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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

Integrating a Limiter/Filter/Amplifier into a Conformal Wraparound GPS/TM Antenna Substrate

Ryken, Marv, Davis, Rick, Kujiraoka, Scott 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Missile instrumentation systems designers are constantly striving to achieve better performance out of their systems. Optimizing the antenna coverage and decreasing the noise figure are constantly strived for in order to improve system performance. At the same time, weapon systems are becoming smaller with the resulting reduced area for instrumentation. One way to achieve a lower system noise figure is to have the limiter, filter, and amplifier (LFA) located as close to the antenna as possible. This can be achieved by integrating the LFA into the substrate of a conformal wraparound antenna. Not only does this decrease the system noise, but it also saves space in an already crowded missile instrumentation section. This paper details the latest efforts in accomplishing this integration.
12

New Developments in Integrated Airborne Antennas

Ryken, Marv 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / New developments in miniaturized integrated film bulk acoustic resonator (FBAR) filters and low noise amplifiers have resulted in the possibility of extremely small integrated antenna, filter, and low noise amplifier subsystems for use in airborne telemetry (TM) systems. This paper gives examples of a new development in airborne GPS antennas using an integrated band pass FBAR filter and low noise amplifier. Data is also included on the example antenna in a GPS/TM system.
13

Broadband Low-Noise CMOS Mixers For Wireless Communications

Jiang, FAN 03 October 2013 (has links)
In this thesis, three broadband low-noise mixing circuits which use CMOS 130 nm technology are presented. As one of the first few stages in a receiving front-end, stringent requirements are posted on mixer performance. The Gilbert cell mixers have presented excellent properties and achieved wide applications. However, the noise of a conventional active Gilbert cell mixer is high. This thesis demonstrates both passive and active mixing circuits with improved noise performance while maintaining the advantages of the Gilbert cell-based mixing core. Furthermore, wide bandwidth and variable gain are implemented, making the designed mixers multi-functional, yet with compact sizes and low power consumptions. The first circuit is a passive 2x subharmonic mixer that works from 4.5 GHz to 8.5 GHz. The subharmonic mixing core is a two-stage passive Gilbert cell driven by a quadrature LO signal. Together with a noise-cancelling transconductor and an inverter-based TIA, this subharmonic mixer possesses an excellent broadband conversion gain and a low noise figure. Measurement results show a high conversion gain of 16 dB and a low average DSB NF of 9 dB. The second design is a broadband low-noise variable gain mixer which operates between 1 and 6 GHz. The transconductor stage is implemented with noise cancellation and current bleeding techniques. Series inductive peaking is used to extend the bandwidth. Gain variation is achieved by a current-steering IF stage. Measurements show a wide gain control range of 13 dB and a low noise performance over the entire frequency and gain range. The lowest DSB NF is 3.8 dB and the highest DSB NF is 14.2 dB. The Third design is a broadband low-noise mixer with linear-in-dB gain control scheme. Using the same transconductance stage with the second circuit, this design also works from 1 to 6 GHz. A 10 dB linear-in-dB gain control range is achieved using an R-r load network with a linear-in-dB error less than $\pm$ 0.5 dB. Low noise performance is achieved. For different frequencies and conversion gains, the lowest DSB NF is 3.8 dB and the highest DSB NF is 12 dB. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2013-10-02 04:37:31.606
14

RF Front-End Heterogeneous Chip Integration and the Use of Magnetically Coupled Interconnection Techniques

Lee, Cheng-Tse 19 July 2011 (has links)
The first part of this thesis studies the wire-bonding technology for use in an integrated design of transformer balun and RF front-end receiver, which is realized by IPD and CMOS technology, respectively. In this part, the RF front-end receiver and the balun were designed separately, and the bondwire model was established based on electromagnetic simulation. For the maximum power transfer and optimal noise performance, the input impedance between the CMOS RF front-end receiver and the IPD balun was conjugate-matched. The IPD balun, placed in front of the differential LNA of a direct-conversion receiver, is designed using the IPD technology, thereby reducing the insertion loss, and subsequently improving the noise figure of the CMOS receiver. The second part of this thesis uses a vertically coupled transformer balun with a primary coil made by IPD technology and a secondary coil made by CMOS technology. This balun has a low-loss advantage when integrated with a posterior differential LNA. Finally, the magnetic resonance coupling for use in signal transmission is studied and experimented on a printed circuit board.
15

High performance building blocks for wireless receiver: multi-stage amplifiers and low noise amplifiers

Fan, Xiaohua 15 May 2009 (has links)
Different wireless communication systems utilizing different standards and for multiple applications have penetrated the normal people's life, such as Cell phone, Wireless LAN, Bluetooth, Ultra wideband (UWB) and WiMAX systems. The wireless receiver normally serves as the primary part of the system, which heavily influences the system performance. This research concentrates on the designs of several important blocks of the receiver; multi-stage amplifier and low noise amplifier. Two novel multi-stage amplifier typologies are proposed to improve the bandwidth and reduce the silicon area for the application where a large capacitive load exists. They were designed using AMI 0.5 m µ CMOS technology. The simulation and measurement results show they have the best Figure-of-Merits (FOMs) in terms of small signal and large signal performances, with 4.6MHz and 9MHz bandwidth while consuming 0.38mW and 0.4mW power from a 2V power supply. Two Low Noise Amplifiers (LNAs) are proposed, with one designed for narrowband application and the other for UWB application. A noise reduction technique is proposed for the differential cascode Common Source LNA (CS-LNA), which reduces the LNA Noise Figure (NF), increases the LNA gain, and improves the LNA linearity. At the same time, a novel Common Gate LNA (CG-LNA) is proposed for UWB application, which has better linearity, lower power consumption, and reasonable noise performance. Finally a novel practical current injection built-in-test (BIT) technique is proposed for the RF Front-end circuits. If the off-chip component Lg and Rs values are well controlled, the proposed technique can estimate the voltage gain of the LNA with less than 1dB (8%) error.
16

Development and validation of a low noise signal acquisition protocol for inner ear evoked potentials

Kumaragamage, Chathura Lahiru 07 1900 (has links)
A low noise signal acquisition protocol is required for inner ear evoked response recordings. In this work, a parallel amplifier approach was investigated to implement a bio-signal amplifier with low voltage noise (<5nV/√Hz), and low current noise (~2fA/√Hz). A modified ear electrode was investigated to reduce biological interference and thermal noise due to high impedance electrodes. A physical model to simulate electrical activity of the inner ear was developed to evaluate the accuracy of detecting vestibular field potentials (FPs) in the presence of various noise sources. Muscle activity and noise generated from the recording apparatus were found to be the dominating sources, degrading performance of FP extraction. Contributions from this work include: the design, implementation, and validation of a bio-signal amplifier with <5nV/√Hz voltage noise, and a low impedance electrode development and placement protocol. As a result, a signal-to-noise-ratio improvement of ~11dB (compared to the current protocol) was achieved.
17

Development and validation of a low noise signal acquisition protocol for inner ear evoked potentials

Kumaragamage, Chathura Lahiru 07 1900 (has links)
A low noise signal acquisition protocol is required for inner ear evoked response recordings. In this work, a parallel amplifier approach was investigated to implement a bio-signal amplifier with low voltage noise (<5nV/√Hz), and low current noise (~2fA/√Hz). A modified ear electrode was investigated to reduce biological interference and thermal noise due to high impedance electrodes. A physical model to simulate electrical activity of the inner ear was developed to evaluate the accuracy of detecting vestibular field potentials (FPs) in the presence of various noise sources. Muscle activity and noise generated from the recording apparatus were found to be the dominating sources, degrading performance of FP extraction. Contributions from this work include: the design, implementation, and validation of a bio-signal amplifier with <5nV/√Hz voltage noise, and a low impedance electrode development and placement protocol. As a result, a signal-to-noise-ratio improvement of ~11dB (compared to the current protocol) was achieved.
18

Construction of a Low-Noise Amplifier Chain With Programmable Gain and Offset

Tallhage, Jonas January 2013 (has links)
A low-noise, variable gain amplier chain was constructed for interfa-cing a sensor to an ADC. During the course of the work two dierent methods -switched-capacitor circuits and chopping circuits - for dealing with 1/f noise wereinvestigated during the course of the work. The resulting circuit did not quitemeet the performance required by the specication, some possible improvementsare suggested.
19

Σχεδιασμός και υλοποίηση ενισχυτή υψηλών συχνοτήτων πολύ χαμηλού θορύβου για ραδιοτηλεσκόπιο

Σαρρής, Γεώργιος 19 October 2012 (has links)
Στην εργασία αυτή περιγράφεται η διαδικασία σχεδίασης ενός ενισχυτή χαμηλού θορύβου, ο οποίος αποτελεί το πιο κρίσιμο κομμάτι ενός δέκτη υψηλών συχνοτήτων όσον αφορά τη θορυβική συμπεριφορά. Η μέθοδος εφαρμόζεται στη σχεδίαση ενός ενισχυτή χαμηλού θορύβου στη συχνότητα των 1.42 GHz, ο οποίος θα αποτελέσει το πρώτο στάδιο του δέκτη ενός ραδιοτηλεσκόπιου. Τέλος σχεδιάζεται η πλακέτα πάνω στην οποία υλοποιείται ο ενισχυτής και παρουσιάζονται τεχνικές μέτρησης πολύ χαμηλού θορύβου. / In this thesis a methodology for the design of a Low Noise Amplifier is described. This amplifier consists the most critical part of a Radio Frequency receiver regarding the noise performance. The method is applied to the design of a low noise amplifier at the frequency of 1.42GHz, which will be the first stage of a radio telescope receiver. At the end, the printed circuit board of the amplifier is designed and very low noise measurement techniques are presented.
20

Anténa s nízkošumovým zesilovačem pro pásmo VHF / VHF-band antenna and low-noise amplifier

Bauer, Tomáš January 2009 (has links)
The contents of this thesis is a realization of a low noise amplifier for the band from 137MHz to 138MHz and a antenna for the recieving of the signal from NOAA satellites. The proper function of the low niose amplifier is verified by Ansoft Desinger simulation and the proper function of the antenna is verified by HFSS simulation. Both devices are realizated like prototypes and their parametres are measured.

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