a reproducible srsRAN+Open5GS testbed and an AI-driven forensic and detection pipeline. The pipeline receives control-plane (NAS, NGAP, F1AP) and Service-Based Interface (SBI) traffic, extracts protocol- and statistically grounded features and classifies traffic into seven attack types using a hybrid CNN–LSTM model. Integrity-protected and timeline-correlated forensic artifacts (PCAP, logs, memory dumps) assist in reconstructing an incident. (3) Results: The proposed hybrid model achieves a macro F1-score of 0.972 and an AUC-ROC of 0.995 (5-fold CV) and degrades gracefully under load. (4) Conclusions: We show that AI-based detection can be coupled with a scientifically sound evidence chain in open-source 5G stacks deployed as disaggregated mobile networks. Full article

The blazar PKS 0346-27 at redshift $z=0.991$ is among the most distant extragalactic sources detected in very high energy $\gamma$-rays. It underwent a major flare reaching TeV energies in November 2021. Recent modelling of its spectral energy distribution favoured a single-zone proton–synchrotron-dominated hadronic model with bulk Lorentz factor $\Gamma =10$ over a single-zone leptonic jet model with much higher $\Gamma$. Here we analyse archival radio data to give independent estimates of the jet bulk Lorentz factor. We present high-resolution radio imaging and brightness distribution modelling, as well as flare detection in long-term radio flux density monitoring data, and obtain $\Gamma \lesssim 10$ values. This lends support to the hadronic model proposed for the PKS 0346-27 jet. Our results highlight the importance of long-term, very long baseline interferometry and total flux density monitoring in studying blazar jets. Full article

Calendula officinalis L. (pot marigold) is a medicinal and edible plant used as a source of bioactive compounds with potential applications in functional foods. This review brings together current data on the phytochemical profile, biological activity, agronomic factors, and food applications of C. officinalis, based on 76 publications. More than 500 secondary metabolites have been reported in this species, including flavonoids, carotenoids, terpenoids, polysaccharides, coumarins, and essential-oil components. Reported levels depend strongly on cultivar, growing conditions, plant part, and analytical method. Total flavonoid content in dried flowers ranges from 0.21 to 0.68% across 20 European cultivars, with up to 1.7% in selected Estonian-grown cultivars such as ‘Radio’. Reported total carotenoid values cover almost two orders of magnitude (about 48 to 3510 mg/100 g of dried material), reflecting differences in plant part, colour variant, and method (spectrophotometric sum vs. HPLC). Dried flowers contain up to 62.33 g/100 g of total dietary fibre (mostly insoluble). The associated activities are antioxidant, anti-inflammatory, antimicrobial, regenerative, cytotoxic, and neuroprotective. Recent food-application studies show useful effects in yogurt (0.25 g lyophilized extract/100 g), wheat bread (10–15% of formulation water replaced with aqueous extract), and fresh pasta (5% flower powder substitution), with notable increases in antioxidant capacity and acceptable sensory scores. The number of full food-product trials is still small, and this review identifies the processing variables and the research gaps that determine whether C. officinalis can be used as a standard functional-food ingredient. Full article

Smart grids with renewable energy sources require communication platforms that can evaluate heterogeneous links before field deployment. This article presents a centralized software-defined radio (SDR)-based performance analytics platform for physical/MAC-layer assessment of RF900, G3-PLC, GPRS CS2–CS3, hybrid PLC–GPRS, and renewable-event communication profiles. The platform combines a controlled UPS SDR/USRP experimental-simulation reference with reproducible packet-level simulations using traffic generation, channel impairment abstractions, CRC-based integrity verification, and centralized metrics: latency, bit error rate (BER), packet error rate (PER), useful throughput, and offered channel load. The revised evaluation uses a 120 s window, 3444 packets per baseline scenario, and 30 independent random seeds. The RF900 AWGN baseline achieved $36.58\pm 0.01$ ms mean latency, $1.78\times {10}^{-4}$ BER, $0.175\pm 0.003$ PER, and 24.23 kbps useful throughput. Hybrid PLC–GPRS reduced PER to $0.025\pm 0.001$, while the renewable-event hybrid profile achieved $89.33\pm 0.13$ ms and $0.028\pm 0.001$ PER. This study provides a reproducible pre-deployment analytics framework, not full utility field validation or application-layer interoperability certification. Full article

Testing advanced driver assistance systems (ADAS) under rare or safety-critical conditions is impractical at full scale: track campaigns are expensive, time-intensive, and cannot easily reproduce low-probability events. Scaled cyber–physical testbeds offer a more accessible path by coupling miniature vehicle platforms with virtual simulation environments, but the field has no unified review that covers co-simulation architectures, indoor localization, and ground truth strategies in a single treatment. This paper addresses that gap with a PRISMA 2020-compliant systematic review of 92 primary sources selected from 984 records identified across IEEE Xplore and Scopus. Three topic areas are examined: real-time co-simulation architectures built on AirSim, CARLA, Gazebo, and LGSVL, compared for ROS 2 integration, synchronisation model, and edge hardware suitability; three indoor localization methods, namely AprilTag fiducial tracking, Visual Simultaneous Localization and Mapping (VSLAM), and Ultra-Wideband (UWB) radio positioning, evaluated against shared accuracy, latency, infrastructure, and robustness criteria; and existing ground truth strategies for indoor localization benchmarking. A consistent finding across the corpus is that no controlled cross-method localization comparison exists for scaled testbeds. To address this, we introduce the Programmable Ground Truth Reference System (PGTRS), which renders spatial references on a programmable LED floor panel at a pixel pitch of approximately 3.9 mm, targeting sub-centimetre ground truth accuracy without dedicated motion-capture infrastructure. The concept is demonstrated within a 1:14 scale Digital Driving Twin (DDT) testbed built at the University of Applied Sciences Wildau at a hardware cost of approximately €6576. Design guidelines and open research challenges are discussed. Full article