• Research Approach

    The WISE-Circuits group develops tightly-coupled system solutions derived at the intersection of electronics with a specific focus on analog and radio frequency integrated circuits, security, digital signal processing, sensing and wireless communications for future energy-constrained applications. We develop unique application-driven system solutions that would not be possible through isolated investigation. Our approach highlights cross-layer optimization from circuits to protocols to drastically improve energy efficiency and obtain higher performance.

  • Current Research Project Areas

    ✫ Bio-electronic sensors for diagnosis and disease monitoring

    ✫ Security of IoT systems

    ✫ Next-generation spectrum-aware and secure wireless communication systems

    ✫ Electronic-photonic integrated systems for non-invasive brain activity mapping

  • Past Research Projects

    Wireless Security for Internet of Things

    Collaborators: Phillip Nadeau, Daniel Richman, Chiraag Juvekar, Kapil Vaidya, Professor Anantha P. Chandrakasan

    Security is the most important consideration in future low-power wireless networks focused on connecting edge devices. It has been shown that life critical implantable devices controlled over a wireless link can now be attacked, motivating the need to establish end-to-end secure system solutions. We co-developed wireless protocols and secure RF radio architectures that provide unique security in physical layer to enable new security paradigms for the next generation of wireless connectivity. This work specifically addresses a wireless attack scenario, selective jamming denial of service, where the adversary corrupts transmitted messages targeting a single victim. Selective jamming is particularly challenging as it conceals the attacker’s identity contrary to broadband-wireless jamming. Even though current wireless standards for IoT devices employ packet-level frequency-hopping protocols, they continue to be vulnerable to selective jamming since packet durations are long enough to allow the packet to be localized and blocked. To counter this attack, we developed an ultra-fast bit-level frequency-hopping scheme with a cryptographically secure data-driven dynamic channel selection scheme by exploiting the frequency agility of bulk acoustic wave (BAW) resonators and novel RF circuit architectures with multi-channel coverage.

    Related Publications: ESSCIRC 2017, RFIC 2018

    Press Coverage: MIT News, CNET, EurekAlert!, Engadget, ElectronicsWeekly.com, Hurriyet, Herkese Bilim Teknoloji

    © IEEE RFIC 2018

    Spectrum-Aware Wireless Communications

    Collaborators: Tanbir Haque, Professor John Wright (co-advisor), Professor Peter R. Kinget (advisor)

    Compressed sensing has been extensively used for image reconstruction. It has been demonstrated by Rice University that a "Single-Pixel Camera" that exploits compressive sampling can obtain an image with less measurements than the number of pixels under prior condition of sparsity.

    In Dr. Yazicigil's PhD research work, she exploited the compressed sensing to take a "snapshot" of the spectrum. Compressed sensing allows the designers to build very fast, low power and wideband spectrum sensors with lower overhead under the prior assumption of sparsity.

    Wideband, Energy-Efficient and Rapid Interferer Detectors with Compressed-Sensing Quadrature Analog-to-Information Converters

    Spectrum is the "lifeblood" of the future wireless networks and the "data storm" driven by the emerging technologies like Internet of Things, video over wireless will lead to a pressing "artificial" spectrum scarcity. Future “smart” terminals will need to quickly assess the spectrum usage and opportunistically use the available spectrum to overcome this challenge. Such "smart" terminals require spectrum sensing for interferer avoidance. The integrated interferer detectors need to be fast, wideband and energy efficient.

    Band-pass compressed-sensing (CS) interferer detectors with a Quadrature Analog-to-Information Converter (QAIC) offers a novel approach to attack the search for the quick detection of interferers in a wideband spectrum in an energy efficient way. Our first band-pass CS QAIC system demonstration senses a wideband 1GHz span with a 20MHz resolution bandwidth in 4.4μsecs, offering 50x faster scan time compared to traditional sweeping spectrum scanners and 6.3x compressed aggregate sampling rate compared to traditional concurrent Nyquist-rate approaches. Such detectors are key cornerstones for future multi-tiered shared spectrum access solutions with dynamic spectrum sensing.

    Related Publications: JSSC2015 (Invited paper), ISSCC 2015, TCAS-I 2015, ISCAS 2016, Signal Processing Magazine 2019

    Patents: Circuits and Methods for Detecting Interferers

    © IEEE ISSCC 2015, IEEE JSSC 2015 (invited paper)

    © IEEE ISSCC 2015, IEEE JSSC 2015 (invited paper)

    Analog-to-Information Converters for Dynamic Spectrum Environments with Changing Sparsity Conditions

    CS architectures rely on signal sparsity and the number of CS hardware branches is proportional to the number of signals to be detected. The key remaining challenge when implementing CS analog-to-information converters with a fixed number of hardware branches is to how to make them work reliably under changing sparsity conditions. Our second band-pass CS time-segmented QAIC system extends its interferer detection capability through time segmentation and adaptive thresholding in dynamic spectrum environments without any additional silicon area.

    Related Publications: RFIC 2016 , Asilomar 2016 (invited paper), TCAS-I 2018, Signal Processing Magazine 2019

    © IEEE RFIC 2016

  • Research Resources & Facilities

    Chip Fabrication

    We have access to a number of different semiconductor processes for the fabrication of our circuits through a fabrication service provider (e.g., MOSIS, MUSE semiconductor) as well as through direct relationships with companies and foundries. We currently mainly use 65nm CMOS and 40nm CMOS technologies.

    CAD Tools and Computing Resources

    We use a full set of industrial grade design tools for our IC designs. This includes tools suites from Cadence and Mentor. We have access to the BU Shared Computing Cluster and Engineering Grid for our research.

    Analog, Radio-Frequency, Mixed-Signal Integrated Circuit Characterization

    We currently have a state-of-the-art measurement facility for integrated circuit characterization from DC to 44 GHz. Our instruments allow a full characterization in the frequency domain and time domain. The Boston University Photonics Center has several shared laboratory resources including Optoelectronic Processing Facility, Precision Measurement Laboratory, FIB/TEM Facility, and Materials Science Core Facilities.