Sökning: "transmitter architecture"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden transmitter architecture.

1. 1. CALLUM Linear Transmitter - Architecture and Circuit Analysis

   Författare :Roland Strandberg; Institutionen för elektro- och informationsteknik; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

3. 2. All Digital Polar Transmitter Design for Software Defined Radio : Architecture and Low Power Circuit Implementation

   Författare :Liang Rong; Li-Rong Zheng; Henrik Sjöland; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Switching Power Amplifier; All Digital Polar Transmitter; Lowpass Sigma Delta Modulation; Software Defined Radio; RFID; H-Bridge Architecture; Resonating; Filter Matching Network.; SRA - ICT; SRA - Informations- och kommunikationsteknik;

   Sammanfattning : The evolving wireless communication technology is aiming highdata rate, high mobility, long distance and at the meantime, co-existwith various different standards. This developing trend requires ahighly linear transceiver system and it causes the problem of lowefficiency due to the large crest factor of signals. LÄS MER

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

   Författare :Jian Chen; Li-Rong Zheng; Fredrik Jonsson; Hannu Tenhunen; Georges Gielen; KTH; []
   Nyckelord :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.;

   Sammanfattning : 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. LÄS MER

5. 4. Linear Transmitter Design Using Nonlinear Analog Circuits

   Författare :Bo Shi; Institutionen för elektro- och informationsteknik; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

7. 5. Behavioral modeling of wireless transmitters for distortion mitigation

   Författare :Ali Soltani Tehrani; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear models; wireless communications.; computational complexity; I Q imbalance; digital predistortion; Volterra series; transmitter; power amplifier; Behavioral modeling;

   Sammanfattning : As the demand for high speed and reliable wireless communication increases, theimportance of having a linear transmitter has enhanced. Distortions created by thetransmitter, such as power amplifier nonlinearity and I/Q imbalance, diminish thefidelity and limit the performance of wireless systems, if left undealt with. LÄS MER