Sökning: "Focal Plane array"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Focal Plane array.

1. 1. Miniaturized Hard Waveguides in Multifunction Array Antennas

   Författare :Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interlaced arrays; Floquet theorem; reflector antennas; focal plane array; multifunction antennas; miniaturized waveguides; multilayer structures; spectral domain technique; periodic structures; aperture reuse; method of moments; soft and hard surfaces; array antennas;

   Sammanfattning : Recent advances in technologies of wireless communications systems have led to an increasing desire for several antennas performing diverse functions at different frequencies to be integrated into a common radiating aperture. This gives rise to the so-called multifunction antenna, which affords the saving of scarce premium real estate and can alleviate problems arising from excessive antenna protrusions in aspects such as aerodynamics, aesthetics, and stealth capability in military applications. LÄS MER

3. 2. On millimeter and submillimeter wave focal plane arrays implemented with MEMS waveguide switches

   Författare :Henrik Frid; Joachim Oberhammer; Vessen Vassilev; Mikro- och nanosystemteknik KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Extended Hemispherical Lens; Beam Steering; Focal Plane Array FPA ; Ray-Tracing; RF MEMS; waveguide switch; micromachined waveguide; submillimeter-wave; rectangular waveguide; terahertz; lenses; antenna theory; silicon; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : This thesis presents research towards enabling micromachined millimeter and submillimeter wave focal plane arrays (FPAs). The FPAs operate under the following principle: a switch network consisting of microelectromechanical (MEMS) switches, integrated with micromachined waveguides, is used to feed an array of antenna elements, located in the focal plane of a high-gain quasi-optical system. LÄS MER

4. 3. Digital Beamforming Focal Plane Arrays for Radio Astronomy and Space-Borne Passive Remote Sensing

   Författare :Oleg Iupikov; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beamforming; spaceborne radiometers; radio telescopes; phased array feeds; reflector antenna feeds; feed-reflector interaction;

   Sammanfattning : Dense Phased Array Feeds (PAFs) for reflector antennas have numerous advantages over traditional cluster feeds of horns in a one-horn-per-beam configuration, especially in RF-imaging applications which require multiple simultaneously formed and closely overlapping beams. However, the accurate analysis and design of such PAF systems represents a challenging problem, both from an EM-modeling and beamforming optimization point of view. LÄS MER

5. 4. Frequency Selective Cold-Electron Bolometer Arrays

   Författare :Sumedh Mahashabde; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mm-wave detectors; Cold-Electron Bolometer; Frequency Selective Surface; Focal Plane array; OLIMPO; LSPE;

   Sammanfattning : This work presents the integration of the Cold-Electron Bolometer (CEB) in Frequency Selective Surface (FSS) based arrays targeting balloon-borne telescope missions with high incident power requirements (typically tens of pW). FSS are planar frequency sensitive structures typically consisting of repeating pattern of a simple motif like square, circle, etc. LÄS MER

7. 5. Mm-wave Radio Astronomy Instrumentation for the Onsala Space Observatory and SEST

   Författare :Nicholas D. Whyborn; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mm-wave receiver; phase retrieval holography; focal plane imaging array; radio astronomy instrumentation; SIS mixer;

   Sammanfattning : The thesis presents work done in developing instrumentation for mm- and submm-wave radio astronomy. The work described is in several fields. The greater part of the thesis is concerned with sensitive heterodyne receivers and in particular the cryogenically cooled mixers. In paper A the SEST telescope and its observing system are described. LÄS MER