Research Area
Year Published

44 Results

January 6, 2020

Aeroelastic Preliminary-Design Optimization of Communication Tower Structures

AIAA Scitech

An aero-structural optimization framework is presented to derive cost-optimal designs for communication tower structures. Preliminary designs are sought given certain high-level requirements such as tower height, wind speed and antenna loading. In order to rapidly search the design space, low-order modeling is emphasized for computational efficiency.

By: Vishvas Suryakumar, Paul Varkey, Ben Thomsen, Jack Marriott, David Liu, Abhishek Tiwari

July 8, 2019

Gabor Frame-Based Sparsification and Radiation Boundary Conditions for Parabolic Wave Equations

IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI)

This paper proposes to use Gabor frames to lower the memory and CPU costs of split-step Fourier PE solvers and allow for the easy implementation of RBCs. Gabor transforms have been used before for PE-based modeling of geophysical problems (Chen et al, Geophysics, 2006, 71(2), S37-S52), but they have not yet been extensively used in electromagnetics

By: Max Bright, Julius Kusuma, Eric Michielssen

July 8, 2019

Hybrid Parabolic Equation – Integral Equation Solvers for Analyzing Long Range Propagation Over Complex Terrain

IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI)

This paper proposes a new framework for modeling NLOS propagation using a PE – IE hybrid. The framework’s PE component simulates field propagation from the transmitting antenna through the atmosphere/ionosphere, and uses a wide-angle split-step Fourier method enhanced by Gabor-Daubechies sparsification techniques that produce significant computational savings over earlier PE solution methods.

By: Eric Michielssen, Max Bright, Julius Kusuma

June 17, 2019

Panoptic Segmentation

Conference Computer Vision and Pattern Recognition (CVPR)

We propose and study a task we name panoptic segmentation (PS). Panoptic segmentation unifies the typically distinct tasks of semantic segmentation (assign a class label to each pixel) and instance segmentation (detect and segment each object instance). The proposed task requires generating a coherent scene segmentation that is rich and complete, an important step toward real-world vision systems.

By: Alexander Kirillov, Kaiming He, Ross Girshick, Carsten Rother, Piotr Dollar

June 2, 2019

Demonstration of a 40Gbps Bi-directional Air-to-Ground Millimeter Wave Communication Link

IEEE International Microwave Symposium (IMS)

We describe the design, development, and field demonstration of a high-throughput E-band communication link between a ground station and a Cessna aircraft flying at an altitude of 7km and a top speed of 463km/h.

By: Qi Tang, Abhishek Tiwari, Inigo del Portillo, Michael Reed, Hongyu Zhou, Dudi Shmueli, Gunnar Ristroph, Steven Cashion, Dawei Zhang, Joseph Stewart, Pratheep Bondalapati, Qi Qu, Yan Yan, Bob Proctor, Hamid Hemmati

May 19, 2019

Facebook Disaster Maps: Aggregate Insights for Crisis Response & Recovery

Conference on Information Systems for Crisis Response and Management (ISCRAM)

In this paper, we describe the data and methodology that power Facebook Disaster Maps. These maps utilize information about Facebook usage in areas impacted by natural hazards, producing aggregate pictures of how the population is affected by and responding to the hazard. The maps include insights into evacuations, cell network connectivity, access to electricity, and long-term displacement.

By: Paige Maas, Shankar Iyer, Andreas Gros, Wonhee Park, Laura McGorman, Chaya Nayak, Alex Dow

January 30, 2019

Heavy Ion Radiation Assessment of a 100G/200G Commercial Optical Coherent DSP ASIC

SPIE Photonics West

We assess the viability of a state-of-the-art 100G/200G commercial optical coherent DSP ASIC (16 nm FinFET CMOS technology) for space applications through heavy ion testing to (1) screen for destructive SELs and (2) observe for nondestructive heavy ion SEEs on the ASIC.

By: Raichelle Aniceto, Randall Milanowski, Steve McClure, Alexa Aguilar, Slaven Moro, Eric D. Miller, Kerri Cahoy

December 8, 2018

From Satellite Imagery to Disaster Insights

AI for Social Good Workshop at NeurIPS 2018

The use of satellite imagery has become increasingly popular for disaster monitoring and response. After a disaster, it is important to prioritize rescue operations, disaster response and coordinate relief efforts. These have to be carried out in a fast and efficient manner since resources are often limited in disaster affected areas and it’s extremely important to identify the areas of maximum damage. However, most of the existing disaster mapping efforts are manual which is time-consuming and often leads to erroneous results.

By: Jigar Doshi, Saikat Basu, Guan Pang

November 27, 2018

Machine Learning for Reliable mmWave Systems: Blockage Prediction and Proactive Handoff

IEEE Global Conference on Signal and Information Processing (GlobalSIP)

The sensitivity of millimeter wave (mmWave) signals to blockages is a fundamental challenge for mobile mmWave communication systems. The sudden blockage of the line-of-sight (LOS) link between the base station and the mobile user normally leads to disconnecting the communication session, which highly impacts the system reliability. Further, reconnecting the user to another LOS base station incurs high beam training overhead and critical latency problem. In this paper, we leverage machine learning tools and propose a novel solution for these reliability and latency challenges in mmWave MIMO systems

By: Ahmed Alkhateeb, Iz Beltagy, Sam Alex

October 12, 2018

Flight Control System Design for a High Altitude, Long Endurance Airplane: Sensor Distribution and Flexible Modes Control

This manuscript outlines the control system design process for a solar-powered unmanned high-altitude long endurance flying wing aircraft, called Aquila, which was developed by the Facebook Connectivity Lab to serve as communication backhaul for remote and rural connectivity.

By: Hamidreza Bolandhemmat