A Wide Tuning-Range mm-Wave LC-VCO Sized Using Evolutionary Algorithms

Designing a LC Voltage Controlled Oscillator (LC-VCO) for mm-Wave frequencies requires a careful balance of interdependent design parameters. The losses due to passive elements dictate the required cross coupled pair transconductance (g m ), which in turn affects the tuning range via fixed capacitance. As such, the design process requires significant engineering time. An optimization methodology using a genetic algorithm is proposed to optimize component selection for use in the LC-VCO. The design for the LC-VCO is broken into pseudo-independent sub-modules to allow the designer greater control and to allow the optimization to benefit from manual circuit intuition. Performance of the components chosen by the genetic algorithm is verified using a circuit simulator to achieve a center frequency of 29 GHz with a 15.8 GHz tuning range. The simulated phase noise performance is -103.2 dBc/Hz using a 10 MHz frequency offset.A one-year embargo was granted for this item.Academic Major: Electrical and Computer Engineerin

High Performance Local Oscillator Design for Next Generation Wireless Communication

Local Oscillator (LO) is an essential building block in modern wireless radios. In modern wireless radios, LO often serves as a reference of the carrier signal to modulate or demod- ulate the outgoing or incoming data. The LO signal should be a clean and stable source, such that the frequency or timing information of the carrier reference can be well-defined. However, as radio architecture evolves, the importance of LO path design has become much more important than before. Of late, many radio architecture innovations have exploited sophisticated LO generation schemes to meet the ever-increasing demands of wireless radio performances. The focus of this thesis is to address challenges in the LO path design for next-generation high performance wireless radios. These challenges include (1) Congested spectrum at low radio frequency (RF) below 5GHz (2) Continuing miniaturization of integrated wireless radio, and (3) Fiber-fast (>10Gb/s) mm-wave wireless communication. The thesis begins with a brief introduction of the aforementioned challenges followed by a discussion of the opportunities projected to overcome these challenges. To address the challenge of congested spectrum at frequency below 5GHz, novel ra- dio architectures such as cognitive radio, software-defined radio, and full-duplex radio have drawn significant research interest. Cognitive radio is a radio architecture that opportunisti- cally utilize the unused spectrum in an environment to maximize spectrum usage efficiency. Energy-efficient spectrum sensing is the key to implementing cognitive radio. To enable energy-efficient spectrum sensing, a fast-hopping frequency synthesizer is an essential build- ing block to swiftly sweep the carrier frequency of the radio across the available spectrum. Chapter 2 of this thesis further highlights the challenges and trade-offs of the current LO gen- eration scheme for possible use in sweeping LO-based spectrum analysis. It follows by intro- duction of the proposed fast-hopping LO architecture, its implementation and measurement results of the validated prototype. Chapter 3 proposes an embedded phase-shifting LO-path design for wideband RF self-interference cancellation for full-duplex radio. It demonstrates a synergistic design between the LO path and signal to perform self-interference cancellation. To address the challenge of continuing miniaturization of integrated wireless radio, ring oscillator-based frequency synthesizer is an attractive candidate due to its compactness. Chapter 4 discussed the difficulty associated with implementing a Phase-Locked Loop (PLL) with ultra-small form-factor. It further proposes the concept sub-sampling PLL with time- based loop filter to address these challenges. A 65nm CMOS prototype and its measurement result are presented for validation of the concept. In shifting from RF to mm-wave frequencies, the performance of wireless communication links is boosted by significant bandwidth and data-rate expansion. However, the demand for data-rate improvement is out-pacing the innovation of radio architectures. A >10Gb/s mm-wave wireless communication at 60GHz is required by emerging applications such as virtual-reality (VR) headsets, inter-rack data transmission at data center, and Ultra-High- Definition (UHD) TV home entertainment systems. Channel-bonding is considered to be a promising technique for achieving >10Gb/s wireless communication at 60GHz. Chapter 5 discusses the fundamental radio implementation challenges associated with channel-bonding for 60GHz wireless communication and the pros and cons of prior arts that attempted to address these challenges. It is followed by a discussion of the proposed 60GHz channel- bonding receiver, which utilizes only a single PLL and enables both contiguous and non- contiguous channel-bonding schemes. Finally, Chapter 6 presents the conclusion of this thesis

Analysis and Design of Radio Frequency Integrated Circuits for Breast Cancer Radar Imaging in CMOS Technology

Breast cancer is by far the most incident tumor among female population. Early stage prevention is a key factor in delivering long term survival of breast cancer patients. X-ray mammography is the most commonly used diagnostic technique to detect non-palpable tumors. However, 10-30% of tumors are missed by mammography and ionizing radiations together with breast compression do not lead to comfort in patient treatment. In this context, ultrawideband microwave radar technology is an attractive alternative. It relies on the dielectric contrast of normal and malignant tissues at microwave frequencies to detect and locate tumors inside the breast. This work presents the analysis and design of radio frequency integrated circuits for breast cancer imaging in CMOS technology. The first part of the thesis concerns the system analysis. A behavioral model of two different transceiver architectures for UWB breast cancer imaging employing a SFCW radar system are presented. A mathematical model of the direct conversion and super heterodyne architectures together with a numerical breast phantom are developed. FDTD simulations data are used to on the behavioral model to investigate the limits of both architectures from a circuit-level point of view. Insight is given into I/Q phase inaccuracies and their impact on the quality of the final reconstructed images. The result is that the simplicity of the direct conversion architecture makes the receiver more robust toward the critical impairments for this application. The second part of the thesis is dedicated to the circuit design. The main achievement is a 65nm CMOS 2-16GHz stepped frequency radar transceiver for medical imaging. The RX features 36dB conversion gain, >29dBm compression point, 7dB noise figure, and 30Hz 1/f noise corner. The TX outputs 14dBm with >40dBc harmonic rejection and <109dBc/Hz phase noise at 1MHz offset. Overall power dissipation is 204mW from 1.2V supply. The radar achieves 3mm resolution within the body, and 107dB dynamic range, a performance enabling the use for breast cancer diagnostic imaging. To further assess the capabilities of the proposed radar, a physical breast phantom was synthesized and two targets mimicking two tumors were buried inside the breast. The targets are clearly identified and correctly located, effectively proving the performance of the designed radar as a possible tool for breast cancer detection

Research for Pseudo Millimeter Wave Circuit Design with 0.18μm CMOS Technology Node

九州工業大学博士学位論文 学位記番号:工博甲第405号 学位授与年月日:平成27年9月25日第一章：イントロダクション | 第二章：技術的課題 | 第三章：モデリング(ディエンベディング)手法 | 第四章：受動素子の設計とそのモデリング結果 | 第五章：K u - バンドの衛星放送受信機用低雑音ブロックに関する研究 | 第六章：K a - バンド周波数変調連続波変調用レーダに適したVCO の研究 | 第七章：結論九州工業大学平成27年