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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Ultra-Low Noise and Highly Linear Two-Stage Low Noise Amplifier (LNA)

Cherukumudi, Dinesh January 2011 (has links)
An ultra-low noise two-stage LNA design for cellular basestations using CMOS is proposed in this thesis work.  This thesis is divided into three parts. First, a literature survey which intends to bring an idea on the types of LNAs available and their respective outcomes in performances, thereby analyze how each design provides different results and is used for different applications. In the second part, technology comparison for 0.12µm, 0.18µm, and 0.25µm technologies transistors using the IBM foundry PDKs are made to analyze which device has the best noise performance. Finally, in the third phase bipolar and CMOS-based two-stage LNAs are designed using IBM 0.12µm technology node, decided from the technology comparison. In this thesis a two-stage architecture is used to obtain low noise figure, high linearity, high gain, and stability for the LNA. For the bipolar design, noise figure of 0.6dB, OIP3 of 40.3dBm and gain of 26.8dB were obtained. For the CMOS design, noise figure of 0.25dB, OIP3 of 46dBm and gain of 26dB were obtained. Thus, the purpose of this thesis is to analyze the LNA circuit in terms of design, performance, application and various other parameters. Both designs were able to fulfill the design goals of noise figure < 1 dB, OIP3 > 40 dBm, and gain >18 dB.
12

Design Aspects of Fully Integrated Multiband Multistandard Front-End Receivers

Adiseno, January 2003 (has links)
<p>In this thesis, design aspects of fully integrated multibandmultistandard front-end receivers are investigated based onthree fundamental aspects: noise, linearity and operatingfrequency. System level studies were carried out to investigatethe effects of different modulation techniques, duplexing andmultiple access methods on the noise, linearity and selectivityperformance of the circuit. Based on these studies and thelow-cost consideration, zero-IF, low-IF and wideband-IFreceiver architectures are promising architectures. These havea common circuit topology in a direct connection between theLNA and the mixer, which has been explored in this work toimprove the overall RF-to-IF linearity. One front-end circuitapproach is used to achieve a low-cost solution, leading to anew multiband multistandard front-end receiver architecture.This architecture needs a circuit whose performance isadaptable due to different requirements specified in differentstandards, works across several RF-bands and uses a minimumamount ofexternal components.</p><p>Five new circuit topologies suitable for a front-endreceiver consisting of an LNA and mixer (low-noise converter orLNC) were developed. A dual-loop wide-band feedback techniquewas applied in all circuits investigated in this thesis. Threeof the circuits were implemented in 0.18 mm RF-CMOS and 25 GHzbipolar technologies. Measurement results of the circuitsconfirmed the correctness of the design approach.</p><p>The circuits were measured in several RF-bands, i.e. in the900 MHz, 1.8 GHz and 2.4 GHz bands, with S11 ranging from–9.2 dB to–17 dB. The circuits have a typicalperformance of 18-20 dB RF-to-IF gain, 3.5-4 dB DSB NF and upto +4.5 dBm IIP3. In addition, the circuit performance can beadjusted by varying the circuit’s first-stage biascurrent. The circuits may work at frequencies higher than 3GHz, as only 1.5 dB of attenuation is found at 3 GHz and nopeaking is noticed. In the CMOS circuit, the extrapolated gainat 5 GHz is about 15 dB which is consistent with the simulationresult. The die-area of each of the circuits is less than 1mm2.</p>
13

Optimization through Co-Simulation of Antenna, Bandpass Filter and Low-Noise Amplifier at 6-9 GHz

Khan, Abbas January 2012 (has links)
Ultra-wide band (UWB) 6-9 GHz antenna, band pass filter and low-noise amplifier (LNA) optimization using co-simulation of the RF front-end. At higher frequencies, carefully conducted design methodologies are required for RF front-end parameter optimization, such as power gain and low noise figure with low power consumption.
14

Projeto de um amplificador de baixo ruído em tecnologia CMOS 130nm para frequências de 50MHZ a 1GHz / A 50MHz-1GHz wideband low noise amplifier in 130nm CMOS technology

Pimentel, Henrique Luiz Andrade January 2012 (has links)
O presente trabalho tem por objetivo fornecer o embasamento teórico para o projeto de um amplificador de baixo ruído (LNA – Low Noise Amplifier) em tecnologia CMOS que opere em mais de uma faixa de frequência, de modo a permitir seu uso em receptores multibanda e de banda larga. A base teórica que este trabalho abrange desde a revisão bibliográfica do assunto em questão, passando pela análise dos modelos de transistores para alta-frequência, pelo estudo das especificações deste bloco e das métricas utilizadas em projetos de circuitos integrados de RF, bem como pela revisão de topologias clássicas existentes. Com os conhecimentos acima adquiridos, foi possível realizar o projeto de um LNA diferencial de banda larga utilizando tecnologia CMOS IBM 130nm, o qual pode ser aplicado ao padrão IEEE 802.22 para rádios cognitivos (CR). O projeto é baseado na técnica de cancelamento de ruído, sendo validado após apresentar efetiva redução de figura de ruído para banda de frequência desejada, com moderado consumo de potência e utilização moderada de área de silício, devido a solução sem o uso de indutores. O LNA banda larga opera em frequências de 50Mhz a 1GHz e apresenta uma figura de ruído abaixo de 4dB, em 90% da faixa, um ganho acima de 12dB, e perda de retorno na entrada e na saída maiores que 12dB. O IIP3 e a frequência de ocorrência de compressão a 1dB com a entrada em 580MHz estão acima de 0dBm e -10dBm respectivamente. Possui consumo de 46,5mWpara fonte de 1,5V e ocupa uma área ativa de apenas 0,28mm x 0,2mm. / This work presents the theoretical basis for the design of a low noise amplifier (LNA) in CMOS technology that operates in more than one frequency band, which enables its use in multi-band and wideband receivers. The theoretical basis that this work will address extends from the literature review on the subject, through the analysis of models of MOS transistors for high frequencies, study of specifications of this block and the metrics used in RF integrated circuit design, as well as the review of existing classical LNA topologies. Based on the knowledge acquired above, the design of a differential wideband LNA is developed using IBM 130nm RF CMOS process, which can be used in IEEE 802.22 Cognitive Radio (CR) applications. The design is based on the noise-canceling technique, with an indutctorless solution, showing that this technique effectively reduces the noise figure over the desired frequency range with moderate power consumption and a moderate utilization of silicon die area. The wideband LNA covers the frequency range from 50 MHz to 1 GHz, achieving a noise figure below 4dB in over 90% of the band of interest, a gain of 11dB to 12dB, and an input/output return loss higher than -12 dB. The input IIP3 and input P1dB at 580MHz are above 0dB and -10dB, respectively. It consumes 46.5mW from a 1.5V supply and occupies an active area of only 0.056mm2 (0.28mm x 0.2mm).
15

Projeto de um amplificador de baixo ruído em tecnologia CMOS 130nm para frequências de 50MHZ a 1GHz / A 50MHz-1GHz wideband low noise amplifier in 130nm CMOS technology

Pimentel, Henrique Luiz Andrade January 2012 (has links)
O presente trabalho tem por objetivo fornecer o embasamento teórico para o projeto de um amplificador de baixo ruído (LNA – Low Noise Amplifier) em tecnologia CMOS que opere em mais de uma faixa de frequência, de modo a permitir seu uso em receptores multibanda e de banda larga. A base teórica que este trabalho abrange desde a revisão bibliográfica do assunto em questão, passando pela análise dos modelos de transistores para alta-frequência, pelo estudo das especificações deste bloco e das métricas utilizadas em projetos de circuitos integrados de RF, bem como pela revisão de topologias clássicas existentes. Com os conhecimentos acima adquiridos, foi possível realizar o projeto de um LNA diferencial de banda larga utilizando tecnologia CMOS IBM 130nm, o qual pode ser aplicado ao padrão IEEE 802.22 para rádios cognitivos (CR). O projeto é baseado na técnica de cancelamento de ruído, sendo validado após apresentar efetiva redução de figura de ruído para banda de frequência desejada, com moderado consumo de potência e utilização moderada de área de silício, devido a solução sem o uso de indutores. O LNA banda larga opera em frequências de 50Mhz a 1GHz e apresenta uma figura de ruído abaixo de 4dB, em 90% da faixa, um ganho acima de 12dB, e perda de retorno na entrada e na saída maiores que 12dB. O IIP3 e a frequência de ocorrência de compressão a 1dB com a entrada em 580MHz estão acima de 0dBm e -10dBm respectivamente. Possui consumo de 46,5mWpara fonte de 1,5V e ocupa uma área ativa de apenas 0,28mm x 0,2mm. / This work presents the theoretical basis for the design of a low noise amplifier (LNA) in CMOS technology that operates in more than one frequency band, which enables its use in multi-band and wideband receivers. The theoretical basis that this work will address extends from the literature review on the subject, through the analysis of models of MOS transistors for high frequencies, study of specifications of this block and the metrics used in RF integrated circuit design, as well as the review of existing classical LNA topologies. Based on the knowledge acquired above, the design of a differential wideband LNA is developed using IBM 130nm RF CMOS process, which can be used in IEEE 802.22 Cognitive Radio (CR) applications. The design is based on the noise-canceling technique, with an indutctorless solution, showing that this technique effectively reduces the noise figure over the desired frequency range with moderate power consumption and a moderate utilization of silicon die area. The wideband LNA covers the frequency range from 50 MHz to 1 GHz, achieving a noise figure below 4dB in over 90% of the band of interest, a gain of 11dB to 12dB, and an input/output return loss higher than -12 dB. The input IIP3 and input P1dB at 580MHz are above 0dB and -10dB, respectively. It consumes 46.5mW from a 1.5V supply and occupies an active area of only 0.056mm2 (0.28mm x 0.2mm).
16

Projeto de um amplificador de baixo ruído em tecnologia CMOS 130nm para frequências de 50MHZ a 1GHz / A 50MHz-1GHz wideband low noise amplifier in 130nm CMOS technology

Pimentel, Henrique Luiz Andrade January 2012 (has links)
O presente trabalho tem por objetivo fornecer o embasamento teórico para o projeto de um amplificador de baixo ruído (LNA – Low Noise Amplifier) em tecnologia CMOS que opere em mais de uma faixa de frequência, de modo a permitir seu uso em receptores multibanda e de banda larga. A base teórica que este trabalho abrange desde a revisão bibliográfica do assunto em questão, passando pela análise dos modelos de transistores para alta-frequência, pelo estudo das especificações deste bloco e das métricas utilizadas em projetos de circuitos integrados de RF, bem como pela revisão de topologias clássicas existentes. Com os conhecimentos acima adquiridos, foi possível realizar o projeto de um LNA diferencial de banda larga utilizando tecnologia CMOS IBM 130nm, o qual pode ser aplicado ao padrão IEEE 802.22 para rádios cognitivos (CR). O projeto é baseado na técnica de cancelamento de ruído, sendo validado após apresentar efetiva redução de figura de ruído para banda de frequência desejada, com moderado consumo de potência e utilização moderada de área de silício, devido a solução sem o uso de indutores. O LNA banda larga opera em frequências de 50Mhz a 1GHz e apresenta uma figura de ruído abaixo de 4dB, em 90% da faixa, um ganho acima de 12dB, e perda de retorno na entrada e na saída maiores que 12dB. O IIP3 e a frequência de ocorrência de compressão a 1dB com a entrada em 580MHz estão acima de 0dBm e -10dBm respectivamente. Possui consumo de 46,5mWpara fonte de 1,5V e ocupa uma área ativa de apenas 0,28mm x 0,2mm. / This work presents the theoretical basis for the design of a low noise amplifier (LNA) in CMOS technology that operates in more than one frequency band, which enables its use in multi-band and wideband receivers. The theoretical basis that this work will address extends from the literature review on the subject, through the analysis of models of MOS transistors for high frequencies, study of specifications of this block and the metrics used in RF integrated circuit design, as well as the review of existing classical LNA topologies. Based on the knowledge acquired above, the design of a differential wideband LNA is developed using IBM 130nm RF CMOS process, which can be used in IEEE 802.22 Cognitive Radio (CR) applications. The design is based on the noise-canceling technique, with an indutctorless solution, showing that this technique effectively reduces the noise figure over the desired frequency range with moderate power consumption and a moderate utilization of silicon die area. The wideband LNA covers the frequency range from 50 MHz to 1 GHz, achieving a noise figure below 4dB in over 90% of the band of interest, a gain of 11dB to 12dB, and an input/output return loss higher than -12 dB. The input IIP3 and input P1dB at 580MHz are above 0dB and -10dB, respectively. It consumes 46.5mW from a 1.5V supply and occupies an active area of only 0.056mm2 (0.28mm x 0.2mm).
17

CMOS design enhancement techniques for RF receivers : analysis, design and implementation of RF receivers with component enhancement and component reduction for improved sensitivity and reduced cost, using CMOS technology

Logan, Nandi January 2010 (has links)
Silicon CMOS Technology is now the preferred process for low power wireless communication devices, although currently much noisier and slower than comparable processes such as SiGe Bipolar and GaAs technologies. However, due to ever-reducing gate sizes and correspondingly higher speeds, higher Ft CMOS processes are increasingly competitive, especially in low power wireless systems such as Bluetooth, Wireless USB, Wimax, Zigbee and W-CDMA transceivers. With the current 32 nm gate sized devices, speeds of 100 GHz and beyond are well within the horizon for CMOS technology, but at a reduced operational voltage, even with thicker gate oxides as compensation. This thesis investigates newer techniques, both from a systems point of view and at a circuit level, to implement an efficient transceiver design that will produce a more sensitive receiver, overcoming the noise disadvantage of using CMOS Silicon. As a starting point, the overall components and available SoC were investigated, together with their architecture. Two novel techniques were developed during this investigation. The first was a high compression point LNA design giving a lower overall systems noise figure for the receiver. The second was an innovative means of matching circuits with low Q components, which enabled the use of smaller inductors and reduced the attenuation loss of the components, the resulting smaller circuit die size leading to smaller and lower cost commercial radio equipment. Both these techniques have had patents filed by the University. Finally, the overall design was laid out for fabrication, taking into account package constraints and bond-wire effects and other parasitic EMC effects.
18

CMOS design enhancement techniques for RF receivers. Analysis, design and implementation of RF receivers with component enhancement and component reduction for improved sensitivity and reduced cost, using CMOS technology.

Logan, Nandi January 2010 (has links)
Silicon CMOS Technology is now the preferred process for low power wireless communication devices, although currently much noisier and slower than comparable processes such as SiGe Bipolar and GaAs technologies. However, due to ever-reducing gate sizes and correspondingly higher speeds, higher Ft CMOS processes are increasingly competitive, especially in low power wireless systems such as Bluetooth, Wireless USB, Wimax, Zigbee and W-CDMA transceivers. With the current 32 nm gate sized devices, speeds of 100 GHz and beyond are well within the horizon for CMOS technology, but at a reduced operational voltage, even with thicker gate oxides as compensation. This thesis investigates newer techniques, both from a systems point of view and at a circuit level, to implement an efficient transceiver design that will produce a more sensitive receiver, overcoming the noise disadvantage of using CMOS Silicon. As a starting point, the overall components and available SoC were investigated, together with their architecture. Two novel techniques were developed during this investigation. The first was a high compression point LNA design giving a lower overall systems noise figure for the receiver. The second was an innovative means of matching circuits with low Q components, which enabled the use of smaller inductors and reduced the attenuation loss of the components, the resulting smaller circuit die size leading to smaller and lower cost commercial radio equipment. Both these techniques have had patents filed by the University. Finally, the overall design was laid out for fabrication, taking into account package constraints and bond-wire effects and other parasitic EMC effects.
19

Design and reliability of high dynamic range RF building blocks in SOI CMOS and SiGe BiCMOS technologies

Madan, Anuj 11 October 2011 (has links)
The objective of the proposed research is to understand the design and reliability of RF front-end building blocks using SOI CMOS and SiGe BiCMOS technologies for high dynamic-range applications. This research leads to a comprehensive understanding of dynamic range in SOI CMOS devices and contributes to knowledge leading to improvement in overall dynamic range and reliability of RF building blocks. While the performance of CMOS transistors has been improving naturally with scaling, this work aims to explore the possibilities of improvement in RF performance and reliability using standard layouts (that don't need process modifications). The total-ionizing dose tolerance of SOI CMOS devices has been understood with extensive measurements. Furthermore, the role of body contacts in SOI technology is understood for dynamic range performance improvement. In this work, CMOS low-noise amplifier design for high linearity WLAN applications and its integration with RF switch on the same chip is presented. The LNA and switches designed provide state-of-the-art performance in silicon based technologies. Further, the work aims to explore applications of SiGe HBT in the context of highly linear and reliable RF building blocks. The RF reliability of SiGe HBT based RF switches is investigated and compared with CMOS counterparts. The inverse-mode operation of SiGe HBT based switches is understood to give considerably higher linearity.
20

Differential Six-Port Transceiver Design and Analysis from a Wireless Communication System Perspective

Umar, Muhammad, Yasir, Umar January 2012 (has links)
In modern telecommunication there is the demand of high data rates using wideband component design. FCC has introduced the UWB spectrum for high speed data communication. UWB systems have attracted the attention of researchers.  Six-port transmitters and receivers are strong candidates for UWB systems and research is being done on six-port modulators and demodulators. In this work an effort is made to compare the performance of conventional single-ended six-port transmitter and receiver with differential six-port transmitters and receivers.    In this thesis, single ended and differential six-port correlators are designed on 7.5 GHz using Agilent Inc. EDA tool ADS and their performance is evaluated. A new wide-band differential six-port correlator is implemented using rat-race couplers and double-sided parallel strip-line phase inverter. The designed six-port correlators are used for 8-PSK modulation and demodulation. For transmitter-receiver system, mixed analog-DSP designing is used. The integral components of the system are evaluated individually and behavioral modeling is used to evaluate the complete transmitter-receiver system. The single-ended and differential systems are evaluated for noise-figure, dynamic range, bit error rate and data rate.

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