Biography
Enrollment Date: 2011
Graduation Date：2014
Degree：M.S.
Defense Date：2014.05.26
Advisors：Woogeun Rhee
Department：Institute of Microelectronics，Tsinghua University
Title of Dissertation/Thesis：Impulse-Radio Ultra-Wideband Transceivers for Low-Power Short-Range High-Data-Rate Wireless Communication
Abstract:
Recently, as the rapid development in smart electronics devices, not only the academia but also the industrial has paid great attention on the short-range wireless communications. Transceivers based on Wireless Body Area Network (WBAN) or Wireless Person Area Network (WPAN) standards have been widely used in fields of consumer electronics, advanced medical equipment and industrial electronics. Such a wide range of potential application also posed great challenges.
UWB technology features ultra wide frequency band and extremely low emission power. Compared to other narrow band systems, these are unique advantages. As large as more than 7GHz frequency band can provide flexible data rate ranging from Kb/s to Gb/s. Also the frequency can be reused due to the low emission power. Of all the UWB technologies, impulse-radio UWB map the data into very short pulses, which can support various modulation schemes, such as On-off keying, only when binary data “1” is transmitted pulses will be triggered, which renders the extremely low duty-cycled operation for transceiver. Against the coherent demodulation scheme, non-coherent methods, like energy detection can have very low system complexity and power consumption, which results in a very high energy-efficiency.
This work mainly focuses on very high speed short range wireless transceiver design based on OOK modulation and energy-detection demodulation strategy. Typical issues with high data rate IR-UWB systems are analyzed, then both system and circuit level considerations are explained in detail.
To overcome the limited pulse peak power and communication range for high PRF transmission, a frequency hopping technology is used to increase the pulse energy and extend the range for high data rate IR-UWB systems. With no additional hardware expense, capability of channel estimation for multi-band IR-UWB systems is explored with the band-switching RF amplifiers.
To suppress the narrow band interference from knowledgeable radios, a notching filtering low noise amplifier is proposed. The notching filtering network embedded in the amplifiers is implemented with bonding wire inductance. Also, in order to estimate the optimized energy threshold for the energy-detection receivers, an original energy integrating as well as sampling method is invented. Through the proposed energy detection, closed loops of auto gain control and phase synchronization are also obtained.
To verify the function of the proposed transceiver, an energy detection receiver with the proposed channel estimation capability and another IR-UWB transceiver with Gb/s data rate for tens of centimeters range are implemented in TSMC65nm CMOS process.