Sökning: "Antenna Array"

Visar resultat 21 - 25 av 150 avhandlingar innehållade orden Antenna Array.

1. 21. Wireless Sensor Network Systems in Harsh Environments and Antenna Measurement Techniques

   Författare :Mathias Grudén; Anders Rydberg; Mikael Gidlund; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless Sensor Network; Antenna; Jet engine; Train; Reverberation chamber; WISENET; Wisejet; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

   Sammanfattning : Wireless sensor network (WSN) has become a hot topic lately. By using WSN things that previously were difficult or impossible to measure has now become available. One of the main reasons using WSN for monitoring is to save money by cost optimization and/or increase safety by letting the user knowing the physical status of the monitored structure. LÄS MER

3. 22. Mobile Antenna Systems for 4G and 5G Applications with User Body Interaction

   Författare :Kun Zhao; Sailing He; Cyril Luxey; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Antenna; MIMO; mmWave; Mobile communication; SAR; Power density; User body effect; Channel modeling; Multiplex efficiency; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : In the thesis, the user body effect on antennas in a mobile terminal is discussed. In order to overcome the degradation of Multiple-Input Multiple-Output (MIMO) performance due to the user body effect, a quad-elements MIMO antenna array which can mitigate the body effect through an adaptive antenna switching method is introduced for 4G mobile terminals. LÄS MER

4. 23. Signal Processing for Radar with Array Antennas and for Radar with Micro-Doppler Measurements

   Författare :Svante Björklund; Mats Pettersson; Ingvar Claesson; Ulrich Nickel; Blekinge Tekniska Högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; radar; signal processing; array antenna; subarray; clutter; jamming; interference; direction of arrival estimation; security; micro-Doppler; feature extraction; classification;

   Sammanfattning : Radar (RAdio Detection And Ranging) uses radio waves to detect the presence of a target and measure its position and other properties. This sensor has found many civilian and military applications due to advantages such as possible large surveillance areas and operation day and night and in all weather. LÄS MER

5. 24. On the Adaptive Array Problem

   Författare :Mats Viberg; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direction-of-Arrival; Signal to Noise Ratio; Adaptive array problem; Radio communication system;

   Sammanfattning : By an array we mean a set of coupled sensors, typically antenna elements. The array receives superimposed signals from distant sources. By combining the outputs of the sensors in different ways, one can change the array sensitivity to different Directions-of-Arrival (DOA). LÄS MER

7. 25. Sparse Array Architectures for Wireless Communication and Radar Applications

   Författare :Navid Amani; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; base station antenna BSA ; sparse array; grating lobe; multi-user MU MIMO; multipath channel; mutual coupling; direction-of-arrival DOA estimation; MIMO radar; 5G; network theory;

   Sammanfattning : This thesis focuses on sparse array architectures for the next generation of wireless communication, known as fifth-generation (5G), and automotive radar direction-of-arrival (DOA) estimation. For both applications, array spatial resolution plays a critical role to better distinguish multiple users/sources. LÄS MER