Aleksandar Angelovski

High bandwidth pickup design for bunch arrival-time monitors for free-electron laser

In this paper, we present the design and realization of high bandwidth pickup electrodes with a cutoff frequency above 40 GHz. The proposed cone-shaped pickups are part of a bunch arrival-time monitor designed for high ( > 500 pC) and low (20 pC) bunch charge operation mode providing for a time resolution of less than 10 fs for both operation modes. The proposed design has a fast voltage response, low ringing, and a resonance-free spectrum. For assessing the influence of manufacturing tolerances on the performance of the pickups, an extensive tolerance study has been performed via numerical simulations. A nonhermetic model of the pickups was built for measurement and validation purposes. The measurement and simulation results are in good agreement and demonstrate the capability of the proposed pickup system to meet the given specifications.

Helix-shaped CRLH-mass flow detector for the cross-sectional detection of inhomogeneous distributed pneumatic conveyed pulverized solids

This paper presents an application of a Composite Right/Left-Handed (CRLH) Transmission Line resonator for a compact mass flow detector with increased sensitivity compared to a conventional microwave mass flow detector. In this concept series capacitors and shunt inductors are used to synthesize a medium with simultaneously negative permeability and permittivity — the so called metamaterial. The simultaneous detection of the velocity and solids/air concentration from a single measurement, ensures a true mass flow detector. The rearrangement of two CRLH-TL resonators to a helix shape opens the possibility to detect the cross-sectional flow distribution of the fed material in order to increase the accuracy of the detector. A prototype was realized and tested in a dedicated measurement setup to prove the concept. The application areas of this sensor are gas/solids, gas/liquid and liquid/solids flows in various industrial monitoring applications.

Moisture insensitive microwave mass flow detector for particulate solids

A novel moisture insensitive mass flow detector based on a mass flow sensor with open an cylindrical resonator is presented in this paper. The mass flow sensor consists of two MicroStrip Patch couplers integrated in a Composite Right-/Lefthanded Transmission line resonator. The design of a particulate mass flow detector based on this sensor is given and the algorithm to detect the average solids concentration is shown. The simultaneous detection of the velocity and the moisture independent solids/air concentration from a single measurement, ensures a true mass flow detector. Since it was already shown formerly, both sensor principles are able to measure the moisture dependent mass flow rate with high precision, we expect for the combination of both principles a detection accuracy in the range of both single sensor principles. Measurements of natural substance granulate with different amounts of moisture up to 18% (vol.) were done. The rearrangement of the CRLH-TL resonator to a helix shape opens the possibility to detect of the cross-sectional flow distribution of the fed material. Simulations and measurements of a helix shaped CRLH-TL resonator were done in order to proof the concept. The novel detector design is promising for industrial applications with various scenarios of gas/solids, gas/liquid and liquid/solids flows.

Energy beam position monitor design utilizing grounded coplanar waveguide transmission line pickups and a modified six-port discriminator for particle accelerators

Energy beam position monitors (EBPM) based on grounded co-planar waveguide (CPW) transmission lines have been designed for installation in the dispersive sections of the bunch compressor chicanes at the future European X-ray Free Electron Laser research facility (XFEL) located in Germany [1]. After completion, the European XFEL will generate extremely intense X-ray flashes with the properties of laser light and intensities much brighter than those produced by other light sources.

Mikrowellenbasierter Massendurchflusssensor auf Basis von zweidimensionalen linkshändigen Leitungsstrukturen

Zusammenfassung In diesem Beitrag wird eine Anwendung eines kompakten Massendurchflusssensors auf Basis von resonanten “Kompositen Rechts-/Linkshändigen” Leitungsstrukturen (CRLH) mit erhöhter Empfindlichkeit im Vergleich zu herkömmlichen, mikrowellenbasierten Sensoren zur Bestimmung des Massenstroms in pneumatischen Förderanlagen vorgestellt. Das Konzept besteht aus einer periodischen Struktur von in Reihe geschalteten Kondensatoren und parallel geschalteten Induktivitäten mit makroskopisch negativer Permeabilität und Permittivität — den sogenannten Metamaterialien. Die simultane Erfassung der Geschwindigkeit und der Feststoff/Luft-Konzentration aus einer einzigen Messung ermöglicht die Messung des Massendurchflusses in Echtzeit. Die Anordnung einer oder mehrerer CRLH-Leitungsstrukturen zu einer Spiralform, eröffnet weiterhin die Möglichkeit, die Verteilung des Durchflusses über dem Förderrohrquerschnitt des Materials zu bestimmen, um die Genauigkeit des Sensors zu erhöhen. Zur Überprüfung des Sensorkonzeptes wurde ein Prototyp aufgebaut und in einem dedizierten Messsystem vermessen. Mögliche Anwendungsgebiete dieser Sensoren sind die Bestimmung des Massendurchflusses von Luft/Feststoff-, Luft/Flüssigkeit- und Flüssigkeit/Feststoff-Mischungen in der industriellen Prozessüberwachung. Abstract This paper presents an application of a Composite Right/Left-Handed Transmission Line resonator (CRLH-TL) for a compact mass flow detector with increased sensitivity compared to a conventional microwave mass flow detector. In this concept, series capacitors and shunt inductors are used to synthesize a medium with simultaneously negative permeability and permittivity — the so called metamaterial. The simultaneous detection of the velocity and the solids/air concentration from a single measurement ensures a true mass flow detector. The arrangement of two CRLH-TL resonators to a helix shape opens up the possibility to detect the cross-sectional flow distribution of the material fed thereby increasing the accuracy of the detector. A prototype was realized and tested in a dedicated measurement setup to prove the concept. The application areas of this sensor are gas/solids, gas/liquid and liquid/solids flows in industrial monitoring applications.

CRLH-TL Sensors for Flow Inhomogeneties Detection of Pneumatic Conveyed Pulverized Solids

Abstract This paper presents an application of a Composite Right/Left-Handed (CRLH) Transmission Line resonator for a compact mass flow detector which is able to detect inhomogeneous flows. In this concept, series capacitors and shunt inductors are used to synthesize a medium with simultaneously negative permeability and permittivity – the so called metamaterial. The helix shape of the cylindrical CRLH-TL sensor offers the possibility to detect flow inhomogeneities within the pipeline which can be used to correct the detected massflow rate. A combination of two CRLH-TL structures within the same cross-section of the pipeline can improve the angular sensitivity of the sensor. A prototype was realized and tested in a dedicated measurement setup to prove the concept.