Advanced search

Showing result 1 - 5 of 264 swedish dissertations matching the above criteria.

2. 1. Transmitter Linearization for mm-Wave Communications Systems

   Author : Halil Volkan Hünerli; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; linearization; transmitter; mm-wave power amplifier; Eband; analog predistorter; digital predistortion;

   Abstract : There is an ever increasing need for enabling higher data rates in modern communication systems which brings new challenges in terms of the power consumption and nonlinearity of hardware components. These problems become prominent in power amplifiers (PAs) and can significantly degrade the performance of transmitters, and hence the overall communication system. READ MORE

4. 2. Active Transmitter Antenna Array Modeling for MIMO Applications

   Author : Parastoo Taghikhani; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beam steering; Active antenna array; active impedance; hybrid beamforming transmitter; MIMO transmitter; far-field nonlinear distortion; millimeter wave; modeling.;

   Abstract : The rapid growth of data traffic in mobile communications has attracted interests to the Multiple-Input-Multiple-Output (MIMO) communication systems at millimeter-wave (mmWave) frequencies.  MIMO systems exploit active transmitter antenna arrays for higher energy efficiency and providing beamforming flexibility. READ MORE

5. 3. Low Noise Oscillator in ADPLL toward Direct-to-RF All-digital Polar Transmitter

   Author : Jian Chen; Li-Rong Zheng; Fredrik Jonsson; Hannu Tenhunen; Georges Gielen; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; all-digital; digitally-intensive; frequency modualtion; phase modulation; amplitude modulation; polar; transmitter; oscillator; digital controled oscillator; DCO; VCO; voltage controled oscillator; class-C oscillator; class-D PA; ADPLL; phase noise; RF; CMOS.;

   Abstract : In recent years all-digital or digitally-intensive RF transmitters (TX) have attracted great attention in both literature and industry. The motivation is to implement RF circuits in a manner suiting advanced nanometer CMOS processes. To achieve that, information is encoded in the time-domain rather than voltage amplitude. READ MORE

6. 4. Linear Transmitter Design Using Nonlinear Analog Circuits

   Author : Bo Shi; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telecommunication engineering; Elektronik och elektroteknik; Electronics and Electrical technology; BiCMOS.; CMOS; ASIC; Radio-frequency circuits; Translinear circuits; RF power amplifier linearization; Linear transmitter; Nonlinear analog circuits; Telekommunikationsteknik;

   Abstract : This dissertation deals with analog techniques at both the architecture and circuit design levels for designing power efficient linear radio-frequency (RF) transmitters. The use of nonlinear analog integrated circuits to implement certain critical signal processing functions for the multiplicative feedback and LINC techniques is investigated with the aim of improving the system performance in terms of complexity, linearity and power efficiency. READ MORE

7. 5. CALLUM Linear Transmitter - Architecture and Circuit Analysis

   Author : Roland Strandberg; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telekommunikationsteknik; Telecommunication engineering; loop time delay; modulation negative feedback; spectral emissions; baseband model; CALLUM; Linear transmitter architecture; power amplifier linearization;

   Abstract : This doctoral dissertation presents a study of linear radio transmitters based on the combined analog locked loop universal modulator (CALLUM) approach. Linear architectures such as CALLUM are very attractive for power-efficient operations, since they have no fundamental limitations prohibiting a 100% efficiency for all envelope levels, without sacrificing the potential of a linear transmission. READ MORE