Sökning: "millimetre wave imaging"

Hittade 5 avhandlingar innehållade orden millimetre wave imaging.

1. 1. Photonic terahertz-wave generation, radiation and quasioptical integration

   Författare :Biddut Kumar Banik; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; semiconductor device modelling; semiconductor diodes; III-V semiconductors; Catadioptric lens; imaging; dipole antennas; slot antennas; lens antennas; semiconductor heterojunctions; dielectric loaded antennas; optical mixers; photomixers; near-field imaging; computer aided engineering; indium compounds; millimetre wave imaging; near-field optics; submillimeter wave generation; photodiodes; terahertz sources; millimetre wave generation; submillimetre wave integrated circuits; microwave imaging; uni-travelling-carrier photodiodes;

   Sammanfattning : This thesis deals with the uni-travelling-carrier photodiode (UTC-PD) based photonic generation of terahertz waves, antenna designs for the terahertz radiation and a novelcatadioptric lens for quasioptical integration.The ongoing and accomplished research work on the UTC-PD, its limitations and optimisation scopes for attaining higher bandwidth and higher output power have been discussed. LÄS MER

3. 2. Millimetre wave waveguide enclosed grid frequency multipliers and imaging

   Författare :Robin Dahlbäck; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Millimeter wave; THz imaging; THz sources; Grid; Heterostructure Barrier Var- actors HBVs ; Varactors; Array; FMCW; 2D-grid; Quasi-optical.; Frequency multipliers; Radars; sub-millimetre waves; Schottky diodes;

   Sammanfattning : The utilisation of the THz spectrum ( 0.3-10 THz ) is hampered by fundamental difficulties in generating power at these frequencies. LÄS MER

4. 3. Photonic THz Generation and Quasioptical Integration for Imaging Applications

   Författare :Biddut Kumar Banik; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nondestructive evaluation; semiconductor device modelling; uni-travelling-carrier photodiodes; millimetre wave and submillimetre wave generation; III-V semiconductors; photomixers; terahertz sources.; catadioptric lens; microwave imaging; dielectric loaded antennas; terahertz imaging; lens antennas; millimetre wave and submillimetre wave imaging;

   Sammanfattning : This thesis deals with the analysis and optimisation of the uni-travelling-carrier photodiode (UTC-PD) for continuous-wave generation in terahertz (THz) frequencyrange. Photonic THz generation using UTC-PDs is extremely promising as it offers wide tunability, adequate output power and room temperature operation. LÄS MER

5. 4. Reconfigurable and Wideband Receiver Components for System-on-Chip Millimetre-Wave Radiometer Front-Ends

   Författare :Shakila Bint Reyaz; Robert Malmqvist; Anders Rydberg; Luca Roselli; Uppsala universitet; []
   Nyckelord :Reconfigurable; Wideband; Receivers; Millimetre-Wave; Radiometers; System-on-Chip; Passive Imaging.; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

   Sammanfattning : This thesis presents solutions and studies related to the design of reconfigurable and wideband receiver circuits for system-on-chip (SoC) radiometer front-ends within the millimetre-wave (mm-wave) range. Whereas many of today’s mm-wave front-ends are bulky and costly due to having discrete RF components, single-chip receiver modules could potentially result in a wider use for emerging applications such as wireless communication, short range radar and passive imaging security sensors if realised with adequate performances and at a lower cost. LÄS MER

7. 5. Compact and Efficient Millimetre-Wave Circuits for Wideband Applications

   Författare :Lars Ohlsson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; resonant-tunnelling diode; millimetre-wave spectrum; integrated transmitter; energy-efficiency; compact circuit; dielectric resonator antenna; transistor; wavelet generator; wideband.;

   Sammanfattning : Radio systems, along with the ever increasing processing power provided by computer technology, have altered many aspects of our society over the last century. Various gadgets and integrated electronics are found everywhere nowadays; many of these were science-fiction only a few decades ago. LÄS MER