Sökning: "antenna characterization"

Visar resultat 1 - 5 av 53 avhandlingar innehållade orden antenna characterization.

  1. 1. Characterization of artificially soft surfaces and their applications in antenna design

    Författare :Zhinong Ying; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dipole antenna; UTD; GPS; broadband antennas; circular polarization; feed; moment method; soft and hard surfaces; surface impeddance; corrugated horn; antennas; multipath effect; microstrip antenna; magnetic coating; spiral antenna; corrugated surface; dielectric loaded surface; ground plane; slot antenna; monopole antenna; helical antenna; choke-ring;

    Sammanfattning : .... LÄS MER

  3. 2. Embedded Element Patterns in Combination with Circuit Simulations for Multi-Port Antenna Analysis

    Författare :Kristian Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna efficiency; Greens function; multi-port antenna; impedance matching; reverberation chamber; correlation; antenna arrays; Embedded element pattern; optimization; antenna diversity;

    Sammanfattning : This thesis is a result from work on two different subjects, electromagnetic simulations of reverberation chambers and a methodology for the analysis of multi-port antennas. The subjects can be linked together by their contribution to knowledge in electromagnetic simulations and characterization of antennas. LÄS MER

  4. 3. 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

  5. 4. Design, Characterization, and Calibration of Low-Noise Terahertz Receivers

    Författare :Olle Nyström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; receiver characterization; instrumentation; antenna design; Radio astronomy; calibration; optics;

    Sammanfattning : This thesis is focused on the field of instrumentation for radio-astronomy and atmospheric science, and specifically deals with problems such as optical design and its verification, horn antennas and receiver optics’ components, different aspects of measurement systems in order to characterize low-noise THz receivers, and its calibration techniques.Ultra low-noise Terahertz receivers, used in radio-astronomy, are typically coupled to the telescope system through relay optics that provides guiding of the signal to the receiver frontend with minimal loss. LÄS MER

  7. 5. Modeling and Compensation of Nonlinear Distortion in Multi-Antenna RF Transmitters

    Författare :Katharina Hausmair; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multi-antenna transmitter; behavioral modeling; over-the-air characterization; digital predistortion; antenna crosstalk; linearization; power amplifier;

    Sammanfattning : Multi-antenna systems are utilized as a way to increase spectral efficiency in wireless communications. In a transmitter, the use of several parallel transmit paths and antennas increases system complexity and cost. Cost-efficient solutions, which employ active antenna arrays and avoid expensive isolators, are therefore preferred. LÄS MER