85 research outputs found

    Millimeter-Wave CMOS Impulse Radio

    Get PDF

    Ultra-Low-Power Uwb Impulse Radio Design: Architecture, Circuits, And Applications

    Full text link
    Recent advances in home healthcare, environmental sensing, and low power computing have created a need for wireless communication at very low power for low data rate applications. Due to higher energy/bit requirements at lower data -rate, achieving power levels low enough to enable long battery lifetime (~10 years) or power-harvesting supplies have not been possible with traditional approaches. Dutycycled radios have often been proposed in literature as a solution for such applications due to their ability to shut off the static power consumption at low data rates. While earlier radio nodes for such systems have been proposed based on a type of sleepwake scheduling, such implementations are still power hungry due to large synchronization uncertainty (~1[MICRO SIGN]s). In this dissertation, we utilize impulsive signaling and a pulse-coupled oscillator (PCO) based synchronization scheme to facilitate a globally synchronized wireless network. We have modeled this network over a widely varying parameter space and found that it is capable of reducing system cost as well as providing scalability in wireless sensor networks. Based on this scheme, we implemented an FCC compliant, 3-5GHz, timemultiplexed, dual-band UWB impulse radio transceiver, measured to consume only 20[MICRO SIGN]W when the nodes are synchronized for peer-peer communication. At the system level the design was measured to consume 86[MICRO SIGN]W of power, while facilitating multi- hop communication. Simple pulse-shaping circuitry ensures spectral efficiency, FCC compliance and ~30dB band-isolation. Similarly, the band-switchable, ~2ns turn-on receiver implements a non-coherent pulse detection scheme that facilitates low power consumption with -87dBm sensitivity at 100Kbps. Once synchronized the nodes exchange information while duty-cycling, and can use any type of high level network protocols utilized in packet based communication. For robust network performance, a localized synchronization detection scheme based on relative timing and statistics of the PCO firing and the timing pulses ("sync") is reported. No active hand-shaking is required for nodes to detect synchronization. A self-reinforcement scheme also helps maintain synchronization even in the presence of miss-detections. Finally we discuss unique ways to exploit properties of pulse coupled oscillator networks to realize novel low power event communication, prioritization, localization and immediate neighborhood validation for low power wireless sensor applications

    Energy detection receiver with TOA estimation enabling positioning in passive UWB-RFID system

    Full text link

    Design of low power CMOS UWB transceiver ICs

    Get PDF
    Master'sMASTER OF ENGINEERIN

    IC design, UWB synchronization circuit

    Get PDF
    Master'sMASTER OF ENGINEERIN

    Design and Implementation of a Low‐Power Wireless Respiration Monitoring Sensor

    Get PDF
    Wireless devices for monitoring of respiration activities can play a major role in advancing modern home-based health care applications. Existing methods for respiration monitoring require special algorithms and high precision filters to eliminate noise and other motion artifacts. These necessitate additional power consuming circuitry for further signal conditioning. This dissertation is particularly focused on a novel approach of respiration monitoring based on a PVDF-based pyroelectric transducer. Low-power, low-noise, and fully integrated charge amplifiers are designed to serve as the front-end amplifier of the sensor to efficiently convert the charge generated by the transducer into a proportional voltage signal. To transmit the respiration data wirelessly, a lowpower transmitter design is crucial. This energy constraint motivates the exploration of the design of a duty-cycled transmitter, where the radio is designed to be turned off most of the time and turned on only for a short duration of time. Due to its inherent duty-cycled nature, impulse radio ultra-wideband (IR-UWB) transmitter is an ideal candidate for the implementation of a duty-cycled radio. To achieve better energy efficiency and longer battery lifetime a low-power low-complexity OOK (on-off keying) based impulse radio ultra-wideband (IR-UWB) transmitter is designed and implemented using standard CMOS process. Initial simulation and test results exhibit a promising advancement towards the development of an energy-efficient wireless sensor for monitoring of respiration activities

    A Mixed-Signal Demodulator for a Low-Complexity IR-UWB Receiver: Methodology, Simulation and Design

    Get PDF
    This works presents an integrated 0.18μm CMOS 2-PPM demodulator based on a switched capacitor network for an Energy Detection Impulse-Radio UWB receiver. The circuit has been designed using a top-down methodology that allows to discover the impact of low-level non-idealities on system-level performance. Through the use of a mixed signal simulation environment, performance figures have been obtained which helped evaluate the influence at system-level of the non-idealities of the most critical block. Results show that the circuit allows the replacement of the ADC typically employed in Energy Detection receivers and provides about infinite equivalent quantization resolution. The demodulator achieves 190 pJ/bit at 1.8V
    corecore