A Dual-mode Wide-band CMOS Oscillator for Millimeter-wave Applications

A Dual-mode Wide-band CMOS Oscillator for Millimeter-wave Applications
Author: Shatam Agarwal
Publisher:
Total Pages: 78
Release: 2010
Genre:
ISBN:

Broadband voltage-controlled oscillators are critical to the design of millimeter wave frequency synthesizers. This thesis proposes a design technique that can be used to significantly extend the achievable frequency span of an oscillator. A dual-band oscillator topology is described that can be configured to operate in one of two modes, by an electrical reconfiguration of the negative resistance core around the resonant tank, without switching passive elements within the tank itself. The configuration helps to minimize the difference in phase noise performance between the two modes, while achieving a wide tuning range. To verify the concept, a mm-wave VCO that operates at 30-GHz is designed in a commercial 0.18-um CMOS technology, with an approximate simulated tuning range of 20%. A dual-mode oscillator is also designed in a 0.13-um technology at 60-GHz.

Application of Dual-Mode Wide-Band CMOS Oscillators

Application of Dual-Mode Wide-Band CMOS Oscillators
Author: Abdolhossein Ayoubi
Publisher: CreateSpace
Total Pages: 78
Release: 2015-07-21
Genre:
ISBN: 9781515167266

Broadband voltage-controlled oscillators are critical to the design of millimeter wave frequency synthesizers. This book proposes a design technique that can be used to significantly extend the achievable frequency span of an oscillator. A dual-band oscillator topology is described that can be configured to operate in one of two modes, by an electrical reconfiguration of the negative resistance core around the resonant tank, without switching passive elements within the tank itself. The configuration helps to minimize the difference in phase noise performance between the two modes, while achieving a wide tuning range. This book includes five chapters and through these chapters the necessary information for designing millimeter wave frequency synthesizers are provided for the readers.

Design of Digital Phase Shifters for Multipurpose Communication Systems

Design of Digital Phase Shifters for Multipurpose Communication Systems
Author: Binboga Siddik Yarman
Publisher: CRC Press
Total Pages: 557
Release: 2022-09-01
Genre: Technology & Engineering
ISBN: 1000795527

Design of Digital Phase Shifters for Multipurpose Communication Systems aims to cover a new emerging need in designing digital phase shifters for modern communication systems. With the advancement of new generation mobile communication systems, directed beams save a substantial amount of RF-power, and improve the noise immunity. In this regard, beam-forming circuits, namely, digital phase shifters constitute essential parts the antenna arrays. Therefore, this book is devoted to design of digital phase shifters for various communications systems. In the good old days, phase shifter design requirements used to demand narrow bandwidth with no physical size constraints. Nowadays, they must be compact and suitable for Very Large Scale Integrated Circuits (VLSI) or Microwave Monolithic Integrated Circuit (MMIC) implementation with Wide Phase Range (WPR) and Wide Frequency Band (WFB). Since the 1980s, the author has been designing digital phase shifters for various applications. He started to work with loaded lines phase shifters, and then employed branch line couplers to achieve wider frequency bands. In order to reduce the physical size, he used a 3 element Symmetric LC ladder based T or PI configurations. In order to achieve broad frequency band with large phase range, usage of LC lattice structures is inevitable. Lately, the author designed phase shifters using both lowpass and highpass LC ladder and lattice based switched-structures, which are suitable for monolithic implementation. In the course of design, MOS transistors were employed as switching elements. This book includes several novel digital phase shifter topologies, which provides wide phase range and wideband operation. Technical topics discussed in the book include:- Basic Concept of Antenna Arrays- Concept of Digital Phase Bit- Scattering Parameters to analyze the electric performance of phase shifters- Transmission Lines as circuit elements to construct practical phase shifters- Loaded Line Digital Phase Shifters (DPS)- Lowpass Based T/PI Section DPS- Highpass Based T/PI Section DPS- 3-Element LC T/PI Section DPS- Wide Phase Range, Wide Frequency Band Symmetric Lattice Based DPS For each topology presented, explicit design equations are provided and programs to assess the electric performance of each topology is developed in a MatLab environment. It is expected that the reader will be self-sufficient to design and implement the digital phase shifters topologies presented in this book.

Reconfigurable Dual-mode Voltage-controlled Oscillator and Wideband Frequency Synthesizer for Millimeter-wave Applications

Reconfigurable Dual-mode Voltage-controlled Oscillator and Wideband Frequency Synthesizer for Millimeter-wave Applications
Author: Cheng-Hsien Hung
Publisher:
Total Pages: 260
Release: 2015
Genre:
ISBN:

Demands for high data-rate communications and high-precision sensing applications have pushed wireless systems towards higher operating frequencies where wider bandwidth is available. Examples of such applications include 60 GHz indoor communications and vehicular RADAR around 77 GHz. High-speed frequency synthesizers integrated in a CMOS process, with wide operating bandwidth, and low phase noise are key to low-cost transceiver implementations for such applications. The requirement to operate over a wide span of carrier frequencies arises from two key sources. The system itself often requires a wide tuning range, in excess of 5-10% of the carrier frequency. Further, it is necessary to compensate for the uncertainty in operating frequencies, caused by process and temperature variations. This dissertation introduces a dual-mode voltage-controlled oscillator (VCO) topology, embedded in a frequency synthesizer, for wideband operation. The VCO can operate in two oscillation modes by reconfiguring the active negative resistance core around the LC tank that is employed as the resonator element in the oscillator. A key aspect to the design is that the switches used for mode reconfiguration do not contribute to the tank loss. The frequency spacing of the two modes is determined by an accurate inductor ratio. It is demonstrated through analysis that in order to ensure mode-switching, the size of the switches needs be larger than a critical value, which is a function of the electrical properties of the cross-coupled, negative resistance core, as well as the resonator used in the design. The impact of noise injection and mismatch on switching behavior is also analyzed. The VCO topology has been implemented in a 65nm CMOS process. The design demonstrates measured tuning ranges of 56.9 GHz to 65.4 GHz, and 64.6 GHz to 75.3 GHz, in the two respective modes, for a total effective tuning range of 28%. The oscillator consumes 13 mW, with a 1 V-supply, and its Figure of Merit with tuning range (FOM[subscript T]) is -177.2 dB. An integer-N frequency synthesizer that employs the dual-mode VCO, has also been designed and verified in a 65 nm CMOS process. The synthesizer has a locking range from 56 GHz to 63.9 GHz in its low frequency mode. The total power consumption of the synthesizer, including output buffers, is approximately 50 mW. The in-band phase noise, at a locked frequency of 63.04 GHz, is -88.4 dBc/Hz at 1 MHz offset.

Transactions

Transactions
Author: Institute of Electrical and Electronics Engineers
Publisher:
Total Pages: 52
Release: 1962
Genre:
ISBN:

Multiphase Reference Signal Generation Using Coupled Oscillators

Multiphase Reference Signal Generation Using Coupled Oscillators
Author: Mohammad Hekmat
Publisher: Stanford University
Total Pages: 132
Release: 2011
Genre:
ISBN:

The continuing trend toward higher frequencies of operation poses formidable challenges in the design of multiphase reference signals at mm-wave frequencies and beyond. Conventional multiphase reference generation techniques face serious implementation or performance challenges when scaled to microwave and mm-wave frequencies. Ring oscillators suffer from poor phase noise, and hence fail to fulfill the stringent requirements of most wireless applications. Generating multiphase signals by dividing the output of an oscillator operating at multiples of the intended frequency of operation is impractical when frequencies approach the mm-wave range. Cross-coupled LC oscillators have been explored as a promising alternative for multiphase and, in particular, quadrature generation. However, the frequency ambiguity that results from multiple modes of operation, as well as the severe phase noise degradation due to their inherent off-resonance operation, has inhibited their utilization in practice. This work introduces a new topology for coupled oscillators that solves the frequency ambiguity issue and mitigates phase noise degradation in coupled oscillators by employing an array of LC oscillators that are coupled in a bidirectional fashion. The proposed bidirectional coupling enforces operation at the resonance frequency of the LC tanks of the oscillator in the loop, a property that proves to be key in solving both the aforementioned issues. A quadrature frequency doubling topology using bidirectionally-coupled oscillators is also presented. The proposed approach relaxes the linearity requirements on the mixers employed in the circuit, thus allowing the frequency doubler to use highly nonlinear mixers. An experimental prototype integrated in a 90-nm CMOS technology provides output phases in increments of 45 degrees and achieves a phase noise of −101 dBc/Hz at 1- MHz offset from a 19.6-GHz carrier. The quadrature 40-GHz signal generated on chip drives a single-sideband transmitter that achieves a sideband suppression of better than 45 dB.

Design of Mm-wave Reflection-Type Phase Shifters with Oscillation-Based Test Capabilities

Design of Mm-wave Reflection-Type Phase Shifters with Oscillation-Based Test Capabilities
Author: Marc Margalef rovira
Publisher:
Total Pages: 0
Release: 2020
Genre:
ISBN:

This work focuses on the design of on-silicon mm-wave Reflection-Type Phase Shifters (RTPS) with Oscillation-Based Test (OBT) capabilities. For more consistency, a single technology was considered, the STM 55-nm BiCMOS. First, the theory and practical implementations of 3-dB couplers is discussed. Particular attention is brought to the Coupled Slow-wave CoPlanar Waveguide (CS-CPW) topology, due to its good performance. Using this topology, the measurements of two 3-dB couplers are reported: (i) a 120-GHz, and (ii) a 185-GHz coupler.Next, the existing topologies of integrated varactors are discussed. Measurement results are reported for an Inversion-mode MOS (I-MOS) varactor from 1 up to 325 GHz. Additionally, the Common-Source MOS (CS-MOS) varactor architecture is proposed and measurement results from 1 to 145 GHz for this architecture are reported.Then, the theory of RTPS is presented and CS-CPW-based couplers together with Accumulation-mode MOS (A-MOS), I-MOS and CS-MOS varactors are used for the design of four RTPS. The measurement and simulation results of these RTPS, with central frequencies ranging from 60 to 200 GHz, are presented.Subsequently, the theory and measurement results of the OBT on an integrated 60-GHz RTPS are discussed.Finally, a mm-wave TRL calibration compaction technique is described using machine-learning tools.