Sökning: "Line-of-sight LOS"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden Line-of-sight LOS.

1. 1. The Random Line-of-Sight Over-the-Air Measurement System

   Författare :Madeleine Schilliger Kildal; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; random line-of-sight; anechoic chamber; reverberation chamber; over-the-air; vehicular communication; wireless communication; throughput; rich isotropic multipath;

   Sammanfattning : As our society becomes increasingly connected, a growing number of devices rely on wireless connectivity. The type, use and form factor of these devices range from wearables to entire vehicles. Additionally, the fifth generation of wireless communication (5G) introduces new communication bands, also at higher frequencies. LÄS MER

3. 2. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Multipath & Line-of-Sight

   Författare :Ahmed Hussain; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; USRP; OTA; SDR; RIMP; TRP; TIS; Reverberation chamber; Rayleigh; MIMO; LOS; LTE; Throughput;

   Sammanfattning : The current thesis investigates over-the-air (OTA) performance characterization of small antennas and wireless terminals in rich isotropic multipath (RIMP) environment, as well as in pure line-of-sight (LOS) environment when taking into account the random positions and orientations of the mobile terminals caused by the realistic user behavior. The latest mobile wireless terminals such as smart phones and tablets can be used in any random orientation thereby making even a received LOS-component appear as a random voltage at the antenna ports over time. LÄS MER

4. 3. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Rich Isotropic Multipath & Random Line-of-Sight

   Författare :Ahmed Hussain; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; Rayleigh; reverberation chamber; random LOS; RIMP; LTE; OTA;

   Sammanfattning : The current thesis is about over-the-air (OTA) performance characterization of wireless terminals in rich isotropic multipath (RIMP) environment as well as in pure line-of-sight (LOS) environment while not ignoring the random positions and orientations of the mobile terminals due to randomness of the user. The latest mobile wireless terminals such as iPhone and iPad can be used in any random position and orientation thereby making the received LOS-component toappear as a random voltage at the antenna ports. LÄS MER

5. 4. Evaluation of the Random-LOS Measurement System for Vehicular Communication Applications

   Författare :Madeleine Schilliger Kildal; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reverberation Chamber; Over-the-Air; Anechoic Chamber; Random Line-of-Sight; Rich Isotropic Multipath; wireless communication; car measurements; throughput;

   Sammanfattning : The automotive industry is progressively closing on the Telecom industry as wireless data connection and transmission become more and more important for vehicles. In both future and present cars, the safety and infotainment systems depend on reliable wireless data transmission. This is especially the case when autonomous cars will reach the market. LÄS MER

7. 5. Characterization and Design Requirements for Antennas in the Near-field and the Random-LOS Propagation Environment

   Författare :Aidin Razavi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization-MIMO; Random-LOS; OTA; Antenna measurements; near-field antennas; antenna characterization; MIMO; near-field focusing;

   Sammanfattning : The choice of antenna for a particular application depends on the requirements imposed by that application. These can be, the application's field region (i.e., near-field or far-field), polarization, radiation pattern, radiation efficiency, system throughput, etc. LÄS MER