This book covers the fundamental principles behind the design of ultra-low power radios and how they can form networks to facilitate a variety of applications within healthcare and environmental monitoring, since they may operate for years off a small battery or even harvest energy from the environment. These radios are distinct from conventional radios in that they must operate with very constrained resources and low overhead. This book provides a thorough discussion of the challenges associated with designing radios with such constrained resources, as well as fundamental design concepts and practical approaches to implementing working designs. Coverage includes integrated circuit design, timing and control considerations, fundamental theory behind low power and time domain operation, and network/communication protocol considerations.

Wireless sensor networks have the potential to become the third wireless revolution after wireless voice networks in the 80s and wireless data networks in the late 90s. Unfortunately, radio power consumption is still a major bottleneck to the wide adoption of this technology. Different directions have been explored to minimize the radio consumption, but the major drawback of the proposed solutions is a reduced wireless link robustness. The primary goal of Architectures and Synthesizers for Ultra-low Power Fast Frequency-Hopping WSN Radios is to discuss, in detail, existing and new architectural and circuit level solutions for ultra-low power, robust, uni-directional and bi-directional radio links. Architectures and Synthesizers for Ultra-low Power Fast Frequency-Hopping WSN Radios guides the reader through the many system, circuit and technology trade-offs he will be facing in the design of communication systems for wireless sensor networks. Finally, this book, through different examples realized in both advanced CMOS and bipolar technologies opens a new path in the radio design, showing how radio link robustness can be guaranteed by techniques that were previously exclusively used in radio systems for middle or high end applications like Bluetooth and military communications while still minimizing the overall system power consumption.

This book features the selected articles from the 25th annual symposiums Connecticut Microelectronics and Optoelectronics Consortium (CMOC), that focus on micro/nano-electronics and optoelectronics/Nano-photonics, to cover not only the technologies, but also the applications ranging from biosensors/nano-biosystems, to cyber security.Enabling materials research involving growth and characterization of novel devices such as multi-bit nonvolatile random access memory with fast erase, high performance circuits, and their potential applications in developing new high-speed systems. Other articles focus on emerging nanoelectronic devices including topological insulators, spatial wavefunction switching (SWS) FETs as compact high-speed 2-bit SRAM circuits, quantum dot channel (QDC) FETs. Fundamental work on critical layer thickness in ZnSe/GaAs and other material systems impacts electronic and photonic devise integrating mismatched layers are also reported. While another article investigates linearly graded GaAsP-GaAs system with emphasis on strain relaxation. Based on these technologies, area of analyzes multiple junction solar cells using semiconductors with different energy gaps, as a possible application were also featured; Pixel characterization of protein-based retinal implant, as well as a low-power and low-data-rate (100 kbps) fully integrated CMOS impulse radio ultra-wideband (IR-UWB) transmitter were investigated as a potential candidate for biomedical application. While other articles looked at carbon nanofibers/nanotubes for electrochemical sensing. In the area of cyber security, two articles present encrypted electron beam lithography fabricated nanostructures for authentication and nano-signatures for the identification of authentic electronic components.In summary, papers presented in this volume involve various aspects of high performance materials and devices for implementing high-speed electronic systems.

Wireless Body Area Networks (WBANs) are expected to promote new applications for the ambulatory health monitoring of chronic patients and elderly population, aiming to improve their quality of life and independence. These networks are composed by wireless sensor nodes (WSNs) used for measuring physiological variables (e.g., glucose level in blood or body temperature) or controlling therapeutic devices (e.g., implanted insulin pumps). These nodes should exhibit a high degree of energy autonomy in order to extend their battery lifetime or even make the node supply to rely on harvesting techniques. Typically, the power budget of WSNs is dominated by the wireless link and, hence, many efforts have been directed during the last years toward the implementation of power efficient transceivers. Because of the short range (typically no more than a few meters) and low data rate (typically in between 10 kb/s and 1 Mb/s), simple communication protocols can be employed. One of these protocols, specifically tailored for WBAN applications, is the Bluetooth low energy (BLE) standard. This book describes the challenges and solutions for the design of ultra-low power transceivers for WBANs applications and presents the implementation details of a BLE transceiver prototype. Coverage includes not only the main concepts and architectures for achieving low power consumption, but also the details of the circuit design and its implementation in a standard CMOS technology.

Often WT systems employ the discrete wavelet transform, implemented on a digital signal processor. However, in ultra low-power applications such as biomedical implantable devices, it is not suitable to implement the WT by means of digital circuitry due to the relatively high power consumption associated with the required A/D converter. Low-power analog realization of the wavelet transform enables its application in vivo, e.g. in pacemakers, where the wavelet transform provides a means to extremely reliable cardiac signal detection. In Ultra Low-Power Biomedical Signal Processing we present a novel method for implementing signal processing based on WT in an analog way. The methodology presented focuses on the development of ultra low-power analog integrated circuits that implement the required signal processing, taking into account the limitations imposed by an implantable device.

Smart energy management, both at design time and at run time, is indispensable in modern radios. It requires a careful trade-off between the system’s performance, and its power consumption. Moreover, the design has to be dynamically reconfigurable to optimally balance these parameters at run time, depending on the current operating conditions. Energy Scalable Radio Design describes and applies an energy-driven design strategy to the design of an energy-efficient, highly scalable, pulsed UWB receiver, suitable for low data rate communication and sub-cm ranging. This book meticulously covers the different design steps and the adopted optimizations: System level air interface selection, architectural/algorithmic design space exploration, algorithmic refinement (acquisition, synchronization and ranging algorithms) and circuit level (RTL) implementation based on the FLEXmodule-concept. Measurement results demonstrate the effectiveness and necessity of the energy-driven design strategy.

This book is written for academic and professional researchers designing communication systems for pervasive and low power applications. There is an introduction to wireless sensor networks, but the main emphasis of the book is on design techniques for low power, highly integrated transceivers. Instead of presenting a single design perspective, this book presents the design philosophies from three diverse research groups, providing three completely different strategies for achieving similar goals. By presenting diverse perspectives, this book prepares the reader for the countless design decisions they will be making in their own designs.