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New standards are emerging every few months as wireless bands and services are proliferating across the world. End users of mobile headsets, wireless speakers, appliances controlled by internet, and many other devices want as many as possible new services and manufacturers have a hard time to keep up. Therefore, wireless radio solutions which can cover more bands and standards are in high demand. Multi-band multi mode radios by stacking up of multiple modules can be a choice to cover more bands in one system at a higher cost and larger area. Newer multi-band multi-mode radios integrate multiple radios into one chip and by reducing the packaging cost, sharing the peripheral components, and lowering the size, cover larger frequency range at lower cost. Software defined radios (SDRs) and cognitive radios (CRs) can address the increasing demand of users to have seamless connection at low service cost and support wide range of applications [24]. Ultra-wideband (UWB) radios also cover a wide spectrum supporting universal applications in different countries. The WiMedia UWB radio technology requires the frequency synthesizers to cover the 3.1 GHz to 10.6 GHz spectrum. Different communication systems take advantage of millimeter-wave phased arrays such as 60 GHz short-range communication and point-to-point communication at the E-band (71-76 and 81-86 GHz) and the W-band (75-110 GHz). All the mentioned radios need carrier frequency generators which are able to cover all the frequency bands of interest which is several GHz. Also, these frequency generators must be able to generate quadrature local oscillator signal (LO).Quadrature signals are essential in modern transceivers which can be generated in different ways. Among different ways, quadrature oscillators show better performance. The LC-QOSCs show a superior phase noise performance with excellent quadrature accuracy. To practically use CMOS LC quadrature oscillators, the randomness of the quadrature phase of the QOSCs should be fixed. The random phase sequence in LC-QOSCs results in limited tuning range which might be even zero. The series coupled QOSCs proposed in here address the quadrature phase sequence ambiguity by guaranteeing oscillation in one mode. Furthermore we have proposed a novel idea where the S-QOSC quadrature mode can be selected, and since each mode has a different frequency, in this way a wider tuning range can be achieved from the QOSC which is essential in wide tuning range frequency synthesizers and is useful in multi-band radios, SDR, CR, and UWB radios.Replacing the crystal oscillators (XTALs) which are the main reference frequency generators in transceivers has a high priority to reduce the overall cost and power consumption of different wireless systems. CMOS frequency generators mostly cannot compete with the accuracy and phase noise performance of XTALs and even with the aid of calibration cannot achieve descent frequency stability due to temperature variation as they are very sensitive to temperature.The focus of this work is on wide tuning range oscillators applicable in broadband radios. This work presents a wide tuning range series coupled quadrature S-QOSCs which is able to oscillate in desired quadrature mode of oscillation and eliminate the randomness in the quadrature sequence. By selecting the mode, the proposed S-QOSC (Chapter 4) has a very wide tuning range which is the combination of tuning range of different modes. It has also been shown (Chapter 5) that the proposed S-QOSC can be designed to show two orders of magnitude less temperature sensitivity compared to other LC oscillators and can be implemented in a system to be calibrated to achieve the required frequency accuracy of various applications. In this work an LO-phase shifting approach based on ILO at frequency range of 71 to 86 GHz will be presented.

We present the status of the development of a Cherenkov telescope to be flown on an ultra-long-duration balloon flight, the Extreme Universe Space Observatory Super Pressure Balloon 2 (EUSO-SPB2). EUSO-SPB2 is an approved NASA balloon mission that is planned to fly in 2023 from Wanaka, New Zealand and is a precursor for future space-based missions to detect astrophysical neutrinos. The objectives of this mission are to classify known and unknown sources of background and make the first observation of cosmic rays via Cherenkov technique from suborbital altitude. We also intend to perform target of opportunity searches in response to international multi-messenger alerts and use the Earth-skimming technique to search for Very-High-Energy (VHE) tau neutrinos below the Earth’s limb (E > 10 PeV). The 0.785 m^2 Cherenkov telescope is equipped with a 512-pixel SiPM camera, covering 12.8° x 6.4° (Horizontal x Vertical) field of view, that utilizes novel stereo optical system. The camera signals are digitized with a 100 MS/s readout system. In this poster, we report the status of the telescope development and its integration, and discuss the recent field test results.

The field of UHECRs (Ultra-High energy cosmic Rays) and the understanding of particle acceleration in the cosmos, as a key ingredient to the behaviour of the most powerful sources in the universe, is of outmost importance for astroparticle physics as well as for fundamental physics and will improve our general understanding of the universe. The current main goals are to identify sources of UHECRs and their composition. For this, increased statistics is required. A space-based detector for UHECR research has the advantage of a very large exposure and a uniform coverage of the celestial sphere. The aim of the JEM-EUSO program [1] is to bring the study of UHECRs to space. The principle of observation is based on the detection of UV light emitted by isotropic fluorescence of atmospheric nitrogen excited by the Extensive Air Showers (EAS) in the Earth's atmosphere and forward-beamed Cherenkov radiation reflected from the Earth's surface or dense cloud tops. In addition to the prime objective of UHECR studies, JEM-EUSO will do several secondary studies due to the instruments' unique capacity of detecting very weak UV-signals with extreme time-resolution around 1 μs: meteors, Transient Luminous Events (TLE), bioluminescence, maps of human generated UV-light, searches for Strange Quark Matter (SQM) and high-energy neutrinos, and more. The JEM-EUSO program includes several missions from ground (EUSO-TA [2]), from stratospheric balloons (EUSO-Balloon [3], EUSO-SPB1 [4], EUSO-SPB2 [5]), and from space (TUS [6], Mini-EUSO [7]) employing fluorescence detectors to demonstrate the UHECR observation from space and prepare the large size missions K-EUSO [8] and POEMMA [9]. A review of the current status of the program, the key results obtained so far by the different projects, and the perspectives for the near future are presented., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

The TUS observatory was the first orbital detector aimed at the detection of ultra-high energy cosmic rays (UHECRs). It was launched on April 28, 2016, from the Vostochny cosmodrome in Russia and operated until December 2017. It collected ∼ 80, 000 events with a time resolution of 0.8 μs. A fundamental parameter to be determined for cosmic ray studies is the exposure of an experiment. This parameter is important to estimate the average expected event rate as a function of energy and to calculate the absolute flux in case of event detection. Here we present results of a study aimed to calculate the exposure that TUS accumulated during its mission. The role of clouds, detector dead time, artificial sources, storms, lightning discharges, airglow and moon phases is studied in detail. An exposure estimate with its geographical distribution is presented. We report on the applied technique and on the perspectives of this study in view of the future missions of the JEM-EUSO program., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

Mini-EUSO is a small orbital telescope with a field of view of 44◦ × 44◦, observing the night-time Earth mostly in 320-420 nm band. Its time resolution spanning from microseconds (triggered) to milliseconds (untriggered) and more than 300 × 300 km of the ground covered, already allowed it to register thousands of meteors. Such detections make the telescope a suitable tool in the search for hypothetical heavy compact objects, which would leave trails of light in the atmosphere due to their high density and speed. The most prominent example are the nuclearites – hypothetical lumps of strange quark matter that could be stabler and denser than the nuclear matter. In this paper, we show potential limits on the flux of nuclearites after collecting 42 hours of observations data., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

The Extreme Universe Space Observatory on a Super Pressure Balloon II (EUSO-SPB2) is a second generation stratospheric balloon instrument for the detection of Ultra High Energy Cosmic Rays (UHECRs, E > 1 EeV) via the fluorescence technique and of Very High Energy (VHE, E > 10 PeV) neutrinos via Cherenkov emission. EUSO-SPB2 is a pathfinder mission for instruments like the proposed Probe Of Extreme Multi-Messenger Astrophysics (POEMMA). The purpose of such a space-based observatory is to measure UHECRs and UHE neutrinos with high statistics and uniform exposure. EUSO-SPB2 is designed with two Schmidt telescopes, each optimized for their respective observational goals. The Fluorescence Telescope looks at the nadir to measure the fluorescence emission from UHECR-induced extensive air shower (EAS), while the Cherenkov Telescope is optimized for fast signals (∼10 ns) and points near the Earth's limb. This allows for the measurement of Cherenkov light from EAS caused by Earth skimming VHE neutrinos if pointed slightly below the limb or from UHECRs if observing slightly above. The expected launch date of EUSO-SPB2 is Spring 2023 from Wanaka, NZ with target duration of up to 100 days. Such a flight would provide thousands of VHECR Cherenkov signals in addition to tens of UHECR fluorescence tracks. Neither of these kinds of events have been observed from either orbital or suborbital altitudes before, making EUSO-SPB2 crucial to move forward towards a space-based instrument. It will also enhance the understanding of potential background signals for both detection techniques. This contribution will provide a short overview of the detector and the current status of the mission as well as its scientific goals., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

Multi-messenger observations of transient astrophysical sources have the potential to characterize the highest energy accelerators and the most extreme environments in the Universe. Detection of neutrinos, in particular tau neutrinos generated by neutrino oscillations in transit from their sources to Earth, is possible for neutrino energies above 10 PeV using optical Cherenkov detectors imaging upward-moving extensive air showers (EAS). These EAS are produced from Earth-interacting tau neutrinos leading to tau leptons that subsequently decay in the atmosphere. We compare neutrino detection sensitivities for generic short- and long-burst transient neutrino sources and sensitivities to the diffuse neutrino flux for the second generation Extreme Universe Space Observatory on a Super-Pressure Balloon (EUSO-SPB2) balloon-borne mission and the proposed space-based Probe of Extreme Multi-Messenger Astrophysics (POEMMA) mission., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

The Extreme Universe Space Observatory Super Pressure Balloon 2 (EUSO-SPB2) is under development, and will prototype instrumentation for future satellite-based missions, including the Probe of Extreme Multi-Messenger Astrophysics (POEMMA). EUSO-SPB2 will consist of two telescopes. The first is a Cherenkov telescope (CT) being developed to identify and estimate the background sources for future below-the-limb very high energy (E>10 PeV) astrophysical neutrino observations, as well as above-the-limb cosmic ray induced signals (E>1 PeV). The second is a fluorescence telescope (FT) being developed for detection of Ultra High Energy Cosmic Rays (UHECRs). In preparation for the expected launch in 2023, extensive simulations tuned by preliminary laboratory measurements have been performed to understand the FT capabilities. The energy threshold has been estimated at 1018.2 eV, and results in a maximum detection rate at 1018.6 eV when taking into account the shape of the UHECR spectrum. In addition, onboard software has been developed based on the simulations as well as experience with previous EUSO missions. This includes a level 1 trigger to be run on the computationally limited flight hardware, as well as a deep learning based prioritization algorithm in order to accommodate the balloon's telemetry budget. These techniques could also be used later for future, space-based missions., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

K-EUSO is a planned mission of the JEM-EUSO program for the study of ultra-high energy cosmic rays (UHECR) from space, to be deployed on the International Space Station. The K-EUSO observatory consists of a UV telescope with a wide field of view, which aims at the detection of fluorescence light emitted by extensive air showers (EAS) in the atmosphere. The EAS events will be sampled with a time resolution of 1-2.5 μs to reconstruct the entire shower profile with high precision. The detector consisting of ∼ 105 independent pixels will allow a spatial resolution of ∼700 m on ground. From a 400 km altitude, K-EUSO will achieve a large and full sky exposure to sample the highest energy range of the UHECR spectrum. In this contribution, we present estimates of the performance of the observatory: an estimation of the expected exposure and triggered event rate as a function of energy and the event reconstruction performance, including resolution of arrival directions and energy of UHECRs., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference

Pre-registration for the study named "The effects of emotional thinking styles on mood and memory".

Astrophysical ultra-high energy (UHE) neutrinos let us look inside the accelerators of ultra-high energy cosmic rays (UHECR), study the composition of UHECR, and study neutrino physics at the highest energies. We aim to detect Earth-skimming UHE tau neutrinos with the atmospheric imaging Cherenkov technique. Towards that goal, we are developing a prototype Cherenkov telescope that is scheduled to fly in 2022 on a long-duration balloon flight, the Extreme Universe Space Observatory Super Pressure Balloon 2 (EUSO-SPB2). In this poster, we present the status of development of the Cherenkov camera, optics, and sensitivity studies of the telescope.