Superregeneration revisited: from principles to current applications

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Wireless communications play a central role in our modern connected lives; at the same time, they constitute a very broad and deep area of research. The elements that make wireless communications possible are a transmitter, which sends information through electromagnetic waves; a medium that is able to transport these waves; and, finally, a receiver, which extracts the information from the-usually very small-amount of energy it is able to collect from the medium.Peer ReviewedPostprint (author's final draft

Millimeter-Wave Super-Regenerative Receivers for Wireless Communication and Radar

Today’s world is becoming increasingly automated and interconnected with billions of smart devices coming online, leading to a steep rise in energy consumption from small microelectronics. This coincides with an urgent push to transform global energy production to green energies, causing disruptions and energy shortages, and making the case for efficient energy use ever more pressing. Two major areas where high growth is expected are the fields of wireless communication and radar sensors. Millimeter-wave frequency bands are planned for fifth-generation (5G) and sixth-generation (6G) cellular communication standards, as well as automotive frequency-modulated continuous wave (FMCW) radar systems for driving assistance and automation. Fast silicon-based technologies enable these advances by operating at high maximum frequencies, such as the silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technologies. However, even the fastest transistors suffer from low and energy expensive gains at millimeter-wave frequencies. Rather than incremental improvements in circuit efficiency using conventional approaches, a disruptive revolution for green microelectronics could be enabled by exploring the low-power benefits of the super-regenerative receiver for some applications. The super-regenerative receiver uses a regenerative oscillator circuit to increase the gain by positive feedback, through coupling energy from the output back into the input. Careful bias and control of the circuit enables a very large gain from a small number of transistors and a very low energy dissipation. Thus, the super-regenerative oscillator could be used to replace amplifier circuits in high data rate wireless communication systems, or as active reflectors to increase the range of FMCW radar systems, greatly reducing the power consumption. The work in this thesis presents fundamental scientific research into the topic of energy-efficient millimeter-wave super-regenerative receivers for use in civilian wireless communication and radar applications. This research work covers the theory, analysis, and simulations, all the way up to the proof of concept, hardware realization, and experimental characterization. Analysis and modeling of regenerative oscillator circuits is presented and used to improve the understanding of the circuit operation, as well as design goals according to the specific application needs. Integrated circuits are investigated and characterized as a proof of concept for a high data rate wireless communication system operating between 140–220 GHz, and an automotive radar system operating at 60 GHz. Amplitude and phase regeneration capabilities for complex modulation are investigated, and principles for spectrum characterization are derived. The circuits are designed and fabricated in a 130 nm SiGe HBT technology, combining bipolar and complementary metal-oxide semiconductor (BiCMOS) transistors. To prove the feasibility of the research concepts, the work achieves a wireless communication link at 16 Gbit/s over 20 cm distance with quadrature amplitude modulation (QAM), which is a world record for the highest data rate ever reported in super-regenerative circuits. This was powered by a super-regenerative oscillator circuit operating at 180 GHz and providing 58 dB of gain. Energy efficiency is also considerably high, drawing 8.8 mW of dc power consumption, which corresponds to a highly efficient 0.6 pJ/bit. Packaging and module integration innovations were implemented for the system experiments, and additional broadband circuits were investigated to generate custom quench waveforms to further enhance the data rate. For radar active reflectors, a regenerative gain of 80 dB is achieved at 60 GHz from a single circuit, which is the best in its frequency range, despite a low dc power consumption of 25 mW

Récepteur Sans-Fil à Basse Consommation et à Modulation Mixte FSK-ASK pour les Dispositifs Médicaux

RÉSUMÉ Les émetteurs-récepteurs radiofréquences (RF) offrent le lien de communications le plus commun afin de mettre au point des dispositifs médicaux implantables dédiés aux interfaces homme-machines. La surveillance en continu des paramètres biologiques des patients nécessite un module de communication sans-fil capable de garantir un échange de données rapide, en temps réel, à faible puissance tout en étant implémenté dans un espace physique réduit. La consommation de puissance des dispositifs implantables joue un rôle important dans les durées de vie des batteries qui nécessitent une chirurgie pour leur remplacement, à moins qu’une technique de transfert de puissance sans-fil soit utilisée pour recharger la batterie ou alimenter l’implant a travers les tissus humains. Dans ce projet, nous avons conçu, implémenté et testé un récepteur RF à faible puissance et haut-débit de données opérant entre 902 et 928 MHz qui est la bande industrielle-scientifiquemédicale (Industrial, Scientific and Medical) d’Amérique du Nord. Ce récepteur fait partie d’un système de communication bidirectionnel dédié à l’interface sans-fil des dispositifs électroniques implantables et bénéficie d’une nouvelle technique de conversion de modulation par déplacement de fréquence (FSK) en Modulation par déplacement d’amplitude (ASK). Toutes les phases de conception et d’implémentation de la topologie adoptée pour les récepteurs RF sont survolées et discutées dans cette thèse. Les différents étages de circuits sont conçus selon une étude analytique fondée de la modulation FSK et ASK utilisées, ce qui permettra une amélioration des performances notamment le débit de transmission des données et la consommation de puissance. Tous les circuits sont réalisés de façon à ce que la consommation totale et la surface de silicium à réserver soient le minimum possible. Un oscillateur avec verrouillage par injection (Injection-Looked Oscillator - ILO) de faible puissance est réalisé pour assurer la conversion des signaux ASK en FSK. Une combinaison des avantages des deux architectures de modulation d’amplitude et de fréquence, pour les circuits d’émetteurrécepteur sans fil, a été réalisé avec le système proposé. Un module incluant un récepteur de réveil (Wake up) est ajouté afin d’optimiser la consommation totale du circuit en mettant tous les blocs à l’arrêt. Nous avons réalisé un récepteur de réveil RF compact et à faible coût, permettant de très faible niveaux de consommation d’énergie, une bonne sensibilité et une meilleure tolérance aux interférences. Le design est basé sur une topologie homodyne à détection d’enveloppe permettant une transposition directe du signal RF modulé en amplitude en un signal en bande de base. Cette architecture nécessite une architecture peu encombrante à intégrer qui élimine le problème des fréquences image pour la même topologie avec une modulation de fréquence.---------- ABSTRACT ISM band transceiver using a wake-up bloc for wireless body area networks (WBANs) wearable and implantable medical devices is proposed. The system achieves exceptionally low-power consumption and allows a high-data rate by combining the advantages of Frequency-Shift-Keying (FSK) and Amplitude-Shift- Keying (ASK) modulation techniques. The transceiver employs FSK modulation at a data rate of 8 Mbit/s to establish RF link among the medical device and a control unit. Transmitter (Tx) includes a new efficient FSK modulation scheme which offer up to 20 Mb/s of data-rate and dissipates around 0.084 nJ/b. The design of the proposed oscillator achieves variable frequency from 300 kHz to 8 MHz by adjusting the transistors geometry, the on-chip control signal and the tuning capacitors. In the transmitter path, the high-quality LOs Inand Quadrature-phase (I and Q) outputs are produced using a very low-power fully integrated integer-N frequency synthesizer. The architecture of the receiver is inspired from the super-regenerative receiver (SRR) topology which can be used to design a transceiver that is suitable for ASK modulation. In fact, this architecture is based mainly on envelope detection scheme which remove the need to process the carrier phase to reduce the complexity of integrated design. It has been shown too, that the envelope detection scheme is more robust to phase noise than the coherent scheme. The integrated receiver uses on a new FSK-to-ASK conversion technique. The conversion feature that we adopt in the main receiver design is based on the fact that the incident frequency of converter could be differentiated by the amplitude of output signal, which conducts to the frequency-to-amplitude conversion. Thanks to the injection locking oscillator (ILO). the new design of converter is located between the LNA as first part and the envelope detector as second part to benefit from the injection-locking isolation. On-Off-keying (OOK) fully passive wake-up circuit (WuRx) with energy harvesting from Radio Frequency (RF) link is used to optimize the power issipation of the RF transceiver in order to meet the low power requirement. The WuRx operates at the ISM 902–928 MHz. A high efficiency differential rectifier behaves as voltage multiplier. It generates the envelope of the input signal and provides the supply voltage for the rest of blocks including a low-power comparator and reference generators