Reconfigurable RF and Wireless Architectures Using Ultra-stable Micro- and Nano-electromechanical Oscillators: Emerging Devices, Circuits, and Systems
General Material Designation
[Thesis]
First Statement of Responsibility
Islam, Mohammad Saiful
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
Case Western Reserve University
Date of Publication, Distribution, etc.
2020
GENERAL NOTES
Text of Note
327 p.
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
Ph.D.
Body granting the degree
Case Western Reserve University
Text preceding or following the note
2020
SUMMARY OR ABSTRACT
Text of Note
The pervasive Internet of Thing (IoT) revolution is driving the need for fundamental innovations in sensing, electronics, and ubiquitous computing that enable scalable, miniaturized, secure, and energy-efficient devices and networks. Due to some exceptional properties (such as small form factors, low phase noise thanks to ultra-high quality factor (Q), low power consumption, robustness to shock and vibration, amenability to monolithic integration with standard CMOS technology, compatibility with batch manufacturing, and wide operating temperature range), stable and self-sustained oscillators enabled by micro- and nano-electromechanical systems (MEMS and NEMS) devices have a myriad of applications including Internet of Things/Everything (IoTs/E) sensor nodes, next-generation wireless transceivers, RF signal processors, precision sensors, and navigation systems (e.g., GNSS). This dissertation focuses on ultra-stable MEMS-referenced oscillators for such applications. It describes the design, simulation, and experimental verification of three generations of digitally-programmable single-chip application-specific-integrated-circuits (ASICs) that can be integrated with MEMS and NEMS resonators to generate stable reference oscillators in the 10 kHz-16 MHz frequency range. We have also shown various functionalities of these amplifiers, including adaptive control of input impedance, automatic level control (ALC), automatic cancellation of parasitic electrical feedthrough in order to increase the signal to background ratio (SBR), optimizing the trade-off between tunability and stability, parametric pumping, frequency-locked loop (FLL) to stabilize the output frequency, and phase-controlled-closed-loop (PCCL) operation to find the optimal operating point. The chips have been used to realize i) ̴ 7 MHz ultra-stable (-105 dBc/Hz @ δf = 10 Hz) single and quadrature oscillators based on an ultra-high-Q ( ̴ 3.2 × 106 at Vp = 35V) wafer-level vacuum-encapsulated single-crystal-silicon (SCS) Lamé-mode MEMS resonator; and ii) a 10 MHz GPS-disciplined reference oscillator (GPSDO) using a dual-ring breath-mode MEMS resonator. An oven controlled and a real-time software controlled active temperature compensation loop improves the Lamé-mode oscillator's frequency stability down to ± 0.5 ppm with an Allan deviation (ADEV) of 1×10-8 at 103 s. Two of these oscillators were electrically coupled to realize a mutually-coupled-injection-locked low-phase-noise quadrature-referenced oscillator which is suitable for complex-domain PLLs. The short-term stability of both oscillators were optimized using a PCCL algorithm, and the 10 MHz oscillator was injection-locked to a GPSDO steering signal to improve long-term stability. Finally, various advanced features of the oscillators were explored such as: i) real-time tracking of maximum stability points (MSPs) in order to adaptively minimize phase noise or ADEV; ii) ability to realize multi-phase injection-locked oscillator arrays; and iii) ability to connect multiple chips in parallel in order to explore the physics of mode coupling and power handling capability in multimode MEMS resonators.