Search for dissertations about: "Array antennas"

Showing result 1 - 5 of 111 swedish dissertations containing the words Array antennas.

2. 1. Miniaturized Hard Waveguides in Multifunction Array Antennas

   Author : Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

4. 2. Printable Green RFID Antennas for Embedded Sensors

   Author : Yasar Amin; Hannu Tenhunen; Lirong Zheng; Qiang Chen; Leena Ukkonen; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; RFID; Antennas; Inkjet printing; Wideband Antennas; Narrow-band Antennas;

   Abstract : In the recent years, radio-frequency identification (RFID) technology has been widely integrated into modern society applications, ranging from barcode successor to retail supply chain, remote monitoring, detection and healthcare, for instance. In general, an RFID tag or transponder is composed of an antenna and an application-specific integrated circuit chip. READ MORE

5. 3. Predictor Antennas : Enabling channel prediction for fast-moving vehicles in wireless broadband systems

   Author : Joachim Björsell; Mikael Sternad; Anders Ahlén; Fredrik Tufvesson; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Predictor antenna; Channel prediction; Long-range prediction; Massive MIMO; Spline interpolation; Channel aging; Outdated CSI; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

   Abstract : Many advanced transmission techniques utilize channel state information (CSI) at the transmitter (CSIT) to improve throughput, spectral efficiency, power efficiency, and other performance metrics. Estimating CSI accurately is important to fully benefit from many of these techniques. READ MORE

6. 4. Phased array calibration and beamforming using signal processing

   Author : Maria Lanne; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mutual coupling; calibration; array imperfections; beampattern synthesis; adaptive beamforming; convex optimization.; array signal processing; Array antennas;

   Abstract : Array antennas have a wide range of applications which includesground and airborne radar, weather radar and anti-collision radar.In addition, equally important applications exist forcommunications, both on earth and to satellites in space, as wellas for medical applications such as the detection and treatment oftumors. READ MORE

7. 5. Dielectrically Loaded Quad-ridge Flared Horns for Ultra Wideband Reflector Feed Applications in Radio Astronomy

   Author : Jonas Flygare; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric loaded antennas; dielectric materials; reflector antenna feeds; radio astronomy; ultra wideband antennas; quad-ridge flared horn qrfh ; radio receivers; horn antennas; broadband antennas; aperture antennas.;

   Abstract : Reflector-based radio telescopes are used as tools for observations in both radio astronomy and space geodesy. To observe the weak sources in space, highly sensitive receivers, fronted by optimized reflector feeds, are therefore needed. READ MORE