VIRAC Maser Data Processing Suite

Modern scientific research particularly radio astronomi- cal spectroscopic observations cannot be imagined without appropriate software suite. That is necessary because of two reasons 1) data are in digital form and 2) data processing is a complex multi-step process. In this paper created in VIRAC data processing suite for a single radio telescope, space maser observations are presented. Software Defined Radio (SDR) backend data processing is described. Implementation of the frequency switching algorithm, acquisition of observation data and their format for storing are discussed. Multiple ways to display the observation results are highlighted.

CIDF-WSN: A Collaborative Interest and Data Forwarding Strategy for Named Data Wireless Sensor Networks

Recent years have witnessed the huge popularity of Information-Centric Networking (ICN) and its realization as Named Data Networking (NDN) in the context of wireless sensor networks (WSNs). The participating nodes in WSNs are usually equipped with a single radio interface. The existing solutions lack in providing the efficient next forwarder selection in NDN-based single radio WSNs. In this work, we propose a collaborative Interest and Data Forwarding (CIDF-WSN) Strategy for Named Data Wireless Sensor Networks. CIDF-WSN develop a Neighbor Information Base (NFIB) which enables the node to select the optimal next-hop relay in Interest packet forwarding. An efficient Interest packet processing mechanism assisted by the Interest Cache Table (ICT) is provided to avoid Interest packets loss and frequent re-transmissions. In addition, CIDF-WSN also provides a robust Data packet transfer mechanism accompanied by the Temp Cache Table (TCT) to avoid Data packet losses and to ensure well-timed content delivery. Simulation results reveal that CIDF-WSN outperforms the recently published works in terms of Interest satisfaction rate, total energy consumption, Data retrieval delays, and communication overhead.

A Survey for Recent Techniques and Algorithms of Geolocation and Target Tracking in Wireless and Satellite Systems

A single Radio-Frequency Interference (RFI) is a disturbance source of modern wireless systems depending on Global Navigation Satellite Systems (GNSS) and Satellite Communication (SatCom). In particular, significant applications such as aeronautics and satellite communication can be severely affected by intentional and unintentional interference, which are unmitigated. The matter requires finding a radical and effective solution to overcome this problem. The methods used for overcoming the RFI include interference detection, interference classification, interference geolocation, tracking and interference mitigation. RFI source geolocation and tracking methodology gained universal attention from numerous researchers, specialists, and scientists. In the last decade, various conventional techniques and algorithms have been adopted in geolocation and target tracking in civil and military operations. Previous conventional techniques did not address the challenges and demand for novel algorithms. Hence there is a necessity for focussing on the issues associated with this. This survey introduces a review of various conventional geolocation techniques, current orientations, and state-of-the-art techniques and highlights some approaches and algorithms employed in wireless and satellite systems for geolocation and target tracking that may be extremely beneficial. In addition, a comparison between different conventional geolocation techniques has been revealed, and the comparisons between various approaches and algorithms of geolocation and target tracking have been addressed, including H∞ and Kalman Filtering versions that have been implemented and investigated by authors.

PENENTUAN WAKTU DAN METODE IMPLEMENTASI VOLTE PADA JARINGAN LTE (STUDI KASUS DI TELKOMSEL)

Teknologi 4G LTE diimplementasikan untuk meningkatkan kualitas dan speed layanan data, image perusahaan, dan interoperability dengan operator lain. Penelitian ini menganalisis VoLTE sebagai alternatif layanan voice di atas jaringan LTE dengan keterbatasan bandwidth frekuensi, tetapi kontribusi layanan voice yang masih tinggi pada studi kasus di Telkomsel. Penggunaan VoLTE merupakan tahapan selanjutnya setelah voice CS fallback. Tujuan dari penelitian ini adalah membangun sebuah model untuk menilai kelayakan implementasi VoLTE dengan berbagai skenario waktu dan metode teknologi dalam rangka menurunkan nilai risiko dari implementasi LTE, sehingga dapat menentukan waktu dan metode yang tepat bagi implementasi fitur layanan VoLTE pada jaringan LTE dengan dua cara yaitu sistem SRVCC (Single Radio Voice Call Continuity) atau langsung pada sistem PS handover. Metoda penelitian yang digunakan adalah komplementer atau triangulation dengan ilmiah dan alamiah, dengan menggunakan statistik regresi, variabel acak berlainan, perhitungan bandwidth, dan nilai bisnis. Disamping itu untuk menghitung nilai risiko dari probabilistik ketidakpastian, maka digunakan analisis sensitivitas dan analisis risiko melalui simulasi Monte Carlo. Hasil yang diharapkan adalah optimalisasi dan efisiensi penggunaan bandwidth serta pembuktian hipotesis tentang studi kelayakan proyek implementasi layanan VoLTE.

Glittery

During the commercial broadcasting boom of the 1920s, mica became an essential component of various radio parts, especially the audion vacuum tube, which became central to signal amplification during this period. As uses multiplied and factories produced greater quantities of sound-reproduction machines, the demand for mica exploded. This chapter traces a history of mica through the interwar years, arguing that the newfound necessity of this mineral pushed radio manufacturing into an existing—and vexed—infrastructure held together through exploitative labor regimes, environmental degradation, and the tense politics of empire during this period. It uncovers the surprisingly far-reaching political and social contexts involved in the production of a single radio component. The point of departure is RCA’s effort to find alternative sources of mica, which was primarily controlled by UK interests that, in turn, controlled key mica mines in India. These mines relied on female and child workers, deemed by many observers as the most efficient at splitting the extracted mineral into fine sheets. Such considerations drew RCA into direct negotiations with the US Bureau of Mines, the US Army, and mica mines in Appalachia and New Hampshire, thereby tethering them to hundreds of women and children in various parts of the world whose labor they deemed essential to their enterprise.

The Analysis of Experimental Deployment of IGLUNA 2019 Trans-Ice Longwave System

An experimental longwave system operating in the broadcasting spectrum with horizontal magnetic loop transmitting antennas is presented as an element of simulated lunar astronaut mission of the IGLUNA program of Swiss Space Center (ESA_Lab demonstrator) in June 2019 on the Klein Matterhorn glacier in Switzerland. The parameters of the antennas, the environment, the transmitter design, and propagation tests are presented. The best-suited propagation model is developed. As the system, using low powers, provided coverage of maximal distance of 2077.06 km, a single radio station of this type would cover about 36% of the Moon’s surface and allow in situ ground-penetrating research.

LeMMINGs – II. The e-MERLIN legacy survey of nearby galaxies. The deepest radio view of the Palomar sample on parsec scale

ABSTRACT We present the second data release of high-resolution (≤0.2 arcsec) 1.5-GHz radio images of 177 nearby galaxies from the Palomar sample, observed with the e-MERLIN array, as part of the Legacy e-MERLIN Multi-band Imaging of Nearby Galaxies Sample (LeMMINGs) survey. Together with the 103 targets of the first LeMMINGs data release, this represents a complete sample of 280 local active (LINER and Seyfert) and inactive galaxies (H ii galaxies and absorption line galaxies, ALG). This large program is the deepest radio survey of the local Universe, ≳1017.6 W Hz−1, regardless of the host and nuclear type: we detect radio emission ≳0.25 mJy beam−1 for 125/280 galaxies (44.6 per cent) with sizes of typically ≲100 pc. Of those 125, 106 targets show a core which coincides within 1.2 arcsec with the optical nucleus. Although we observed mostly cores, around one third of the detected galaxies features jetted morphologies. The detected radio core luminosities of the sample range between ∼1034 and 1040 erg s−1. LINERs and Seyferts are the most luminous sources, whereas H ii galaxies are the least. LINERs show FR I-like core-brightened radio structures while Seyferts reveal the highest fraction of symmetric morphologies. The majority of H ii galaxies have single radio core or complex extended structures, which probably conceal a nuclear starburst and/or a weak active nucleus (seven of them show clear jets). ALGs, which are typically found in evolved ellipticals, although the least numerous, exhibit on average the most luminous radio structures, similar to LINERs.