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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.
1

A 0.18µm CMOS UWB wireless transceiver for medical sensing applications

Wang, Xubo 03 September 2008
Recently, there is a new trend of demand of a biomedical device that can continuously monitor patients vital life index such as heart rate variability (HRV) and respiration rate. This desired device would be compact, wearable, wireless, networkable and low-power to enable proactive home monitoring of vital signs. This device should have a radar sensor portion and a wireless communication link all integrated in one small set. The promising technology that can satisfy these requirements is the impulse radio based Ultra-wideband (IR-UWB) technology. Since Federal Communications Commission (FCC) released the 3.1GHz-10.6GHz frequency band for UWB applications in 2002 [1], IR-UWB has received significant attention for applications in target positioning and wireless communications. IR-UWB employs extremely narrow Gaussian monocycle pulses or any other forms of short RF pulses to represent information. <p>In this project, an integrated wireless UWB transceiver for the 3.1GHz-10.6GHz IR-UWB medical sensor was developed in the 0.18µm CMOS technology. This UWB transceiver can be employed for both radar sensing and communication purposes. The transceiver applies the On-Off Keying (OOK) modulation scheme to transmit short Gaussian pulse signals. The transmitter output power level is adjustable. The fully integrated UWB transceiver occupies a core area of 0.752mm^2 and the total die area of 1.274mm^2 with the pad ring inserted. The transceiver was simulated with overall power consumption of 40mW for radar sensing. The receiver is very sensitive to weak signals with a sensitivity of -73.01dBm. The average power of a single pulse is 9.8µW. The pulses are not posing any harm to human tissues. The sensing resolution and the target positioning precision are presumably sufficient for heart movement detection purpose in medical applications. This transceiver can also be used for high speed wireless data communications. The data transmission rate of 200 Mbps was achieved with an overall power consumption of 57mW. A combination of sensing and communications can be used to build a low power sensor.
2

A 0.18µm CMOS UWB wireless transceiver for medical sensing applications

Wang, Xubo 03 September 2008 (has links)
Recently, there is a new trend of demand of a biomedical device that can continuously monitor patients vital life index such as heart rate variability (HRV) and respiration rate. This desired device would be compact, wearable, wireless, networkable and low-power to enable proactive home monitoring of vital signs. This device should have a radar sensor portion and a wireless communication link all integrated in one small set. The promising technology that can satisfy these requirements is the impulse radio based Ultra-wideband (IR-UWB) technology. Since Federal Communications Commission (FCC) released the 3.1GHz-10.6GHz frequency band for UWB applications in 2002 [1], IR-UWB has received significant attention for applications in target positioning and wireless communications. IR-UWB employs extremely narrow Gaussian monocycle pulses or any other forms of short RF pulses to represent information. <p>In this project, an integrated wireless UWB transceiver for the 3.1GHz-10.6GHz IR-UWB medical sensor was developed in the 0.18µm CMOS technology. This UWB transceiver can be employed for both radar sensing and communication purposes. The transceiver applies the On-Off Keying (OOK) modulation scheme to transmit short Gaussian pulse signals. The transmitter output power level is adjustable. The fully integrated UWB transceiver occupies a core area of 0.752mm^2 and the total die area of 1.274mm^2 with the pad ring inserted. The transceiver was simulated with overall power consumption of 40mW for radar sensing. The receiver is very sensitive to weak signals with a sensitivity of -73.01dBm. The average power of a single pulse is 9.8µW. The pulses are not posing any harm to human tissues. The sensing resolution and the target positioning precision are presumably sufficient for heart movement detection purpose in medical applications. This transceiver can also be used for high speed wireless data communications. The data transmission rate of 200 Mbps was achieved with an overall power consumption of 57mW. A combination of sensing and communications can be used to build a low power sensor.
3

The Development of 2.5Gb/s Optical Transceiver Modules

Yang, Jia-neng 30 June 2004 (has links)
In this thesis, the fabrication and performance of the 2.5Gb/s optical transceiver modules applied in optical communication network are discussed. The optical transceiver modules consist of transmitter and receiver. The transmitters are composed by laser driver IC and 1310 FP (Fabry-Perot) laser, where the receivers are composed by limiting amplifier IC and 1310nm ROSA (Receiver Optical Sub-Assembly). In the design of modules, not only components but also the PCB layout affects the performance heavily. In signal transmission, we must use proper termination scheme to eliminate the signal reflection. Besides we must also consider the EMI and crosstalk problems, so the design will be perfect. An optical transceiver module is operated at signal pattern of 27-1 and data rate of 2.5Gb/s. In transceiver, the result of measurement, Peak-Peak Jitter is 29ps. In receiver, back to back, the Peak-Peak Jitter is 29ps. In addition, the measuring result connecting with 2km fiber of Peak-Peak Jitter is 30ps. The result of eye diagram measurement can meet the mask of ITU-T standard. In the condition of bit error rate of 10-12 , the sensitivity of receiver is -15.4dBm.
4

One Channel 10Gb/s Optical transceiver

Chen, Jiun-ming 05 July 2005 (has links)
We fabricate and measure 10Gb/s optical transceiver module for used in optical communication network. The 10Gb/s optical transceiver module consists of a laser, a laser driver IC, a PIN-TIA, a limiting amplifier and a high-frequency print circuit board (PCB) layout design. In the design of modules, the distortion, reflection, the effect of lumped elements and SMA connector are considered. The layout of printed circuit board must be match to the impedance of transmission line. The electromagnetic interference (ISI) issue is also considered in order to achieve the best design of the module. The optical transceiver module is tested at signal pattern of 231-1 and data rate of 10Gb/s. The peak-peak jitter is measured 27ps in transmitter. In receiver, the peak-peak jitter is measured 24ps at back to back. For 10km fiber, the peak-peak jitter is measured 29ps. In the condition of bit error rate (BER) of 10-12, the sensitivity of receiver can reach to -13.5dBm. The result of eye diagram measurement can meet the mask of STM-64/OC-192 standard.
5

Transceiver and Clock Generator for FlexRay-based Automobile Communication Systems

Chen, Po-Cheng 25 June 2008 (has links)
Thanks to the booming of car electronics in recent years, more car electronics devices are installed in ve-hicles. These devices are connected by in-vehicle communication networks. In this thesis, we present the tran-sceiver and clock generator design for the physical layer of a FlexRay-based in-vehicle communication protocol. Regarding the transceiver design, a LVDS-like transmitter is proposed to drive the twisted pair of the bus. By contrast, a 3-comparator scheme is used to carry out the required bit-slicing and state recognition at the re-ceiver end. The reliability and safety are the priority design factors for electronics. A robust 20 MHz clock generator with process, supply voltage, and temperature compensation, a sub-1 MHz oscillator, and a temperature detector are included in our clock generator design. All of these designs are implemented by using a typical 0.18 um single-poly six-metal CMOS process. The proposed prototypical transceiver has been tested by a thermo chamber to justify its operation in the required temperature rage, i.e., -40¢XC to 125¢XC. Moreover, the compatibility of our design is also verified in a real FlexRay-based network. The maximum throughput of the proposed prototypical transceiver can reach 40 Mbps.
6

Bidirectional Transceiver Modules on the Silicon Bench for WDM applications

Wang, Jyun-Ying 24 June 2009 (has links)
The primary target of this paper is to fabricate bidirectional transceiver modules based on Si-bench technology. The bidirectional transceiver modules were formed by hybrid integration of single mode lens fibers and ultra-thin thin-film filters (TFF) on silicon bench as using V-groove and U-groove techniques. The output light at 1.31 £gm was launched into the input lens fiber of the module. After passing through the TFF, the light was received by the output lens fiber of the module. The insertion loss of the module at the 1.31 £gm light was -0.68 dB. On the other hand, incoming lights at 1.49£gm and 1.55£gm were received from the output lens fiber. Lights at 1.49£gm will pass through the filter, and was received by the output lens fiber of the module. The insertion loss of the module at the 1.49 £gm light was -0.65 dB. The 1.55£gm wavelength lights received from the lens fiber are reflected by the filter and collected by the multimode fiber to the photo diode. The insertion loss of the module at the 1.55 £gm light was -0.58 dB.
7

Ultra-Wideband CMOS Transceiver Front-End for Bio-Medical Radar Sensing

2013 November 1900 (has links)
Since the Federal Communication Commission released the unlicensed 3.1-10.6 GHz frequency band for commercial use in early 2002, the ultra wideband (UWB) has developed from an emerging technology into a mainstream research area. The UWB technology, which utilizes wide spectrum, opens a new era of possibility for practical applications in radar sensing, one of which is the human vital sign monitoring. The aim of this thesis is to study and research the possibility of a new generation humanrespiration monitoring sensor using UWB radar technology and to develop a new prototype of UWB radar sensor for system-on-chip solutions in CMOS technology. In this thesis, a lowpower Gaussian impulse UWB mono-static radar transceiver architecture is presented. The UWB Gaussian pulse transmitter and receiver are implemented and fabricated using 90nm CMOS technology. Since the energy of low order Gaussian pulse is mostly condensed at lower frequency, in order to transmit the pulse in a very efficient way, higher order Gaussian derivative pulses are desired as the baseband signal. This motivates the advancement of the design into UWB high-order pulse transmitter. Both the Gaussian impulse UWB transmitter and Gaussian higher-order impulse UWB transmitter take the low-power and high-speed advantage of digital circuit to generate different waveforms. The measurement results are analyzed and discussed. This thesis also presents a low-power UWB mono-static radar transceiver architecture exploiting the full benefit of UWB bandwidth in radar sensing applications. The transceiver includes a full UWB band transmitter, an UWB receiver front-end, and an on-chip diplexer. The non-coherent UWB transmitter generates pulse modulated baseband signals at different carrier frequencies within the designated 3-10 GHz band using a digitally controlled pulse generator. The test shows the proposed radar transceiver can detect the human respiration pattern within 50 cm distance. The applications of this UWB radar sensing solution in commercialized standard CMOS technology include constant breathing pattern monitoring for gated radiation therapy, realtime monitoring of patients, and any other breathing monitoring. The research paves the way to wireless technology integration with health care and bio-sensor network.
8

Spectral PLL Built-In Self-Test for integrated cellular transmitters = Spektraler PLL-Selbsttest für integrierte Mobilfunktransmitter

Münker, Christian January 2010 (has links)
Zugl.: Erlangen-Nürnberg, Univ., Diss., 2010.
9

2GHz W-CDMA Radio Transceiver

Cheung, Tze Chiu 06 January 1999 (has links)
A radio transceiver has been designed and built for a W-CDMA experimental system operating at 2GHz. The radio is an RF front-end for mobile terminals. The radio provides the functions of modulation and demodulation to enable transmitting and receiving digital information through the air link. The radio comprises one transmitter in conjunction with transmit power control (TPC), two independent receivers in conjunction with automatic gain control (AGC) and automatic frequency control (AFC), and one common synthesizer. Data exchange between the radio and the baseband processor takes place in an 8-bit digital format. Digital-to-analog converters (DAC) at the transmitter and analog- to-digital converters (ADC) at the receivers provide the interface between the radio and the baseband processor. DACs are also used to convert the 7-bit command codes from the processor to analog signals for the TPC, AGC and AFC. The radio transceiver is designed to meet the stringent requirements imposed by the W-CDMA system. The 70dB TPC enables the adaptive power control for combating the near-far problem. The high linearity of the transmitter provides the use of linear modulation with less than 40dBc adjacent channel power suppression. The 0.03125ppm tuning resolution of the AFC maximizes the receiver sensitivity. The 80dB AGC produces a constant demodulated signal level to the ADC regardless of the RF signal level. This thesis documents the design methodology for this radio transceiver. / Master of Science
10

The Study of Electromagnetic Shielding Employing Woven Continuous Carbon Fiber Composites for 2.5Gb/s Transceiver Modules

Lee, Chien-hui 03 July 2004 (has links)
A High electromagnetic shielding, light weight, low cost plastic package is developed by using a woven continuous carbon fiber (WCCF) epoxy composite. Three different weaving types of WCCF, plain¡Bbalanced twill and uni-direction structure, are fabricated for understanding the shielding property of the WCCF composites. By weaving the WCCF in a balanced twill structure with excellent conductive network, it shows that the SE can reach to about 80dB under plane-wave source measurement and about 50dB in the near-field source measurement. By comparison of cost, weight, and shielding performance for optical transceiver modules fabricated by the housings of woven continuous carbon fiber, nanoscale hollow carbon nanocapulses (HCNCs) epoxy composites and nylon and liquid crystal polymer (LCP) with carbon fiber filler composite, the WCCF composites shows lower cost, light weight, and higher electromagnetic shielding than the other types of composites.

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