Our research will radically transform spectrum access through new availability and coordination methods. Consequently, this project targets to impact spectrum policy and the FCC via demonstration of novel usage cases of spectral bands by combining spectrum spanning two orders of magnitude. This project will impact industry through demonstration of these results coupled with the PI’s extensive collaborative industry network. Finally, the project includes an inter-disciplinary education plan and the team includes multiple Ph.D. students from under-represented groups.
Impact on society beyond science and technology:
- Our project will impact standards bodies as it demonstrates attaining both long range communication and spatial multiplexing in antenna-limited devices.
- Our project will impact standards bodies as it shows how enhancements to existing standards and fusion of diverse bands can yield vast performance gains.
- Our project technology will impact standards bodies as our system performance scales much better with speed and client density as compared to the IEEE standard based systems.
Impact on knowledge and technique:
- We reported a pico-second pulse receiver based on a three-stage divide-by-8 injection-locked frequency divider. The receiver operates for pulses with center frequency of 77 GHz and locks its output to the 9.6-GHz repetition rate with an effective locking range of 142 MHz. This receiver, which consumes 42 mW dc power, is used to demonstrate wireless clock synchronization with a 0.29ps RMS timing jitter and indicates an estimated sensitivity of −65.5 dBm in detecting pico-second pulses.
- We proposed MOCA (Mobility resilience and Overhead Constrained Adaptation) for directional 60 GHz links with mobile clients. MOCA provides a low overhead technique for rapidly identifying link breakage resulting from mobility induced blockage and sector misalignment, and dynamically selects and adapts beamwidth in response to nodal and environmental mobility, with an objective to maximize average link throughput.
- We proposed DSSM (Diverse Spectrum Spatial Multiplexing), which is the first system to enable uplink spatial multiplexing for clients with a single in-band antenna by spoofing an unmodified AP to infer that the single-antenna client has an array, and overcomes the constraints that mobile devices (No. antennas) cannot practically employ multi- or single-user transmit beamforming, that distributed uplink transmitters have no infrastructure (wire) connecting them, and that the medium access is decentralized and performed independently by each device in a random access manner.
- We proposed Searchlight: Tracking Device Mobility using Indoor Luminaries to adapt 60 GHz Beams. We design and experimentally evaluate a system to achieve high data rate links in the mm-wave band despite device mobility (a key challenge limiting the high-rate capability of mm-wave transmissions in practical systems) by expanding our architecture to include spectrum in the visible light band (430-770 THz range). In particular, we develop a mm-wave system design which tracks device mobility by passively sensing changes in light intensity from indoor light sources and infers any changes in mm-wave beams at WATabit nodes to maintain high SNR links despite device mobility. As such, we demonstrate robust and extremely fast mm-wave links to share data and CSI with very low latency, necessary to form a virtual array in the legacy band and thereby achieve uplink spatial multiplexing.
- We reported our Self-Mixing Picosecond Impulse Receiver with an On-Chip Antenna for High-Speed Wireless Clock Synchronization as the first receiver in silicon that can detect sub-6-ps electromagnetic pulses and use them for wireless time transfer.
- We reported a Nonlinear Impulse Sampler for Detection of Picosecond Pulses in 90 nm SiGe BiCMOS. Our results show that the sampler can detect impulses as short as 100 ps. The chip is fabricated in IBM 9HP BiCMOS process technology and occupies an area of 1.02mm2. The power consumption of the chip is 105mW.
- To the best of our knowledge, we have designed the first PIN diode-based THz pulse radiator implemented in a silicon-based process. In this work, the reverse-recovery of a standard PIN diode device in 130-nm BiCMOS technology is used to generate THz-pulses (wideband frequency comb), which are radiated through a broadband on-chip antenna.
- We present a novel system to expand our diverse spectrum architecture, and exploit intensity measurements of visible light sources (430-770 THz frequency range) to track device mobility, and continuously adapt mm-wave phased array antenna beams without requiring any in-band beam-search.
Impact on technology transfer:
- Our project’s research will not only enable new dimensions for scaling WLAN throughput and range but also will show how a design based on wide aperture enables high frequency bands to scale to achieve previously impossible capacity gains.
Impact on information resources that form infrastructure:
- Our project’s development of an open-access repository with the hardware design, source code for its operational software, and an open-source toolkit will be preserved and publicly available.
Impact on the development of human resources:
- The project is providing research opportunities for undergraduate and graduate students from a variety of disciplines. Our research team includes women and minority students.
- The NeTS project provided data for the Postdoctoral degree research of Adriana Flores, Ph.D Engineering, Rice University. Thesis: “Scaling Uplink Throughput in WLANS.”
- The NeTS project provided data for the Master’s degree research of Kumail Haider, MS Engineering, Rice University. Thesis: “Overhead Constrained Joint Adaptation of MCS, Beamwidth and Antenna Sectors for 60 GHz WLANs with Mobile Clients.”
- The NeTS project provided data for the Master’s degree research of Yasaman GhasemPour, MS Engineering, Rice University. Thesis: “Maximizing Sum Rate in 60 GHZ Downlink MU-MIMO.”
- The NeTS project provided data for the Master’s degree research of J. Chen, MS Engineering, Rice University. Thesis: “Pseudo Lateration: Millimeter-Wave Localization Using a Single Infrastructure Anchor.”
- The NeTS project provided data for the Master’s degree research of P. Nayak, MS Engineering, Rice University. Thesis: “Performance Evaluation of MU-MIMO WLANs under the impact of traffic dynamics.”
- The NeTS project provided data for the Master’s degree research of J. Zhang, MS Engineering, Rice University. Thesis: “MAC Layer DATA/ACK Handshake in the Hybrid VLC-RF System.”
- The NeTS project provided data for the Postdoctoral degree research of Xu Zhang, Ph.D. Engineering, Rice University.